- *-max-key-length
- *-max-name-length
- *-max-value-length
- *import-preferences
- *system-node-for-package
- *system-root
- *user-node-for-package
- *user-root
- absolute-path
- add-node-change-listener
- add-preference-change-listener
- children-names
- clear
- export-node
- export-subtree
- flush
- get
- get-boolean?
- get-byte-array
- get-double
- get-float
- get-int
- get-long
- keys
- name
- node
- node-exists
- parent
- put
- put-boolean
- put-byte-array
- put-double
- put-float
- put-int
- put-long
- remove
- remove-node
- remove-node-change-listener
- remove-preference-change-listener
- sync
- to-string
- user-node?
jdk.util.prefs.Preferences
A node in a hierarchical collection of preference data. This class allows applications to store and retrieve user and system preference and configuration data. This data is stored persistently in an implementation-dependent backing store. Typical implementations include flat files, OS-specific registries, directory servers and SQL databases. The user of this class needn't be concerned with details of the backing store.
There are two separate trees of preference nodes, one for user preferences and one for system preferences. Each user has a separate user preference tree, and all users in a given system share the same system preference tree. The precise description of "user" and "system" will vary from implementation to implementation. Typical information stored in the user preference tree might include font choice, color choice, or preferred window location and size for a particular application. Typical information stored in the system preference tree might include installation configuration data for an application.
Nodes in a preference tree are named in a similar fashion to directories in a hierarchical file system. Every node in a preference tree has a node name (which is not necessarily unique), a unique absolute path name, and a path name relative to each ancestor including itself.
The root node has a node name of the empty string (""). Every other node has an arbitrary node name, specified at the time it is created. The only restrictions on this name are that it cannot be the empty string, and it cannot contain the slash character ('/').
The root node has an absolute path name of "/". Children of the root node have absolute path names of "/" <node name>. All other nodes have absolute path names of <parent's absolute path name> "/" <node name>. Note that all absolute path names begin with the slash character.
A node n's path name relative to its ancestor a is simply the string that must be appended to a's absolute path name in order to form n's absolute path name, with the initial slash character (if present) removed. Note that:
No relative path names begin with the slash character. Every node's path name relative to itself is the empty string. Every node's path name relative to its parent is its node name (except for the root node, which does not have a parent). Every node's path name relative to the root is its absolute path name with the initial slash character removed.
Note finally that:
No path name contains multiple consecutive slash characters. No path name with the exception of the root's absolute path name ends in the slash character. Any string that conforms to these two rules is a valid path name.
All of the methods that modify preferences data are permitted to operate asynchronously; they may return immediately, and changes will eventually propagate to the persistent backing store with an implementation-dependent delay. The flush method may be used to synchronously force updates to the backing store. Normal termination of the Java Virtual Machine will not result in the loss of pending updates -- an explicit flush invocation is not required upon termination to ensure that pending updates are made persistent.
All of the methods that read preferences from a Preferences object require the invoker to provide a default value. The default value is returned if no value has been previously set or if the backing store is unavailable. The intent is to allow applications to operate, albeit with slightly degraded functionality, even if the backing store becomes unavailable. Several methods, like flush, have semantics that prevent them from operating if the backing store is unavailable. Ordinary applications should have no need to invoke any of these methods, which can be identified by the fact that they are declared to throw BackingStoreException.
The methods in this class may be invoked concurrently by multiple threads in a single JVM without the need for external synchronization, and the results will be equivalent to some serial execution. If this class is used concurrently by multiple JVMs that store their preference data in the same backing store, the data store will not be corrupted, but no other guarantees are made concerning the consistency of the preference data.
This class contains an export/import facility, allowing preferences to be "exported" to an XML document, and XML documents representing preferences to be "imported" back into the system. This facility may be used to back up all or part of a preference tree, and subsequently restore from the backup.
The XML document has the following DOCTYPE declaration:
<!DOCTYPE preferences SYSTEM "http://java.sun.com/dtd/preferences.dtd">
Note that the system URI (http://java.sun.com/dtd/preferences.dtd) is not accessed when exporting or importing preferences; it merely serves as a string to uniquely identify the DTD, which is:
<?xml version="1.0" encoding="UTF-8"?>
<!-- DTD for a Preferences tree. --> <!-- The preferences element is at the root of an XML document representing a Preferences tree. --><!ELEMENT preferences (root)>
<!-- The preferences element contains an optional version attribute, which specifies version of DTD. --><!ATTLIST preferences EXTERNAL_XML_VERSION CDATA "0.0" >
<!-- The root element has a map representing the root's preferences (if any), and one node for each child of the root (if any). --><!ELEMENT root (map, node*) >
<!-- Additionally, the root contains a type attribute, which specifies whether it's the system or user root. --><!ATTLIST root type (system|user) #REQUIRED >
<!-- Each node has a map representing its preferences (if any), and one node for each child (if any). --><!ELEMENT node (map, node*) >
<!-- Additionally, each node has a name attribute --><!ATTLIST node name CDATA #REQUIRED >
<!-- A map represents the preferences stored at a node (if any). --><!ELEMENT map (entry*) >
<!-- An entry represents a single preference, which is simply a key-value pair. --><!ELEMENT entry EMPTY >
<!ATTLIST entry key CDATA #REQUIRED value CDATA #REQUIRED >
Every Preferences implementation must have an associated PreferencesFactory implementation. Every Java(TM) SE implementation must provide some means of specifying which PreferencesFactory implementation is used to generate the root preferences nodes. This allows the administrator to replace the default preferences implementation with an alternative implementation.
Implementation note: In Sun's JRE, the PreferencesFactory implementation is located as follows:
If the system property java.util.prefs.PreferencesFactory is defined, then it is taken to be the fully-qualified name of a class implementing the PreferencesFactory interface. The class is loaded and instantiated; if this process fails then an unspecified error is thrown.
If a PreferencesFactory implementation class file has been installed in a jar file that is visible to the system class loader, and that jar file contains a provider-configuration file named java.util.prefs.PreferencesFactory in the resource directory META-INF/services, then the first class name specified in that file is taken. If more than one such jar file is provided, the first one found will be used. The class is loaded and instantiated; if this process fails then an unspecified error is thrown.
Finally, if neither the above-mentioned system property nor an extension jar file is provided, then the system-wide default PreferencesFactory implementation for the underlying platform is loaded and instantiated.
A node in a hierarchical collection of preference data. This class
allows applications to store and retrieve user and system
preference and configuration data. This data is stored
persistently in an implementation-dependent backing store. Typical
implementations include flat files, OS-specific registries,
directory servers and SQL databases. The user of this class needn't
be concerned with details of the backing store.
There are two separate trees of preference nodes, one for user
preferences and one for system preferences. Each user has a separate user
preference tree, and all users in a given system share the same system
preference tree. The precise description of "user" and "system" will vary
from implementation to implementation. Typical information stored in the
user preference tree might include font choice, color choice, or preferred
window location and size for a particular application. Typical information
stored in the system preference tree might include installation
configuration data for an application.
Nodes in a preference tree are named in a similar fashion to
directories in a hierarchical file system. Every node in a preference
tree has a node name (which is not necessarily unique),
a unique absolute path name, and a path name relative to each
ancestor including itself.
The root node has a node name of the empty string (""). Every other
node has an arbitrary node name, specified at the time it is created. The
only restrictions on this name are that it cannot be the empty string, and
it cannot contain the slash character ('/').
The root node has an absolute path name of "/". Children of
the root node have absolute path names of "/" <node
name>. All other nodes have absolute path names of <parent's
absolute path name> "/" <node name>.
Note that all absolute path names begin with the slash character.
A node n's path name relative to its ancestor a
is simply the string that must be appended to a's absolute path name
in order to form n's absolute path name, with the initial slash
character (if present) removed. Note that:
No relative path names begin with the slash character.
Every node's path name relative to itself is the empty string.
Every node's path name relative to its parent is its node name (except
for the root node, which does not have a parent).
Every node's path name relative to the root is its absolute path name
with the initial slash character removed.
Note finally that:
No path name contains multiple consecutive slash characters.
No path name with the exception of the root's absolute path name
ends in the slash character.
Any string that conforms to these two rules is a valid path name.
All of the methods that modify preferences data are permitted to operate
asynchronously; they may return immediately, and changes will eventually
propagate to the persistent backing store with an implementation-dependent
delay. The flush method may be used to synchronously force
updates to the backing store. Normal termination of the Java Virtual
Machine will not result in the loss of pending updates -- an explicit
flush invocation is not required upon termination to ensure
that pending updates are made persistent.
All of the methods that read preferences from a Preferences
object require the invoker to provide a default value. The default value is
returned if no value has been previously set or if the backing store is
unavailable. The intent is to allow applications to operate, albeit
with slightly degraded functionality, even if the backing store becomes
unavailable. Several methods, like flush, have semantics that
prevent them from operating if the backing store is unavailable. Ordinary
applications should have no need to invoke any of these methods, which can
be identified by the fact that they are declared to throw BackingStoreException.
The methods in this class may be invoked concurrently by multiple threads
in a single JVM without the need for external synchronization, and the
results will be equivalent to some serial execution. If this class is used
concurrently by multiple JVMs that store their preference data in
the same backing store, the data store will not be corrupted, but no
other guarantees are made concerning the consistency of the preference
data.
This class contains an export/import facility, allowing preferences
to be "exported" to an XML document, and XML documents representing
preferences to be "imported" back into the system. This facility
may be used to back up all or part of a preference tree, and
subsequently restore from the backup.
The XML document has the following DOCTYPE declaration:
<!DOCTYPE preferences SYSTEM "http://java.sun.com/dtd/preferences.dtd">
Note that the system URI (http://java.sun.com/dtd/preferences.dtd) is
not accessed when exporting or importing preferences; it merely
serves as a string to uniquely identify the DTD, which is:
<?xml version="1.0" encoding="UTF-8"?>
<!-- DTD for a Preferences tree. -->
<!-- The preferences element is at the root of an XML document
representing a Preferences tree. -->
<!ELEMENT preferences (root)>
<!-- The preferences element contains an optional version attribute,
which specifies version of DTD. -->
<!ATTLIST preferences EXTERNAL_XML_VERSION CDATA "0.0" >
<!-- The root element has a map representing the root's preferences
(if any), and one node for each child of the root (if any). -->
<!ELEMENT root (map, node*) >
<!-- Additionally, the root contains a type attribute, which
specifies whether it's the system or user root. -->
<!ATTLIST root
type (system|user) #REQUIRED >
<!-- Each node has a map representing its preferences (if any),
and one node for each child (if any). -->
<!ELEMENT node (map, node*) >
<!-- Additionally, each node has a name attribute -->
<!ATTLIST node
name CDATA #REQUIRED >
<!-- A map represents the preferences stored at a node (if any). -->
<!ELEMENT map (entry*) >
<!-- An entry represents a single preference, which is simply
a key-value pair. -->
<!ELEMENT entry EMPTY >
<!ATTLIST entry
key CDATA #REQUIRED
value CDATA #REQUIRED >
Every Preferences implementation must have an associated PreferencesFactory implementation. Every Java(TM) SE implementation must provide
some means of specifying which PreferencesFactory implementation
is used to generate the root preferences nodes. This allows the
administrator to replace the default preferences implementation with an
alternative implementation.
Implementation note: In Sun's JRE, the PreferencesFactory
implementation is located as follows:
If the system property
java.util.prefs.PreferencesFactory is defined, then it is
taken to be the fully-qualified name of a class implementing the
PreferencesFactory interface. The class is loaded and
instantiated; if this process fails then an unspecified error is
thrown.
If a PreferencesFactory implementation class file
has been installed in a jar file that is visible to the
system class loader,
and that jar file contains a provider-configuration file named
java.util.prefs.PreferencesFactory in the resource
directory META-INF/services, then the first class name
specified in that file is taken. If more than one such jar file is
provided, the first one found will be used. The class is loaded
and instantiated; if this process fails then an unspecified error
is thrown.
Finally, if neither the above-mentioned system property nor
an extension jar file is provided, then the system-wide default
PreferencesFactory implementation for the underlying
platform is loaded and instantiated.*-max-key-lengthclj
Static Constant.
Maximum length of string allowed as a key (80 characters).
type: int
Static Constant. Maximum length of string allowed as a key (80 characters). type: int
*-max-name-lengthclj
Static Constant.
Maximum length of a node name (80 characters).
type: int
Static Constant. Maximum length of a node name (80 characters). type: int
*-max-value-lengthclj
Static Constant.
Maximum length of string allowed as a value (8192 characters).
type: int
Static Constant. Maximum length of string allowed as a value (8192 characters). type: int
*import-preferencesclj
(*import-preferences is)Imports all of the preferences represented by the XML document on the specified input stream. The document may represent user preferences or system preferences. If it represents user preferences, the preferences will be imported into the calling user's preference tree (even if they originally came from a different user's preference tree). If any of the preferences described by the document inhabit preference nodes that do not exist, the nodes will be created.
The XML document must have the following DOCTYPE declaration:
<!DOCTYPE preferences SYSTEM "http://java.sun.com/dtd/preferences.dtd">
(This method is designed for use in conjunction with exportNode(OutputStream) and exportSubtree(OutputStream).
This method is an exception to the general rule that the results of concurrently executing multiple methods in this class yields results equivalent to some serial execution. The method behaves as if implemented on top of the other public methods in this class, notably node(String) and put(String, String).
is - the input stream from which to read the XML document. - java.io.InputStream
throws: java.io.IOException - if reading from the specified input stream results in an IOException.
Imports all of the preferences represented by the XML document on the specified input stream. The document may represent user preferences or system preferences. If it represents user preferences, the preferences will be imported into the calling user's preference tree (even if they originally came from a different user's preference tree). If any of the preferences described by the document inhabit preference nodes that do not exist, the nodes will be created. The XML document must have the following DOCTYPE declaration: <!DOCTYPE preferences SYSTEM "http://java.sun.com/dtd/preferences.dtd"> (This method is designed for use in conjunction with exportNode(OutputStream) and exportSubtree(OutputStream). This method is an exception to the general rule that the results of concurrently executing multiple methods in this class yields results equivalent to some serial execution. The method behaves as if implemented on top of the other public methods in this class, notably node(String) and put(String, String). is - the input stream from which to read the XML document. - `java.io.InputStream` throws: java.io.IOException - if reading from the specified input stream results in an IOException.
*system-node-for-packageclj
(*system-node-for-package c)Returns the preference node from the system preference tree that is associated (by convention) with the specified class's package. The convention is as follows: the absolute path name of the node is the fully qualified package name, preceded by a slash ('/'), and with each period ('.') replaced by a slash. For example the absolute path name of the node associated with the class com.acme.widget.Foo is /com/acme/widget.
This convention does not apply to the unnamed package, whose associated preference node is <unnamed>. This node is not intended for long term use, but for convenience in the early development of programs that do not yet belong to a package, and for "throwaway" programs. Valuable data should not be stored at this node as it is shared by all programs that use it.
A class Foo wishing to access preferences pertaining to its package can obtain a preference node as follows:
static Preferences prefs = Preferences.systemNodeForPackage(Foo.class); This idiom obviates the need for using a string to describe the preferences node and decreases the likelihood of a run-time failure. (If the class name is misspelled, it will typically result in a compile-time error.)
Invoking this method will result in the creation of the returned node and its ancestors if they do not already exist. If the returned node did not exist prior to this call, this node and any ancestors that were created by this call are not guaranteed to become permanent until the flush method is called on the returned node (or one of its ancestors or descendants).
c - the class for whose package a system preference node is desired. - java.lang.Class
returns: the system preference node associated with the package of which
c is a member. - java.util.prefs.Preferences
throws: java.lang.NullPointerException - if c is null.
Returns the preference node from the system preference tree that is
associated (by convention) with the specified class's package. The
convention is as follows: the absolute path name of the node is the
fully qualified package name, preceded by a slash ('/'), and
with each period ('.') replaced by a slash. For example the
absolute path name of the node associated with the class
com.acme.widget.Foo is /com/acme/widget.
This convention does not apply to the unnamed package, whose
associated preference node is <unnamed>. This node
is not intended for long term use, but for convenience in the early
development of programs that do not yet belong to a package, and
for "throwaway" programs. Valuable data should not be stored
at this node as it is shared by all programs that use it.
A class Foo wishing to access preferences pertaining to its
package can obtain a preference node as follows:
static Preferences prefs = Preferences.systemNodeForPackage(Foo.class);
This idiom obviates the need for using a string to describe the
preferences node and decreases the likelihood of a run-time failure.
(If the class name is misspelled, it will typically result in a
compile-time error.)
Invoking this method will result in the creation of the returned
node and its ancestors if they do not already exist. If the returned
node did not exist prior to this call, this node and any ancestors that
were created by this call are not guaranteed to become permanent until
the flush method is called on the returned node (or one of its
ancestors or descendants).
c - the class for whose package a system preference node is desired. - `java.lang.Class`
returns: the system preference node associated with the package of which
c is a member. - `java.util.prefs.Preferences`
throws: java.lang.NullPointerException - if c is null.*system-rootclj
(*system-root)Returns the root preference node for the system.
returns: the root preference node for the system. - java.util.prefs.Preferences
throws: java.lang.SecurityException - If a security manager is present and it denies RuntimePermission("preferences").
Returns the root preference node for the system.
returns: the root preference node for the system. - `java.util.prefs.Preferences`
throws: java.lang.SecurityException - If a security manager is present and it denies RuntimePermission("preferences").*user-node-for-packageclj
(*user-node-for-package c)Returns the preference node from the calling user's preference tree that is associated (by convention) with the specified class's package. The convention is as follows: the absolute path name of the node is the fully qualified package name, preceded by a slash ('/'), and with each period ('.') replaced by a slash. For example the absolute path name of the node associated with the class com.acme.widget.Foo is /com/acme/widget.
This convention does not apply to the unnamed package, whose associated preference node is <unnamed>. This node is not intended for long term use, but for convenience in the early development of programs that do not yet belong to a package, and for "throwaway" programs. Valuable data should not be stored at this node as it is shared by all programs that use it.
A class Foo wishing to access preferences pertaining to its package can obtain a preference node as follows:
static Preferences prefs = Preferences.userNodeForPackage(Foo.class);
This idiom obviates the need for using a string to describe the preferences node and decreases the likelihood of a run-time failure. (If the class name is misspelled, it will typically result in a compile-time error.)
Invoking this method will result in the creation of the returned node and its ancestors if they do not already exist. If the returned node did not exist prior to this call, this node and any ancestors that were created by this call are not guaranteed to become permanent until the flush method is called on the returned node (or one of its ancestors or descendants).
c - the class for whose package a user preference node is desired. - java.lang.Class
returns: the user preference node associated with the package of which
c is a member. - java.util.prefs.Preferences
throws: java.lang.NullPointerException - if c is null.
Returns the preference node from the calling user's preference tree
that is associated (by convention) with the specified class's package.
The convention is as follows: the absolute path name of the node is the
fully qualified package name, preceded by a slash ('/'), and
with each period ('.') replaced by a slash. For example the
absolute path name of the node associated with the class
com.acme.widget.Foo is /com/acme/widget.
This convention does not apply to the unnamed package, whose
associated preference node is <unnamed>. This node
is not intended for long term use, but for convenience in the early
development of programs that do not yet belong to a package, and
for "throwaway" programs. Valuable data should not be stored
at this node as it is shared by all programs that use it.
A class Foo wishing to access preferences pertaining to its
package can obtain a preference node as follows:
static Preferences prefs = Preferences.userNodeForPackage(Foo.class);
This idiom obviates the need for using a string to describe the
preferences node and decreases the likelihood of a run-time failure.
(If the class name is misspelled, it will typically result in a
compile-time error.)
Invoking this method will result in the creation of the returned
node and its ancestors if they do not already exist. If the returned
node did not exist prior to this call, this node and any ancestors that
were created by this call are not guaranteed to become permanent until
the flush method is called on the returned node (or one of its
ancestors or descendants).
c - the class for whose package a user preference node is desired. - `java.lang.Class`
returns: the user preference node associated with the package of which
c is a member. - `java.util.prefs.Preferences`
throws: java.lang.NullPointerException - if c is null.*user-rootclj
(*user-root)Returns the root preference node for the calling user.
returns: the root preference node for the calling user. - java.util.prefs.Preferences
throws: java.lang.SecurityException - If a security manager is present and it denies RuntimePermission("preferences").
Returns the root preference node for the calling user.
returns: the root preference node for the calling user. - `java.util.prefs.Preferences`
throws: java.lang.SecurityException - If a security manager is present and it denies RuntimePermission("preferences").absolute-pathclj
(absolute-path this)Returns this preference node's absolute path name.
returns: this preference node's absolute path name. - java.lang.String
Returns this preference node's absolute path name. returns: this preference node's absolute path name. - `java.lang.String`
add-node-change-listenerclj
(add-node-change-listener this ncl)Registers the specified listener to receive node change events for this node. A node change event is generated when a child node is added to or removed from this node. (A single removeNode() invocation results in multiple node change events, one for every node in the subtree rooted at the removed node.)
Events are only guaranteed for changes made within the same JVM as the registered listener, though some implementations may generate events for changes made outside this JVM. Events may be generated before the changes have become permanent. Events are not generated when indirect descendants of this node are added or removed; a caller desiring such events must register with each descendant.
Few guarantees can be made regarding node creation. Because nodes are created implicitly upon access, it may not be feasible for an implementation to determine whether a child node existed in the backing store prior to access (for example, because the backing store is unreachable or cached information is out of date). Under these circumstances, implementations are neither required to generate node change events nor prohibited from doing so.
ncl - The NodeChangeListener to add. - java.util.prefs.NodeChangeListener
throws: java.lang.NullPointerException - if ncl is null.
Registers the specified listener to receive node change events for this node. A node change event is generated when a child node is added to or removed from this node. (A single removeNode() invocation results in multiple node change events, one for every node in the subtree rooted at the removed node.) Events are only guaranteed for changes made within the same JVM as the registered listener, though some implementations may generate events for changes made outside this JVM. Events may be generated before the changes have become permanent. Events are not generated when indirect descendants of this node are added or removed; a caller desiring such events must register with each descendant. Few guarantees can be made regarding node creation. Because nodes are created implicitly upon access, it may not be feasible for an implementation to determine whether a child node existed in the backing store prior to access (for example, because the backing store is unreachable or cached information is out of date). Under these circumstances, implementations are neither required to generate node change events nor prohibited from doing so. ncl - The NodeChangeListener to add. - `java.util.prefs.NodeChangeListener` throws: java.lang.NullPointerException - if ncl is null.
add-preference-change-listenerclj
(add-preference-change-listener this pcl)Registers the specified listener to receive preference change events for this preference node. A preference change event is generated when a preference is added to this node, removed from this node, or when the value associated with a preference is changed. (Preference change events are not generated by the removeNode() method, which generates a node change event. Preference change events are generated by the clear method.)
Events are only guaranteed for changes made within the same JVM as the registered listener, though some implementations may generate events for changes made outside this JVM. Events may be generated before the changes have been made persistent. Events are not generated when preferences are modified in descendants of this node; a caller desiring such events must register with each descendant.
pcl - The preference change listener to add. - java.util.prefs.PreferenceChangeListener
throws: java.lang.NullPointerException - if pcl is null.
Registers the specified listener to receive preference change events for this preference node. A preference change event is generated when a preference is added to this node, removed from this node, or when the value associated with a preference is changed. (Preference change events are not generated by the removeNode() method, which generates a node change event. Preference change events are generated by the clear method.) Events are only guaranteed for changes made within the same JVM as the registered listener, though some implementations may generate events for changes made outside this JVM. Events may be generated before the changes have been made persistent. Events are not generated when preferences are modified in descendants of this node; a caller desiring such events must register with each descendant. pcl - The preference change listener to add. - `java.util.prefs.PreferenceChangeListener` throws: java.lang.NullPointerException - if pcl is null.
children-namesclj
(children-names this)Returns the names of the children of this preference node, relative to this node. (The returned array will be of size zero if this node has no children.)
returns: the names of the children of this preference node. - java.lang.String[]
throws: java.util.prefs.BackingStoreException - if this operation cannot be completed due to a failure in the backing store, or inability to communicate with it.
Returns the names of the children of this preference node, relative to this node. (The returned array will be of size zero if this node has no children.) returns: the names of the children of this preference node. - `java.lang.String[]` throws: java.util.prefs.BackingStoreException - if this operation cannot be completed due to a failure in the backing store, or inability to communicate with it.
clearclj
(clear this)Removes all of the preferences (key-value associations) in this preference node. This call has no effect on any descendants of this node.
If this implementation supports stored defaults, and this node in the preferences hierarchy contains any such defaults, the stored defaults will be "exposed" by this call, in the sense that they will be returned by succeeding calls to get.
throws: java.util.prefs.BackingStoreException - if this operation cannot be completed due to a failure in the backing store, or inability to communicate with it.
Removes all of the preferences (key-value associations) in this preference node. This call has no effect on any descendants of this node. If this implementation supports stored defaults, and this node in the preferences hierarchy contains any such defaults, the stored defaults will be "exposed" by this call, in the sense that they will be returned by succeeding calls to get. throws: java.util.prefs.BackingStoreException - if this operation cannot be completed due to a failure in the backing store, or inability to communicate with it.
export-nodeclj
(export-node this os)Emits on the specified output stream an XML document representing all of the preferences contained in this node (but not its descendants). This XML document is, in effect, an offline backup of the node.
The XML document will have the following DOCTYPE declaration:
<!DOCTYPE preferences SYSTEM "http://java.sun.com/dtd/preferences.dtd">
The UTF-8 character encoding will be used.
This method is an exception to the general rule that the results of concurrently executing multiple methods in this class yields results equivalent to some serial execution. If the preferences at this node are modified concurrently with an invocation of this method, the exported preferences comprise a "fuzzy snapshot" of the preferences contained in the node; some of the concurrent modifications may be reflected in the exported data while others may not.
os - the output stream on which to emit the XML document. - java.io.OutputStream
throws: java.io.IOException - if writing to the specified output stream results in an IOException.
Emits on the specified output stream an XML document representing all of the preferences contained in this node (but not its descendants). This XML document is, in effect, an offline backup of the node. The XML document will have the following DOCTYPE declaration: <!DOCTYPE preferences SYSTEM "http://java.sun.com/dtd/preferences.dtd"> The UTF-8 character encoding will be used. This method is an exception to the general rule that the results of concurrently executing multiple methods in this class yields results equivalent to some serial execution. If the preferences at this node are modified concurrently with an invocation of this method, the exported preferences comprise a "fuzzy snapshot" of the preferences contained in the node; some of the concurrent modifications may be reflected in the exported data while others may not. os - the output stream on which to emit the XML document. - `java.io.OutputStream` throws: java.io.IOException - if writing to the specified output stream results in an IOException.
export-subtreeclj
(export-subtree this os)Emits an XML document representing all of the preferences contained in this node and all of its descendants. This XML document is, in effect, an offline backup of the subtree rooted at the node.
The XML document will have the following DOCTYPE declaration:
<!DOCTYPE preferences SYSTEM "http://java.sun.com/dtd/preferences.dtd">
The UTF-8 character encoding will be used.
This method is an exception to the general rule that the results of concurrently executing multiple methods in this class yields results equivalent to some serial execution. If the preferences or nodes in the subtree rooted at this node are modified concurrently with an invocation of this method, the exported preferences comprise a "fuzzy snapshot" of the subtree; some of the concurrent modifications may be reflected in the exported data while others may not.
os - the output stream on which to emit the XML document. - java.io.OutputStream
throws: java.io.IOException - if writing to the specified output stream results in an IOException.
Emits an XML document representing all of the preferences contained in this node and all of its descendants. This XML document is, in effect, an offline backup of the subtree rooted at the node. The XML document will have the following DOCTYPE declaration: <!DOCTYPE preferences SYSTEM "http://java.sun.com/dtd/preferences.dtd"> The UTF-8 character encoding will be used. This method is an exception to the general rule that the results of concurrently executing multiple methods in this class yields results equivalent to some serial execution. If the preferences or nodes in the subtree rooted at this node are modified concurrently with an invocation of this method, the exported preferences comprise a "fuzzy snapshot" of the subtree; some of the concurrent modifications may be reflected in the exported data while others may not. os - the output stream on which to emit the XML document. - `java.io.OutputStream` throws: java.io.IOException - if writing to the specified output stream results in an IOException.
flushclj
(flush this)Forces any changes in the contents of this preference node and its descendants to the persistent store. Once this method returns successfully, it is safe to assume that all changes made in the subtree rooted at this node prior to the method invocation have become permanent.
Implementations are free to flush changes into the persistent store at any time. They do not need to wait for this method to be called.
When a flush occurs on a newly created node, it is made persistent, as are any ancestors (and descendants) that have yet to be made persistent. Note however that any preference value changes in ancestors are not guaranteed to be made persistent.
If this method is invoked on a node that has been removed with the removeNode() method, flushSpi() is invoked on this node, but not on others.
throws: java.util.prefs.BackingStoreException - if this operation cannot be completed due to a failure in the backing store, or inability to communicate with it.
Forces any changes in the contents of this preference node and its descendants to the persistent store. Once this method returns successfully, it is safe to assume that all changes made in the subtree rooted at this node prior to the method invocation have become permanent. Implementations are free to flush changes into the persistent store at any time. They do not need to wait for this method to be called. When a flush occurs on a newly created node, it is made persistent, as are any ancestors (and descendants) that have yet to be made persistent. Note however that any preference value changes in ancestors are not guaranteed to be made persistent. If this method is invoked on a node that has been removed with the removeNode() method, flushSpi() is invoked on this node, but not on others. throws: java.util.prefs.BackingStoreException - if this operation cannot be completed due to a failure in the backing store, or inability to communicate with it.
getclj
(get this key def)Returns the value associated with the specified key in this preference node. Returns the specified default if there is no value associated with the key, or the backing store is inaccessible.
Some implementations may store default values in their backing stores. If there is no value associated with the specified key but there is such a stored default, it is returned in preference to the specified default.
key - key whose associated value is to be returned. - java.lang.String
def - the value to be returned in the event that this preference node has no value associated with key. - java.lang.String
returns: the value associated with key, or def
if no value is associated with key, or the backing
store is inaccessible. - java.lang.String
throws: java.lang.IllegalStateException - if this node (or an ancestor) has been removed with the removeNode() method.
Returns the value associated with the specified key in this preference
node. Returns the specified default if there is no value associated
with the key, or the backing store is inaccessible.
Some implementations may store default values in their backing
stores. If there is no value associated with the specified key
but there is such a stored default, it is returned in
preference to the specified default.
key - key whose associated value is to be returned. - `java.lang.String`
def - the value to be returned in the event that this preference node has no value associated with key. - `java.lang.String`
returns: the value associated with key, or def
if no value is associated with key, or the backing
store is inaccessible. - `java.lang.String`
throws: java.lang.IllegalStateException - if this node (or an ancestor) has been removed with the removeNode() method.get-boolean?clj
(get-boolean? this key def)Returns the boolean value represented by the string associated with the specified key in this preference node. Valid strings are "true", which represents true, and "false", which represents false. Case is ignored, so, for example, "TRUE" and "False" are also valid. This method is intended for use in conjunction with putBoolean(java.lang.String, boolean).
Returns the specified default if there is no value associated with the key, the backing store is inaccessible, or if the associated value is something other than "true" or "false", ignoring case.
If the implementation supports stored defaults and such a default exists and is accessible, it is used in preference to the specified default, unless the stored default is something other than "true" or "false", ignoring case, in which case the specified default is used.
key - key whose associated value is to be returned as a boolean. - java.lang.String
def - the value to be returned in the event that this preference node has no value associated with key or the associated value cannot be interpreted as a boolean, or the backing store is inaccessible. - boolean
returns: the boolean value represented by the string associated with
key in this preference node, or def if the
associated value does not exist or cannot be interpreted as
a boolean. - boolean
throws: java.lang.IllegalStateException - if this node (or an ancestor) has been removed with the removeNode() method.
Returns the boolean value represented by the string associated with the
specified key in this preference node. Valid strings
are "true", which represents true, and "false", which
represents false. Case is ignored, so, for example, "TRUE"
and "False" are also valid. This method is intended for use in
conjunction with putBoolean(java.lang.String, boolean).
Returns the specified default if there is no value
associated with the key, the backing store is inaccessible, or if the
associated value is something other than "true" or
"false", ignoring case.
If the implementation supports stored defaults and such a
default exists and is accessible, it is used in preference to the
specified default, unless the stored default is something other than
"true" or "false", ignoring case, in which case the
specified default is used.
key - key whose associated value is to be returned as a boolean. - `java.lang.String`
def - the value to be returned in the event that this preference node has no value associated with key or the associated value cannot be interpreted as a boolean, or the backing store is inaccessible. - `boolean`
returns: the boolean value represented by the string associated with
key in this preference node, or def if the
associated value does not exist or cannot be interpreted as
a boolean. - `boolean`
throws: java.lang.IllegalStateException - if this node (or an ancestor) has been removed with the removeNode() method.get-byte-arrayclj
(get-byte-array this key def)Returns the byte array value represented by the string associated with the specified key in this preference node. Valid strings are Base64 encoded binary data, as defined in RFC 2045, Section 6.8, with one minor change: the string must consist solely of characters from the Base64 Alphabet; no newline characters or extraneous characters are permitted. This method is intended for use in conjunction with putByteArray(java.lang.String, byte[]).
Returns the specified default if there is no value associated with the key, the backing store is inaccessible, or if the associated value is not a valid Base64 encoded byte array (as defined above).
If the implementation supports stored defaults and such a default exists and is accessible, it is used in preference to the specified default, unless the stored default is not a valid Base64 encoded byte array (as defined above), in which case the specified default is used.
key - key whose associated value is to be returned as a byte array. - java.lang.String
def - the value to be returned in the event that this preference node has no value associated with key or the associated value cannot be interpreted as a byte array, or the backing store is inaccessible. - byte[]
returns: the byte array value represented by the string associated with
key in this preference node, or def if the
associated value does not exist or cannot be interpreted as
a byte array. - byte[]
throws: java.lang.IllegalStateException - if this node (or an ancestor) has been removed with the removeNode() method.
Returns the byte array value represented by the string associated with
the specified key in this preference node. Valid strings are
Base64 encoded binary data, as defined in RFC 2045, Section 6.8,
with one minor change: the string must consist solely of characters
from the Base64 Alphabet; no newline characters or
extraneous characters are permitted. This method is intended for use
in conjunction with putByteArray(java.lang.String, byte[]).
Returns the specified default if there is no value
associated with the key, the backing store is inaccessible, or if the
associated value is not a valid Base64 encoded byte array
(as defined above).
If the implementation supports stored defaults and such a
default exists and is accessible, it is used in preference to the
specified default, unless the stored default is not a valid Base64
encoded byte array (as defined above), in which case the
specified default is used.
key - key whose associated value is to be returned as a byte array. - `java.lang.String`
def - the value to be returned in the event that this preference node has no value associated with key or the associated value cannot be interpreted as a byte array, or the backing store is inaccessible. - `byte[]`
returns: the byte array value represented by the string associated with
key in this preference node, or def if the
associated value does not exist or cannot be interpreted as
a byte array. - `byte[]`
throws: java.lang.IllegalStateException - if this node (or an ancestor) has been removed with the removeNode() method.get-doubleclj
(get-double this key def)Returns the double value represented by the string associated with the specified key in this preference node. The string is converted to an integer as by Double.parseDouble(String). Returns the specified default if there is no value associated with the key, the backing store is inaccessible, or if Double.parseDouble(String) would throw a NumberFormatException if the associated value were passed. This method is intended for use in conjunction with putDouble(java.lang.String, double).
If the implementation supports stored defaults and such a default exists, is accessible, and could be converted to a double with Double.parseDouble, this double is returned in preference to the specified default.
key - key whose associated value is to be returned as a double. - java.lang.String
def - the value to be returned in the event that this preference node has no value associated with key or the associated value cannot be interpreted as a double, or the backing store is inaccessible. - double
returns: the double value represented by the string associated with
key in this preference node, or def if the
associated value does not exist or cannot be interpreted as
a double. - double
throws: java.lang.IllegalStateException - if this node (or an ancestor) has been removed with the removeNode() method.
Returns the double value represented by the string associated with the
specified key in this preference node. The string is converted to an
integer as by Double.parseDouble(String). Returns the specified
default if there is no value associated with the key, the backing store
is inaccessible, or if Double.parseDouble(String) would throw a
NumberFormatException if the associated value were passed.
This method is intended for use in conjunction with putDouble(java.lang.String, double).
If the implementation supports stored defaults and such a
default exists, is accessible, and could be converted to a double
with Double.parseDouble, this double is returned in preference
to the specified default.
key - key whose associated value is to be returned as a double. - `java.lang.String`
def - the value to be returned in the event that this preference node has no value associated with key or the associated value cannot be interpreted as a double, or the backing store is inaccessible. - `double`
returns: the double value represented by the string associated with
key in this preference node, or def if the
associated value does not exist or cannot be interpreted as
a double. - `double`
throws: java.lang.IllegalStateException - if this node (or an ancestor) has been removed with the removeNode() method.get-floatclj
(get-float this key def)Returns the float value represented by the string associated with the specified key in this preference node. The string is converted to an integer as by Float.parseFloat(String). Returns the specified default if there is no value associated with the key, the backing store is inaccessible, or if Float.parseFloat(String) would throw a NumberFormatException if the associated value were passed. This method is intended for use in conjunction with putFloat(java.lang.String, float).
If the implementation supports stored defaults and such a default exists, is accessible, and could be converted to a float with Float.parseFloat, this float is returned in preference to the specified default.
key - key whose associated value is to be returned as a float. - java.lang.String
def - the value to be returned in the event that this preference node has no value associated with key or the associated value cannot be interpreted as a float, or the backing store is inaccessible. - float
returns: the float value represented by the string associated with
key in this preference node, or def if the
associated value does not exist or cannot be interpreted as
a float. - float
throws: java.lang.IllegalStateException - if this node (or an ancestor) has been removed with the removeNode() method.
Returns the float value represented by the string associated with the
specified key in this preference node. The string is converted to an
integer as by Float.parseFloat(String). Returns the specified
default if there is no value associated with the key, the backing store
is inaccessible, or if Float.parseFloat(String) would throw a
NumberFormatException if the associated value were passed.
This method is intended for use in conjunction with putFloat(java.lang.String, float).
If the implementation supports stored defaults and such a
default exists, is accessible, and could be converted to a float
with Float.parseFloat, this float is returned in preference to
the specified default.
key - key whose associated value is to be returned as a float. - `java.lang.String`
def - the value to be returned in the event that this preference node has no value associated with key or the associated value cannot be interpreted as a float, or the backing store is inaccessible. - `float`
returns: the float value represented by the string associated with
key in this preference node, or def if the
associated value does not exist or cannot be interpreted as
a float. - `float`
throws: java.lang.IllegalStateException - if this node (or an ancestor) has been removed with the removeNode() method.get-intclj
(get-int this key def)Returns the int value represented by the string associated with the specified key in this preference node. The string is converted to an integer as by Integer.parseInt(String). Returns the specified default if there is no value associated with the key, the backing store is inaccessible, or if Integer.parseInt(String) would throw a NumberFormatException if the associated value were passed. This method is intended for use in conjunction with putInt(java.lang.String, int).
If the implementation supports stored defaults and such a default exists, is accessible, and could be converted to an int with Integer.parseInt, this int is returned in preference to the specified default.
key - key whose associated value is to be returned as an int. - java.lang.String
def - the value to be returned in the event that this preference node has no value associated with key or the associated value cannot be interpreted as an int, or the backing store is inaccessible. - int
returns: the int value represented by the string associated with
key in this preference node, or def if the
associated value does not exist or cannot be interpreted as
an int. - int
throws: java.lang.IllegalStateException - if this node (or an ancestor) has been removed with the removeNode() method.
Returns the int value represented by the string associated with the
specified key in this preference node. The string is converted to
an integer as by Integer.parseInt(String). Returns the
specified default if there is no value associated with the key,
the backing store is inaccessible, or if
Integer.parseInt(String) would throw a NumberFormatException if the associated value were passed. This
method is intended for use in conjunction with putInt(java.lang.String, int).
If the implementation supports stored defaults and such a
default exists, is accessible, and could be converted to an int
with Integer.parseInt, this int is returned in preference to
the specified default.
key - key whose associated value is to be returned as an int. - `java.lang.String`
def - the value to be returned in the event that this preference node has no value associated with key or the associated value cannot be interpreted as an int, or the backing store is inaccessible. - `int`
returns: the int value represented by the string associated with
key in this preference node, or def if the
associated value does not exist or cannot be interpreted as
an int. - `int`
throws: java.lang.IllegalStateException - if this node (or an ancestor) has been removed with the removeNode() method.get-longclj
(get-long this key def)Returns the long value represented by the string associated with the specified key in this preference node. The string is converted to a long as by Long.parseLong(String). Returns the specified default if there is no value associated with the key, the backing store is inaccessible, or if Long.parseLong(String) would throw a NumberFormatException if the associated value were passed. This method is intended for use in conjunction with putLong(java.lang.String, long).
If the implementation supports stored defaults and such a default exists, is accessible, and could be converted to a long with Long.parseLong, this long is returned in preference to the specified default.
key - key whose associated value is to be returned as a long. - java.lang.String
def - the value to be returned in the event that this preference node has no value associated with key or the associated value cannot be interpreted as a long, or the backing store is inaccessible. - long
returns: the long value represented by the string associated with
key in this preference node, or def if the
associated value does not exist or cannot be interpreted as
a long. - long
throws: java.lang.IllegalStateException - if this node (or an ancestor) has been removed with the removeNode() method.
Returns the long value represented by the string associated with the
specified key in this preference node. The string is converted to
a long as by Long.parseLong(String). Returns the
specified default if there is no value associated with the key,
the backing store is inaccessible, or if
Long.parseLong(String) would throw a NumberFormatException if the associated value were passed. This
method is intended for use in conjunction with putLong(java.lang.String, long).
If the implementation supports stored defaults and such a
default exists, is accessible, and could be converted to a long
with Long.parseLong, this long is returned in preference to
the specified default.
key - key whose associated value is to be returned as a long. - `java.lang.String`
def - the value to be returned in the event that this preference node has no value associated with key or the associated value cannot be interpreted as a long, or the backing store is inaccessible. - `long`
returns: the long value represented by the string associated with
key in this preference node, or def if the
associated value does not exist or cannot be interpreted as
a long. - `long`
throws: java.lang.IllegalStateException - if this node (or an ancestor) has been removed with the removeNode() method.keysclj
(keys this)Returns all of the keys that have an associated value in this preference node. (The returned array will be of size zero if this node has no preferences.)
If the implementation supports stored defaults and there are any such defaults at this node that have not been overridden, by explicit preferences, the defaults are returned in the array in addition to any explicit preferences.
returns: an array of the keys that have an associated value in this
preference node. - java.lang.String[]
throws: java.util.prefs.BackingStoreException - if this operation cannot be completed due to a failure in the backing store, or inability to communicate with it.
Returns all of the keys that have an associated value in this
preference node. (The returned array will be of size zero if
this node has no preferences.)
If the implementation supports stored defaults and there
are any such defaults at this node that have not been overridden,
by explicit preferences, the defaults are returned in the array in
addition to any explicit preferences.
returns: an array of the keys that have an associated value in this
preference node. - `java.lang.String[]`
throws: java.util.prefs.BackingStoreException - if this operation cannot be completed due to a failure in the backing store, or inability to communicate with it.nameclj
(name this)Returns this preference node's name, relative to its parent.
returns: this preference node's name, relative to its parent. - java.lang.String
Returns this preference node's name, relative to its parent. returns: this preference node's name, relative to its parent. - `java.lang.String`
nodeclj
(node this path-name)Returns the named preference node in the same tree as this node, creating it and any of its ancestors if they do not already exist. Accepts a relative or absolute path name. Relative path names (which do not begin with the slash character ('/')) are interpreted relative to this preference node.
If the returned node did not exist prior to this call, this node and any ancestors that were created by this call are not guaranteed to become permanent until the flush method is called on the returned node (or one of its ancestors or descendants).
path-name - the path name of the preference node to return. - java.lang.String
returns: the specified preference node. - java.util.prefs.Preferences
throws: java.lang.IllegalArgumentException - if the path name is invalid (i.e., it contains multiple consecutive slash characters, or ends with a slash character and is more than one character long).
Returns the named preference node in the same tree as this node,
creating it and any of its ancestors if they do not already exist.
Accepts a relative or absolute path name. Relative path names
(which do not begin with the slash character ('/')) are
interpreted relative to this preference node.
If the returned node did not exist prior to this call, this node and
any ancestors that were created by this call are not guaranteed
to become permanent until the flush method is called on
the returned node (or one of its ancestors or descendants).
path-name - the path name of the preference node to return. - `java.lang.String`
returns: the specified preference node. - `java.util.prefs.Preferences`
throws: java.lang.IllegalArgumentException - if the path name is invalid (i.e., it contains multiple consecutive slash characters, or ends with a slash character and is more than one character long).node-existsclj
(node-exists this path-name)Returns true if the named preference node exists in the same tree as this node. Relative path names (which do not begin with the slash character ('/')) are interpreted relative to this preference node.
If this node (or an ancestor) has already been removed with the removeNode() method, it is legal to invoke this method, but only with the path name ""; the invocation will return false. Thus, the idiom p.nodeExists("") may be used to test whether p has been removed.
path-name - the path name of the node whose existence is to be checked. - java.lang.String
returns: true if the specified node exists. - boolean
throws: java.util.prefs.BackingStoreException - if this operation cannot be completed due to a failure in the backing store, or inability to communicate with it.
Returns true if the named preference node exists in the same tree
as this node. Relative path names (which do not begin with the slash
character ('/')) are interpreted relative to this preference
node.
If this node (or an ancestor) has already been removed with the
removeNode() method, it is legal to invoke this method,
but only with the path name ""; the invocation will return
false. Thus, the idiom p.nodeExists("") may be
used to test whether p has been removed.
path-name - the path name of the node whose existence is to be checked. - `java.lang.String`
returns: true if the specified node exists. - `boolean`
throws: java.util.prefs.BackingStoreException - if this operation cannot be completed due to a failure in the backing store, or inability to communicate with it.parentclj
(parent this)Returns the parent of this preference node, or null if this is the root.
returns: the parent of this preference node. - java.util.prefs.Preferences
throws: java.lang.IllegalStateException - if this node (or an ancestor) has been removed with the removeNode() method.
Returns the parent of this preference node, or null if this is the root. returns: the parent of this preference node. - `java.util.prefs.Preferences` throws: java.lang.IllegalStateException - if this node (or an ancestor) has been removed with the removeNode() method.
putclj
(put this key value)Associates the specified value with the specified key in this preference node.
key - key with which the specified value is to be associated. - java.lang.String
value - value to be associated with the specified key. - java.lang.String
throws: java.lang.NullPointerException - if key or value is null.
Associates the specified value with the specified key in this preference node. key - key with which the specified value is to be associated. - `java.lang.String` value - value to be associated with the specified key. - `java.lang.String` throws: java.lang.NullPointerException - if key or value is null.
put-booleanclj
(put-boolean this key value)Associates a string representing the specified boolean value with the specified key in this preference node. The associated string is "true" if the value is true, and "false" if it is false. This method is intended for use in conjunction with getBoolean(java.lang.String, boolean).
key - key with which the string form of value is to be associated. - java.lang.String
value - value whose string form is to be associated with key. - boolean
throws: java.lang.NullPointerException - if key is null.
Associates a string representing the specified boolean value with the specified key in this preference node. The associated string is "true" if the value is true, and "false" if it is false. This method is intended for use in conjunction with getBoolean(java.lang.String, boolean). key - key with which the string form of value is to be associated. - `java.lang.String` value - value whose string form is to be associated with key. - `boolean` throws: java.lang.NullPointerException - if key is null.
put-byte-arrayclj
(put-byte-array this key value)Associates a string representing the specified byte array with the specified key in this preference node. The associated string is the Base64 encoding of the byte array, as defined in RFC 2045, Section 6.8, with one minor change: the string will consist solely of characters from the Base64 Alphabet; it will not contain any newline characters. Note that the maximum length of the byte array is limited to three quarters of MAX_VALUE_LENGTH so that the length of the Base64 encoded String does not exceed MAX_VALUE_LENGTH. This method is intended for use in conjunction with getByteArray(java.lang.String, byte[]).
key - key with which the string form of value is to be associated. - java.lang.String
value - value whose string form is to be associated with key. - byte[]
throws: java.lang.NullPointerException - if key or value is null.
Associates a string representing the specified byte array with the specified key in this preference node. The associated string is the Base64 encoding of the byte array, as defined in RFC 2045, Section 6.8, with one minor change: the string will consist solely of characters from the Base64 Alphabet; it will not contain any newline characters. Note that the maximum length of the byte array is limited to three quarters of MAX_VALUE_LENGTH so that the length of the Base64 encoded String does not exceed MAX_VALUE_LENGTH. This method is intended for use in conjunction with getByteArray(java.lang.String, byte[]). key - key with which the string form of value is to be associated. - `java.lang.String` value - value whose string form is to be associated with key. - `byte[]` throws: java.lang.NullPointerException - if key or value is null.
put-doubleclj
(put-double this key value)Associates a string representing the specified double value with the specified key in this preference node. The associated string is the one that would be returned if the double value were passed to Double.toString(double). This method is intended for use in conjunction with getDouble(java.lang.String, double).
key - key with which the string form of value is to be associated. - java.lang.String
value - value whose string form is to be associated with key. - double
throws: java.lang.NullPointerException - if key is null.
Associates a string representing the specified double value with the specified key in this preference node. The associated string is the one that would be returned if the double value were passed to Double.toString(double). This method is intended for use in conjunction with getDouble(java.lang.String, double). key - key with which the string form of value is to be associated. - `java.lang.String` value - value whose string form is to be associated with key. - `double` throws: java.lang.NullPointerException - if key is null.
put-floatclj
(put-float this key value)Associates a string representing the specified float value with the specified key in this preference node. The associated string is the one that would be returned if the float value were passed to Float.toString(float). This method is intended for use in conjunction with getFloat(java.lang.String, float).
key - key with which the string form of value is to be associated. - java.lang.String
value - value whose string form is to be associated with key. - float
throws: java.lang.NullPointerException - if key is null.
Associates a string representing the specified float value with the specified key in this preference node. The associated string is the one that would be returned if the float value were passed to Float.toString(float). This method is intended for use in conjunction with getFloat(java.lang.String, float). key - key with which the string form of value is to be associated. - `java.lang.String` value - value whose string form is to be associated with key. - `float` throws: java.lang.NullPointerException - if key is null.
put-intclj
(put-int this key value)Associates a string representing the specified int value with the specified key in this preference node. The associated string is the one that would be returned if the int value were passed to Integer.toString(int). This method is intended for use in conjunction with getInt(java.lang.String, int).
key - key with which the string form of value is to be associated. - java.lang.String
value - value whose string form is to be associated with key. - int
throws: java.lang.NullPointerException - if key is null.
Associates a string representing the specified int value with the specified key in this preference node. The associated string is the one that would be returned if the int value were passed to Integer.toString(int). This method is intended for use in conjunction with getInt(java.lang.String, int). key - key with which the string form of value is to be associated. - `java.lang.String` value - value whose string form is to be associated with key. - `int` throws: java.lang.NullPointerException - if key is null.
put-longclj
(put-long this key value)Associates a string representing the specified long value with the specified key in this preference node. The associated string is the one that would be returned if the long value were passed to Long.toString(long). This method is intended for use in conjunction with getLong(java.lang.String, long).
key - key with which the string form of value is to be associated. - java.lang.String
value - value whose string form is to be associated with key. - long
throws: java.lang.NullPointerException - if key is null.
Associates a string representing the specified long value with the specified key in this preference node. The associated string is the one that would be returned if the long value were passed to Long.toString(long). This method is intended for use in conjunction with getLong(java.lang.String, long). key - key with which the string form of value is to be associated. - `java.lang.String` value - value whose string form is to be associated with key. - `long` throws: java.lang.NullPointerException - if key is null.
removeclj
(remove this key)Removes the value associated with the specified key in this preference node, if any.
If this implementation supports stored defaults, and there is such a default for the specified preference, the stored default will be "exposed" by this call, in the sense that it will be returned by a succeeding call to get.
key - key whose mapping is to be removed from the preference node. - java.lang.String
throws: java.lang.NullPointerException - if key is null.
Removes the value associated with the specified key in this preference node, if any. If this implementation supports stored defaults, and there is such a default for the specified preference, the stored default will be "exposed" by this call, in the sense that it will be returned by a succeeding call to get. key - key whose mapping is to be removed from the preference node. - `java.lang.String` throws: java.lang.NullPointerException - if key is null.
remove-nodeclj
(remove-node this)Removes this preference node and all of its descendants, invalidating any preferences contained in the removed nodes. Once a node has been removed, attempting any method other than name(), absolutePath(), isUserNode(), flush() or nodeExists("") on the corresponding Preferences instance will fail with an IllegalStateException. (The methods defined on Object can still be invoked on a node after it has been removed; they will not throw IllegalStateException.)
The removal is not guaranteed to be persistent until the flush method is called on this node (or an ancestor).
If this implementation supports stored defaults, removing a node exposes any stored defaults at or below this node. Thus, a subsequent call to nodeExists on this node's path name may return true, and a subsequent call to node on this path name may return a (different) Preferences instance representing a non-empty collection of preferences and/or children.
throws: java.util.prefs.BackingStoreException - if this operation cannot be completed due to a failure in the backing store, or inability to communicate with it.
Removes this preference node and all of its descendants, invalidating
any preferences contained in the removed nodes. Once a node has been
removed, attempting any method other than name(),
absolutePath(), isUserNode(), flush() or
nodeExists("") on the corresponding
Preferences instance will fail with an
IllegalStateException. (The methods defined on Object
can still be invoked on a node after it has been removed; they will not
throw IllegalStateException.)
The removal is not guaranteed to be persistent until the
flush method is called on this node (or an ancestor).
If this implementation supports stored defaults, removing a
node exposes any stored defaults at or below this node. Thus, a
subsequent call to nodeExists on this node's path name may
return true, and a subsequent call to node on this
path name may return a (different) Preferences instance
representing a non-empty collection of preferences and/or children.
throws: java.util.prefs.BackingStoreException - if this operation cannot be completed due to a failure in the backing store, or inability to communicate with it.remove-node-change-listenerclj
(remove-node-change-listener this ncl)Removes the specified NodeChangeListener, so it no longer receives change events.
ncl - The NodeChangeListener to remove. - java.util.prefs.NodeChangeListener
throws: java.lang.IllegalArgumentException - if ncl was not a registered NodeChangeListener on this node.
Removes the specified NodeChangeListener, so it no longer receives change events. ncl - The NodeChangeListener to remove. - `java.util.prefs.NodeChangeListener` throws: java.lang.IllegalArgumentException - if ncl was not a registered NodeChangeListener on this node.
remove-preference-change-listenerclj
(remove-preference-change-listener this pcl)Removes the specified preference change listener, so it no longer receives preference change events.
pcl - The preference change listener to remove. - java.util.prefs.PreferenceChangeListener
throws: java.lang.IllegalArgumentException - if pcl was not a registered preference change listener on this node.
Removes the specified preference change listener, so it no longer receives preference change events. pcl - The preference change listener to remove. - `java.util.prefs.PreferenceChangeListener` throws: java.lang.IllegalArgumentException - if pcl was not a registered preference change listener on this node.
syncclj
(sync this)Ensures that future reads from this preference node and its descendants reflect any changes that were committed to the persistent store (from any VM) prior to the sync invocation. As a side-effect, forces any changes in the contents of this preference node and its descendants to the persistent store, as if the flush method had been invoked on this node.
throws: java.util.prefs.BackingStoreException - if this operation cannot be completed due to a failure in the backing store, or inability to communicate with it.
Ensures that future reads from this preference node and its descendants reflect any changes that were committed to the persistent store (from any VM) prior to the sync invocation. As a side-effect, forces any changes in the contents of this preference node and its descendants to the persistent store, as if the flush method had been invoked on this node. throws: java.util.prefs.BackingStoreException - if this operation cannot be completed due to a failure in the backing store, or inability to communicate with it.
to-stringclj
(to-string this)Returns a string representation of this preferences node, as if computed by the expression:(this.isUserNode() ? "User" : "System") " Preference Node: " this.absolutePath().
returns: a string representation of the object. - java.lang.String
Returns a string representation of this preferences node, as if computed by the expression:(this.isUserNode() ? "User" : "System") " Preference Node: " this.absolutePath(). returns: a string representation of the object. - `java.lang.String`
user-node?clj
(user-node? this)Returns true if this preference node is in the user preference tree, false if it's in the system preference tree.
returns: true if this preference node is in the user
preference tree, false if it's in the system
preference tree. - boolean
Returns true if this preference node is in the user
preference tree, false if it's in the system preference tree.
returns: true if this preference node is in the user
preference tree, false if it's in the system
preference tree. - `boolean`cljdoc is a website building & hosting documentation for Clojure/Script libraries
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