javax.swing.text.AbstractDocument — clojure-interop/javax.swing 1.0.5

An implementation of the document interface to serve as a basis for implementing various kinds of documents. At this level there is very little policy, so there is a corresponding increase in difficulty of use.

This class implements a locking mechanism for the document. It allows multiple readers or one writer, and writers must wait until all observers of the document have been notified of a previous change before beginning another mutation to the document. The read lock is acquired and released using the render method. A write lock is acquired by the methods that mutate the document, and are held for the duration of the method call. Notification is done on the thread that produced the mutation, and the thread has full read access to the document for the duration of the notification, but other readers are kept out until the notification has finished. The notification is a beans event notification which does not allow any further mutations until all listeners have been notified.

Any models subclassed from this class and used in conjunction with a text component that has a look and feel implementation that is derived from BasicTextUI may be safely updated asynchronously, because all access to the View hierarchy is serialized by BasicTextUI if the document is of type AbstractDocument. The locking assumes that an independent thread will access the View hierarchy only from the DocumentListener methods, and that there will be only one event thread active at a time.

If concurrency support is desired, there are the following additional implications. The code path for any DocumentListener implementation and any UndoListener implementation must be threadsafe, and not access the component lock if trying to be safe from deadlocks. The repaint and revalidate methods on JComponent are safe.

AbstractDocument models an implied break at the end of the document. Among other things this allows you to position the caret after the last character. As a result of this, getLength returns one less than the length of the Content. If you create your own Content, be sure and initialize it to have an additional character. Refer to StringContent and GapContent for examples of this. Another implication of this is that Elements that model the implied end character will have an endOffset == (getLength() 1). For example, in DefaultStyledDocument getParagraphElement(getLength()).getEndOffset() == getLength() 1 .

Warning: Serialized objects of this class will not be compatible with future Swing releases. The current serialization support is appropriate for short term storage or RMI between applications running the same version of Swing. As of 1.4, support for long term storage of all JavaBeans™ has been added to the java.beans package. Please see XMLEncoder.

*-bidi-element-name clj

Static Constant.

Name of elements used to hold a unidirectional run

type: java.lang.String

*-content-element-name clj

Static Constant.

Name of elements used to represent content

type: java.lang.String

*-element-name-attribute clj

Static Constant.

Name of the attribute used to specify element names.

type: java.lang.String

*-paragraph-element-name clj

Static Constant.

Name of elements used to represent paragraphs

type: java.lang.String

*-section-element-name clj

Static Constant.

Name of elements used to hold sections (lines/paragraphs).

type: java.lang.String

add-document-listener clj

(add-document-listener this listener)

Adds a document listener for notification of any changes.

listener - the DocumentListener to add - javax.swing.event.DocumentListener

add-undoable-edit-listener clj

(add-undoable-edit-listener this listener)

Adds an undo listener for notification of any changes. Undo/Redo operations performed on the UndoableEdit will cause the appropriate DocumentEvent to be fired to keep the view(s) in sync with the model.

listener - the UndoableEditListener to add - javax.swing.event.UndoableEditListener

create-position clj

(create-position this offs)

Returns a position that will track change as the document is altered.

This method is thread safe, although most Swing methods are not. Please see Concurrency in Swing for more information.

offs - the position in the model >= 0 - int

returns: the position - javax.swing.text.Position

throws: javax.swing.text.BadLocationException - if the given position does not represent a valid location in the associated document

dump clj

(dump this out)

Gives a diagnostic dump.

out - the output stream - java.io.PrintStream

get-asynchronous-load-priority clj

(get-asynchronous-load-priority this)

Gets the asynchronous loading priority. If less than zero, the document should not be loaded asynchronously.

returns: the asynchronous loading priority, or -1 if the document should not be loaded asynchronously - int

get-bidi-root-element clj

(get-bidi-root-element this)

Returns the root element of the bidirectional structure for this document. Its children represent character runs with a given Unicode bidi level.

returns: javax.swing.text.Element

get-default-root-element clj

(get-default-root-element this)

Returns the root element that views should be based upon unless some other mechanism for assigning views to element structures is provided.

returns: the root element - javax.swing.text.Element

get-document-filter clj

(get-document-filter this)

Returns the DocumentFilter that is responsible for filtering of insertion/removal. A null return value implies no filtering is to occur.

returns: the DocumentFilter - javax.swing.text.DocumentFilter

get-document-listeners clj

(get-document-listeners this)

Returns an array of all the document listeners registered on this document.

returns: all of this document's DocumentListeners or an empty array if no document listeners are currently registered - javax.swing.event.DocumentListener[]

get-document-properties clj

(get-document-properties this)

Supports managing a set of properties. Callers can use the documentProperties dictionary to annotate the document with document-wide properties.

returns: a non-null Dictionary - java.util.Dictionary<java.lang.Object,java.lang.Object>

get-end-position clj

(get-end-position this)

Returns a position that represents the end of the document. The position returned can be counted on to track change and stay located at the end of the document.

returns: the position - javax.swing.text.Position

get-length clj

(get-length this)

Returns the length of the data. This is the number of characters of content that represents the users data.

returns: the length >= 0 - int

get-listeners clj

(get-listeners this listener-type)

Returns an array of all the objects currently registered as FooListeners upon this document. FooListeners are registered using the addFooListener method.

You can specify the listenerType argument with a class literal, such as FooListener.class. For example, you can query a document d for its document listeners with the following code:

DocumentListener[] mls = (DocumentListener[])(d.getListeners(DocumentListener.class));

If no such listeners exist, this method returns an empty array.

listener-type - the type of listeners requested; this parameter should specify an interface that descends from java.util.EventListener - java.lang.Class

returns: an array of all objects registered as FooListeners on this component, or an empty array if no such listeners have been added - <T extends java.util.EventListener> T[]

throws: java.lang.ClassCastException - if listenerType doesn't specify a class or interface that implements java.util.EventListener

get-paragraph-element clj

(get-paragraph-element this pos)

Get the paragraph element containing the given position. Sub-classes must define for themselves what exactly constitutes a paragraph. They should keep in mind however that a paragraph should at least be the unit of text over which to run the Unicode bidirectional algorithm.

pos - the starting offset >= 0 - int

returns: the element - javax.swing.text.Element

get-property clj

(get-property this key)

A convenience method for looking up a property value. It is equivalent to:

getDocumentProperties().get(key);

key - the non-null property key - java.lang.Object

returns: the value of this property or null - java.lang.Object

get-root-elements clj

(get-root-elements this)

Gets all root elements defined. Typically, there will only be one so the default implementation is to return the default root element.

returns: the root element - javax.swing.text.Element[]

get-start-position clj

(get-start-position this)

Returns a position that represents the start of the document. The position returned can be counted on to track change and stay located at the beginning of the document.

returns: the position - javax.swing.text.Position

get-text clj

(get-text this offset length)

(get-text this offset length txt)

Fetches the text contained within the given portion of the document.

If the partialReturn property on the txt parameter is false, the data returned in the Segment will be the entire length requested and may or may not be a copy depending upon how the data was stored. If the partialReturn property is true, only the amount of text that can be returned without creating a copy is returned. Using partial returns will give better performance for situations where large parts of the document are being scanned. The following is an example of using the partial return to access the entire document:

int nleft = doc.getDocumentLength(); Segment text = new Segment(); int offs = 0; text.setPartialReturn(true); while (nleft > 0) { doc.getText(offs, nleft, text); // do something with text nleft -= text.count; offs = text.count; }

offset - the starting offset >= 0 - int length - the number of characters to retrieve >= 0 - int txt - the Segment object to retrieve the text into - javax.swing.text.Segment

throws: javax.swing.text.BadLocationException - the range given includes a position that is not a valid position within the document

get-undoable-edit-listeners clj

(get-undoable-edit-listeners this)

Returns an array of all the undoable edit listeners registered on this document.

returns: all of this document's UndoableEditListeners or an empty array if no undoable edit listeners are currently registered - javax.swing.event.UndoableEditListener[]

insert-string clj

(insert-string this offs str a)

Inserts some content into the document. Inserting content causes a write lock to be held while the actual changes are taking place, followed by notification to the observers on the thread that grabbed the write lock.

This method is thread safe, although most Swing methods are not. Please see Concurrency in Swing for more information.

offs - the starting offset >= 0 - int str - the string to insert; does nothing with null/empty strings - java.lang.String a - the attributes for the inserted content - javax.swing.text.AttributeSet

throws: javax.swing.text.BadLocationException - the given insert position is not a valid position within the document

put-property clj

(put-property this key value)

A convenience method for storing up a property value. It is equivalent to:

getDocumentProperties().put(key, value); If value is null this method will remove the property.

key - the non-null key - java.lang.Object value - the property value - java.lang.Object

read-lock clj

(read-lock this)

Acquires a lock to begin reading some state from the document. There can be multiple readers at the same time. Writing blocks the readers until notification of the change to the listeners has been completed. This method should be used very carefully to avoid unintended compromise of the document. It should always be balanced with a readUnlock.

read-unlock clj

(read-unlock this)

Does a read unlock. This signals that one of the readers is done. If there are no more readers then writing can begin again. This should be balanced with a readLock, and should occur in a finally statement so that the balance is guaranteed. The following is an example.

readLock();
try {
    // do something
} finally {
    readUnlock();
}

remove clj

(remove this offs len)

Removes some content from the document. Removing content causes a write lock to be held while the actual changes are taking place. Observers are notified of the change on the thread that called this method.

This method is thread safe, although most Swing methods are not. Please see Concurrency in Swing for more information.

offs - the starting offset >= 0 - int len - the number of characters to remove >= 0 - int

throws: javax.swing.text.BadLocationException - the given remove position is not a valid position within the document

remove-document-listener clj

(remove-document-listener this listener)

Removes a document listener.

listener - the DocumentListener to remove - javax.swing.event.DocumentListener

remove-undoable-edit-listener clj

(remove-undoable-edit-listener this listener)

Removes an undo listener.

listener - the UndoableEditListener to remove - javax.swing.event.UndoableEditListener

render clj

(render this r)

This allows the model to be safely rendered in the presence of currency, if the model supports being updated asynchronously. The given runnable will be executed in a way that allows it to safely read the model with no changes while the runnable is being executed. The runnable itself may not make any mutations.

This is implemented to acquire a read lock for the duration of the runnables execution. There may be multiple runnables executing at the same time, and all writers will be blocked while there are active rendering runnables. If the runnable throws an exception, its lock will be safely released. There is no protection against a runnable that never exits, which will effectively leave the document locked for it's lifetime.

If the given runnable attempts to make any mutations in this implementation, a deadlock will occur. There is no tracking of individual rendering threads to enable detecting this situation, but a subclass could incur the overhead of tracking them and throwing an error.

This method is thread safe, although most Swing methods are not. Please see Concurrency in Swing for more information.

r - the renderer to execute - java.lang.Runnable

replace clj

(replace this offset length text attrs)

Deletes the region of text from offset to offset length, and replaces it with text. It is up to the implementation as to how this is implemented, some implementations may treat this as two distinct operations: a remove followed by an insert, others may treat the replace as one atomic operation.

offset - index of child element - int length - length of text to delete, may be 0 indicating don't delete anything - int text - text to insert, null indicates no text to insert - java.lang.String attrs - AttributeSet indicating attributes of inserted text, null is legal, and typically treated as an empty attributeset, but exact interpretation is left to the subclass - javax.swing.text.AttributeSet

throws: javax.swing.text.BadLocationException - the given position is not a valid position within the document

set-asynchronous-load-priority clj

(set-asynchronous-load-priority this p)

Sets the asynchronous loading priority.

p - the new asynchronous loading priority; a value less than zero indicates that the document should not be loaded asynchronously - int

set-document-filter clj

(set-document-filter this filter)

Sets the DocumentFilter. The DocumentFilter is passed insert and remove to conditionally allow inserting/deleting of the text. A null value indicates that no filtering will occur.

filter - the DocumentFilter used to constrain text - javax.swing.text.DocumentFilter

set-document-properties clj

(set-document-properties this x)

Replaces the document properties dictionary for this document.

x - the new dictionary - java.util.Dictionary