* 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 aquired 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 JavaBeansTM
* has been added to the
* You can specify the
* This is implemented to aquire 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.
*
* @param r the renderer to execute
*/
public void render(Runnable r) {
readLock();
try {
r.run();
} finally {
readUnlock();
}
}
/**
* Returns the length of the data. This is the number of
* characters of content that represents the users data.
*
* @return the length >= 0
* @see Document#getLength
*/
public int getLength() {
return data.length() - 1;
}
/**
* Adds a document listener for notification of any changes.
*
* @param listener the
* This method is thread safe, although most Swing methods
* are not. Please see
* Concurrency
* in Swing for more information.
*
* @param offs the starting offset >= 0
* @param len the number of characters to remove >= 0
* @exception BadLocationException the given remove position is not a valid
* position within the document
* @see Document#remove
*/
public void remove(int offs, int len) throws BadLocationException {
DocumentFilter filter = getDocumentFilter();
writeLock();
try {
if (filter != null) {
filter.remove(getFilterBypass(), offs, len);
}
else {
handleRemove(offs, len);
}
} finally {
writeUnlock();
}
}
/**
* Performs the actual work of the remove. It is assumed the caller
* will have obtained a
* This method is thread safe, although most Swing methods
* are not. Please see
* Concurrency
* in Swing for more information.
*
* @param offs the starting offset >= 0
* @param str the string to insert; does nothing with null/empty strings
* @param a the attributes for the inserted content
* @exception BadLocationException the given insert position is not a valid
* position within the document
* @see Document#insertString
*/
public void insertString(int offs, String str, AttributeSet a) throws BadLocationException {
if ((str == null) || (str.length() == 0)) {
return;
}
DocumentFilter filter = getDocumentFilter();
writeLock();
try {
if (filter != null) {
filter.insertString(getFilterBypass(), offs, str, a);
}
else {
handleInsertString(offs, str, a);
}
} finally {
writeUnlock();
}
}
/**
* Performs the actual work of inserting the text; it is assumed the
* caller has obtained a write lock before invoking this.
*/
void handleInsertString(int offs, String str, AttributeSet a)
throws BadLocationException {
if ((str == null) || (str.length() == 0)) {
return;
}
UndoableEdit u = data.insertString(offs, str);
DefaultDocumentEvent e =
new DefaultDocumentEvent(offs, str.length(), DocumentEvent.EventType.INSERT);
if (u != null) {
e.addEdit(u);
}
// see if complex glyph layout support is needed
if( getProperty(I18NProperty).equals( Boolean.FALSE ) ) {
// if a default direction of right-to-left has been specified,
// we want complex layout even if the text is all left to right.
Object d = getProperty(TextAttribute.RUN_DIRECTION);
if ((d != null) && (d.equals(TextAttribute.RUN_DIRECTION_RTL))) {
putProperty( I18NProperty, Boolean.TRUE);
} else {
char[] chars = str.toCharArray();
if (SwingUtilities2.isComplexLayout(chars, 0, chars.length)) {
putProperty( I18NProperty, Boolean.TRUE);
}
}
}
insertUpdate(e, a);
// Mark the edit as done.
e.end();
fireInsertUpdate(e);
// only fire undo if Content implementation supports it
// undo for the composed text is not supported for now
if (u != null &&
(a == null || !a.isDefined(StyleConstants.ComposedTextAttribute))) {
fireUndoableEditUpdate(new UndoableEditEvent(this, e));
}
}
/**
* Gets a sequence of text from the document.
*
* @param offset the starting offset >= 0
* @param length the number of characters to retrieve >= 0
* @return the text
* @exception BadLocationException the range given includes a position
* that is not a valid position within the document
* @see Document#getText
*/
public String getText(int offset, int length) throws BadLocationException {
if (length < 0) {
throw new BadLocationException("Length must be positive", length);
}
String str = data.getString(offset, length);
return str;
}
/**
* 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:
*
*
* This method is thread safe, although most Swing methods
* are not. Please see
* Concurrency
* in Swing for more information.
*
* @param offs the position in the model >= 0
* @return the position
* @exception BadLocationException if the given position does not
* represent a valid location in the associated document
* @see Document#createPosition
*/
public synchronized Position createPosition(int offs) throws BadLocationException {
return data.createPosition(offs);
}
/**
* 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.
*
* @return the position
*/
public final Position getStartPosition() {
Position p;
try {
p = createPosition(0);
} catch (BadLocationException bl) {
p = null;
}
return p;
}
/**
* 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.
*
* @return the position
*/
public final Position getEndPosition() {
Position p;
try {
p = createPosition(data.length());
} catch (BadLocationException bl) {
p = null;
}
return p;
}
/**
* Gets all root elements defined. Typically, there
* will only be one so the default implementation
* is to return the default root element.
*
* @return the root element
*/
public Element[] getRootElements() {
Element[] elems = new Element[2];
elems[0] = getDefaultRootElement();
elems[1] = getBidiRootElement();
return elems;
}
/**
* Returns the root element that views should be based upon
* unless some other mechanism for assigning views to element
* structures is provided.
*
* @return the root element
* @see Document#getDefaultRootElement
*/
public abstract Element getDefaultRootElement();
// ---- local methods -----------------------------------------
/**
* Returns the
* Calls to
* 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 JavaBeansTM
* has been added to the
* 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 JavaBeansTM
* has been added to the
* 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 JavaBeansTM
* has been added to the java.beans package.
* Please see {@link java.beans.XMLEncoder}.
*
* @author Timothy Prinzing
*/
public abstract class AbstractDocument implements Document, Serializable {
/**
* Constructs a new AbstractDocument, wrapped around some
* specified content storage mechanism.
*
* @param data the content
*/
protected AbstractDocument(Content data) {
this(data, StyleContext.getDefaultStyleContext());
}
/**
* Constructs a new AbstractDocument, wrapped around some
* specified content storage mechanism.
*
* @param data the content
* @param context the attribute context
*/
protected AbstractDocument(Content data, AttributeContext context) {
this.data = data;
this.context = context;
bidiRoot = new BidiRootElement();
if (defaultI18NProperty == null) {
// determine default setting for i18n support
String o = java.security.AccessController.doPrivileged(
new java.security.PrivilegedActiondocumentProperties dictionary
* to annotate the document with document-wide properties.
*
* @return a non-null Dictionary
* @see #setDocumentProperties
*/
public DictionaryFooListeners
* upon this document.
* FooListeners are registered using the
* addFooListener method.
*
* 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.
*
* @param listenerType the type of listeners requested; this parameter
* should specify an interface that descends from
* java.util.EventListener
* @return an array of all objects registered as
* FooListeners on this component,
* or an empty array if no such
* listeners have been added
* @exception ClassCastException if listenerType
* doesn't specify a class or interface that implements
* java.util.EventListener
*
* @see #getDocumentListeners
* @see #getUndoableEditListeners
*
* @since 1.3
*/
public -1
* if the document should not be loaded asynchronously
*/
public int getAsynchronousLoadPriority() {
Integer loadPriority = (Integer)
getProperty(AbstractDocument.AsyncLoadPriority);
if (loadPriority != null) {
return loadPriority.intValue();
}
return -1;
}
/**
* Sets the asynchronous loading priority.
* @param p the new asynchronous loading priority; a value
* less than zero indicates that the document should not be
* loaded asynchronously
*/
public void setAsynchronousLoadPriority(int p) {
Integer loadPriority = (p >= 0) ? Integer.valueOf(p) : null;
putProperty(AbstractDocument.AsyncLoadPriority, loadPriority);
}
/**
* 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.
*
* @param filter the DocumentFilter used to constrain text
* @see #getDocumentFilter
* @since 1.4
*/
public void setDocumentFilter(DocumentFilter filter) {
documentFilter = filter;
}
/**
* Returns the DocumentFilter that is responsible for
* filtering of insertion/removal. A null return value
* implies no filtering is to occur.
*
* @since 1.4
* @see #setDocumentFilter
* @return the DocumentFilter
*/
public DocumentFilter getDocumentFilter() {
return documentFilter;
}
// --- Document methods -----------------------------------------
/**
* 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.
* DocumentListener to add
* @see Document#addDocumentListener
*/
public void addDocumentListener(DocumentListener listener) {
listenerList.add(DocumentListener.class, listener);
}
/**
* Removes a document listener.
*
* @param listener the DocumentListener to remove
* @see Document#removeDocumentListener
*/
public void removeDocumentListener(DocumentListener listener) {
listenerList.remove(DocumentListener.class, listener);
}
/**
* Returns an array of all the document listeners
* registered on this document.
*
* @return all of this document's DocumentListeners
* or an empty array if no document listeners are
* currently registered
*
* @see #addDocumentListener
* @see #removeDocumentListener
* @since 1.4
*/
public DocumentListener[] getDocumentListeners() {
return listenerList.getListeners(DocumentListener.class);
}
/**
* 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.
*
* @param listener the UndoableEditListener to add
* @see Document#addUndoableEditListener
*/
public void addUndoableEditListener(UndoableEditListener listener) {
listenerList.add(UndoableEditListener.class, listener);
}
/**
* Removes an undo listener.
*
* @param listener the UndoableEditListener to remove
* @see Document#removeDocumentListener
*/
public void removeUndoableEditListener(UndoableEditListener listener) {
listenerList.remove(UndoableEditListener.class, listener);
}
/**
* Returns an array of all the undoable edit listeners
* registered on this document.
*
* @return all of this document's UndoableEditListeners
* or an empty array if no undoable edit listeners are
* currently registered
*
* @see #addUndoableEditListener
* @see #removeUndoableEditListener
*
* @since 1.4
*/
public UndoableEditListener[] getUndoableEditListeners() {
return listenerList.getListeners(UndoableEditListener.class);
}
/**
* A convenience method for looking up a property value. It is
* equivalent to:
*
* getDocumentProperties().get(key);
*
*
* @param key the non-null property key
* @return the value of this property or null
* @see #getDocumentProperties
*/
public final Object getProperty(Object key) {
return getDocumentProperties().get(key);
}
/**
* 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.
*
* @param key the non-null key
* @param value the property value
* @see #getDocumentProperties
*/
public final void putProperty(Object key, Object value) {
if (value != null) {
getDocumentProperties().put(key, value);
} else {
getDocumentProperties().remove(key);
}
if( key == TextAttribute.RUN_DIRECTION
&& Boolean.TRUE.equals(getProperty(I18NProperty)) )
{
//REMIND - this needs to flip on the i18n property if run dir
//is rtl and the i18n property is not already on.
writeLock();
try {
DefaultDocumentEvent e
= new DefaultDocumentEvent(0, getLength(),
DocumentEvent.EventType.INSERT);
updateBidi( e );
} finally {
writeUnlock();
}
}
}
/**
* 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.
* writeLock before invoking this.
*/
void handleRemove(int offs, int len) throws BadLocationException {
if (len > 0) {
if (offs < 0 || (offs + len) > getLength()) {
throw new BadLocationException("Invalid remove",
getLength() + 1);
}
DefaultDocumentEvent chng =
new DefaultDocumentEvent(offs, len, DocumentEvent.EventType.REMOVE);
boolean isComposedTextElement;
// Check whether the position of interest is the composed text
isComposedTextElement = Utilities.isComposedTextElement(this, offs);
removeUpdate(chng);
UndoableEdit u = data.remove(offs, len);
if (u != null) {
chng.addEdit(u);
}
postRemoveUpdate(chng);
// Mark the edit as done.
chng.end();
fireRemoveUpdate(chng);
// only fire undo if Content implementation supports it
// undo for the composed text is not supported for now
if ((u != null) && !isComposedTextElement) {
fireUndoableEditUpdate(new UndoableEditEvent(this, chng));
}
}
}
/**
* 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.
*
* @param offset index of child element
* @param length length of text to delete, may be 0 indicating don't
* delete anything
* @param text text to insert, null indicates no text to insert
* @param 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
* @exception BadLocationException the given position is not a valid
* position within the document
* @since 1.4
*/
public void replace(int offset, int length, String text,
AttributeSet attrs) throws BadLocationException {
if (length == 0 && (text == null || text.length() == 0)) {
return;
}
DocumentFilter filter = getDocumentFilter();
writeLock();
try {
if (filter != null) {
filter.replace(getFilterBypass(), offset, length, text,
attrs);
}
else {
if (length > 0) {
remove(offset, length);
}
if (text != null && text.length() > 0) {
insertString(offset, text, attrs);
}
}
} finally {
writeUnlock();
}
}
/**
* 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.
*
* 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;
* }
*
*
* @param offset the starting offset >= 0
* @param length the number of characters to retrieve >= 0
* @param txt the Segment object to retrieve the text into
* @exception BadLocationException the range given includes a position
* that is not a valid position within the document
*/
public void getText(int offset, int length, Segment txt) throws BadLocationException {
if (length < 0) {
throw new BadLocationException("Length must be positive", length);
}
data.getChars(offset, length, txt);
}
/**
* Returns a position that will track change as the document
* is altered.
* FilterBypass. This will create one if one
* does not yet exist.
*/
private DocumentFilter.FilterBypass getFilterBypass() {
if (filterBypass == null) {
filterBypass = new DefaultFilterBypass();
}
return filterBypass;
}
/**
* Returns the root element of the bidirectional structure for this
* document. Its children represent character runs with a given
* Unicode bidi level.
*/
public Element getBidiRootElement() {
return bidiRoot;
}
/**
* Returns true if the text in the range p0 to
* p1 is left to right.
*/
boolean isLeftToRight(int p0, int p1) {
if(!getProperty(I18NProperty).equals(Boolean.TRUE)) {
return true;
}
Element bidiRoot = getBidiRootElement();
int index = bidiRoot.getElementIndex(p0);
Element bidiElem = bidiRoot.getElement(index);
if(bidiElem.getEndOffset() >= p1) {
AttributeSet bidiAttrs = bidiElem.getAttributes();
return ((StyleConstants.getBidiLevel(bidiAttrs) % 2) == 0);
}
return true;
}
/**
* 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.
*
* @param pos the starting offset >= 0
* @return the element */
public abstract Element getParagraphElement(int pos);
/**
* Fetches the context for managing attributes. This
* method effectively establishes the strategy used
* for compressing AttributeSet information.
*
* @return the context
*/
protected final AttributeContext getAttributeContext() {
return context;
}
/**
* Updates document structure as a result of text insertion. This
* will happen within a write lock. If a subclass of
* this class reimplements this method, it should delegate to the
* superclass as well.
*
* @param chng a description of the change
* @param attr the attributes for the change
*/
protected void insertUpdate(DefaultDocumentEvent chng, AttributeSet attr) {
if( getProperty(I18NProperty).equals( Boolean.TRUE ) )
updateBidi( chng );
// Check if a multi byte is encountered in the inserted text.
if (chng.type == DocumentEvent.EventType.INSERT &&
chng.getLength() > 0 &&
!Boolean.TRUE.equals(getProperty(MultiByteProperty))) {
Segment segment = SegmentCache.getSharedSegment();
try {
getText(chng.getOffset(), chng.getLength(), segment);
segment.first();
do {
if ((int)segment.current() > 255) {
putProperty(MultiByteProperty, Boolean.TRUE);
break;
}
} while (segment.next() != Segment.DONE);
} catch (BadLocationException ble) {
// Should never happen
}
SegmentCache.releaseSharedSegment(segment);
}
}
/**
* Updates any document structure as a result of text removal. This
* method is called before the text is actually removed from the Content.
* This will happen within a write lock. If a subclass
* of this class reimplements this method, it should delegate to the
* superclass as well.
*
* @param chng a description of the change
*/
protected void removeUpdate(DefaultDocumentEvent chng) {
}
/**
* Updates any document structure as a result of text removal. This
* method is called after the text has been removed from the Content.
* This will happen within a write lock. If a subclass
* of this class reimplements this method, it should delegate to the
* superclass as well.
*
* @param chng a description of the change
*/
protected void postRemoveUpdate(DefaultDocumentEvent chng) {
if( getProperty(I18NProperty).equals( Boolean.TRUE ) )
updateBidi( chng );
}
/**
* Update the bidi element structure as a result of the given change
* to the document. The given change will be updated to reflect the
* changes made to the bidi structure.
*
* This method assumes that every offset in the model is contained in
* exactly one paragraph. This method also assumes that it is called
* after the change is made to the default element structure.
*/
void updateBidi( DefaultDocumentEvent chng ) {
// Calculate the range of paragraphs affected by the change.
int firstPStart;
int lastPEnd;
if( chng.type == DocumentEvent.EventType.INSERT
|| chng.type == DocumentEvent.EventType.CHANGE )
{
int chngStart = chng.getOffset();
int chngEnd = chngStart + chng.getLength();
firstPStart = getParagraphElement(chngStart).getStartOffset();
lastPEnd = getParagraphElement(chngEnd).getEndOffset();
} else if( chng.type == DocumentEvent.EventType.REMOVE ) {
Element paragraph = getParagraphElement( chng.getOffset() );
firstPStart = paragraph.getStartOffset();
lastPEnd = paragraph.getEndOffset();
} else {
throw new Error("Internal error: unknown event type.");
}
//System.out.println("updateBidi: firstPStart = " + firstPStart + " lastPEnd = " + lastPEnd );
// Calculate the bidi levels for the affected range of paragraphs. The
// levels array will contain a bidi level for each character in the
// affected text.
byte levels[] = calculateBidiLevels( firstPStart, lastPEnd );
Vectornull if there are no modifications in progress
*/
protected synchronized final Thread getCurrentWriter() {
return currWriter;
}
/**
* Acquires a lock to begin mutating the document this lock
* protects. There can be no writing, notification of changes, or
* reading going on in order to gain the lock. Additionally a thread is
* allowed to gain more than one writeLock,
* as long as it doesn't attempt to gain additional writeLocks
* from within document notification. Attempting to gain a
* writeLock from within a DocumentListener notification will
* result in an IllegalStateException. The ability
* to obtain more than one writeLock per thread allows
* subclasses to gain a writeLock, perform a number of operations, then
* release the lock.
* writeLock
* must be balanced with calls to writeUnlock, else the
* Document will be left in a locked state so that no
* reading or writing can be done.
*
* @exception IllegalStateException thrown on illegal lock
* attempt. If the document is implemented properly, this can
* only happen if a document listener attempts to mutate the
* document. This situation violates the bean event model
* where order of delivery is not guaranteed and all listeners
* should be notified before further mutations are allowed.
*/
protected synchronized final void writeLock() {
try {
while ((numReaders > 0) || (currWriter != null)) {
if (Thread.currentThread() == currWriter) {
if (notifyingListeners) {
// Assuming one doesn't do something wrong in a
// subclass this should only happen if a
// DocumentListener tries to mutate the document.
throw new IllegalStateException(
"Attempt to mutate in notification");
}
numWriters++;
return;
}
wait();
}
currWriter = Thread.currentThread();
numWriters = 1;
} catch (InterruptedException e) {
throw new Error("Interrupted attempt to aquire write lock");
}
}
/**
* Releases a write lock previously obtained via writeLock.
* After decrementing the lock count if there are no oustanding locks
* this will allow a new writer, or readers.
*
* @see #writeLock
*/
protected synchronized final void writeUnlock() {
if (--numWriters <= 0) {
numWriters = 0;
currWriter = null;
notifyAll();
}
}
/**
* 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.
*
* @see #readUnlock
*/
public synchronized final void readLock() {
try {
while (currWriter != null) {
if (currWriter == Thread.currentThread()) {
// writer has full read access.... may try to acquire
// lock in notification
return;
}
wait();
}
numReaders += 1;
} catch (InterruptedException e) {
throw new Error("Interrupted attempt to aquire read lock");
}
}
/**
* 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.
*
*
* @see #readLock
*/
public synchronized final void readUnlock() {
if (currWriter == Thread.currentThread()) {
// writer has full read access.... may try to acquire
// lock in notification
return;
}
if (numReaders <= 0) {
throw new StateInvariantError(BAD_LOCK_STATE);
}
numReaders -= 1;
notify();
}
// --- serialization ---------------------------------------------
private void readObject(ObjectInputStream s)
throws ClassNotFoundException, IOException
{
s.defaultReadObject();
listenerList = new EventListenerList();
// Restore bidi structure
//REMIND(bcb) This creates an initial bidi element to account for
//the \n that exists by default in the content.
bidiRoot = new BidiRootElement();
try {
writeLock();
Element[] p = new Element[1];
p[0] = new BidiElement( bidiRoot, 0, 1, 0 );
bidiRoot.replace(0,0,p);
} finally {
writeUnlock();
}
// At this point bidi root is only partially correct. To fully
// restore it we need access to getDefaultRootElement. But, this
// is created by the subclass and at this point will be null. We
// thus use registerValidation.
s.registerValidation(new ObjectInputValidation() {
public void validateObject() {
try {
writeLock();
DefaultDocumentEvent e = new DefaultDocumentEvent
(0, getLength(),
DocumentEvent.EventType.INSERT);
updateBidi( e );
}
finally {
writeUnlock();
}
}
}, 0);
}
// ----- member variables ------------------------------------------
private transient int numReaders;
private transient Thread currWriter;
/**
* The number of writers, all obtained from
* readLock();
* try {
* // do something
* } finally {
* readUnlock();
* }
* currWriter.
*/
private transient int numWriters;
/**
* True will notifying listeners.
*/
private transient boolean notifyingListeners;
private static Boolean defaultI18NProperty;
/**
* Storage for document-wide properties.
*/
private DictionaryEdit implementation will be returned,
* otherwise returns null
* @exception BadLocationException thrown if the area covered by
* the arguments is not contained in the character sequence
*/
public UndoableEdit insertString(int where, String str) throws BadLocationException;
/**
* Removes some portion of the sequence.
*
* @param where The offset into the sequence to make the
* insertion >= 0.
* @param nitems The number of items in the sequence to remove >= 0.
* @return If the implementation supports a history mechansim,
* a reference to an Edit implementation will be returned,
* otherwise null.
* @exception BadLocationException Thrown if the area covered by
* the arguments is not contained in the character sequence.
*/
public UndoableEdit remove(int where, int nitems) throws BadLocationException;
/**
* Fetches a string of characters contained in the sequence.
*
* @param where Offset into the sequence to fetch >= 0.
* @param len number of characters to copy >= 0.
* @return the string
* @exception BadLocationException Thrown if the area covered by
* the arguments is not contained in the character sequence.
*/
public String getString(int where, int len) throws BadLocationException;
/**
* Gets a sequence of characters and copies them into a Segment.
*
* @param where the starting offset >= 0
* @param len the number of characters >= 0
* @param txt the target location to copy into
* @exception BadLocationException Thrown if the area covered by
* the arguments is not contained in the character sequence.
*/
public void getChars(int where, int len, Segment txt) throws BadLocationException;
}
/**
* An interface that can be used to allow MutableAttributeSet
* implementations to use pluggable attribute compression
* techniques. Each mutation of the attribute set can be
* used to exchange a previous AttributeSet instance with
* another, preserving the possibility of the AttributeSet
* remaining immutable. An implementation is provided by
* the StyleContext class.
*
* The Element implementations provided by this class use
* this interface to provide their MutableAttributeSet
* implementations, so that different AttributeSet compression
* techniques can be employed. The method
* getAttributeContext should be implemented to
* return the object responsible for implementing the desired
* compression technique.
*
* @see StyleContext
*/
public interface AttributeContext {
/**
* Adds an attribute to the given set, and returns
* the new representative set.
*
* @param old the old attribute set
* @param name the non-null attribute name
* @param value the attribute value
* @return the updated attribute set
* @see MutableAttributeSet#addAttribute
*/
public AttributeSet addAttribute(AttributeSet old, Object name, Object value);
/**
* Adds a set of attributes to the element.
*
* @param old the old attribute set
* @param attr the attributes to add
* @return the updated attribute set
* @see MutableAttributeSet#addAttribute
*/
public AttributeSet addAttributes(AttributeSet old, AttributeSet attr);
/**
* Removes an attribute from the set.
*
* @param old the old attribute set
* @param name the non-null attribute name
* @return the updated attribute set
* @see MutableAttributeSet#removeAttribute
*/
public AttributeSet removeAttribute(AttributeSet old, Object name);
/**
* Removes a set of attributes for the element.
*
* @param old the old attribute set
* @param names the attribute names
* @return the updated attribute set
* @see MutableAttributeSet#removeAttributes
*/
public AttributeSet removeAttributes(AttributeSet old, Enumeration names);
/**
* Removes a set of attributes for the element.
*
* @param old the old attribute set
* @param attrs the attributes
* @return the updated attribute set
* @see MutableAttributeSet#removeAttributes
*/
public AttributeSet removeAttributes(AttributeSet old, AttributeSet attrs);
/**
* Fetches an empty AttributeSet.
*
* @return the attribute set
*/
public AttributeSet getEmptySet();
/**
* Reclaims an attribute set.
* This is a way for a MutableAttributeSet to mark that it no
* longer need a particular immutable set. This is only necessary
* in 1.1 where there are no weak references. A 1.1 implementation
* would call this in its finalize method.
*
* @param a the attribute set to reclaim
*/
public void reclaim(AttributeSet a);
}
/**
* Implements the abstract part of an element. By default elements
* support attributes by having a field that represents the immutable
* part of the current attribute set for the element. The element itself
* implements MutableAttributeSet which can be used to modify the set
* by fetching a new immutable set. The immutable sets are provided
* by the AttributeContext associated with the document.
* java.beans package.
* Please see {@link java.beans.XMLEncoder}.
*/
public abstract class AbstractElement implements Element, MutableAttributeSet, Serializable, TreeNode {
/**
* Creates a new AbstractElement.
*
* @param parent the parent element
* @param a the attributes for the element
* @since 1.4
*/
public AbstractElement(Element parent, AttributeSet a) {
this.parent = parent;
attributes = getAttributeContext().getEmptySet();
if (a != null) {
addAttributes(a);
}
}
private final void indent(PrintWriter out, int n) {
for (int i = 0; i < n; i++) {
out.print(" ");
}
}
/**
* Dumps a debugging representation of the element hierarchy.
*
* @param psOut the output stream
* @param indentAmount the indentation level >= 0
*/
public void dump(PrintStream psOut, int indentAmount) {
PrintWriter out;
try {
out = new PrintWriter(new OutputStreamWriter(psOut,"JavaEsc"),
true);
} catch (UnsupportedEncodingException e){
out = new PrintWriter(psOut,true);
}
indent(out, indentAmount);
if (getName() == null) {
out.print(" 0) {
out.println("");
// dump the attributes
Enumeration names = attributes.getAttributeNames();
while (names.hasMoreElements()) {
Object name = names.nextElement();
indent(out, indentAmount + 1);
out.println(name + "=" + getAttribute(name));
}
indent(out, indentAmount);
}
out.println(">");
if (isLeaf()) {
indent(out, indentAmount+1);
out.print("[" + getStartOffset() + "," + getEndOffset() + "]");
Content c = getContent();
try {
String contentStr = c.getString(getStartOffset(),
getEndOffset() - getStartOffset())/*.trim()*/;
if (contentStr.length() > 40) {
contentStr = contentStr.substring(0, 40) + "...";
}
out.println("["+contentStr+"]");
} catch (BadLocationException e) {
}
} else {
int n = getElementCount();
for (int i = 0; i < n; i++) {
AbstractElement e = (AbstractElement) getElement(i);
e.dump(psOut, indentAmount+1);
}
}
}
// --- AttributeSet ----------------------------
// delegated to the immutable field "attributes"
/**
* Gets the number of attributes that are defined.
*
* @return the number of attributes >= 0
* @see AttributeSet#getAttributeCount
*/
public int getAttributeCount() {
return attributes.getAttributeCount();
}
/**
* Checks whether a given attribute is defined.
*
* @param attrName the non-null attribute name
* @return true if the attribute is defined
* @see AttributeSet#isDefined
*/
public boolean isDefined(Object attrName) {
return attributes.isDefined(attrName);
}
/**
* Checks whether two attribute sets are equal.
*
* @param attr the attribute set to check against
* @return true if the same
* @see AttributeSet#isEqual
*/
public boolean isEqual(AttributeSet attr) {
return attributes.isEqual(attr);
}
/**
* Copies a set of attributes.
*
* @return the copy
* @see AttributeSet#copyAttributes
*/
public AttributeSet copyAttributes() {
return attributes.copyAttributes();
}
/**
* Gets the value of an attribute.
*
* @param attrName the non-null attribute name
* @return the attribute value
* @see AttributeSet#getAttribute
*/
public Object getAttribute(Object attrName) {
Object value = attributes.getAttribute(attrName);
if (value == null) {
// The delegate nor it's resolvers had a match,
// so we'll try to resolve through the parent
// element.
AttributeSet a = (parent != null) ? parent.getAttributes() : null;
if (a != null) {
value = a.getAttribute(attrName);
}
}
return value;
}
/**
* Gets the names of all attributes.
*
* @return the attribute names as an enumeration
* @see AttributeSet#getAttributeNames
*/
public Enumeration getAttributeNames() {
return attributes.getAttributeNames();
}
/**
* Checks whether a given attribute name/value is defined.
*
* @param name the non-null attribute name
* @param value the attribute value
* @return true if the name/value is defined
* @see AttributeSet#containsAttribute
*/
public boolean containsAttribute(Object name, Object value) {
return attributes.containsAttribute(name, value);
}
/**
* Checks whether the element contains all the attributes.
*
* @param attrs the attributes to check
* @return true if the element contains all the attributes
* @see AttributeSet#containsAttributes
*/
public boolean containsAttributes(AttributeSet attrs) {
return attributes.containsAttributes(attrs);
}
/**
* Gets the resolving parent.
* If not overridden, the resolving parent defaults to
* the parent element.
*
* @return the attributes from the parent, null if none
* @see AttributeSet#getResolveParent
*/
public AttributeSet getResolveParent() {
AttributeSet a = attributes.getResolveParent();
if ((a == null) && (parent != null)) {
a = parent.getAttributes();
}
return a;
}
// --- MutableAttributeSet ----------------------------------
// should fetch a new immutable record for the field
// "attributes".
/**
* Adds an attribute to the element.
*
* @param name the non-null attribute name
* @param value the attribute value
* @see MutableAttributeSet#addAttribute
*/
public void addAttribute(Object name, Object value) {
checkForIllegalCast();
AttributeContext context = getAttributeContext();
attributes = context.addAttribute(attributes, name, value);
}
/**
* Adds a set of attributes to the element.
*
* @param attr the attributes to add
* @see MutableAttributeSet#addAttribute
*/
public void addAttributes(AttributeSet attr) {
checkForIllegalCast();
AttributeContext context = getAttributeContext();
attributes = context.addAttributes(attributes, attr);
}
/**
* Removes an attribute from the set.
*
* @param name the non-null attribute name
* @see MutableAttributeSet#removeAttribute
*/
public void removeAttribute(Object name) {
checkForIllegalCast();
AttributeContext context = getAttributeContext();
attributes = context.removeAttribute(attributes, name);
}
/**
* Removes a set of attributes for the element.
*
* @param names the attribute names
* @see MutableAttributeSet#removeAttributes
*/
public void removeAttributes(Enumeration names) {
checkForIllegalCast();
AttributeContext context = getAttributeContext();
attributes = context.removeAttributes(attributes, names);
}
/**
* Removes a set of attributes for the element.
*
* @param attrs the attributes
* @see MutableAttributeSet#removeAttributes
*/
public void removeAttributes(AttributeSet attrs) {
checkForIllegalCast();
AttributeContext context = getAttributeContext();
if (attrs == this) {
attributes = context.getEmptySet();
} else {
attributes = context.removeAttributes(attributes, attrs);
}
}
/**
* Sets the resolving parent.
*
* @param parent the parent, null if none
* @see MutableAttributeSet#setResolveParent
*/
public void setResolveParent(AttributeSet parent) {
checkForIllegalCast();
AttributeContext context = getAttributeContext();
if (parent != null) {
attributes =
context.addAttribute(attributes, StyleConstants.ResolveAttribute,
parent);
} else {
attributes =
context.removeAttribute(attributes, StyleConstants.ResolveAttribute);
}
}
private final void checkForIllegalCast() {
Thread t = getCurrentWriter();
if ((t == null) || (t != Thread.currentThread())) {
throw new StateInvariantError("Illegal cast to MutableAttributeSet");
}
}
// --- Element methods -------------------------------------
/**
* Retrieves the underlying model.
*
* @return the model
*/
public Document getDocument() {
return AbstractDocument.this;
}
/**
* Gets the parent of the element.
*
* @return the parent
*/
public Element getParentElement() {
return parent;
}
/**
* Gets the attributes for the element.
*
* @return the attribute set
*/
public AttributeSet getAttributes() {
return this;
}
/**
* Gets the name of the element.
*
* @return the name, null if none
*/
public String getName() {
if (attributes.isDefined(ElementNameAttribute)) {
return (String) attributes.getAttribute(ElementNameAttribute);
}
return null;
}
/**
* Gets the starting offset in the model for the element.
*
* @return the offset >= 0
*/
public abstract int getStartOffset();
/**
* Gets the ending offset in the model for the element.
*
* @return the offset >= 0
*/
public abstract int getEndOffset();
/**
* Gets a child element.
*
* @param index the child index, >= 0 && < getElementCount()
* @return the child element
*/
public abstract Element getElement(int index);
/**
* Gets the number of children for the element.
*
* @return the number of children >= 0
*/
public abstract int getElementCount();
/**
* Gets the child element index closest to the given model offset.
*
* @param offset the offset >= 0
* @return the element index >= 0
*/
public abstract int getElementIndex(int offset);
/**
* Checks whether the element is a leaf.
*
* @return true if a leaf
*/
public abstract boolean isLeaf();
// --- TreeNode methods -------------------------------------
/**
* Returns the child TreeNode at index
* childIndex.
*/
public TreeNode getChildAt(int childIndex) {
return (TreeNode)getElement(childIndex);
}
/**
* Returns the number of children TreeNode's
* receiver contains.
* @return the number of children TreeNodews's
* receiver contains
*/
public int getChildCount() {
return getElementCount();
}
/**
* Returns the parent TreeNode of the receiver.
* @return the parent TreeNode of the receiver
*/
public TreeNode getParent() {
return (TreeNode)getParentElement();
}
/**
* Returns the index of node in the receivers children.
* If the receiver does not contain node, -1 will be
* returned.
* @param node the location of interest
* @return the index of node in the receiver's
* children, or -1 if absent
*/
public int getIndex(TreeNode node) {
for(int counter = getChildCount() - 1; counter >= 0; counter--)
if(getChildAt(counter) == node)
return counter;
return -1;
}
/**
* Returns true if the receiver allows children.
* @return true if the receiver allows children, otherwise false
*/
public abstract boolean getAllowsChildren();
/**
* Returns the children of the receiver as an
* Enumeration.
* @return the children of the receiver as an Enumeration
*/
public abstract Enumeration children();
// --- serialization ---------------------------------------------
private void writeObject(ObjectOutputStream s) throws IOException {
s.defaultWriteObject();
StyleContext.writeAttributeSet(s, attributes);
}
private void readObject(ObjectInputStream s)
throws ClassNotFoundException, IOException
{
s.defaultReadObject();
MutableAttributeSet attr = new SimpleAttributeSet();
StyleContext.readAttributeSet(s, attr);
AttributeContext context = getAttributeContext();
attributes = context.addAttributes(SimpleAttributeSet.EMPTY, attr);
}
// ---- variables -----------------------------------------------------
private Element parent;
private transient AttributeSet attributes;
}
/**
* Implements a composite element that contains other elements.
* java.beans package.
* Please see {@link java.beans.XMLEncoder}.
*/
public class BranchElement extends AbstractElement {
/**
* Constructs a composite element that initially contains
* no children.
*
* @param parent The parent element
* @param a the attributes for the element
* @since 1.4
*/
public BranchElement(Element parent, AttributeSet a) {
super(parent, a);
children = new AbstractElement[1];
nchildren = 0;
lastIndex = -1;
}
/**
* Gets the child element that contains
* the given model position.
*
* @param pos the position >= 0
* @return the element, null if none
*/
public Element positionToElement(int pos) {
int index = getElementIndex(pos);
Element child = children[index];
int p0 = child.getStartOffset();
int p1 = child.getEndOffset();
if ((pos >= p0) && (pos < p1)) {
return child;
}
return null;
}
/**
* Replaces content with a new set of elements.
*
* @param offset the starting offset >= 0
* @param length the length to replace >= 0
* @param elems the new elements
*/
public void replace(int offset, int length, Element[] elems) {
int delta = elems.length - length;
int src = offset + length;
int nmove = nchildren - src;
int dest = src + delta;
if ((nchildren + delta) >= children.length) {
// need to grow the array
int newLength = Math.max(2*children.length, nchildren + delta);
AbstractElement[] newChildren = new AbstractElement[newLength];
System.arraycopy(children, 0, newChildren, 0, offset);
System.arraycopy(elems, 0, newChildren, offset, elems.length);
System.arraycopy(children, src, newChildren, dest, nmove);
children = newChildren;
} else {
// patch the existing array
System.arraycopy(children, src, children, dest, nmove);
System.arraycopy(elems, 0, children, offset, elems.length);
}
nchildren = nchildren + delta;
}
/**
* Converts the element to a string.
*
* @return the string
*/
public String toString() {
return "BranchElement(" + getName() + ") " + getStartOffset() + "," +
getEndOffset() + "\n";
}
// --- Element methods -----------------------------------
/**
* Gets the element name.
*
* @return the element name
*/
public String getName() {
String nm = super.getName();
if (nm == null) {
nm = ParagraphElementName;
}
return nm;
}
/**
* Gets the starting offset in the model for the element.
*
* @return the offset >= 0
*/
public int getStartOffset() {
return children[0].getStartOffset();
}
/**
* Gets the ending offset in the model for the element.
* @throws NullPointerException if this element has no children
*
* @return the offset >= 0
*/
public int getEndOffset() {
Element child =
(nchildren > 0) ? children[nchildren - 1] : children[0];
return child.getEndOffset();
}
/**
* Gets a child element.
*
* @param index the child index, >= 0 && < getElementCount()
* @return the child element, null if none
*/
public Element getElement(int index) {
if (index < nchildren) {
return children[index];
}
return null;
}
/**
* Gets the number of children for the element.
*
* @return the number of children >= 0
*/
public int getElementCount() {
return nchildren;
}
/**
* Gets the child element index closest to the given model offset.
*
* @param offset the offset >= 0
* @return the element index >= 0
*/
public int getElementIndex(int offset) {
int index;
int lower = 0;
int upper = nchildren - 1;
int mid = 0;
int p0 = getStartOffset();
int p1;
if (nchildren == 0) {
return 0;
}
if (offset >= getEndOffset()) {
return nchildren - 1;
}
// see if the last index can be used.
if ((lastIndex >= lower) && (lastIndex <= upper)) {
Element lastHit = children[lastIndex];
p0 = lastHit.getStartOffset();
p1 = lastHit.getEndOffset();
if ((offset >= p0) && (offset < p1)) {
return lastIndex;
}
// last index wasn't a hit, but it does give useful info about
// where a hit (if any) would be.
if (offset < p0) {
upper = lastIndex;
} else {
lower = lastIndex;
}
}
while (lower <= upper) {
mid = lower + ((upper - lower) / 2);
Element elem = children[mid];
p0 = elem.getStartOffset();
p1 = elem.getEndOffset();
if ((offset >= p0) && (offset < p1)) {
// found the location
index = mid;
lastIndex = index;
return index;
} else if (offset < p0) {
upper = mid - 1;
} else {
lower = mid + 1;
}
}
// didn't find it, but we indicate the index of where it would belong
if (offset < p0) {
index = mid;
} else {
index = mid + 1;
}
lastIndex = index;
return index;
}
/**
* Checks whether the element is a leaf.
*
* @return true if a leaf
*/
public boolean isLeaf() {
return false;
}
// ------ TreeNode ----------------------------------------------
/**
* Returns true if the receiver allows children.
* @return true if the receiver allows children, otherwise false
*/
public boolean getAllowsChildren() {
return true;
}
/**
* Returns the children of the receiver as an
* Enumeration.
* @return the children of the receiver
*/
public Enumeration children() {
if(nchildren == 0)
return null;
Vectorjava.beans package.
* Please see {@link java.beans.XMLEncoder}.
*
* @see Element
*/
public class LeafElement extends AbstractElement {
/**
* Constructs an element that represents content within the
* document (has no children).
*
* @param parent The parent element
* @param a The element attributes
* @param offs0 The start offset >= 0
* @param offs1 The end offset >= offs0
* @since 1.4
*/
public LeafElement(Element parent, AttributeSet a, int offs0, int offs1) {
super(parent, a);
try {
p0 = createPosition(offs0);
p1 = createPosition(offs1);
} catch (BadLocationException e) {
p0 = null;
p1 = null;
throw new StateInvariantError("Can't create Position references");
}
}
/**
* Converts the element to a string.
*
* @return the string
*/
public String toString() {
return "LeafElement(" + getName() + ") " + p0 + "," + p1 + "\n";
}
// --- Element methods ---------------------------------------------
/**
* Gets the starting offset in the model for the element.
*
* @return the offset >= 0
*/
public int getStartOffset() {
return p0.getOffset();
}
/**
* Gets the ending offset in the model for the element.
*
* @return the offset >= 0
*/
public int getEndOffset() {
return p1.getOffset();
}
/**
* Gets the element name.
*
* @return the name
*/
public String getName() {
String nm = super.getName();
if (nm == null) {
nm = ContentElementName;
}
return nm;
}
/**
* Gets the child element index closest to the given model offset.
*
* @param pos the offset >= 0
* @return the element index >= 0
*/
public int getElementIndex(int pos) {
return -1;
}
/**
* Gets a child element.
*
* @param index the child index, >= 0 && < getElementCount()
* @return the child element
*/
public Element getElement(int index) {
return null;
}
/**
* Returns the number of child elements.
*
* @return the number of children >= 0
*/
public int getElementCount() {
return 0;
}
/**
* Checks whether the element is a leaf.
*
* @return true if a leaf
*/
public boolean isLeaf() {
return true;
}
// ------ TreeNode ----------------------------------------------
/**
* Returns true if the receiver allows children.
* @return true if the receiver allows children, otherwise false
*/
public boolean getAllowsChildren() {
return false;
}
/**
* Returns the children of the receiver as an
* Enumeration.
* @return the children of the receiver
*/
public Enumeration children() {
return null;
}
// --- serialization ---------------------------------------------
private void writeObject(ObjectOutputStream s) throws IOException {
s.defaultWriteObject();
s.writeInt(p0.getOffset());
s.writeInt(p1.getOffset());
}
private void readObject(ObjectInputStream s)
throws ClassNotFoundException, IOException
{
s.defaultReadObject();
// set the range with positions that track change
int off0 = s.readInt();
int off1 = s.readInt();
try {
p0 = createPosition(off0);
p1 = createPosition(off1);
} catch (BadLocationException e) {
p0 = null;
p1 = null;
throw new IOException("Can't restore Position references");
}
}
// ---- members -----------------------------------------------------
private transient Position p0;
private transient Position p1;
}
/**
* Represents the root element of the bidirectional element structure.
* The root element is the only element in the bidi element structure
* which contains children.
*/
class BidiRootElement extends BranchElement {
BidiRootElement() {
super( null, null );
}
/**
* Gets the name of the element.
* @return the name
*/
public String getName() {
return "bidi root";
}
}
/**
* Represents an element of the bidirectional element structure.
*/
class BidiElement extends LeafElement {
/**
* Creates a new BidiElement.
*/
BidiElement(Element parent, int start, int end, int level) {
super(parent, new SimpleAttributeSet(), start, end);
addAttribute(StyleConstants.BidiLevel, Integer.valueOf(level));
//System.out.println("BidiElement: start = " + start
// + " end = " + end + " level = " + level );
}
/**
* Gets the name of the element.
* @return the name
*/
public String getName() {
return BidiElementName;
}
int getLevel() {
Integer o = (Integer) getAttribute(StyleConstants.BidiLevel);
if (o != null) {
return o.intValue();
}
return 0; // Level 0 is base level (non-embedded) left-to-right
}
boolean isLeftToRight() {
return ((getLevel() % 2) == 0);
}
}
/**
* Stores document changes as the document is being
* modified. Can subsequently be used for change notification
* when done with the document modification transaction.
* This is used by the AbstractDocument class and its extensions
* for broadcasting change information to the document listeners.
*/
public class DefaultDocumentEvent extends CompoundEdit implements DocumentEvent {
/**
* Constructs a change record.
*
* @param offs the offset into the document of the change >= 0
* @param len the length of the change >= 0
* @param type the type of event (DocumentEvent.EventType)
* @since 1.4
*/
public DefaultDocumentEvent(int offs, int len, DocumentEvent.EventType type) {
super();
offset = offs;
length = len;
this.type = type;
}
/**
* Returns a string description of the change event.
*
* @return a string
*/
public String toString() {
return edits.toString();
}
// --- CompoundEdit methods --------------------------
/**
* Adds a document edit. If the number of edits crosses
* a threshold, this switches on a hashtable lookup for
* ElementChange implementations since access of these
* needs to be relatively quick.
*
* @param anEdit a document edit record
* @return true if the edit was added
*/
public boolean addEdit(UndoableEdit anEdit) {
// if the number of changes gets too great, start using
// a hashtable for to locate the change for a given element.
if ((changeLookup == null) && (edits.size() > 10)) {
changeLookup = new Hashtable