Java example source code file (AbstractDocument.java)
The AbstractDocument.java Java example source code/* * Copyright (c) 1997, 2013, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation. Oracle designates this * particular file as subject to the "Classpath" exception as provided * by Oracle in the LICENSE file that accompanied this code. * * This code is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. */ package javax.swing.text; import java.util.*; import java.io.*; import java.awt.font.TextAttribute; import java.text.Bidi; import javax.swing.UIManager; import javax.swing.undo.*; import javax.swing.event.*; import javax.swing.tree.TreeNode; import sun.font.BidiUtils; import sun.swing.SwingUtilities2; /** * 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. * <p> * 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 <code>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. * <p> * 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 * <code>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. * <p> * 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 <code>repaint and* * 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 * <code>java.util.EventListener * @return an array of all objects registered as * <code>FooListeners on this component, * or an empty array if no such * listeners have been added * @exception ClassCastException if <code>listenerType * doesn't specify a class or interface that implements * <code>java.util.EventListener * * @see #getDocumentListeners * @see #getUndoableEditListeners * * @since 1.3 */ public <T extends EventListener> T[] getListeners(Class DocumentFilter
* is passed <code>insert and remove to conditionally
* allow inserting/deleting of the text. A <code>null value
* indicates that no filtering will occur.
*
* @param filter the <code>DocumentFilter used to constrain text
* @see #getDocumentFilter
* @since 1.4
*/
public void setDocumentFilter(DocumentFilter filter) {
documentFilter = filter;
}
/**
* Returns the <code>DocumentFilter that is responsible for
* filtering of insertion/removal. A <code>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 <em>not
* make any mutations.
* <p>
* 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.
* <p>
* 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.
* <p>
* This method is thread safe, although most Swing methods
* are not. Please see
* <A HREF="http://docs.oracle.com/javase/tutorial/uiswing/concurrency/index.html">Concurrency
* in Swing</A> 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 <code>DocumentListener to add
* @see Document#addDocumentListener
*/
public void addDocumentListener(DocumentListener listener) {
listenerList.add(DocumentListener.class, listener);
}
/**
* Removes a document listener.
*
* @param listener the <code>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 <code>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 <code>UndoableEdit
* will cause the appropriate DocumentEvent to be fired to keep
* the view(s) in sync with the model.
*
* @param listener the <code>UndoableEditListener to add
* @see Document#addUndoableEditListener
*/
public void addUndoableEditListener(UndoableEditListener listener) {
listenerList.add(UndoableEditListener.class, listener);
}
/**
* Removes an undo listener.
*
* @param listener the <code>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 <code>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:
* <pre>
* getDocumentProperties().get(key);
* </pre>
*
* @param key the non-<code>null property key
* @return the value of this property or <code>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:
* <pre>
* getDocumentProperties().put(key, value);
* </pre>
* If <code>value is null this method will
* remove the property.
*
* @param key the non-<code>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.
* <p>
* This method is thread safe, although most Swing methods
* are not. Please see
* <A HREF="http://docs.oracle.com/javase/tutorial/uiswing/concurrency/index.html">Concurrency
* in Swing</A> 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 <code>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 <code>offset to
* <code>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, <code>null indicates no text to insert
* @param attrs AttributeSet indicating attributes of inserted text,
* <code>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.
* <p>
* This method is thread safe, although most Swing methods
* are not. Please see
* <A HREF="http://docs.oracle.com/javase/tutorial/uiswing/concurrency/index.html">Concurrency
* in Swing</A> 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.
*/
private 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.
* <p>
* 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:
*
* <pre>
* 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;
* }
* </pre>
*
* @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.
* <p>
* This method is thread safe, although most Swing methods
* are not. Please see
* <A HREF="http://docs.oracle.com/javase/tutorial/uiswing/concurrency/index.html">Concurrency
* in Swing</A> 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 <code>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 <code>p0 to
* <code>p1 is left to right.
*/
static boolean isLeftToRight(Document doc, int p0, int p1) {
if (Boolean.TRUE.equals(doc.getProperty(I18NProperty))) {
if (doc instanceof AbstractDocument) {
AbstractDocument adoc = (AbstractDocument) doc;
Element bidiRoot = adoc.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 );
Vector<Element> newElements = new Vector
* readLock();
* try {
* // do something
* } finally {
* readUnlock();
* }
* </code>
*
* @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 <code>currWriter.
*/
private transient int numWriters;
/**
* True will notifying listeners.
*/
private transient boolean notifyingListeners;
private static Boolean defaultI18NProperty;
/**
* Storage for document-wide properties.
*/
private Dictionary<Object,Object> documentProperties = null;
/**
* The event listener list for the document.
*/
protected EventListenerList listenerList = new EventListenerList();
/**
* Where the text is actually stored, and a set of marks
* that track change as the document is edited are managed.
*/
private Content data;
/**
* Factory for the attributes. This is the strategy for
* attribute compression and control of the lifetime of
* a set of attributes as a collection. This may be shared
* with other documents.
*/
private AttributeContext context;
/**
* The root of the bidirectional structure for this document. Its children
* represent character runs with the same Unicode bidi level.
*/
private transient BranchElement bidiRoot;
/**
* Filter for inserting/removing of text.
*/
private DocumentFilter documentFilter;
/**
* Used by DocumentFilter to do actual insert/remove.
*/
private transient DocumentFilter.FilterBypass filterBypass;
private static final String BAD_LOCK_STATE = "document lock failure";
/**
* Error message to indicate a bad location.
*/
protected static final String BAD_LOCATION = "document location failure";
/**
* Name of elements used to represent paragraphs
*/
public static final String ParagraphElementName = "paragraph";
/**
* Name of elements used to represent content
*/
public static final String ContentElementName = "content";
/**
* Name of elements used to hold sections (lines/paragraphs).
*/
public static final String SectionElementName = "section";
/**
* Name of elements used to hold a unidirectional run
*/
public static final String BidiElementName = "bidi level";
/**
* Name of the attribute used to specify element
* names.
*/
public static final String ElementNameAttribute = "$ename";
/**
* Document property that indicates whether internationalization
* functions such as text reordering or reshaping should be
* performed. This property should not be publicly exposed,
* since it is used for implementation convenience only. As a
* side effect, copies of this property may be in its subclasses
* that live in different packages (e.g. HTMLDocument as of now),
* so those copies should also be taken care of when this property
* needs to be modified.
*/
static final String I18NProperty = "i18n";
/**
* Document property that indicates if a character has been inserted
* into the document that is more than one byte long. GlyphView uses
* this to determine if it should use BreakIterator.
*/
static final Object MultiByteProperty = "multiByte";
/**
* Document property that indicates asynchronous loading is
* desired, with the thread priority given as the value.
*/
static final String AsyncLoadPriority = "load priority";
/**
* Interface to describe a sequence of character content that
* can be edited. Implementations may or may not support a
* history mechanism which will be reflected by whether or not
* mutations return an UndoableEdit implementation.
* @see AbstractDocument
*/
public interface Content {
/**
* Creates a position within the content that will
* track change as the content is mutated.
*
* @param offset the offset in the content >= 0
* @return a Position
* @exception BadLocationException for an invalid offset
*/
public Position createPosition(int offset) throws BadLocationException;
/**
* Current length of the sequence of character content.
*
* @return the length >= 0
*/
public int length();
/**
* Inserts a string of characters into the sequence.
*
* @param where offset into the sequence to make the insertion >= 0
* @param str string to insert
* @return if the implementation supports a history mechanism,
* a reference to an <code>Edit implementation will be returned,
* otherwise returns <code>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 mechanism,
* 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
* <code>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.
* <p>
* <strong>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 <code>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("<??");
} else {
out.print("<" + getName());
}
if (getAttributeCount() > 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, <code>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 <code>TreeNode at index
* <code>childIndex.
*/
public TreeNode getChildAt(int childIndex) {
return (TreeNode)getElement(childIndex);
}
/**
* Returns the number of children <code>TreeNode's
* receiver contains.
* @return the number of children <code>TreeNodews's
* receiver contains
*/
public int getChildCount() {
return getElementCount();
}
/**
* Returns the parent <code>TreeNode of the receiver.
* @return the parent <code>TreeNode of the receiver
*/
public TreeNode getParent() {
return (TreeNode)getParentElement();
}
/**
* Returns the index of <code>node in the receivers children.
* If the receiver does not contain <code>node, -1 will be
* returned.
* @param node the location of interest
* @return the index of <code>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
* <code>Enumeration.
* @return the children of the receiver as an <code>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.
* <p>
* <strong>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 <code>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
* <code>Enumeration.
* @return the children of the receiver
*/
public Enumeration children() {
if(nchildren == 0)
return null;
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