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The NetBeans Platform is a generic base for desktop applications. It provides the services common
to almost all large desktop applications: window management, menus, settings and storage, an update
manager, and file access. Get a head start by reusing these standard components, allowing you to
concentrate fully on your application's business logic.
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/*
* Sun Public License Notice
*
* The contents of this file are subject to the Sun Public License
* Version 1.0 (the "License"). You may not use this file except in
* compliance with the License. A copy of the License is available at
* http://www.sun.com/
*
* The Original Code is NetBeans. The Initial Developer of the Original
* Code is Sun Microsystems, Inc. Portions Copyright 1997-2004 Sun
* Microsystems, Inc. All Rights Reserved.
*/
package org.openide.loaders;
import java.awt.datatransfer.*;
import java.beans.*;
import java.io.*;
import java.lang.reflect.InvocationTargetException;
import java.util.*;
import javax.swing.Action;
import org.openide.ErrorManager;
import org.openide.filesystems.*;
import org.openide.filesystems.FileSystem.HtmlStatus;
import org.openide.util.datatransfer.*;
import org.openide.util.HelpCtx;
import org.openide.util.RequestProcessor;
import org.openide.util.NbBundle;
import org.openide.util.actions.SystemAction;
import org.openide.nodes.*;
import org.openide.util.Mutex;
/** Standard node representing a data object.
*
* @author Jaroslav Tulach
*/
public class DataNode extends AbstractNode {
/** generated Serialized Version UID */
static final long serialVersionUID = -7882925922830244768L;
/** DataObject of this node. */
private DataObject obj;
/** property change listener */
private PropL propL;
/** should file extensions be displayed? */
private static boolean showFileExtensions = true;
/** Create a data node for a given data object.
* The provided children object will be used to hold all child nodes.
* The name is always set to the base name of the primary file;
* the display name may instead be set to the base name with extension.
* @param obj object to work with
* @param ch children container for the node
* @see #getShowFileExtensions
*/
public DataNode (DataObject obj, Children ch) {
super (ch);
this.obj = obj;
propL = new PropL ();
obj.addPropertyChangeListener (org.openide.util.WeakListeners.propertyChange (propL, obj));
super.setName (obj.getName ());
updateDisplayName ();
}
private void updateDisplayName () {
FileObject prim = obj.getPrimaryFile ();
String newDisplayName;
if (prim.isRoot()) {
// Special case - getName{,Ext} will just return "".
// Used to be handled by org.netbeans.core.RootFolderNode
// but might as well do it here.
// XXX replace with #37549
File f = FileUtil.toFile(prim);
if (f == null) {
// Check for a JAR root explicitly.
FileObject archiveFile = FileUtil.getArchiveFile(prim);
if (archiveFile != null) {
f = FileUtil.toFile(archiveFile);
}
}
if (f != null) {
// E.g. /tmp/foo or /tmp/foo.jar
newDisplayName = f.getAbsolutePath();
} else {
try {
// E.g. http://webdavhost.nowhere.net/mystuff/
newDisplayName = prim.getURL().toExternalForm();
} catch (FileStateInvalidException e) {
// Should not happen in practice.
newDisplayName = "???"; // NOI18N
}
}
} else if (showFileExtensions || obj instanceof DataFolder || obj instanceof DefaultDataObject) {
newDisplayName = prim.getNameExt();
} else {
newDisplayName = prim.getName ();
}
if (displayFormat != null)
setDisplayName (displayFormat.format (new Object[] { newDisplayName }));
else
setDisplayName (newDisplayName);
}
/** Get the represented data object.
* @return the data object
*/
public DataObject getDataObject() {
return obj;
}
/** Changes the name of the node and may also rename the data object.
* If the object is renamed and file extensions are to be shown,
* the display name is also updated accordingly.
*
* @param name new name for the object
* @param rename rename the data object?
* @exception IllegalArgumentException if the rename failed
*/
public void setName (String name, boolean rename) {
try {
if (rename) {
obj.rename (name);
}
super.setName (name);
if (rename) updateDisplayName ();
} catch (IOException ex) {
String msg = null;
if ((ex.getLocalizedMessage() == null) ||
(ex.getLocalizedMessage().equals(ex.getMessage()))) {
msg = NbBundle.getMessage (DataNode.class, "MSG_renameError", getName (), name); // NOI18N
} else {
msg = ex.getLocalizedMessage();
}
RuntimeException e = new IllegalArgumentException();
ErrorManager.getDefault().copyAnnotation (e, ex);
ErrorManager.getDefault().annotate (e, ErrorManager.USER, null, msg, null, null);
throw e;
}
}
/* Rename the data object.
* @param name new name for the object
* @exception IllegalArgumentException if the rename failed
*/
public void setName (String name) {
setName (name, true);
}
/** Get the display name for the node.
* A filesystem may {@link org.openide.filesystems.FileSystem#getStatus specially alter} this.
* Subclassers overriding this method should consider the recommendations
* in {@link DataObject#createNodeDelegate}.
* @return the desired name
*/
public String getDisplayName () {
String s = super.getDisplayName ();
try {
s = obj.getPrimaryFile ().getFileSystem ().getStatus ().annotateName (s, new LazyFilesSet());
} catch (FileStateInvalidException e) {
// no fs, do nothing
}
return s;
}
/** Get a display name formatted using the limited HTML subset supported
* by HtmlRenderer. If the underlying
* FileSystem.Status is an instance of HmlStatus,
* this method will return non-null if status information is added.
*
* @return a string containing compliant HTML markup or null
* @see org.openide.awt.HtmlRenderer
* @see org.openide.nodes.Node#getHtmlDisplayName
* @since 4.13
*/
public String getHtmlDisplayName() {
try {
FileSystem.Status stat =
obj.getPrimaryFile().getFileSystem().getStatus();
if (stat instanceof HtmlStatus) {
HtmlStatus hstat = (HtmlStatus) stat;
String result = hstat.annotateNameHtml (
super.getDisplayName(), new LazyFilesSet());
//Make sure the super string was really modified
if (!super.getDisplayName().equals(result)) {
return result;
}
}
} catch (FileStateInvalidException e) {
//do nothing and fall through
}
return super.getHtmlDisplayName();
}
/** Get the displayed icon for this node.
* A filesystem may {@link org.openide.filesystems.FileSystem#getStatus specially alter} this.
* Subclassers overriding this method should consider the recommendations
* in {@link DataObject#createNodeDelegate}.
* @param type the icon type from {@link java.beans.BeanInfo}
* @return the desired icon
*/
public java.awt.Image getIcon (int type) {
java.awt.Image img = super.getIcon (type);
try {
img = obj.getPrimaryFile ().getFileSystem ().getStatus ().annotateIcon (img, type, new LazyFilesSet());
} catch (FileStateInvalidException e) {
// no fs, do nothing
}
return img;
}
/** Get the displayed icon for this node.
* A filesystem may {@link org.openide.filesystems.FileSystem#getStatus specially alter} this.
* Subclassers overriding this method should consider the recommendations
* in {@link DataObject#createNodeDelegate}.
* @param type the icon type from {@link java.beans.BeanInfo}
* @return the desired icon
*/
public java.awt.Image getOpenedIcon (int type) {
java.awt.Image img = super.getOpenedIcon(type);
try {
img = obj.getPrimaryFile ().getFileSystem ().getStatus ().annotateIcon (img, type, new LazyFilesSet());
} catch (FileStateInvalidException e) {
// no fs, do nothing
}
return img;
}
public HelpCtx getHelpCtx () {
return obj.getHelpCtx ();
}
/** Indicate whether the node may be renamed.
* @return tests {@link DataObject#isRenameAllowed}
*/
public boolean canRename () {
return obj.isRenameAllowed ();
}
/** Indicate whether the node may be destroyed.
* @return tests {@link DataObject#isDeleteAllowed}
*/
public boolean canDestroy () {
return obj.isDeleteAllowed ();
}
/* Destroyes the node
*/
public void destroy () throws IOException {
if (obj.isDeleteAllowed ()) {
obj.delete ();
}
super.destroy ();
}
/* Returns true if this object allows copying.
* @returns true if this object allows copying.
*/
public boolean canCopy () {
return obj.isCopyAllowed ();
}
/* Returns true if this object allows cutting.
* @returns true if this object allows cutting.
*/
public boolean canCut () {
return obj.isMoveAllowed ();
}
/** This method returns null to signal that actions
* provide by DataLoader.getActions should be returned from
* method getActions. If overriden to provide some actions,
* then these actions will be preferred to the loader's ones.
*
* @return null
*/
protected SystemAction[] createActions () {
return null;
}
/** Get actions for this data object.
* @see DataLoader#getActions
* @return array of actions or null
*/
public SystemAction[] getActions () {
if (systemActions == null) {
systemActions = createActions ();
}
if (systemActions != null) {
return systemActions;
}
return obj.getLoader ().getActions ();
}
/** Get default action. In the current implementation the
*null is returned in case the underlying data
* object is a template. The templates should not have any default
* action.
* @return no action if the underlying data object is a template.
* Otherwise the abstract node's default action is returned, if null then
* the first action returned from getActions (false) method is used.
*/
public Action getPreferredAction () {
if (obj.isTemplate ()) {
return null;
} else {
Action action = super.getPreferredAction ();
if (action != null) {
return action;
}
Action[] arr = getActions(false);
if (arr != null && arr.length > 0) {
return arr[0];
}
return null;
}
}
/** Get a cookie.
* First of all {@link DataObject#getCookie} is
* called. If it produces non-null result, that is returned.
* Otherwise the superclass is tried.
* Subclassers overriding this method should consider the recommendations
* in {@link DataObject#createNodeDelegate}.
*
* @return the cookie or null
*/
public Node.Cookie getCookie (Class cl) {
Node.Cookie c = obj.getCookie (cl);
if (c != null) {
return c;
} else {
return super.getCookie (cl);
}
}
/* Initializes sheet of properties. Allow subclasses to
* overwrite it.
* @return the default sheet to use
*/
protected Sheet createSheet () {
Sheet s = Sheet.createDefault ();
Sheet.Set ss = s.get (Sheet.PROPERTIES);
Node.Property p;
p = createNameProperty (obj);
ss.put (p);
FileObject fo = getDataObject().getPrimaryFile();
if (couldBeTemplate(fo) && !fo.isReadOnly()) {
try {
p = new PropertySupport.Reflection(obj, Boolean.TYPE, "isTemplate", "setTemplate"); // NOI18N
p.setName(DataObject.PROP_TEMPLATE);
p.setDisplayName(DataObject.getString("PROP_template"));
p.setShortDescription(DataObject.getString("HINT_template"));
ss.put(p);
} catch (Exception ex) {
throw new InternalError();
}
}
if (fo.isData()) {
ss.put(new AllFilesProperty());
ss.put(new SizeProperty());
ss.put(new LastModifiedProperty());
}
return s;
}
private static boolean couldBeTemplate(FileObject fo) {
FileSystem fs;
try {
fs = fo.getFileSystem();
} catch (FileStateInvalidException e) {
return false;
}
return fs.isDefault() && fo.getPath().startsWith("Templates/"); // NOI18N
}
/**
* A property with a list of all contained files.
* Sorted to first show primary file, then all secondary files alphabetically.
* Shows absolute file path or the closest equivalent.
*/
private final class AllFilesProperty extends PropertySupport.ReadOnly {
public AllFilesProperty() {
super(DataObject.PROP_FILES, String[].class,
DataObject.getString("PROP_files"), DataObject.getString("HINT_files"));
}
public Object getValue() {
Set files = obj.files();
String[] toret = new String[files.size()];
int i = 0; for (Iterator it = files.iterator(); it.hasNext(); i++) {
toret[i] = name((FileObject)it.next());
}
final String pfilename = name(obj.getPrimaryFile());
Arrays.sort(toret, new Comparator() {
public int compare(Object o1, Object o2) {
String fname1 = (String) o1;
String fname2 = (String) o2;
if (fname1.equals(pfilename))
return -1;
else if (fname2.equals(pfilename))
return 1;
else
return fname1.compareTo(fname2);
}
});
return toret;
}
private String name(FileObject fo) {
return FileUtil.getFileDisplayName(fo);
}
}
private final class SizeProperty extends PropertySupport.ReadOnly {
public SizeProperty() {
super("size", Long.TYPE, DataObject.getString("PROP_size"), DataObject.getString("HINT_size"));
}
public Object getValue() {
return new Long(getDataObject().getPrimaryFile().getSize());
}
}
private final class LastModifiedProperty extends PropertySupport.ReadOnly {
public LastModifiedProperty() {
super("lastModified", Date.class, DataObject.getString("PROP_lastModified"), DataObject.getString("HINT_lastModified"));
}
public Object getValue() {
return getDataObject().getPrimaryFile().lastModified();
}
}
/** Copy this node to the clipboard.
*
* @return {@link org.openide.util.datatransfer.ExTransferable.Single} with one copy flavor
* @throws IOException if it could not copy
* @see NodeTransfer
*/
public Transferable clipboardCopy () throws IOException {
ExTransferable t = ExTransferable.create (super.clipboardCopy ());
t.put (LoaderTransfer.transferable (
getDataObject (),
LoaderTransfer.CLIPBOARD_COPY)
);
return t;
}
/** Cut this node to the clipboard.
*
* @return {@link org.openide.util.datatransfer.ExTransferable.Single} with one cut flavor
* @throws IOException if it could not cut
* @see NodeTransfer
*/
public Transferable clipboardCut () throws IOException {
ExTransferable t = ExTransferable.create (super.clipboardCut ());
t.put (LoaderTransfer.transferable (
getDataObject (),
LoaderTransfer.CLIPBOARD_CUT)
);
return t;
}
/** Creates a name property for given data object.
*/
static Node.Property createNameProperty (final DataObject obj) {
Node.Property p = new PropertySupport.ReadWrite (
DataObject.PROP_NAME,
String.class,
DataObject.getString("PROP_name"),
DataObject.getString("HINT_name")
) {
public Object getValue () {
return obj.getName();
}
public void setValue (Object val) throws IllegalAccessException,
IllegalArgumentException, InvocationTargetException {
if (!canWrite())
throw new IllegalAccessException();
if (!(val instanceof String))
throw new IllegalArgumentException();
try {
obj.rename ((String)val);
} catch (IOException ex) {
String msg = null;
if ((ex.getLocalizedMessage() == null) ||
(ex.getLocalizedMessage().equals(ex.getMessage()))) {
msg = NbBundle.getMessage (DataNode.class, "MSG_renameError", obj.getName(), val); // NOI18N
} else {
msg = ex.getLocalizedMessage();
}
ErrorManager.getDefault().annotate (ex, ErrorManager.USER, null, msg, null, null);
throw new InvocationTargetException(ex);
}
}
public boolean canWrite () {
return obj.isRenameAllowed();
}
// #33296 - suppress custom editor
public Object getValue(String key) {
if ("suppressCustomEditor".equals (key)) { //NOI18N
return Boolean.TRUE;
} else {
return super.getValue (key);
}
}
};
return p;
}
/** Support for firing property change.
* @param ev event describing the change
*/
void fireChange(final PropertyChangeEvent ev) {
Mutex.EVENT.writeAccess(new Runnable() {
public void run() {
if (DataFolder.PROP_CHILDREN.equals(ev.getPropertyName())) {
// the node is not interested in children changes
return;
}
if (DataObject.PROP_PRIMARY_FILE.equals(ev.getPropertyName())) {
// the node is not interested in children changes
propL.updateStatusListener();
setName(obj.getName(), false);
return;
}
if (DataObject.PROP_NAME.equals(ev.getPropertyName())) {
DataNode.super.setName(obj.getName());
updateDisplayName();
return;
}
if (DataObject.PROP_COOKIE.equals(ev.getPropertyName())) {
fireCookieChange();
//return;
}
// if the DataOjbect is not valid the node should be
// removed
if (DataObject.PROP_VALID.equals(ev.getPropertyName())) {
Object newVal = ev.getNewValue();
if ((newVal instanceof Boolean) && (!((Boolean) newVal).booleanValue())) {
fireNodeDestroyed();
}
return;
}
/*See #31413*/
List transmitProperties = Arrays.asList(new String[] {
DataObject.PROP_NAME, DataObject.PROP_FILES, DataObject.PROP_TEMPLATE});
if (transmitProperties.contains(ev.getPropertyName())) {
firePropertyChange(ev.getPropertyName(), ev.getOldValue(), ev.getNewValue());
}
}
});
}
/** Handle for location of given data object.
* @return handle that remembers the data object.
*/
public Handle getHandle () {
return new ObjectHandle(obj, obj.isValid() ? (this != obj.getNodeDelegate()) : /* to be safe */ true);
}
/** Access method to fire icon change.
*/
final void fireChangeAccess (boolean icon, boolean name) {
if (name) {
fireDisplayNameChange (null, null);
}
if (icon) {
fireIconChange ();
}
}
/** Determine whether file extensions should be shown by default.
* By default, no.
* @return true if so
*/
public static boolean getShowFileExtensions () {
return showFileExtensions;
}
/** Set whether file extensions should be shown by default.
* @param s true if so
*/
public static void setShowFileExtensions (boolean s) {
boolean refresh = ( showFileExtensions != s );
showFileExtensions = s;
if ( refresh ) {
// refresh current nodes display name
RequestProcessor.postRequest(new Runnable () {
public void run () {
Iterator it = DataObjectPool.getPOOL().getActiveDataObjects();
while ( it.hasNext() ) {
DataObject obj = ((DataObjectPool.Item)it.next()).getDataObjectOrNull();
if ( obj != null && obj.getNodeDelegate() instanceof DataNode ) {
((DataNode)obj.getNodeDelegate()).updateDisplayName();
}
}
}
}, 300, Thread.MIN_PRIORITY);
}
}
/** Request processor task to update a bunch of names/icons.
* Potentially faster to do many nodes at once; see #16478.
*/
private static RequestProcessor.Task refreshNamesIconsTask = null;
/** nodes which should be refreshed */
private static Set refreshNameNodes = null; // Set
private static Set refreshIconNodes = null; // Set
/** whether the task is current scheduled and will still look in above sets */
private static boolean refreshNamesIconsRunning = false;
private static final Object refreshNameIconLock = "DataNode.refreshNameIconLock"; // NOI18N
/** Property listener on data object that delegates all changes of
* properties to this node.
*/
private class PropL extends Object
implements PropertyChangeListener, FileStatusListener, Runnable {
/** weak version of this listener */
private FileStatusListener weakL;
/** previous filesystem we were attached to */
private FileSystem previous;
public PropL () {
updateStatusListener ();
}
public void propertyChange (PropertyChangeEvent ev) {
fireChange (ev);
}
/** Updates listening on a status of filesystem.
*/
private void updateStatusListener () {
if (previous != null) {
previous.removeFileStatusListener (weakL);
}
try {
previous = obj.getPrimaryFile ().getFileSystem ();
if (weakL == null) {
weakL = org.openide.filesystems.FileUtil.weakFileStatusListener (this, null);
}
previous.addFileStatusListener (weakL);
} catch (FileStateInvalidException ex) {
previous = null;
}
}
/** Notifies listener about change in annotataion of a few files.
* @param ev event describing the change
*/
public void annotationChanged (FileStatusEvent ev) {
// #16541: listen for changes in both primary and secondary files
boolean thisChanged = false;
Iterator it = obj.files().iterator();
while (it.hasNext()) {
FileObject fo = (FileObject)it.next();
if (ev.hasChanged(fo)) {
thisChanged = true;
break;
}
}
if (thisChanged) {
// #12368: fire display name & icon changes asynch
synchronized (refreshNameIconLock) {
boolean post = false;
if (ev.isNameChange()) {
if (refreshNameNodes == null) {
refreshNameNodes = new HashSet();
}
post |= refreshNameNodes.add(DataNode.this);
}
if (ev.isIconChange()) {
if (refreshIconNodes == null) {
refreshIconNodes = new HashSet();
}
post |= refreshIconNodes.add(DataNode.this);
}
if (post && !refreshNamesIconsRunning) {
refreshNamesIconsRunning = true;
if (refreshNamesIconsTask == null) {
refreshNamesIconsTask = RequestProcessor.postRequest(this);
} else {
// Should be OK even if it is running right now.
// (Cf. RequestProcessorTest.testScheduleWhileRunning.)
refreshNamesIconsTask.schedule(0);
}
}
}
}
}
/** Refreshes names and icons for a whole batch of data nodes at once.
*/
public void run() {
DataNode[] _refreshNameNodes, _refreshIconNodes;
synchronized (refreshNameIconLock) {
if (refreshNameNodes != null) {
_refreshNameNodes = (DataNode[])refreshNameNodes.toArray(new DataNode[refreshNameNodes.size()]);
refreshNameNodes.clear();
} else {
_refreshNameNodes = new DataNode[0];
}
if (refreshIconNodes != null) {
_refreshIconNodes = (DataNode[])refreshIconNodes.toArray(new DataNode[refreshIconNodes.size()]);
refreshIconNodes.clear();
} else {
_refreshIconNodes = new DataNode[0];
}
refreshNamesIconsRunning = false;
}
for (int i = 0; i < _refreshNameNodes.length; i++) {
_refreshNameNodes[i].fireChangeAccess(false, true);
}
for (int i = 0; i < _refreshIconNodes.length; i++) {
_refreshIconNodes[i].fireChangeAccess(true, false);
}
}
}
/** Handle for data object nodes */
private static class ObjectHandle extends Object implements Handle {
private FileObject obj;
private boolean clone;
static final long serialVersionUID =6616060729084681518L;
public ObjectHandle (DataObject obj, boolean clone) {
this.obj = obj.getPrimaryFile ();
this.clone = clone;
}
public Node getNode () throws IOException {
if (obj == null) {
// Serialization problem? Seems to occur frequently with connection support:
// java.lang.IllegalArgumentException: Called DataObject.find on null
// at org.openide.loaders.DataObject.find(DataObject.java:435)
// at org.openide.loaders.DataNode$ObjectHandle.getNode(DataNode.java:757)
// at org.netbeans.modules.java.JavaDataObject$PersistentConnectionHandle.getNode(JavaDataObject.java:977)
// at org.openide.loaders.ConnectionSupport$Pair.getNode(ConnectionSupport.java:357)
// at org.openide.loaders.ConnectionSupport.register(ConnectionSupport.java:94)
// at org.netbeans.modules.java.codesync.SourceConnectionSupport.registerDependency(SourceConnectionSupport.java:475)
// at org.netbeans.modules.java.codesync.SourceConnectionSupport.addDependency(SourceConnectionSupport.java:554)
// at org.netbeans.modules.java.codesync.ClassDependencyImpl.supertypesAdded(ClassDependencyImpl.java:241)
// at org.netbeans.modules.java.codesync.ClassDependencyImpl.refreshClass(ClassDependencyImpl.java:121)
// at org.netbeans.modules.java.codesync.SourceConnectionSupport.refreshLinks(SourceConnectionSupport.java:357)
// at org.netbeans.modules.java.codesync.SourceConnectionSupport.access$000(SourceConnectionSupport.java:44)
// at org.netbeans.modules.java.codesync.SourceConnectionSupport$2.run(SourceConnectionSupport.java:223)
throw new IOException("File could not be restored"); // NOI18N
}
Node n = DataObject.find (obj).getNodeDelegate ();
return clone ? n.cloneNode () : n;
}
}
/** Wrapping class for obj.files(). Used in getIcon() and getDisplayName()
to have something lazy to pass to annotateIcon() and annotateName()
instead of calling obj.files() immediately. */
private class LazyFilesSet implements Set {
private Set obj_files;
synchronized private void lazyInitialization () {
obj_files = obj.files();
}
public boolean add(Object o) {
lazyInitialization();
return obj_files.add(o);
}
public boolean addAll(Collection c) {
lazyInitialization();
return obj_files.addAll(c);
}
public void clear() {
lazyInitialization();
obj_files.clear();
}
public boolean contains(Object o) {
lazyInitialization();
return obj_files.contains(o);
}
public boolean containsAll(Collection c) {
lazyInitialization();
return obj_files.containsAll(c);
}
public boolean isEmpty() {
lazyInitialization();
return obj_files.isEmpty();
}
public Iterator iterator() {
return new FilesIterator ();
}
public boolean remove(Object o) {
lazyInitialization();
return obj_files.remove(o);
}
public boolean removeAll(Collection c) {
lazyInitialization();
return obj_files.removeAll(c);
}
public boolean retainAll(Collection c) {
lazyInitialization();
return obj_files.retainAll(c);
}
public int size() {
lazyInitialization();
return obj_files.size();
}
public Object[] toArray() {
lazyInitialization();
return obj_files.toArray();
}
public Object[] toArray(Object[] a) {
lazyInitialization();
return obj_files.toArray(a);
}
/** Iterator for FilesSet. It returns the primaryFile first and
* then initialize the delegate iterator for secondary files.
*/
private final class FilesIterator implements Iterator {
/** Was the first element (primary file) already returned?
*/
private boolean first = true;
/** Delegation iterator for secondary files. It is lazy initialized after
* the first element is returned.
*/
private Iterator itDelegate = null;
FilesIterator() {}
public boolean hasNext() {
return first ? true : getIteratorDelegate().hasNext();
}
public Object next() {
if (first) {
first = false;
return obj.getPrimaryFile ();
}
else {
return getIteratorDelegate().next();
}
}
public void remove() {
getIteratorDelegate().remove();
}
/** Initialize the delegation iterator.
*/
private Iterator getIteratorDelegate() {
if (itDelegate == null) {
lazyInitialization ();
// this should return iterator of all files of the MultiDataObject...
itDelegate = obj_files.iterator ();
// ..., so it is necessary to skip the primary file
itDelegate.next();
}
return itDelegate;
}
}
}
}