Quellverzeichnis List.java Interaktion und
PortierbarkeitJAVA

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package java.awt;

import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.FocusListener;
import java.awt.event.ItemEvent;
import java.awt.event.ItemListener;
import java.awt.peer.ListPeer;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.io.Serial;
import java.util.EventListener;
import java.util.Locale;
import java.util.Vector;

import javax.accessibility.Accessible;
import javax.accessibility.AccessibleContext;
import javax.accessibility.AccessibleRole;
import javax.accessibility.AccessibleSelection;
import javax.accessibility.AccessibleState;
import javax.accessibility.AccessibleStateSet;

/**
* The {@code List} component presents the user with a
* scrolling list of text items. The list can be set up so that
* the user can choose either one item or multiple items.
* 
* For example, the code . . .
*
* <hr><blockquote><pre>
* List lst = new List(4, false);
* lst.add("Mercury");
* lst.add("Venus");
* lst.add("Earth");
* lst.add("JavaSoft");
* lst.add("Mars");
* lst.add("Jupiter");
* lst.add("Saturn");
* lst.add("Uranus");
* lst.add("Neptune");
* lst.add("Pluto");
* cnt.add(lst);
* </pre></blockquote><hr>
* 
* where {@code cnt} is a container, produces the following
* scrolling list:
* 
* <img src="doc-files/List-1.gif"
* alt="Shows a list containing: Venus, Earth, JavaSoft, and Mars. Javasoft is
* selected." style="margin: 7px 10px;">
* 
* If the List allows multiple selections, then clicking on
* an item that is already selected deselects it. In the preceding
* example, only one item from the scrolling list can be selected
* at a time, since the second argument when creating the new scrolling
* list is {@code false}. If the List does not allow multiple
* selections, selecting an item causes any other selected item
* to be deselected.
* 
* Note that the list in the example shown was created with four visible
* rows. Once the list has been created, the number of visible rows
* cannot be changed. A default {@code List} is created with
* four rows, so that {@code lst = new List()} is equivalent to
* {@code list = new List(4, false)}.
* 
* Beginning with Java 1.1, the Abstract Window Toolkit
* sends the {@code List} object all mouse, keyboard, and focus events
* that occur over it. (The old AWT event model is being maintained
* only for backwards compatibility, and its use is discouraged.)
* 
* When an item is selected or deselected by the user, AWT sends an instance
* of {@code ItemEvent} to the list.
* When the user double-clicks on an item in a scrolling list,
* AWT sends an instance of {@code ActionEvent} to the
* list following the item event. AWT also generates an action event
* when the user presses the return key while an item in the
* list is selected.
* 
* If an application wants to perform some action based on an item
* in this list being selected or activated by the user, it should implement
* {@code ItemListener} or {@code ActionListener}
* as appropriate and register the new listener to receive
* events from this list.
* 
* For multiple-selection scrolling lists, it is considered a better
* user interface to use an external gesture (such as clicking on a
* button) to trigger the action.
* @author Sami Shaio
* @see java.awt.event.ItemEvent
* @see java.awt.event.ItemListener
* @see java.awt.event.ActionEvent
* @see java.awt.event.ActionListener
* @since 1.0
*/
public class List extends Component implements ItemSelectable, Accessible {
 /**
 * A vector created to contain items which will become
 * part of the List Component.
 *
 * @serial
 * @see #addItem(String)
 * @see #getItem(int)
 */
 Vector<String> items = new Vector<>();

 /**
 * This field will represent the number of visible rows in the
 * {@code List} Component. It is specified only once, and
 * that is when the list component is actually
 * created. It will never change.
 *
 * @serial
 * @see #getRows()
 */
 int rows = 0;

 /**
 * {@code multipleMode} is a variable that will
 * be set to {@code true} if a list component is to be set to
 * multiple selection mode, that is where the user can
 * select more than one item in a list at one time.
 * {@code multipleMode} will be set to false if the
 * list component is set to single selection, that is where
 * the user can only select one item on the list at any
 * one time.
 *
 * @serial
 * @see #isMultipleMode()
 * @see #setMultipleMode(boolean)
 */
 boolean multipleMode = false;

 /**
 * {@code selected} is an array that will contain
 * the indices of items that have been selected.
 *
 * @serial
 * @see #getSelectedIndexes()
 * @see #getSelectedIndex()
 */
 int[] selected = new int[0];

 /**
 * This variable contains the value that will be used
 * when trying to make a particular list item visible.
 *
 * @serial
 * @see #makeVisible(int)
 */
 int visibleIndex = -1;

 transient ActionListener actionListener;
 transient ItemListener itemListener;

 private static final String base = "list";
 private static int nameCounter = 0;

 /**
 * Use serialVersionUID from JDK 1.1 for interoperability.
 */
 @Serial
 private static final long serialVersionUID = -3304312411574666869L;

 /**
 * Creates a new scrolling list.
 * By default, there are four visible lines and multiple selections are
 * not allowed. Note that this is a convenience method for
 * {@code List(0, false)}. Also note that the number of visible
 * lines in the list cannot be changed after it has been created.
 * @throws HeadlessException if GraphicsEnvironment.isHeadless()
 * returns true.
 * @see java.awt.GraphicsEnvironment#isHeadless
 */
 public List() throws HeadlessException {
 this(0, false);
 }

 /**
 * Creates a new scrolling list initialized with the specified
 * number of visible lines. By default, multiple selections are
 * not allowed. Note that this is a convenience method for
 * {@code List(rows, false)}. Also note that the number
 * of visible rows in the list cannot be changed after it has
 * been created.
 * @param rows the number of items to show.
 * @throws HeadlessException if GraphicsEnvironment.isHeadless()
 * returns true.
 * @see java.awt.GraphicsEnvironment#isHeadless
 * @since 1.1
 */
 public List(int rows) throws HeadlessException {
 this(rows, false);
 }

 /**
 * The default number of visible rows is 4. A list with
 * zero rows is unusable and unsightly.
 */
 static final int DEFAULT_VISIBLE_ROWS = 4;

 /**
 * Creates a new scrolling list initialized to display the specified
 * number of rows. Note that if zero rows are specified, then
 * the list will be created with a default of four rows.
 * Also note that the number of visible rows in the list cannot
 * be changed after it has been created.
 * If the value of {@code multipleMode} is
 * {@code true}, then the user can select multiple items from
 * the list. If it is {@code false}, only one item at a time
 * can be selected.
 * @param rows the number of items to show.
 * @param multipleMode if {@code true},
 * then multiple selections are allowed;
 * otherwise, only one item can be selected at a time.
 * @throws HeadlessException if GraphicsEnvironment.isHeadless()
 * returns true.
 * @see java.awt.GraphicsEnvironment#isHeadless
 */
 public List(int rows, boolean multipleMode) throws HeadlessException {
 GraphicsEnvironment.checkHeadless();
 this.rows = (rows != 0) ? rows : DEFAULT_VISIBLE_ROWS;
 this.multipleMode = multipleMode;
 }

 /**
 * Construct a name for this component. Called by
 * {@code getName} when the name is {@code null}.
 */
 String constructComponentName() {
 synchronized (List.class) {
 return base + nameCounter++;
 }
 }

 /**
 * Creates the peer for the list. The peer allows us to modify the
 * list's appearance without changing its functionality.
 */
 public void addNotify() {
 synchronized (getTreeLock()) {
 if (peer == null)
 peer = getComponentFactory().createList(this);
 super.addNotify();
 }
 }

 /**
 * Removes the peer for this list. The peer allows us to modify the
 * list's appearance without changing its functionality.
 */
 public void removeNotify() {
 synchronized (getTreeLock()) {
 ListPeer peer = (ListPeer)this.peer;
 if (peer != null) {
 selected = peer.getSelectedIndexes();
 }
 super.removeNotify();
 }
 }

 /**
 * Gets the number of items in the list.
 * @return the number of items in the list
 * @see #getItem
 * @since 1.1
 */
 public int getItemCount() {
 return countItems();
 }

 /**
 * Returns the number of items in the list.
 *
 * @return the number of items in the list
 * @deprecated As of JDK version 1.1,
 * replaced by {@code getItemCount()}.
 */
 @Deprecated
 public int countItems() {
 return items.size();
 }

 /**
 * Gets the item associated with the specified index.
 * @return an item that is associated with
 * the specified index
 * @param index the position of the item
 * @see #getItemCount
 */
 public String getItem(int index) {
 return getItemImpl(index);
 }

 // NOTE: This method may be called by privileged threads.
 // We implement this functionality in a package-private method
 // to insure that it cannot be overridden by client subclasses.
 // DO NOT INVOKE CLIENT CODE ON THIS THREAD!
 final String getItemImpl(int index) {
 return items.elementAt(index);
 }

 /**
 * Gets the items in the list.
 * @return a string array containing items of the list
 * @see #select
 * @see #deselect
 * @see #isIndexSelected
 * @since 1.1
 */
 public synchronized String[] getItems() {
 String[] itemCopies = new String[items.size()];
 items.copyInto(itemCopies);
 return itemCopies;
 }

 /**
 * Adds the specified item to the end of scrolling list.
 * @param item the item to be added
 * @since 1.1
 */
 public void add(String item) {
 addItem(item);
 }

 /**
 * Adds the specified item to the end of the list.
 *
 * @param item the item to be added
 * @deprecated replaced by {@code add(String)}.
 */
 @Deprecated
 public void addItem(String item) {
 addItem(item, -1);
 }

 /**
 * Adds the specified item to the scrolling list
 * at the position indicated by the index. The index is
 * zero-based. If the value of the index is less than zero,
 * or if the value of the index is greater than or equal to
 * the number of items in the list, then the item is added
 * to the end of the list.
 * @param item the item to be added;
 * if this parameter is {@code null} then the item is
 * treated as an empty string, {@code ""}
 * @param index the position at which to add the item
 * @since 1.1
 */
 public void add(String item, int index) {
 addItem(item, index);
 }

 /**
 * Adds the specified item to the list
 * at the position indicated by the index.
 *
 * @param item the item to be added
 * @param index the position at which to add the item
 * @deprecated replaced by {@code add(String, int)}.
 */
 @Deprecated
 public synchronized void addItem(String item, int index) {
 if (index < -1 || index >= items.size()) {
 index = -1;
 }

 if (item == null) {
 item = "";
 }

 if (index == -1) {
 items.addElement(item);
 } else {
 items.insertElementAt(item, index);
 }

 ListPeer peer = (ListPeer)this.peer;
 if (peer != null) {
 peer.add(item, index);
 }
 }

 /**
 * Replaces the item at the specified index in the scrolling list
 * with the new string.
 * @param newValue a new string to replace an existing item
 * @param index the position of the item to replace
 * @throws ArrayIndexOutOfBoundsException if {@code index}
 * is out of range
 */
 public synchronized void replaceItem(String newValue, int index) {
 remove(index);
 add(newValue, index);
 }

 /**
 * Removes all items from this list.
 * @see #remove
 * @see #delItems
 * @since 1.1
 */
 public void removeAll() {
 clear();
 }

 /**
 * @deprecated As of JDK version 1.1,
 * replaced by {@code removeAll()}.
 */
 @Deprecated
 public synchronized void clear() {
 ListPeer peer = (ListPeer)this.peer;
 if (peer != null) {
 peer.removeAll();
 }
 items = new Vector<>();
 selected = new int[0];
 }

 /**
 * Removes the first occurrence of an item from the list.
 * If the specified item is selected, and is the only selected
 * item in the list, the list is set to have no selection.
 * @param item the item to remove from the list
 * @throws IllegalArgumentException
 * if the item doesn't exist in the list
 * @since 1.1
 */
 public synchronized void remove(String item) {
 int index = items.indexOf(item);
 if (index < 0) {
 throw new IllegalArgumentException("item " + item +
 " not found in list");
 } else {
 remove(index);
 }
 }

 /**
 * Removes the item at the specified position
 * from this scrolling list.
 * If the item with the specified position is selected, and is the
 * only selected item in the list, the list is set to have no selection.
 * @param position the index of the item to delete
 * @see #add(String, int)
 * @since 1.1
 * @throws ArrayIndexOutOfBoundsException
 * if the {@code position} is less than 0 or
 * greater than {@code getItemCount()-1}
 */
 public void remove(int position) {
 delItem(position);
 }

 /**
 * Removes the item at the specified position.
 *
 * @param position the index of the item to delete
 * @deprecated replaced by {@code remove(String)}
 * and {@code remove(int)}.
 */
 @Deprecated
 public void delItem(int position) {
 delItems(position, position);
 }

 /**
 * Gets the index of the selected item on the list,
 *
 * @return the index of the selected item;
 * if no item is selected, or if multiple items are
 * selected, {@code -1} is returned.
 * @see #select
 * @see #deselect
 * @see #isIndexSelected
 */
 public synchronized int getSelectedIndex() {
 int[] sel = getSelectedIndexes();
 return (sel.length == 1) ? sel[0] : -1;
 }

 /**
 * Gets the selected indexes on the list.
 *
 * @return an array of the selected indexes on this scrolling list;
 * if no item is selected, a zero-length array is returned.
 * @see #select
 * @see #deselect
 * @see #isIndexSelected
 */
 public synchronized int[] getSelectedIndexes() {
 ListPeer peer = (ListPeer)this.peer;
 if (peer != null) {
 selected = peer.getSelectedIndexes();
 }
 return selected.clone();
 }

 /**
 * Gets the selected item on this scrolling list.
 *
 * @return the selected item on the list;
 * if no item is selected, or if multiple items are
 * selected, {@code null} is returned.
 * @see #select
 * @see #deselect
 * @see #isIndexSelected
 */
 public synchronized String getSelectedItem() {
 int index = getSelectedIndex();
 return (index < 0) ? null : getItem(index);
 }

 /**
 * Gets the selected items on this scrolling list.
 *
 * @return an array of the selected items on this scrolling list;
 * if no item is selected, a zero-length array is returned.
 * @see #select
 * @see #deselect
 * @see #isIndexSelected
 */
 public synchronized String[] getSelectedItems() {
 int[] sel = getSelectedIndexes();
 String[] str = new String[sel.length];
 for (int i = 0 ; i < sel.length ; i++) {
 str[i] = getItem(sel[i]);
 }
 return str;
 }

 /**
 * Gets the selected items on this scrolling list in an array of Objects.
 * @return an array of {@code Object}s representing the
 * selected items on this scrolling list;
 * if no item is selected, a zero-length array is returned.
 * @see #getSelectedItems
 * @see ItemSelectable
 */
 public Object[] getSelectedObjects() {
 return getSelectedItems();
 }

 /**
 * Selects the item at the specified index in the scrolling list.
 *
 * Note that passing out of range parameters is invalid,
 * and will result in unspecified behavior.
 *
 * Note that this method should be primarily used to
 * initially select an item in this component.
 * Programmatically calling this method will not trigger
 * an {@code ItemEvent}. The only way to trigger an
 * {@code ItemEvent} is by user interaction.
 *
 * @param index the position of the item to select
 * @see #getSelectedItem
 * @see #deselect
 * @see #isIndexSelected
 */
 public void select(int index) {
 // Bug #4059614: select can't be synchronized while calling the peer,
 // because it is called from the Window Thread. It is sufficient to
 // synchronize the code that manipulates 'selected' except for the
 // case where the peer changes. To handle this case, we simply
 // repeat the selection process.

 ListPeer peer;
 do {
 peer = (ListPeer)this.peer;
 if (peer != null) {
 peer.select(index);
 return;
 }

 synchronized(this)
 {
 boolean alreadySelected = false;

 for (int i = 0 ; i < selected.length ; i++) {
 if (selected[i] == index) {
 alreadySelected = true;
 break;
 }
 }

 if (!alreadySelected) {
 if (!multipleMode) {
 selected = new int[1];
 selected[0] = index;
 } else {
 int[] newsel = new int[selected.length + 1];
 System.arraycopy(selected, 0, newsel, 0,
 selected.length);
 newsel[selected.length] = index;
 selected = newsel;
 }
 }
 }
 } while (peer != this.peer);
 }

 /**
 * Deselects the item at the specified index.
 * 
 * Note that passing out of range parameters is invalid,
 * and will result in unspecified behavior.
 * 
 * If the item at the specified index is not selected,
 * then the operation is ignored.
 * @param index the position of the item to deselect
 * @see #select
 * @see #getSelectedItem
 * @see #isIndexSelected
 */
 public synchronized void deselect(int index) {
 ListPeer peer = (ListPeer)this.peer;
 if (peer != null) {
 if (isMultipleMode() || (getSelectedIndex() == index)) {
 peer.deselect(index);
 }
 }

 for (int i = 0 ; i < selected.length ; i++) {
 if (selected[i] == index) {
 int[] newsel = new int[selected.length - 1];
 System.arraycopy(selected, 0, newsel, 0, i);
 System.arraycopy(selected, i+1, newsel, i, selected.length - (i+1));
 selected = newsel;
 return;
 }
 }
 }

 /**
 * Determines if the specified item in this scrolling list is
 * selected.
 * @param index the item to be checked
 * @return {@code true} if the specified item has been
 * selected; {@code false} otherwise
 * @see #select
 * @see #deselect
 * @since 1.1
 */
 public boolean isIndexSelected(int index) {
 return isSelected(index);
 }

 /**
 * Determines if the specified item in the list is selected.
 *
 * @param index specifies the item to be checked
 * @return {@code true} if the item is selected; otherwise {@code false}
 * @deprecated As of JDK version 1.1,
 * replaced by {@code isIndexSelected(int)}.
 */
 @Deprecated
 public boolean isSelected(int index) {
 int[] sel = getSelectedIndexes();
 for (int i = 0 ; i < sel.length ; i++) {
 if (sel[i] == index) {
 return true;
 }
 }
 return false;
 }

 /**
 * Gets the number of visible lines in this list. Note that
 * once the {@code List} has been created, this number
 * will never change.
 * @return the number of visible lines in this scrolling list
 */
 public int getRows() {
 return rows;
 }

 /**
 * Determines whether this list allows multiple selections.
 *
 * @return {@code true} if this list allows multiple
 * selections; otherwise, {@code false}
 * @see #setMultipleMode
 * @since 1.1
 */
 public boolean isMultipleMode() {
 return allowsMultipleSelections();
 }

 /**
 * Determines whether this list allows multiple selections.
 *
 * @return {@code true} if this list allows multiple
 * selections; otherwise {@code false}
 * @deprecated As of JDK version 1.1,
 * replaced by {@code isMultipleMode()}.
 */
 @Deprecated
 public boolean allowsMultipleSelections() {
 return multipleMode;
 }

 /**
 * Sets the flag that determines whether this list
 * allows multiple selections.
 * When the selection mode is changed from multiple-selection to
 * single-selection, the selected items change as follows:
 * If a selected item has the location cursor, only that
 * item will remain selected. If no selected item has the
 * location cursor, all items will be deselected.
 * @param b if {@code true} then multiple selections
 * are allowed; otherwise, only one item from
 * the list can be selected at once
 * @see #isMultipleMode
 * @since 1.1
 */
 public void setMultipleMode(boolean b) {
 setMultipleSelections(b);
 }

 /**
 * Enables or disables multiple selection mode for this list.
 *
 * @param b {@code true} to enable multiple mode, {@code false} otherwise
 * @deprecated As of JDK version 1.1,
 * replaced by {@code setMultipleMode(boolean)}.
 */
 @Deprecated
 public synchronized void setMultipleSelections(boolean b) {
 if (b != multipleMode) {
 multipleMode = b;
 ListPeer peer = (ListPeer)this.peer;
 if (peer != null) {
 peer.setMultipleMode(b);
 }
 }
 }

 /**
 * Gets the index of the item that was last made visible by
 * the method {@code makeVisible}.
 * @return the index of the item that was last made visible
 * @see #makeVisible
 */
 public int getVisibleIndex() {
 return visibleIndex;
 }

 /**
 * Makes the item at the specified index visible.
 * @param index the position of the item
 * @see #getVisibleIndex
 */
 public synchronized void makeVisible(int index) {
 visibleIndex = index;
 ListPeer peer = (ListPeer)this.peer;
 if (peer != null) {
 peer.makeVisible(index);
 }
 }

 /**
 * Gets the preferred dimensions for a list with the specified
 * number of rows.
 * @param rows number of rows in the list
 * @return the preferred dimensions for displaying this scrolling list
 * given that the specified number of rows must be visible
 * @see java.awt.Component#getPreferredSize
 * @since 1.1
 */
 public Dimension getPreferredSize(int rows) {
 return preferredSize(rows);
 }

 /**
 * Returns the preferred size of this component
 * assuming it has the specified number of rows.
 *
 * @param rows the number of rows
 * @return the preferred dimensions for displaying this list
 * @deprecated As of JDK version 1.1,
 * replaced by {@code getPreferredSize(int)}.
 */
 @Deprecated
 public Dimension preferredSize(int rows) {
 synchronized (getTreeLock()) {
 ListPeer peer = (ListPeer)this.peer;
 return (peer != null) ?
 peer.getPreferredSize(rows) :
 super.preferredSize();
 }
 }

 /**
 * Gets the preferred size of this scrolling list.
 * @return the preferred dimensions for displaying this scrolling list
 * @see java.awt.Component#getPreferredSize
 * @since 1.1
 */
 public Dimension getPreferredSize() {
 return preferredSize();
 }

 /**
 * @deprecated As of JDK version 1.1,
 * replaced by {@code getPreferredSize()}.
 */
 @Deprecated
 public Dimension preferredSize() {
 synchronized (getTreeLock()) {
 return (rows > 0) ?
 preferredSize(rows) :
 super.preferredSize();
 }
 }

 /**
 * Gets the minimum dimensions for a list with the specified
 * number of rows.
 * @param rows number of rows in the list
 * @return the minimum dimensions for displaying this scrolling list
 * given that the specified number of rows must be visible
 * @see java.awt.Component#getMinimumSize
 * @since 1.1
 */
 public Dimension getMinimumSize(int rows) {
 return minimumSize(rows);
 }

 /**
 * Returns the minimum dimensions for the list
 * with the specified number of rows.
 *
 * @param rows the number of rows in the list
 * @return the minimum dimensions for displaying this list
 * @deprecated As of JDK version 1.1,
 * replaced by {@code getMinimumSize(int)}.
 */
 @Deprecated
 public Dimension minimumSize(int rows) {
 synchronized (getTreeLock()) {
 ListPeer peer = (ListPeer)this.peer;
 return (peer != null) ?
 peer.getMinimumSize(rows) :
 super.minimumSize();
 }
 }

 /**
 * Determines the minimum size of this scrolling list.
 * @return the minimum dimensions needed
 * to display this scrolling list
 * @see java.awt.Component#getMinimumSize()
 * @since 1.1
 */
 public Dimension getMinimumSize() {
 return minimumSize();
 }

 /**
 * @deprecated As of JDK version 1.1,
 * replaced by {@code getMinimumSize()}.
 */
 @Deprecated
 public Dimension minimumSize() {
 synchronized (getTreeLock()) {
 return (rows > 0) ? minimumSize(rows) : super.minimumSize();
 }
 }

 /**
 * Adds the specified item listener to receive item events from
 * this list. Item events are sent in response to user input, but not
 * in response to calls to {@code select} or {@code deselect}.
 * If listener {@code l} is {@code null},
 * no exception is thrown and no action is performed.
 * Refer to <a href="doc-files/AWTThreadIssues.html#ListenersThreads"
 * >AWT Threading Issues</a> for details on AWT's threading model.
 *
 * @param l the item listener
 * @see #removeItemListener
 * @see #getItemListeners
 * @see #select
 * @see #deselect
 * @see java.awt.event.ItemEvent
 * @see java.awt.event.ItemListener
 * @since 1.1
 */
 public synchronized void addItemListener(ItemListener l) {
 if (l == null) {
 return;
 }
 itemListener = AWTEventMulticaster.add(itemListener, l);
 newEventsOnly = true;
 }

 /**
 * Removes the specified item listener so that it no longer
 * receives item events from this list.
 * If listener {@code l} is {@code null},
 * no exception is thrown and no action is performed.
 * Refer to <a href="doc-files/AWTThreadIssues.html#ListenersThreads"
 * >AWT Threading Issues</a> for details on AWT's threading model.
 *
 * @param l the item listener
 * @see #addItemListener
 * @see #getItemListeners
 * @see java.awt.event.ItemEvent
 * @see java.awt.event.ItemListener
 * @since 1.1
 */
 public synchronized void removeItemListener(ItemListener l) {
 if (l == null) {
 return;
 }
 itemListener = AWTEventMulticaster.remove(itemListener, l);
 }

 /**
 * Returns an array of all the item listeners
 * registered on this list.
 *
 * @return all of this list's {@code ItemListener}s
 * or an empty array if no item
 * listeners are currently registered
 *
 * @see #addItemListener
 * @see #removeItemListener
 * @see java.awt.event.ItemEvent
 * @see java.awt.event.ItemListener
 * @since 1.4
 */
 public synchronized ItemListener[] getItemListeners() {
 return getListeners(ItemListener.class);
 }

 /**
 * Adds the specified action listener to receive action events from
 * this list. Action events occur when a user double-clicks
 * on a list item or types Enter when the list has the keyboard
 * focus.
 * 
 * If listener {@code l} is {@code null},
 * no exception is thrown and no action is performed.
 * Refer to <a href="doc-files/AWTThreadIssues.html#ListenersThreads"
 * >AWT Threading Issues</a> for details on AWT's threading model.
 *
 * @param l the action listener
 * @see #removeActionListener
 * @see #getActionListeners
 * @see java.awt.event.ActionEvent
 * @see java.awt.event.ActionListener
 * @since 1.1
 */
 public synchronized void addActionListener(ActionListener l) {
 if (l == null) {
 return;
 }
 actionListener = AWTEventMulticaster.add(actionListener, l);
 newEventsOnly = true;
 }

 /**
 * Removes the specified action listener so that it no longer
 * receives action events from this list. Action events
 * occur when a user double-clicks on a list item.
 * If listener {@code l} is {@code null},
 * no exception is thrown and no action is performed.
 * Refer to <a href="doc-files/AWTThreadIssues.html#ListenersThreads"
 * >AWT Threading Issues</a> for details on AWT's threading model.
 *
 * @param l the action listener
 * @see #addActionListener
 * @see #getActionListeners
 * @see java.awt.event.ActionEvent
 * @see java.awt.event.ActionListener
 * @since 1.1
 */
 public synchronized void removeActionListener(ActionListener l) {
 if (l == null) {
 return;
 }
 actionListener = AWTEventMulticaster.remove(actionListener, l);
 }

 /**
 * Returns an array of all the action listeners
 * registered on this list.
 *
 * @return all of this list's {@code ActionListener}s
 * or an empty array if no action
 * listeners are currently registered
 *
 * @see #addActionListener
 * @see #removeActionListener
 * @see java.awt.event.ActionEvent
 * @see java.awt.event.ActionListener
 * @since 1.4
 */
 public synchronized ActionListener[] getActionListeners() {
 return getListeners(ActionListener.class);
 }

 /**
 * Returns an array of all the objects currently registered
 * as <code>FooListener</code>s
 * upon this {@code List}.
 * <code>FooListener</code>s are registered using the
 * <code>addFooListener</code> method.
 *
 * 
 * You can specify the {@code listenerType} argument
 * with a class literal, such as
 * <code>FooListener.class</code>.
 * For example, you can query a
 * {@code List l}
 * for its item listeners with the following code:
 *
 * <pre>ItemListener[] ils = (ItemListener[])(l.getListeners(ItemListener.class));</pre>
 *
 * 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>FooListener</code>s on this list,
 * or an empty array if no such
 * listeners have been added
 * @throws ClassCastException if {@code listenerType}
 * doesn't specify a class or interface that implements
 * {@code java.util.EventListener}
 *
 * @see #getItemListeners
 * @since 1.3
 */
 public <T extends EventListener> T[] getListeners(Class<T> listenerType) {
 EventListener l = null;
 if (listenerType == ActionListener.class) {
 l = actionListener;
 } else if (listenerType == ItemListener.class) {
 l = itemListener;
 } else {
 return super.getListeners(listenerType);
 }
 return AWTEventMulticaster.getListeners(l, listenerType);
 }

 // REMIND: remove when filtering is done at lower level
 boolean eventEnabled(AWTEvent e) {
 switch(e.id) {
 case ActionEvent.ACTION_PERFORMED:
 if ((eventMask & AWTEvent.ACTION_EVENT_MASK) != 0 ||
 actionListener != null) {
 return true;
 }
 return false;
 case ItemEvent.ITEM_STATE_CHANGED:
 if ((eventMask & AWTEvent.ITEM_EVENT_MASK) != 0 ||
 itemListener != null) {
 return true;
 }
 return false;
 default:
 break;
 }
 return super.eventEnabled(e);
 }

 /**
 * Processes events on this scrolling list. If an event is
 * an instance of {@code ItemEvent}, it invokes the
 * {@code processItemEvent} method. Else, if the
 * event is an instance of {@code ActionEvent},
 * it invokes {@code processActionEvent}.
 * If the event is not an item event or an action event,
 * it invokes {@code processEvent} on the superclass.
 * Note that if the event parameter is {@code null}
 * the behavior is unspecified and may result in an
 * exception.
 *
 * @param e the event
 * @see java.awt.event.ActionEvent
 * @see java.awt.event.ItemEvent
 * @see #processActionEvent
 * @see #processItemEvent
 * @since 1.1
 */
 protected void processEvent(AWTEvent e) {
 if (e instanceof ItemEvent) {
 processItemEvent((ItemEvent)e);
 return;
 } else if (e instanceof ActionEvent) {
 processActionEvent((ActionEvent)e);
 return;
 }
 super.processEvent(e);
 }

 /**
 * Processes item events occurring on this list by
 * dispatching them to any registered
 * {@code ItemListener} objects.
 * 
 * This method is not called unless item events are
 * enabled for this component. Item events are enabled
 * when one of the following occurs:
 * <ul>
 * <li>An {@code ItemListener} object is registered
 * via {@code addItemListener}.
 * <li>Item events are enabled via {@code enableEvents}.
 * </ul>
 * Note that if the event parameter is {@code null}
 * the behavior is unspecified and may result in an
 * exception.
 *
 * @param e the item event
 * @see java.awt.event.ItemEvent
 * @see java.awt.event.ItemListener
 * @see #addItemListener
 * @see java.awt.Component#enableEvents
 * @since 1.1
 */
 protected void processItemEvent(ItemEvent e) {
 ItemListener listener = itemListener;
 if (listener != null) {
 listener.itemStateChanged(e);
 }
 }

 /**
 * Processes action events occurring on this component
 * by dispatching them to any registered
 * {@code ActionListener} objects.
 * 
 * This method is not called unless action events are
 * enabled for this component. Action events are enabled
 * when one of the following occurs:
 * <ul>
 * <li>An {@code ActionListener} object is registered
 * via {@code addActionListener}.
 * <li>Action events are enabled via {@code enableEvents}.
 * </ul>
 * Note that if the event parameter is {@code null}
 * the behavior is unspecified and may result in an
 * exception.
 *
 * @param e the action event
 * @see java.awt.event.ActionEvent
 * @see java.awt.event.ActionListener
 * @see #addActionListener
 * @see java.awt.Component#enableEvents
 * @since 1.1
 */
 protected void processActionEvent(ActionEvent e) {
 ActionListener listener = actionListener;
 if (listener != null) {
 listener.actionPerformed(e);
 }
 }

 /**
 * Returns the parameter string representing the state of this
 * scrolling list. This string is useful for debugging.
 * @return the parameter string of this scrolling list
 */
 protected String paramString() {
 return super.paramString() + ",selected=" + getSelectedItem();
 }

 /**
 * Deletes the list items in the specified index range.
 *
 * @param start the beginning index of the range to delete
 * @param end the ending index of the range to delete
 * @deprecated As of JDK version 1.1,
 * Not for public use in the future.
 * This method is expected to be retained only as a package
 * private method.
 */
 @Deprecated
 public synchronized void delItems(int start, int end) {
 for (int i = end; i >= start; i--) {
 items.removeElementAt(i);
 }
 ListPeer peer = (ListPeer)this.peer;
 if (peer != null) {
 peer.delItems(start, end);
 }
 }

 /*
 * Serialization support. Since the value of the selected
 * field isn't necessarily up to date, we sync it up with the
 * peer before serializing.
 */

 /**
 * The {@code List} component's
 * Serialized Data Version.
 *
 * @serial
 */
 private int listSerializedDataVersion = 1;

 /**
 * Writes default serializable fields to stream. Writes
 * a list of serializable {@code ItemListeners}
 * and {@code ActionListeners} as optional data.
 * The non-serializable listeners are detected and
 * no attempt is made to serialize them.
 *
 * @serialData {@code null} terminated sequence of 0
 * or more pairs; the pair consists of a {@code String}
 * and an {@code Object}; the {@code String}
 * indicates the type of object and is one of the
 * following:
 * {@code itemListenerK} indicating an
 * {@code ItemListener} object;
 * {@code actionListenerK} indicating an
 * {@code ActionListener} object
 *
 * @param s the {@code ObjectOutputStream} to write
 * @throws IOException if an I/O error occurs
 * @see AWTEventMulticaster#save(ObjectOutputStream, String, EventListener)
 * @see java.awt.Component#itemListenerK
 * @see java.awt.Component#actionListenerK
 * @see #readObject(ObjectInputStream)
 */
 @Serial
 private void writeObject(ObjectOutputStream s)
 throws IOException
 {
 synchronized (this) {
 ListPeer peer = (ListPeer)this.peer;
 if (peer != null) {
 selected = peer.getSelectedIndexes();
 }
 }
 s.defaultWriteObject();

 AWTEventMulticaster.save(s, itemListenerK, itemListener);
 AWTEventMulticaster.save(s, actionListenerK, actionListener);
 s.writeObject(null);
 }

 /**
 * Reads the {@code ObjectInputStream} and if it
 * isn't {@code null} adds a listener to receive
 * both item events and action events (as specified
 * by the key stored in the stream) fired by the
 * {@code List}.
 * Unrecognized keys or values will be ignored.
 *
 * @param s the {@code ObjectInputStream} to read
 * @throws ClassNotFoundException if the class of a serialized object could
 * not be found
 * @throws IOException if an I/O error occurs
 * @throws HeadlessException if {@code GraphicsEnvironment.isHeadless()}
 * returns {@code true}
 * @see #removeItemListener(ItemListener)
 * @see #addItemListener(ItemListener)
 * @see java.awt.GraphicsEnvironment#isHeadless
 * @see #writeObject(ObjectOutputStream)
 */
 @Serial
 private void readObject(ObjectInputStream s)
 throws ClassNotFoundException, IOException, HeadlessException
 {
 GraphicsEnvironment.checkHeadless();
 s.defaultReadObject();

 Object keyOrNull;
 while(null != (keyOrNull = s.readObject())) {
 String key = ((String)keyOrNull).intern();

 if (itemListenerK == key)
 addItemListener((ItemListener)(s.readObject()));

 else if (actionListenerK == key)
 addActionListener((ActionListener)(s.readObject()));

 else // skip value for unrecognized key
 s.readObject();
 }
 }

/////////////////
// Accessibility support
////////////////

 /**
 * Gets the {@code AccessibleContext} associated with this
 * {@code List}. For lists, the {@code AccessibleContext}
 * takes the form of an {@code AccessibleAWTList}.
 * A new {@code AccessibleAWTList} instance is created, if necessary.
 *
 * @return an {@code AccessibleAWTList} that serves as the
 * {@code AccessibleContext} of this {@code List}
 * @since 1.3
 */
 public AccessibleContext getAccessibleContext() {
 if (accessibleContext == null) {
 accessibleContext = new AccessibleAWTList();
 }
 return accessibleContext;
 }

 /**
 * This class implements accessibility support for the
 * {@code List} class. It provides an implementation of the
 * Java Accessibility API appropriate to list user-interface elements.
 * @since 1.3
 */
 protected class AccessibleAWTList extends AccessibleAWTComponent
 implements AccessibleSelection, ItemListener, ActionListener
 {
 /**
 * Use serialVersionUID from JDK 1.3 for interoperability.
 */
 @Serial
 private static final long serialVersionUID = 7924617370136012829L;

 /**
 * Constructs new {@code AccessibleAWTList}
 */
 public AccessibleAWTList() {
 super();
 List.this.addActionListener(this);
 List.this.addItemListener(this);
 }

 public void actionPerformed(ActionEvent event) {
 }

 public void itemStateChanged(ItemEvent event) {
 }

 /**
 * Get the state set of this object.
 *
 * @return an instance of AccessibleState containing the current state
 * of the object
 * @see AccessibleState
 */
 public AccessibleStateSet getAccessibleStateSet() {
 AccessibleStateSet states = super.getAccessibleStateSet();
 if (List.this.isMultipleMode()) {
 states.add(AccessibleState.MULTISELECTABLE);
 }
 return states;
 }

 /**
 * Get the role of this object.
 *
 * @return an instance of AccessibleRole describing the role of the
 * object
 * @see AccessibleRole
 */
 public AccessibleRole getAccessibleRole() {
 return AccessibleRole.LIST;
 }

 /**
 * Returns the Accessible child contained at the local coordinate
 * Point, if one exists.
 *
 * @return the Accessible at the specified location, if it exists
 */
 public Accessible getAccessibleAt(Point p) {
 return null; // fredxFIXME Not implemented yet
 }

 /**
 * Returns the number of accessible children in the object. If all
 * of the children of this object implement Accessible, than this
 * method should return the number of children of this object.
 *
 * @return the number of accessible children in the object.
 */
 public int getAccessibleChildrenCount() {
 return List.this.getItemCount();
 }

 /**
 * Return the nth Accessible child of the object.
 *
 * @param i zero-based index of child
 * @return the nth Accessible child of the object
 */
 public Accessible getAccessibleChild(int i) {
 synchronized(List.this) {
 if (i >= List.this.getItemCount()) {
 return null;
 } else {
 return new AccessibleAWTListChild(List.this, i);
 }
 }
 }

 /**
 * Get the AccessibleSelection associated with this object. In the
 * implementation of the Java Accessibility API for this class,
 * return this object, which is responsible for implementing the
 * AccessibleSelection interface on behalf of itself.
 *
 * @return this object
 */
 public AccessibleSelection getAccessibleSelection() {
 return this;
 }

 // AccessibleSelection methods

 /**
 * Returns the number of items currently selected.
 * If no items are selected, the return value will be 0.
 *
 * @return the number of items currently selected.
 */
 public int getAccessibleSelectionCount() {
 return List.this.getSelectedIndexes().length;
 }

 /**
 * Returns an Accessible representing the specified selected item
 * in the object. If there isn't a selection, or there are
 * fewer items selected than the integer passed in, the return
 * value will be null.
 *
 * @param i the zero-based index of selected items
 * @return an Accessible containing the selected item
 */
 public Accessible getAccessibleSelection(int i) {
 synchronized(List.this) {
 int len = getAccessibleSelectionCount();
 if (i < 0 || i >= len) {
 return null;
 } else {
 return getAccessibleChild(List.this.getSelectedIndexes()[i]);
 }
 }
 }

 /**
 * Returns true if the current child of this object is selected.
 *
 * @param i the zero-based index of the child in this Accessible
 * object.
 * @see AccessibleContext#getAccessibleChild
 */
 public boolean isAccessibleChildSelected(int i) {
 return List.this.isIndexSelected(i);
 }

 /**
 * Adds the specified selected item in the object to the object's
 * selection. If the object supports multiple selections,
 * the specified item is added to any existing selection, otherwise
 * it replaces any existing selection in the object. If the
 * specified item is already selected, this method has no effect.
 *
 * @param i the zero-based index of selectable items
 */
 public void addAccessibleSelection(int i) {
 List.this.select(i);
 }

 /**
 * Removes the specified selected item in the object from the object's
 * selection. If the specified item isn't currently selected, this
 * method has no effect.
 *
 * @param i the zero-based index of selectable items
 */
 public void removeAccessibleSelection(int i) {
 List.this.deselect(i);
 }

 /**
 * Clears the selection in the object, so that nothing in the
 * object is selected.
 */
 public void clearAccessibleSelection() {
 synchronized(List.this) {
 int[] selectedIndexes = List.this.getSelectedIndexes();
 if (selectedIndexes == null)
 return;
 for (int i = selectedIndexes.length - 1; i >= 0; i--) {
 List.this.deselect(selectedIndexes[i]);
 }
 }
 }

 /**
 * Causes every selected item in the object to be selected
 * if the object supports multiple selections.
 */
 public void selectAllAccessibleSelection() {
 synchronized(List.this) {
 for (int i = List.this.getItemCount() - 1; i >= 0; i--) {
 List.this.select(i);
 }
 }
 }

 /**
 * This class implements accessibility support for
 * List children. It provides an implementation of the
 * Java Accessibility API appropriate to list children
 * user-interface elements.
 * @since 1.3
 */
 protected class AccessibleAWTListChild extends AccessibleAWTComponent
 implements Accessible
 {
 /**
 * Use serialVersionUID from JDK 1.3 for interoperability.
 */
 @Serial
 private static final long serialVersionUID = 4412022926028300317L;

 // [[[FIXME]]] need to finish implementing this!!!

 /**
 * The parent {@code List}.
 */
 private List parent;

 /**
 * The index in the parent.
 */
 private int indexInParent;

 /**
 * Constructs new {@code AccessibleAWTListChild} with the given
 * parent {@code List} and 0-based index of this object in the parent.
 *
 * @param parent the parent {@code List}
 * @param indexInParent the index in the parent
 */
 public AccessibleAWTListChild(List parent, int indexInParent) {
 this.parent = parent;
 this.setAccessibleParent(parent);
 this.indexInParent = indexInParent;
 }

 //
 // required Accessible methods
 //
 /**
 * Gets the AccessibleContext for this object. In the
 * implementation of the Java Accessibility API for this class,
 * return this object, which acts as its own AccessibleContext.
 *
 * @return this object
 */
 public AccessibleContext getAccessibleContext() {
 return this;
 }

 //
 // required AccessibleContext methods
 //

 /**
 * Get the role of this object.
 *
 * @return an instance of AccessibleRole describing the role of
 * the object
 * @see AccessibleRole
 */
 public AccessibleRole getAccessibleRole() {
 return AccessibleRole.LIST_ITEM;
 }

 /**
 * Get the state set of this object. The AccessibleStateSet of an
 * object is composed of a set of unique AccessibleState's. A
 * change in the AccessibleStateSet of an object will cause a
 * PropertyChangeEvent to be fired for the
 * ACCESSIBLE_STATE_PROPERTY property.
 *
 * @return an instance of AccessibleStateSet containing the
 * current state set of the object
 * @see AccessibleStateSet
 * @see AccessibleState
 * @see #addPropertyChangeListener
 */
 public AccessibleStateSet getAccessibleStateSet() {
 AccessibleStateSet states = super.getAccessibleStateSet();
 if (parent.isIndexSelected(indexInParent)) {
 states.add(AccessibleState.SELECTED);
 }
 return states;
 }

 /**
 * Gets the locale of the component. If the component does not
 * have a locale, then the locale of its parent is returned.
 *
 * @return This component's locale. If this component does not have
 * a locale, the locale of its parent is returned.
 *
 * @throws IllegalComponentStateException
 * If the Component does not have its own locale and has not yet
 * been added to a containment hierarchy such that the locale can
 * be determined from the containing parent.
 */
 public Locale getLocale() {
 return parent.getLocale();
 }

 /**
 * Get the 0-based index of this object in its accessible parent.
 *
 * @return the 0-based index of this object in its parent; -1 if
 * this object does not have an accessible parent.
 *
 * @see #getAccessibleParent
 * @see #getAccessibleChildrenCount
 * @see #getAccessibleChild
 */
 public int getAccessibleIndexInParent() {
 return indexInParent;
 }

 /**
 * Returns the number of accessible children of the object.
 *
 * @return the number of accessible children of the object.
 */
 public int getAccessibleChildrenCount() {
 return 0; // list elements can't have children
 }

 /**
 * Return the specified Accessible child of the object. The
 * Accessible children of an Accessible object are zero-based,
 * so the first child of an Accessible child is at index 0, the
 * second child is at index 1, and so on.
 *
 * @param i zero-based index of child
 * @return the Accessible child of the object
 * @see #getAccessibleChildrenCount
 */
 public Accessible getAccessibleChild(int i) {
 return null; // list elements can't have children
 }

 //
 // AccessibleComponent delegation to parent List
 //

 /**
 * Get the background color of this object.
 *
 * @return the background color, if supported, of the object;
 * otherwise, null
 * @see #setBackground
 */
 public Color getBackground() {
 return parent.getBackground();
 }

 /**
 * Set the background color of this object.
 *
 * @param c the new Color for the background
 * @see #setBackground
 */
 public void setBackground(Color c) {
 parent.setBackground(c);
 }

 /**
 * Get the foreground color of this object.
 *
 * @return the foreground color, if supported, of the object;
 * otherwise, null
 * @see #setForeground
 */
 public Color getForeground() {
 return parent.getForeground();
 }

 /**
 * Set the foreground color of this object.
 *
 * @param c the new Color for the foreground
 * @see #getForeground
 */
 public void setForeground(Color c) {
 parent.setForeground(c);
 }

 /**
 * Get the Cursor of this object.
 *
 * @return the Cursor, if supported, of the object; otherwise, null
 * @see #setCursor
 */
 public Cursor getCursor() {
 return parent.getCursor();
 }

 /**
 * Set the Cursor of this object.
 * 
 * The method may have no visual effect if the Java platform
 * implementation and/or the native system do not support
 * changing the mouse cursor shape.
 * @param cursor the new Cursor for the object
 * @see #getCursor
 */
 public void setCursor(Cursor cursor) {
 parent.setCursor(cursor);
 }

 /**
 * Get the Font of this object.
 *
 * @return the Font, if supported, for the object; otherwise, null
 * @see #setFont
 */
 public Font getFont() {
 return parent.getFont();
 }

 /**
 * Set the Font of this object.
 *
 * @param f the new Font for the object
 * @see #getFont
 */
 public void setFont(Font f) {
 parent.setFont(f);
 }

 /**
 * Get the FontMetrics of this object.
 *
 * @param f the Font
 * @return the FontMetrics, if supported, the object; otherwise, null
 * @see #getFont
 */
 public FontMetrics getFontMetrics(Font f) {
 return parent.getFontMetrics(f);
 }

 /**
 * Determine if the object is enabled. Objects that are enabled
 * will also have the AccessibleState.ENABLED state set in their
 * AccessibleStateSet.
 *
 * @return true if object is enabled; otherwise, false
 * @see #setEnabled
 * @see AccessibleContext#getAccessibleStateSet
 * @see AccessibleState#ENABLED
 * @see AccessibleStateSet
 */
 public boolean isEnabled() {
 return parent.isEnabled();
 }

 /**
 * Set the enabled state of the object.
 *
 * @param b if true, enables this object; otherwise, disables it
 * @see #isEnabled
 */
 public void setEnabled(boolean b) {
 parent.setEnabled(b);
 }

 /**
 * Determine if the object is visible. Note: this means that the
 * object intends to be visible; however, it may not be
 * showing on the screen because one of the objects that this object
 * is contained by is currently not visible. To determine if an
 * object is showing on the screen, use isShowing().
 * Objects that are visible will also have the
 * AccessibleState.VISIBLE state set in their AccessibleStateSet.
 *
 * @return true if object is visible; otherwise, false
 * @see #setVisible
 * @see AccessibleContext#getAccessibleStateSet
 * @see AccessibleState#VISIBLE
 * @see AccessibleStateSet
 */
 public boolean isVisible() {
 // [[[FIXME]]] needs to work like isShowing() below
 return false;
 // return parent.isVisible();
 }

 /**
 * Set the visible state of the object.
 *
 * @param b if true, shows this object; otherwise, hides it
 * @see #isVisible
 */
 public void setVisible(boolean b) {
 // [[[FIXME]]] should scroll to item to make it show!
 parent.setVisible(b);
 }

 /**
 * Determine if the object is showing. This is determined by
 * checking the visibility of the object and visibility of the
 * object ancestors.
 * Note: this will return true even if the object is obscured
 * by another (for example, it to object is underneath a menu
 * that was pulled down).
 *
 * @return true if object is showing; otherwise, false
 */
 public boolean isShowing() {
 // [[[FIXME]]] only if it's showing!!!
 return false;
 // return parent.isShowing();
 }

 /**
 * Checks whether the specified point is within this object's
 * bounds, where the point's x and y coordinates are defined to
 * be relative to the coordinate system of the object.
 *
 * @param p the Point relative to the coordinate system of the
 * object
 * @return true if object contains Point; otherwise false
 * @see #getBounds
 */
 public boolean contains(Point p) {
 // [[[FIXME]]] - only if p is within the list element!!!
 return false;
 // return parent.contains(p);
 }

 /**
 * Returns the location of the object on the screen.
 *
 * @return location of object on screen; null if this object
 * is not on the screen
 * @see #getBounds
 * @see #getLocation
 */
 public Point getLocationOnScreen() {
 // [[[FIXME]]] sigh
 return null;
 }

 /**
 * Gets the location of the object relative to the parent in the
 * form of a point specifying the object's top-left corner in the
 * screen's coordinate space.
 *
 * @return An instance of Point representing the top-left corner of
 * the object's bounds in the coordinate space of the screen; null
 * if this object or its parent are not on the screen
 * @see #getBounds
--> --------------------

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--> --------------------

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Bemerkung:

Die farbliche Syntaxdarstellung ist noch experimentell.

Quellverzeichnis List.java Interaktion und PortierbarkeitJAVA

Haftungshinweis

Bemerkung:

Quellverzeichnis List.java Interaktion und
PortierbarkeitJAVA