gcc/libjava/javax/swing/DefaultListModel.java

/* DefaultListModel.java --
   Copyright (C) 2002, 2004, 2005  Free Software Foundation, Inc.

This file is part of GNU Classpath.

GNU Classpath is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
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As a special exception, the copyright holders of this library give you
permission to link this library with independent modules to produce an
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package javax.swing;

import java.util.Enumeration;
import java.util.Vector;

/**
 * This is a default subclass of the {@link AbstractListModel}, used by
 * {@link javax.swing.JList} and similar objects as the model of a list of
 * values. The implementation is based on an underlying {@link
 * java.util.Vector}.
 *
 * @author Andrew Selkirk
 * @author Graydon Hoare (graydon@redhat.com)
 */

public class DefaultListModel extends AbstractListModel
{
  private static final long serialVersionUID = 2315945659722172272L;

  /**
   * The vector of elements in this list model.
   */
  private Vector elements = new Vector();

  /**
   * Gets an element of the list at the provided index.
   *
   * @param index The index of the element to get
   *
   * @return The object at the given index
   *
   * @throws ArrayIndexOutOfBoundsException If the provided index is
   * outside the bounds of the list <code>[0, size())</code>
   */
  public Object elementAt(int index)
  {
    return elements.elementAt(index);
  }

  /**
   * Convert the list to a string representation.
   *
   * @return A string representation of the list
   */
  public String toString()
  {
    return elements.toString();
  }

  /**
   * Gets the first index of a particular element in the list.
   *
   * @param element The element to search for
   *
   * @return The first index in the list at which an object
   * <code>obj</code> exists such that <code>obj.equals(element)</code> is
   * <code>true</code>; if no such object exists, the method returns
   * <code>-1</code>
   */
  public int indexOf(Object element)
  {
    return elements.indexOf(element);
  }

  /**
   * Gets the first index of a particular element in a list which occurs
   * <em>at or after</em> a particular index.
   *
   * @param element The element to search for
   * @param startIndex The index to begin searching at
   *
   * @return The first index in the list, greater than or equal to
   * <code>startIndex</code>, at which an object <code>obj</code> exists
   * such that <code>obj.equals(element)</code> is <code>true</code>; if no
   * such object exists, the method returns <code>-1</code>
   */
  public int indexOf(Object element, int startIndex)
  {
    return elements.indexOf(element, startIndex);
  }

  /**
   * Gets the last index of a particular element in the list.
   *
   * @param element The element to search for
   *
   * @return The last index in the list at which an object
   * <code>obj</code> exists such that <code>obj.equals(element)</code> is
   * <code>true</code>; if no such object exists, the method returns
   * <code>-1</code>
   */
  public int lastIndexOf(Object element)
  {
    return elements.lastIndexOf(element);
  }

  /**
   * Gets the last index of a particular element in a list which occurs
   * <em>at or before</em> a particular index.
   *
   * @param element The element to search for
   * @param endIndex The index to finish searching at
   *
   * @return The last index in the list, less than to or equal to
   * <code>endIndexIndex</code>, at which an object <code>obj</code> exists
   * such that <code>obj.equals(element)</code> is <code>true</code>; if no
   * such object exists, the method returns <code>-1</code>
   */
  public int lastIndexOf(Object element, int endIndex)
  {
    return elements.lastIndexOf(element, endIndex);
  }

  /**
   * Gets the list element at a particular index.
   *
   * @param index The index to get the list value at
   *
   * @return The list value at the provided index
   *
   * @throws ArrayIndexOutOfBoundsException If the provided index is
   * outside the bounds of the list <code>[0, size())</code>
   */
  public Object get(int index)
  {
    return elements.get(index);
  }

  /**
   * Sets the list element at a particular index.
   *
   * @param index The list index at which to set a value 
   * @param element The value to set at the specified index
   *
   * @return The value previously held at the specified index
   *
   * @throws ArrayIndexOutOfBoundsException If the provided index is
   * outside the bounds of the list <code>[0, size())</code>
   */
  public Object set(int index, Object element)
  {
    Object result;
    result = elements.set(index, element);
    fireContentsChanged(this, index, index);
    return result;
  }

  /**
   * Inserts an element at a particular index in the list. Each element at
   * index <code>i >= index</code> is shifted to position <code>i+1</code>.
   * If <code>index</code> is equal to <code>size()</code>, this is
   * equivalent to appending an element to the array. Any
   * <code>index</code> greater than <code>size()</code> is illegal.
   *
   * @param index The index to insert the element at
   * @param element The element to insert at the index
   *
   * @throws ArrayIndexOutOfBoundsException If the provided index is
   * outside the bounds <code>[0, size()]</code>
   */
  public void add(int index, Object element)
  {
    elements.add(index, element);
    fireIntervalAdded(this, index, index);
  }

  /**
   * Inserts an element at the end of the list. This is equivalent to
   * calling <code>list.add(list.size(), element)</code>.
   *
   * @param element The element to add to the list
   */
  public void addElement(Object element)
  {
    int s = elements.size();
    elements.add(element);
    fireIntervalAdded(this, s, s);
  }

  /**
   * Gets the number of elements in the list.
   *
   * @return The number of elements in the list
   */
  public int size()
  {
    return elements.size();
  }

  /**
   * Gets an array containing the elements of the list.
   *
   * @return An array of the objects in the list, in the order they occur
   * in the list
   */
  public Object[] toArray()
  {
    return elements.toArray();
  }

  /**
   * Determines whether a particular element is a member of the list.
   *
   * @param element The element to search for
   *
   * @return <code>true</code> if <code>element</code> is a member of the
   * list, otherwise <code>false</code>
   */
  public boolean contains(Object element)
  {
    return elements.contains(element);
  }

  /**
   * Copies the list into a provided array. The provided array must be at
   * least as large as the list.
   *
   * @param array The array to copy the list into
   * 
   * @throws IndexOutOfBoundsException if the array is too small to hold the
   * elements of the list
   */
  public void copyInto(Object[] array)
  {
    elements.copyInto(array);
  }

  /**
   * Erases all the elements of the list, setting the list's size to 0.
   */
  public void clear()
  {
    int s = elements.size();
    if (s > 0)
    {
      elements.clear();
      fireIntervalRemoved(this, 0, s - 1);
    }
  }

  /**
   * Removes the element at a particular index from the list.
   *
   * @param index The index of the element to remove
   *
   * @return The value at the index, which has been removed from the list
   *
   * @throws ArrayIndexOutOfBoundsException If the provided index is
   * outside the bounds of the list <code>[0, size())</code>
   */
  public Object remove(int index)
  {
    Object result;
    result = elements.remove(index);
    fireIntervalRemoved(this, index, index);
    return result;
  }

  /**
   * Determines whether the list is empty.
   *
   * @return <code>true</code> if the list is empty, otherwise
   * <code>false</code>
   */
  public boolean isEmpty()
  {
    return elements.isEmpty();
  }

  /**
   * Returns an {@link java.util.Enumeration} over the elements of the list.
   *
   * @return A new enumeration which iterates over the list
   */
  public Enumeration elements()
  {
    return elements.elements();
  }

  /**
   * Sets the capacity of the list to be equal to its size. The list's capacity
   * is the number of elements it can hold before it needs to be reallocated.
   * The list's size is the number of elements it currently holds. 
   */
  public void trimToSize()
  {
    elements.trimToSize();
  }

  /**
   * Ensures that the list's capacity is at least equal to
   * <code>size</code>. The list's capacity is the number of elements it
   * can hold before it needs to be reallocated.
   *
   * @param size The capacity to ensure the list can hold
   */
  public void ensureCapacity(int size)
  {
    elements.ensureCapacity(size);
  }

  /**
   * Sets the size of the list to a particular value. If the specified size
   * is greater than the current size, the values at the excess list
   * indices are set to <code>null</code>.  If the specified size is less
   * than the current size, the excess elements are removed from the list.
   *
   * @param size The new size to set the list to
   */
  public void setSize(int size)
  {
    int oldSize = elements.size();
    elements.setSize(size);
    if (oldSize < size) 
    {
      fireIntervalAdded(this, oldSize, size - 1); 
    }
    else if (oldSize > size) 
    {
      this.fireIntervalRemoved(this, size, oldSize - 1);
    }
  }

  /**
   * Gets the capacity of the list. The list's capacity is the number of
   * elements it can hold before it needs to be reallocated. 
   *
   * @return The capacity of the list
   */
  public int capacity()
  {
    return elements.capacity();
  }

  /**
   * Gets the first element in the list.
   *
   * @return The first element in the list
   */
  public Object firstElement()
  {
    return elements.firstElement();
  }

  /**
   * Gets the last element in the list.
   *
   * @return The last element in the list
   */
  public Object lastElement()
  {
    return elements.lastElement();
  }

  /**
   * Sets the list element at a particular index.
   *
   * @param element The value to set at the specified index
   * @param index The list index at which to set a value 
   *
   * @throws ArrayIndexOutOfBoundsException If the provided index is
   * outside the bounds of the list <code>[0, size())</code>
   */
  public void setElementAt(Object element, int index)
  {
    elements.setElementAt(element, index);
    fireContentsChanged(this, index, index);
  }

  /**
   * Removes the element at a particular index from the list.
   *
   * @param index The index of the element to remove
   *
   * @throws ArrayIndexOutOfBoundsException If the provided index is
   * outside the bounds of the list <code>[0, size())</code>
   */
  public void removeElementAt(int index)
  {
    elements.remove(index);
    fireIntervalRemoved(this, index, index);
  }

  /**
   * Inserts an element at a particular index in the list. Each element at
   * index <code>i >= index</code> is shifted to position <code>i+1</code>.
   * If <code>index</code> is equal to <code>size()</code>, this is
   * equivalent to appending an element to the array. Any
   * <code>index</code> greater than <code>size()</code> is illegal.
   *
   * @param element The element to insert at the index
   * @param index The index to insert the element at
   *
   * @throws ArrayIndexOutOfBoundsException If the provided index is
   * outside the bounds <code>[0, size()]</code>
   */
  public void insertElementAt(Object element, int index)
  {
    elements.insertElementAt(element, index);
    fireIntervalAdded(this, index, index);
  }

  /**
   * Removes the first occurrence of a particular element in the list. If the
   * element does not exist in the list, nothing happens.
   *
   * @param element The element to remove
   *
   * @return <code>true</code> if the element existed in the list (and was
   * removed), <code>false</code> otherwise
   */
  public boolean removeElement(Object element)
  {
    int index;
    index = elements.indexOf(element);
    if (index != -1)
      {
        elements.remove(index);
        fireIntervalRemoved(this, index, index);
        return true;
      }
    return false;
  }

  /**
   * Remove all elements in the list.
   */
  public void removeAllElements()
  {
    int size;
    size = size();
    if (size > 0)
      {
        elements.clear();
        fireIntervalRemoved(this, 0, size - 1);
      }
  }

  /**
   * Remove all elements between <code>startIndex</code> and
   * <code>endIndex</code> inclusive.
   *
   * @param startIndex The first index in the range to remove
   * @param endIndex The last index in the range to remove
   *
   * @throws ArrayIndexOutOfBoundsException if either index is outside the
   * valid range of indices for this list <code>[0, size())</code>
   * @throws IllegalArgumentException if <code>startIndex > endIndex</code>
   */
  public void removeRange(int startIndex, int endIndex)
  {
    int index;
    if (startIndex > endIndex)
      throw new IllegalArgumentException();
    for (index = endIndex; index >= startIndex; index--)
      elements.remove(index);
    fireIntervalRemoved(this, startIndex, endIndex);
  }

  /**
   * Gets the size of the list.
   *
   * @return The number of elements currently in the list
   */
  public int getSize()
  {
    return elements.size();
  }

  /**
   * Gets the list element at a particular index.
   *
   * @param index The index to get the list value at
   *
   * @return The list value at the provided index
   *
   * @throws ArrayIndexOutOfBoundsException If the provided index is
   * outside the bounds of the list <code>[0, size())</code>
   */
  public Object getElementAt(int index)
  {
    return elements.get(index);
  }
}