Java example source code file (DefaultListModel.java)

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abstractlistmodel, defaultlistmodel, enumeration, event, gui, illegalargumentexception, object, string, swing, util, vector

The DefaultListModel.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;

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

import javax.swing.event.*;


/**
 * This class loosely implements the <code>java.util.Vector
 * API, in that it implements the 1.1.x version of
 * <code>java.util.Vector, has no collection class support,
 * and notifies the <code>ListDataListeners when changes occur.
 * Presently it delegates to a <code>Vector,
 * in a future release it will be a real Collection implementation.
 * <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}.
 *
 * @param <E> the type of the elements of this model
 *
 * @author Hans Muller
 */
public class DefaultListModel<E> extends AbstractListModel
{
    private Vector<E> delegate = new Vector();

    /**
     * Returns the number of components in this list.
     * <p>
     * This method is identical to <code>size, which implements the
     * <code>List interface defined in the 1.2 Collections framework.
     * This method exists in conjunction with <code>setSize so that
     * <code>size is identifiable as a JavaBean property.
     *
     * @return  the number of components in this list
     * @see #size()
     */
    public int getSize() {
        return delegate.size();
    }

    /**
     * Returns the component at the specified index.
     * <blockquote>
     * <b>Note: Although this method is not deprecated, the preferred
     *    method to use is <code>get(int), which implements the
     *    <code>List interface defined in the 1.2 Collections framework.
     * </blockquote>
     * @param      index   an index into this list
     * @return     the component at the specified index
     * @exception  ArrayIndexOutOfBoundsException  if the <code>index
     *             is negative or greater than the current size of this
     *             list
     * @see #get(int)
     */
    public E getElementAt(int index) {
        return delegate.elementAt(index);
    }

    /**
     * Copies the components of this list into the specified array.
     * The array must be big enough to hold all the objects in this list,
     * else an <code>IndexOutOfBoundsException is thrown.
     *
     * @param   anArray   the array into which the components get copied
     * @see Vector#copyInto(Object[])
     */
    public void copyInto(Object anArray[]) {
        delegate.copyInto(anArray);
    }

    /**
     * Trims the capacity of this list to be the list's current size.
     *
     * @see Vector#trimToSize()
     */
    public void trimToSize() {
        delegate.trimToSize();
    }

    /**
     * Increases the capacity of this list, if necessary, to ensure
     * that it can hold at least the number of components specified by
     * the minimum capacity argument.
     *
     * @param   minCapacity   the desired minimum capacity
     * @see Vector#ensureCapacity(int)
     */
    public void ensureCapacity(int minCapacity) {
        delegate.ensureCapacity(minCapacity);
    }

    /**
     * Sets the size of this list.
     *
     * @param   newSize   the new size of this list
     * @see Vector#setSize(int)
     */
    public void setSize(int newSize) {
        int oldSize = delegate.size();
        delegate.setSize(newSize);
        if (oldSize > newSize) {
            fireIntervalRemoved(this, newSize, oldSize-1);
        }
        else if (oldSize < newSize) {
            fireIntervalAdded(this, oldSize, newSize-1);
        }
    }

    /**
     * Returns the current capacity of this list.
     *
     * @return  the current capacity
     * @see Vector#capacity()
     */
    public int capacity() {
        return delegate.capacity();
    }

    /**
     * Returns the number of components in this list.
     *
     * @return  the number of components in this list
     * @see Vector#size()
     */
    public int size() {
        return delegate.size();
    }

    /**
     * Tests whether this list has any components.
     *
     * @return  <code>true if and only if this list has
     *          no components, that is, its size is zero;
     *          <code>false otherwise
     * @see Vector#isEmpty()
     */
    public boolean isEmpty() {
        return delegate.isEmpty();
    }

    /**
     * Returns an enumeration of the components of this list.
     *
     * @return  an enumeration of the components of this list
     * @see Vector#elements()
     */
    public Enumeration<E> elements() {
        return delegate.elements();
    }

    /**
     * Tests whether the specified object is a component in this list.
     *
     * @param   elem   an object
     * @return  <code>true if the specified object
     *          is the same as a component in this list
     * @see Vector#contains(Object)
     */
    public boolean contains(Object elem) {
        return delegate.contains(elem);
    }

    /**
     * Searches for the first occurrence of <code>elem.
     *
     * @param   elem   an object
     * @return  the index of the first occurrence of the argument in this
     *          list; returns <code>-1 if the object is not found
     * @see Vector#indexOf(Object)
     */
    public int indexOf(Object elem) {
        return delegate.indexOf(elem);
    }

    /**
     * Searches for the first occurrence of <code>elem, beginning
     * the search at <code>index.
     *
     * @param   elem    an desired component
     * @param   index   the index from which to begin searching
     * @return  the index where the first occurrence of <code>elem
     *          is found after <code>index; returns -1
     *          if the <code>elem is not found in the list
     * @see Vector#indexOf(Object,int)
     */
     public int indexOf(Object elem, int index) {
        return delegate.indexOf(elem, index);
    }

    /**
     * Returns the index of the last occurrence of <code>elem.
     *
     * @param   elem   the desired component
     * @return  the index of the last occurrence of <code>elem
     *          in the list; returns <code>-1 if the object is not found
     * @see Vector#lastIndexOf(Object)
     */
    public int lastIndexOf(Object elem) {
        return delegate.lastIndexOf(elem);
    }

    /**
     * Searches backwards for <code>elem, starting from the
     * specified index, and returns an index to it.
     *
     * @param  elem    the desired component
     * @param  index   the index to start searching from
     * @return the index of the last occurrence of the <code>elem
     *          in this list at position less than <code>index;
     *          returns <code>-1 if the object is not found
     * @see Vector#lastIndexOf(Object,int)
     */
    public int lastIndexOf(Object elem, int index) {
        return delegate.lastIndexOf(elem, index);
    }

    /**
     * Returns the component at the specified index.
     * Throws an <code>ArrayIndexOutOfBoundsException if the index
     * is negative or not less than the size of the list.
     * <blockquote>
     * <b>Note: Although this method is not deprecated, the preferred
     *    method to use is <code>get(int), which implements the
     *    <code>List interface defined in the 1.2 Collections framework.
     * </blockquote>
     *
     * @param      index   an index into this list
     * @return     the component at the specified index
     * @see #get(int)
     * @see Vector#elementAt(int)
     */
    public E elementAt(int index) {
        return delegate.elementAt(index);
    }

    /**
     * Returns the first component of this list.
     * Throws a <code>NoSuchElementException if this
     * vector has no components.
     * @return     the first component of this list
     * @see Vector#firstElement()
     */
    public E firstElement() {
        return delegate.firstElement();
    }

    /**
     * Returns the last component of the list.
     * Throws a <code>NoSuchElementException if this vector
     * has no components.
     *
     * @return  the last component of the list
     * @see Vector#lastElement()
     */
    public E lastElement() {
        return delegate.lastElement();
    }

    /**
     * Sets the component at the specified <code>index of this
     * list to be the specified element. The previous component at that
     * position is discarded.
     * <p>
     * Throws an <code>ArrayIndexOutOfBoundsException if the index
     * is invalid.
     * <blockquote>
     * <b>Note: Although this method is not deprecated, the preferred
     *    method to use is <code>set(int,Object), which implements the
     *    <code>List interface defined in the 1.2 Collections framework.
     * </blockquote>
     *
     * @param      element what the component is to be set to
     * @param      index   the specified index
     * @see #set(int,Object)
     * @see Vector#setElementAt(Object,int)
     */
    public void setElementAt(E element, int index) {
        delegate.setElementAt(element, index);
        fireContentsChanged(this, index, index);
    }

    /**
     * Deletes the component at the specified index.
     * <p>
     * Throws an <code>ArrayIndexOutOfBoundsException if the index
     * is invalid.
     * <blockquote>
     * <b>Note: Although this method is not deprecated, the preferred
     *    method to use is <code>remove(int), which implements the
     *    <code>List interface defined in the 1.2 Collections framework.
     * </blockquote>
     *
     * @param      index   the index of the object to remove
     * @see #remove(int)
     * @see Vector#removeElementAt(int)
     */
    public void removeElementAt(int index) {
        delegate.removeElementAt(index);
        fireIntervalRemoved(this, index, index);
    }

    /**
     * Inserts the specified element as a component in this list at the
     * specified <code>index.
     * <p>
     * Throws an <code>ArrayIndexOutOfBoundsException if the index
     * is invalid.
     * <blockquote>
     * <b>Note: Although this method is not deprecated, the preferred
     *    method to use is <code>add(int,Object), which implements the
     *    <code>List interface defined in the 1.2 Collections framework.
     * </blockquote>
     *
     * @param      element the component to insert
     * @param      index   where to insert the new component
     * @exception  ArrayIndexOutOfBoundsException  if the index was invalid
     * @see #add(int,Object)
     * @see Vector#insertElementAt(Object,int)
     */
    public void insertElementAt(E element, int index) {
        delegate.insertElementAt(element, index);
        fireIntervalAdded(this, index, index);
    }

    /**
     * Adds the specified component to the end of this list.
     *
     * @param   element   the component to be added
     * @see Vector#addElement(Object)
     */
    public void addElement(E element) {
        int index = delegate.size();
        delegate.addElement(element);
        fireIntervalAdded(this, index, index);
    }

    /**
     * Removes the first (lowest-indexed) occurrence of the argument
     * from this list.
     *
     * @param   obj   the component to be removed
     * @return  <code>true if the argument was a component of this
     *          list; <code>false otherwise
     * @see Vector#removeElement(Object)
     */
    public boolean removeElement(Object obj) {
        int index = indexOf(obj);
        boolean rv = delegate.removeElement(obj);
        if (index >= 0) {
            fireIntervalRemoved(this, index, index);
        }
        return rv;
    }


    /**
     * Removes all components from this list and sets its size to zero.
     * <blockquote>
     * <b>Note: Although this method is not deprecated, the preferred
     *    method to use is <code>clear, which implements the
     *    <code>List interface defined in the 1.2 Collections framework.
     * </blockquote>
     *
     * @see #clear()
     * @see Vector#removeAllElements()
     */
    public void removeAllElements() {
        int index1 = delegate.size()-1;
        delegate.removeAllElements();
        if (index1 >= 0) {
            fireIntervalRemoved(this, 0, index1);
        }
    }


    /**
     * Returns a string that displays and identifies this
     * object's properties.
     *
     * @return a String representation of this object
     */
   public String toString() {
        return delegate.toString();
    }


    /* The remaining methods are included for compatibility with the
     * Java 2 platform Vector class.
     */

    /**
     * Returns an array containing all of the elements in this list in the
     * correct order.
     *
     * @return an array containing the elements of the list
     * @see Vector#toArray()
     */
    public Object[] toArray() {
        Object[] rv = new Object[delegate.size()];
        delegate.copyInto(rv);
        return rv;
    }

    /**
     * Returns the element at the specified position in this list.
     * <p>
     * Throws an <code>ArrayIndexOutOfBoundsException
     * if the index is out of range
     * (<code>index < 0 || index >= size()).
     *
     * @param index index of element to return
     */
    public E get(int index) {
        return delegate.elementAt(index);
    }

    /**
     * Replaces the element at the specified position in this list with the
     * specified element.
     * <p>
     * Throws an <code>ArrayIndexOutOfBoundsException
     * if the index is out of range
     * (<code>index < 0 || index >= size()).
     *
     * @param index index of element to replace
     * @param element element to be stored at the specified position
     * @return the element previously at the specified position
     */
    public E set(int index, E element) {
        E rv = delegate.elementAt(index);
        delegate.setElementAt(element, index);
        fireContentsChanged(this, index, index);
        return rv;
    }

    /**
     * Inserts the specified element at the specified position in this list.
     * <p>
     * Throws an <code>ArrayIndexOutOfBoundsException if the
     * index is out of range
     * (<code>index < 0 || index > size()).
     *
     * @param index index at which the specified element is to be inserted
     * @param element element to be inserted
     */
    public void add(int index, E element) {
        delegate.insertElementAt(element, index);
        fireIntervalAdded(this, index, index);
    }

    /**
     * Removes the element at the specified position in this list.
     * Returns the element that was removed from the list.
     * <p>
     * Throws an <code>ArrayIndexOutOfBoundsException
     * if the index is out of range
     * (<code>index < 0 || index >= size()).
     *
     * @param index the index of the element to removed
     * @return the element previously at the specified position
     */
    public E remove(int index) {
        E rv = delegate.elementAt(index);
        delegate.removeElementAt(index);
        fireIntervalRemoved(this, index, index);
        return rv;
    }

    /**
     * Removes all of the elements from this list.  The list will
     * be empty after this call returns (unless it throws an exception).
     */
    public void clear() {
        int index1 = delegate.size()-1;
        delegate.removeAllElements();
        if (index1 >= 0) {
            fireIntervalRemoved(this, 0, index1);
        }
    }

    /**
     * Deletes the components at the specified range of indexes.
     * The removal is inclusive, so specifying a range of (1,5)
     * removes the component at index 1 and the component at index 5,
     * as well as all components in between.
     * <p>
     * Throws an <code>ArrayIndexOutOfBoundsException
     * if the index was invalid.
     * Throws an <code>IllegalArgumentException if
     * <code>fromIndex > toIndex.
     *
     * @param      fromIndex the index of the lower end of the range
     * @param      toIndex   the index of the upper end of the range
     * @see        #remove(int)
     */
    public void removeRange(int fromIndex, int toIndex) {
        if (fromIndex > toIndex) {
            throw new IllegalArgumentException("fromIndex must be <= toIndex");
        }
        for(int i = toIndex; i >= fromIndex; i--) {
            delegate.removeElementAt(i);
        }
        fireIntervalRemoved(this, fromIndex, toIndex);
    }

    /*
    public void addAll(Collection c) {
    }

    public void addAll(int index, Collection c) {
    }
    */
}