/*

 * Copyright 2003-2006 Sun Microsystems, Inc.  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.  Sun designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Sun 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,

 * CA 95054 USA or visit www.sun.com if you need additional information or

 * have any questions.

 */

package javax.swing;

import java.io.IOException;

import java.io.ObjectOutputStream;

import java.io.Serializable;

import java.util.Enumeration;

import java.util.Hashtable;

/*

 * Private storage mechanism for Action key-value pairs.

 * In most cases this will be an array of alternating

 * key-value pairs.  As it grows larger it is scaled

 * up to a Hashtable.

 * <p>

 * This does no synchronization, if you need thread safety synchronize on

 * another object before calling this.

 *

 * @author Georges Saab

 * @author Scott Violet

 */

class ArrayTable implements Cloneable {

    // Our field for storage

    private Object table = null;

    private static final int ARRAY_BOUNDARY = 8;

    /**

     * Writes the passed in ArrayTable to the passed in ObjectOutputStream.

     * The data is saved as an integer indicating how many key/value

     * pairs are being archived, followed by the the key/value pairs. If

     * <code>table</code> is null, 0 will be written to <code>s</code>.

     * <p>

     * This is a convenience method that ActionMap/InputMap and

     * AbstractAction use to avoid having the same code in each class.

     */

    static void writeArrayTable(ObjectOutputStream s, ArrayTable table) throws IOException {

        Object keys[];

        if (table == null || (keys = table.getKeys(null)) == null) {

            s.writeInt(0);

        }

        else {

            // Determine how many keys have Serializable values, when

            // done all non-null values in keys identify the Serializable

            // values.

            int validCount = 0;

            for (int counter = 0; counter < keys.length; counter++) {

                Object key = keys[counter];

                /* include in Serialization when both keys and values are Serializable */

                if (    (key instanceof Serializable

                         && table.get(key) instanceof Serializable)

                             ||

                         /* include these only so that we get the appropriate exception below */

                        (key instanceof ClientPropertyKey

                         && ((ClientPropertyKey)key).getReportValueNotSerializable())) {

                    validCount++;

                } else {

                    keys[counter] = null;

                }

            }

            // Write ou the Serializable key/value pairs.

            s.writeInt(validCount);

            if (validCount > 0) {

                for (int counter = 0; counter < keys.length; counter++) {

                    if (keys[counter] != null) {

                        s.writeObject(keys[counter]);

                        s.writeObject(table.get(keys[counter]));

                        if (--validCount == 0) {

                            break;

                        }

                    }

                }

            }

        }

    }

    /*

     * Put the key-value pair into storage

     */

    public void put(Object key, Object value){

        if (table==null) {

            table = new Object[] {key, value};

        } else {

            int size = size();

            if (size < ARRAY_BOUNDARY) {              // We are an array

                if (containsKey(key)) {

                    Object[] tmp = (Object[])table;

                    for (int i = 0; i<tmp.length-1; i+=2) {

                        if (tmp[i].equals(key)) {

                            tmp[i+1]=value;

                            break;

                        }

                    }

                } else {

                    Object[] array = (Object[])table;

                    int i = array.length;

                    Object[] tmp = new Object[i+2];

                    System.arraycopy(array, 0, tmp, 0, i);

                    tmp[i] = key;

                    tmp[i+1] = value;

                    table = tmp;

                }

            } else {                 // We are a hashtable

                if ((size==ARRAY_BOUNDARY) && isArray()) {

                    grow();

                }

                ((Hashtable)table).put(key, value);

            }

        }

    }

    /*

     * Gets the value for key

     */

    public Object get(Object key) {

        Object value = null;

        if (table !=null) {

            if (isArray()) {

                Object[] array = (Object[])table;

                for (int i = 0; i<array.length-1; i+=2) {

                    if (array[i].equals(key)) {

                        value = array[i+1];

                        break;

                    }

                }

            } else {

                value = ((Hashtable)table).get(key);

            }

        }

        return value;

    }

    /*

     * Returns the number of pairs in storage

     */

    public int size() {

        int size;

        if (table==null)

            return 0;

        if (isArray()) {

            size = ((Object[])table).length/2;

        } else {

            size = ((Hashtable)table).size();

        }

        return size;

    }

    /*

     * Returns true if we have a value for the key

     */

    public boolean containsKey(Object key) {

        boolean contains = false;

        if (table !=null) {

            if (isArray()) {

                Object[] array = (Object[])table;

                for (int i = 0; i<array.length-1; i+=2) {

                    if (array[i].equals(key)) {

                        contains = true;

                        break;

                    }

                }

            } else {

                contains = ((Hashtable)table).containsKey(key);

            }

        }

        return contains;

    }

    /*

     * Removes the key and its value

     * Returns the value for the pair removed

     */

    public Object remove(Object key){

        Object value = null;

        if (key==null) {

            return null;

        }

        if (table !=null) {

            if (isArray()){

                // Is key on the list?

                int index = -1;

                Object[] array = (Object[])table;

                for (int i = array.length-2; i>=0; i-=2) {

                    if (array[i].equals(key)) {

                        index = i;

                        value = array[i+1];

                        break;

                    }

                }

                // If so,  remove it

                if (index != -1) {

                    Object[] tmp = new Object[array.length-2];

                    // Copy the list up to index

                    System.arraycopy(array, 0, tmp, 0, index);

                    // Copy from two past the index, up to

                    // the end of tmp (which is two elements

                    // shorter than the old list)

                    if (index < tmp.length)

                        System.arraycopy(array, index+2, tmp, index,

                                         tmp.length - index);

                    // set the listener array to the new array or null

                    table = (tmp.length == 0) ? null : tmp;

                }

            } else {

                value = ((Hashtable)table).remove(key);

            }

            if (size()==ARRAY_BOUNDARY - 1 && !isArray()) {

                shrink();

            }

        }

        return value;

    }

    /**

     * Removes all the mappings.

     */

    public void clear() {

        table = null;

    }

    /*

     * Returns a clone of the <code>ArrayTable</code>.

     */

    public Object clone() {

        ArrayTable newArrayTable = new ArrayTable();

        if (isArray()) {

            Object[] array = (Object[])table;

            for (int i = 0 ;i < array.length-1 ; i+=2) {

                newArrayTable.put(array[i], array[i+1]);

            }

        } else {

            Hashtable tmp = (Hashtable)table;

            Enumeration keys = tmp.keys();

            while (keys.hasMoreElements()) {

                Object o = keys.nextElement();

                newArrayTable.put(o,tmp.get(o));

            }

        }

        return newArrayTable;

    }

    /**

     * Returns the keys of the table, or <code>null</code> if there

     * are currently no bindings.

     * @param keys  array of keys

     * @return an array of bindings

     */

    public Object[] getKeys(Object[] keys) {

        if (table == null) {

            return null;

        }

        if (isArray()) {

            Object[] array = (Object[])table;

            if (keys == null) {

                keys = new Object[array.length / 2];

            }

            for (int i = 0, index = 0 ;i < array.length-1 ; i+=2,

                     index++) {

                keys[index] = array[i];

            }

        } else {

            Hashtable tmp = (Hashtable)table;

            Enumeration enum_ = tmp.keys();

            int counter = tmp.size();

            if (keys == null) {

                keys = new Object[counter];

            }

            while (counter > 0) {

                keys[--counter] = enum_.nextElement();

            }

        }

        return keys;

    }

    /*

     * Returns true if the current storage mechanism is

     * an array of alternating key-value pairs.

     */

    private boolean isArray(){

        return (table instanceof Object[]);

    }

    /*

     * Grows the storage from an array to a hashtable.

     */

    private void grow() {

        Object[] array = (Object[])table;

        Hashtable tmp = new Hashtable(array.length/2);

        for (int i = 0; i<array.length; i+=2) {

            tmp.put(array[i], array[i+1]);

        }

        table = tmp;

    }

    /*

     * Shrinks the storage from a hashtable to an array.

     */

    private void shrink() {

        Hashtable tmp = (Hashtable)table;

        Object[] array = new Object[tmp.size()*2];

        Enumeration keys = tmp.keys();

        int j = 0;

        while (keys.hasMoreElements()) {

            Object o = keys.nextElement();

            array[j] = o;

            array[j+1] = tmp.get(o);

            j+=2;

        }

        table = array;

    }

}