_basetreemap_submapimpl.java

Java的面向对象数据库系统的源代码

/*
 * _BaseTreeSet_SubMap.java
 * $Id: _BaseTreeMap_SubMapImpl.java,v 1.5 2003/11/20 23:18:41 per_nyfelt Exp $
 * This file is based on TreeMap.java from GNU Classpath. Quote:

TreeMap.java -- a class providing a basic Red-Black Tree data structure,
mapping Object --> Object
Copyright (C) 1998, 1999, 2000, 2001, 2002 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
the Free Software Foundation; either version 2, or (at your option)
any later version.

GNU Classpath 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 for more details.

You should have received a copy of the GNU General Public License
along with GNU Classpath; see the file COPYING.  If not, write to the
Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307 USA.

Linking this library statically or dynamically with other modules is
making a combined work based on this library.  Thus, the terms and
conditions of the GNU General Public License cover the whole
combination.

As a special exception, the copyright holders of this library give you
permission to link this library with independent modules to produce an
executable, regardless of the license terms of these independent
modules, and to copy and distribute the resulting executable under
terms of your choice, provided that you also meet, for each linked
independent module, the terms and conditions of the license of that
module.  An independent module is a module which is not derived from
or based on this library.  If you modify this library, you may extend
this exception to your version of the library, but you are not
obligated to do so.  If you do not wish to do so, delete this
exception statement from your version.

 * end quote.
 *
 * This file is licenced under the same conditions as its original (GPL +
 * "special exception").
 */

package org.ozoneDB.collections;

import java.util.Collection;
import java.util.Comparator;
import java.util.Iterator;
import java.util.Map;
import java.util.NoSuchElementException;
import java.util.Set;
import java.util.SortedMap;
import java.util.TreeMap;

/**
 * <p>Do not use this class directly.
 * This should be an inner class; unfortunately ozone does not support those yet.</p>
 * <p>Implementation of {@link #subMap(Object, Object)} and other map
 * ranges. This class provides a view of a portion of the original backing
 * map, and throws {@link IllegalArgumentException} for attempts to
 * access beyond that range.</p>
 *
 * @author Eric Blake <[e-mail]>
 * @author <a href="mailto:ozoneATmekenkampD0Tcom">Leo Mekenkamp (mind the anti-sp@m)</a> (adaptation for ozone)
 */
public class _BaseTreeMap_SubMapImpl extends AbstractOzoneMap implements _BaseTreeMap_SubMap {

    private static final long serialVersionUID = 1L;

    /**
     * underlying BaseTreeMap.
     */
    protected BaseTreeMap owner;

    /**
     * The lower range of this view, inclusive, or nil for unbounded.
     * Package visible for use by nested classes.
     */
    final Object minKey;

    /**
     * The upper range of this view, exclusive, or nil for unbounded.
     * Package visible for use by nested classes.
     */
    final Object maxKey;

    /**
     * The cache for {@link #entrySet()}.
     */
    private OzoneSet entries;

    /**
     * Create a SubMap representing the elements between minKey (inclusive)
     * and maxKey (exclusive). If minKey is nil, SubMap has no lower bound
     * (headMap). If maxKey is nil, the SubMap has no upper bound (tailMap).
     *
     * @param minKey the lower bound
     * @param maxKey the upper bound
     * @throws IllegalArgumentException if minKey &gt; maxKey
     */
    public _BaseTreeMap_SubMapImpl(BaseTreeMap owner, Object minKey, Object maxKey) {
        this.owner = owner;
        if ((minKey instanceof BaseTreeMap.Node) && (maxKey instanceof BaseTreeMap.Node) &&
                !((BaseTreeMap.Node) minKey).isNil() && !((BaseTreeMap.Node) maxKey).isNil() &&
                owner._org_ozoneDB_compare(minKey, maxKey) > 0)
            throw new IllegalArgumentException("fromKey > toKey");
        this.minKey = minKey;
        this.maxKey = maxKey;
    }

    /**
     * Check if "key" is in within the range bounds for this SubMap. The
     * lower ("from") SubMap range is inclusive, and the upper ("to") bound
     * is exclusive. Package visible for use by nested classes.
     *
     * @param key the key to check
     * @return true if the key is in range
     */
    public final boolean keyInRange(Object key) {
        return (((minKey instanceof BaseTreeMap.Node && ((BaseTreeMap.Node) minKey).isNil()) || owner._org_ozoneDB_compare(key, minKey) >= 0)
        && ((maxKey instanceof BaseTreeMap.Node && ((BaseTreeMap.Node) maxKey).isNil()) || owner._org_ozoneDB_compare(key, maxKey) < 0));
    }

    public void clear() {
        BaseTreeMap.Node next = owner._org_ozoneDB_lowestGreaterThan(minKey, true);
        BaseTreeMap.Node max = owner._org_ozoneDB_lowestGreaterThan(maxKey, false);
        while (!next.equals(max)) {
            BaseTreeMap.Node current = next;
            next = owner._org_ozoneDB_successor(current);
            owner._org_ozoneDB_removeNode(current);
        }
    }

    public Comparator comparator() {
        return owner.comparator();
    }

    public boolean containsKey(Object key) {
        return keyInRange(key) && owner.containsKey(key);
    }

    public boolean containsValue(Object value) {
        BaseTreeMap.Node node = owner._org_ozoneDB_lowestGreaterThan(minKey, true);
        BaseTreeMap.Node max = owner._org_ozoneDB_lowestGreaterThan(maxKey, false);
        while (node != max) {
            if (equals(value, node.getValue()))
                return true;
            node = owner._org_ozoneDB_successor(node);
        }
        return false;
    }

    public Set entrySet() {
        if (entries == null) {
// TODO: when FakeFactoryGenerator is finished replace with
//            entries = BaseTreeMap_SubMap_entrySetFactory.getDefault.create(self());
            entries = (OzoneSet) database().createObject(
                    _BaseTreeMap_SubMap_entrySet.class,
                    new Class[] {_BaseTreeMap_SubMap.class},
                    new Object[] {self()});
        }
        return entries;
    }

    public Object firstKey() {
        BaseTreeMap.Node node = owner._org_ozoneDB_lowestGreaterThan(minKey, true);
        if (node.isNil() || ! keyInRange(node.getKey()))
            throw new NoSuchElementException();
        return node.getKey();
    }

    public Object get(Object key) {
        if (keyInRange(key))
            return owner.get(key);
        return null;
    }

    public SortedMap headMap(Object toKey) {
        if (! keyInRange(toKey))
            throw new IllegalArgumentException("key outside range");
// TODO: replace when FakeFactoryGenerator is ready
//        BaseTreeMapImpl_SubMapFactory.getDefault.create(owner, minKey, toKey);
        return (SortedMap) database().createObject(
                _BaseTreeMap_SubMap.class,
                new Class[] {BaseTreeMap.class, Object.class, Object.class},
                new Object[] {owner, minKey, toKey}
        );
    }

    public Set keySet() {
        if (keys == null) {
// TODO: replace when FakeFactoryGenerator is ready
//        BaseTreeMapImpl_SubMapFactory.getDefault.create(owner, minKey, toKey);
            keys = (Set) database().createObject(
                    _BaseTreeMap_SubMap_keySet.class,
                    new Class[] {_BaseTreeMap_SubMap.class},
                    new Object[] {self()}
            );
        }
        return keys;
    }

    public Object lastKey() {
        BaseTreeMap.Node node = owner._org_ozoneDB_highestLessThan(maxKey);
        if (node.isNil() || ! keyInRange(node.getKey()))
            throw new NoSuchElementException();
        return node.getKey();
    }

    public Object put(Object key, Object value) {
        if (! keyInRange(key))
            throw new IllegalArgumentException("Key outside range");
        return owner.put(key, value);
    }

    public Object remove(Object key) {
        if (keyInRange(key))
            return owner.remove(key);
        return null;
    }

    public int size() {
        BaseTreeMap.Node node = owner._org_ozoneDB_lowestGreaterThan(minKey, true);
        BaseTreeMap.Node max = owner._org_ozoneDB_lowestGreaterThan(maxKey, false);
        int count = 0;
        while (!node.equals(max)) {
            count++;
            node = owner._org_ozoneDB_successor(node);
        }
        return count;
    }

    public SortedMap subMap(Object fromKey, Object toKey) {
        if (! keyInRange(fromKey) || ! keyInRange(toKey))
            throw new IllegalArgumentException("key outside range");
// TODO: replace when FakeFactoryGenerator is ready
//        BaseTreeMapImpl_SubMapFactory.getDefault.create(owner, fromKey, toKey);
        return (SortedMap) database().createObject(
                _BaseTreeMap_SubMap.class,
                new Class[] {BaseTreeMap.class, Object.class, Object.class},
                new Object[] {owner, fromKey, toKey}
        );
    }

    public SortedMap tailMap(Object fromKey) {
        if (! keyInRange(fromKey))
            throw new IllegalArgumentException("key outside range");
// TODO: replace when FakeFactoryGenerator is ready
//        BaseTreeMapImpl_SubMapFactory.getDefault.create(owner, fromKey, maxKey);
        return (SortedMap) database().createObject(
                _BaseTreeMap_SubMap.class,
                new Class[] {BaseTreeMap.class, Object.class, Object.class},
                new Object[] {owner, fromKey, maxKey}
        );
    }

    public Collection values() {
        if (values == null) {
// TODO: replace when FakeFactoryGenerator is ready
//        BaseTreeMapImpl_SubMapFactory.getDefault.create(owner, minKey, toKey);
            values = (OzoneCollection) database().createObject(
                    _BaseTreeMap_SubMap_values.class,
                    new Class[] {_BaseTreeMap_SubMap.class},
                    new Object[] {self()}
            );
        }
        return values;
    }

    /** <p>Returns a <code>Map</code> that contains the same entries as this
     * persistent one; it is (by nature of the client-server enviromnent) always
     * a 'deep' copy of this <code>OzoneMap</code>. I.e. the contents of
     * this <code>OzoneMap</code> instance are always copied to the client
     * by use of serialization.</p>
     *
     */
    public Map getClientMap() {
        return getClientSortedMap();
    }

    /** <p>Returns a <code>SortedMap</code> that contains the same entries as this
     * persistent one; it is (by nature of the client-server enviromnent) always
     * a 'deep' copy of this <code>OzoneSortedMap</code>. I.e. the contents of
     * this <code>OzoneSortedMap</code> instance are always copied to the client
     * by use of serialization.</p>
     *
     */
    public SortedMap getClientSortedMap() {
        TreeMap result = comparator() == null ? new TreeMap() : new TreeMap(comparator());
        for (Iterator i = ((OzoneSet) entrySet())._org_ozoneDB_internalIterator(); i.hasNext(); ) {
            Map.Entry entry = (Map.Entry) i.next();
            result.put(entry.getKey(), entry.getValue());
        }
        return result;
    }

    public Object getMinKey() {
        return minKey;
    }

    public Object getMaxKey() {
        return maxKey;
    }

    public BaseTreeMap getOwner() {
        return owner;
    }

    /** <p>Basically nothing more than a typecasted <code>HeadMap</code> method.
     * Because subsets are also <code>OzoneSortedMap</code>s, this method is
     * provided to do away with the need for a typecast.</p>
     *
     */
    public OzoneSortedMap ozoneHeadMap(Object toKey) {
        return (OzoneSortedMap) headMap(toKey);
    }

    /** <p>Basically nothing more than a typecasted <code>SubMap</code> method.
     * Because subsets are also <code>OzoneSortedMap</code>s, this method is
     * provided to do away with the need for a typecast.</p>
     *
     */
    public OzoneSortedMap ozoneSubMap(Object fromKey, Object toKey) {
        return (OzoneSortedMap) subMap(fromKey, toKey);
    }

    /** <p>Basically nothing more than a typecasted <code>TailMap</code> method.</p>
     * Because subsets are also <code>OzoneSortedMap</code>s, this method is
     * provided to do away with the need for a typecast.</p>
     *
     */
    public OzoneSortedMap ozoneTailMap(Object toKey) {
        return (OzoneSortedMap) tailMap(toKey);
    }

}