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/*
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 * of the Common Development and Distribution License 
 * (the "License").  You may not use this file except 
 * in compliance with the License.
 * 
 * You can obtain a copy of the license at 
 * glassfish/bootstrap/legal/CDDLv1.0.txt or 
 * https://glassfish.dev.java.net/public/CDDLv1.0.html. 
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 * 
 * When distributing Covered Code, include this CDDL 
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 * glassfish/bootstrap/legal/CDDLv1.0.txt.  If applicable, 
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// Copyright (c) 1998, 2005, Oracle. All rights reserved.  
package oracle.toplink.essentials.indirection;

import java.util.*;

/**
 * IndirectMap allows a domain class to take advantage of TopLink indirection
 * without having to declare its instance variable as a ValueHolderInterface.
 * 

To use an IndirectMap:

    *
  • Declare the appropriate instance variable with type Hashtable (jdk1.1) * or Map (jdk1.2). *
  • Send the message #useTransparentMap(String) to the appropriate * CollectionMapping. *
* TopLink will place an * IndirectMap in the instance variable when the containing domain object is read from * the datatabase. With the first message sent to the IndirectMap, the contents * are fetched from the database and normal Hashtable/Map behavior is resumed. * * @see oracle.toplink.essentials.mappings.CollectionMapping * @see oracle.toplink.essentials.indirection.IndirectList * @author Big Country * @since TOPLink/Java 2.5 */ public class IndirectMap extends Hashtable implements IndirectContainer { /** Reduce type casting */ protected Hashtable delegate; /** Delegate indirection behavior to a value holder */ protected ValueHolderInterface valueHolder; /** The mapping attribute name, used to raise change events. */ private transient String attributeName; /** Store initial size for lazy init. */ protected int initialCapacity = 11; /** Store load factor for lazy init. */ protected float loadFactor = 0.75f; /** * PUBLIC: * Construct a new, empty IndirectMap with a default * capacity and load factor. */ public IndirectMap() { this(11); } /** * PUBLIC: * Construct a new, empty IndirectMap with the specified initial capacity * and default load factor. * * @param initialCapacity the initial capacity of the hashtable */ public IndirectMap(int initialCapacity) { this(initialCapacity, 0.75f); } /** * PUBLIC: * Construct a new, empty IndirectMap with the specified initial * capacity and load factor. * * @param initialCapacity the initial capacity of the hashtable * @param loadFactor a number between 0.0 and 1.0 * @exception IllegalArgumentException if the initial capacity is less * than or equal to zero, or if the load factor is less than * or equal to zero */ public IndirectMap(int initialCapacity, float loadFactor) { super(0); this.initialize(initialCapacity, loadFactor); } /** * PUBLIC: * Construct a new IndirectMap with the same mappings as the given Map. * The IndirectMap is created with a capacity of twice the number of entries * in the given Map or 11 (whichever is greater), and a default load factor, which is 0.75. * @param m a map containing the mappings to use */ public IndirectMap(Map m) { super(0); this.initialize(m); } /** * Return the freshly-built delegate. */ protected Hashtable buildDelegate() { return (Hashtable)getValueHolder().getValue(); } /** * @see java.util.Hashtable#clear() */ public synchronized void clear() { this.getDelegate().clear(); } /** * @see java.util.Hashtable#clone() * This will result in a database query if necessary. */ /* There are 3 situations when clone() is called: 1. The developer actually wants to clone the collection (typically to modify one of the 2 resulting collections). In which case the contents must be read from the database. 2. A UnitOfWork needs a clone (or backup clone) of the collection. But the UnitOfWork checks "instantiation" before cloning collections ("un-instantiated" collections are not cloned). 3. A MergeManager needs an extra copy of the collection (because the "backup" and "target" are the same object?). But the MergeManager checks "instantiation" before merging collections (again, "un-instantiated" collections are not merged). */ public synchronized Object clone() { IndirectMap result = (IndirectMap)super.clone(); result.delegate = (Hashtable)this.getDelegate().clone(); return result; } /** * @see java.util.Hashtable#contains(java.lang.Object) */ public synchronized boolean contains(Object value) { return this.getDelegate().contains(value); } /** * @see java.util.Hashtable#containsKey(java.lang.Object) */ public synchronized boolean containsKey(Object key) { return this.getDelegate().containsKey(key); } /** * @see java.util.Hashtable#containsValue(java.lang.Object) */ public boolean containsValue(Object value) { return this.getDelegate().containsValue(value); } /** * @see java.util.Hashtable#elements() */ public synchronized Enumeration elements() { return this.getDelegate().elements(); } /** * @see java.util.Hashtable#entrySet() */ public Set entrySet() { return new Set (){ Set delegateSet = IndirectMap.this.getDelegate().entrySet(); public int size(){ return this.delegateSet.size(); } public boolean isEmpty(){ return this.delegateSet.isEmpty(); } public boolean contains(Object o){ return this.delegateSet.contains(o); } public Iterator iterator(){ return new Iterator() { Iterator delegateIterator = delegateSet.iterator(); Object currentObject; public boolean hasNext() { return this.delegateIterator.hasNext(); } public Object next() { this.currentObject = this.delegateIterator.next(); return this.currentObject; } public void remove() { raiseRemoveChangeEvent(((Map.Entry)currentObject).getKey(), ((Map.Entry)currentObject).getValue()); this.delegateIterator.remove(); } }; } public Object[] toArray(){ return this.delegateSet.toArray(); } public Object[] toArray(Object a[]){ return this.delegateSet.toArray(a); } public boolean add(Object o){ return this.delegateSet.add(o); } public boolean remove(Object o){ if (!(o instanceof Map.Entry)) { return false; } return (IndirectMap.this.remove(((Map.Entry)o).getKey()) != null); } public boolean containsAll(Collection c){ return this.delegateSet.containsAll(c); } public boolean addAll(Collection c){ return this.delegateSet.addAll(c); } public boolean retainAll(Collection c){ boolean result = false; Iterator objects = delegateSet.iterator(); while (objects.hasNext()) { Map.Entry object = (Map.Entry)objects.next(); if (!c.contains(object)) { objects.remove(); raiseRemoveChangeEvent(object.getKey(), object.getValue()); result = true; } } return result; } public boolean removeAll(Collection c){ boolean result = false; for (Iterator cs = c.iterator(); cs.hasNext(); ){ Object object = cs.next(); if ( ! (object instanceof Map.Entry)){ continue; } Object removed = IndirectMap.this.remove(((Map.Entry)object).getKey()); if (removed != null){ result = true; } } return result; } public void clear(){ IndirectMap.this.clear(); } public boolean equals(Object o){ return this.delegateSet.equals(o); } public int hashCode(){ return this.delegateSet.hashCode(); } }; } /** * @see java.util.Hashtable#equals(java.lang.Object) */ public synchronized boolean equals(Object o) { return this.getDelegate().equals(o); } /** * @see java.util.Hashtable#get(java.lang.Object) */ public synchronized Object get(Object key) { return this.getDelegate().get(key); } /** * Check whether the contents have been read from the database. * If they have not, read them and set the delegate. */ protected synchronized Hashtable getDelegate() { if (delegate == null) { delegate = this.buildDelegate(); } return delegate; } /** * Return the mapping attribute name, used to raise change events. */ public String getTopLinkAttributeName() { return attributeName; } /** * PUBLIC: * Return the valueHolder. */ public synchronized ValueHolderInterface getValueHolder() { // PERF: lazy initialize value holder and vector as are normally set after creation. if (valueHolder == null) { valueHolder = new ValueHolder(new Hashtable(initialCapacity, loadFactor)); } return valueHolder; } /** * @see java.util.Hashtable#hashCode() */ public synchronized int hashCode() { return this.getDelegate().hashCode(); } /** * Initialize the instance. */ protected void initialize(int initialCapacity, float loadFactor) { this.delegate = null; this.loadFactor = loadFactor; this.initialCapacity = initialCapacity; this.valueHolder = null; } /** * Initialize the instance. */ protected void initialize(Map m) { this.delegate = null; Hashtable temp = new Hashtable(m); this.valueHolder = new ValueHolder(temp); } /** * @see java.util.Hashtable#isEmpty() */ public boolean isEmpty() { return this.getDelegate().isEmpty(); } /** * PUBLIC: * Return whether the contents have been read from the database. */ public boolean isInstantiated() { return this.getValueHolder().isInstantiated(); } /** * @see java.util.Hashtable#keys() */ public synchronized Enumeration keys() { return this.getDelegate().keys(); } /** * @see java.util.Hashtable#keySet() */ public Set keySet() { return new Set (){ Set delegateSet = IndirectMap.this.getDelegate().keySet(); public int size(){ return this.delegateSet.size(); } public boolean isEmpty(){ return this.delegateSet.isEmpty(); } public boolean contains(Object o){ return this.delegateSet.contains(o); } public Iterator iterator(){ return new Iterator() { Iterator delegateIterator = delegateSet.iterator(); Object currentObject; public boolean hasNext() { return this.delegateIterator.hasNext(); } public Object next() { this.currentObject = this.delegateIterator.next(); return this.currentObject; } public void remove() { IndirectMap.this.raiseRemoveChangeEvent(currentObject, IndirectMap.this.getDelegate().get(currentObject)); this.delegateIterator.remove(); } }; } public Object[] toArray(){ return this.delegateSet.toArray(); } public Object[] toArray(Object a[]){ return this.delegateSet.toArray(a); } public boolean add(Object o){ return this.delegateSet.add(o); } public boolean remove(Object o){ return (IndirectMap.this.remove(o) != null); } public boolean containsAll(Collection c){ return this.delegateSet.containsAll(c); } public boolean addAll(Collection c){ return this.delegateSet.addAll(c); } public boolean retainAll(Collection c){ boolean result = false; Iterator objects = delegateSet.iterator(); while (objects.hasNext()) { Object object = objects.next(); if (!c.contains(object)) { objects.remove(); IndirectMap.this.raiseRemoveChangeEvent(object, IndirectMap.this.getDelegate().get(object)); result = true; } } return result; } public boolean removeAll(Collection c){ boolean result = false; for (Iterator cs = c.iterator(); cs.hasNext(); ){ if (IndirectMap.this.remove(cs.next()) != null ) { result = true; } } return result; } public void clear(){ IndirectMap.this.clear(); } public boolean equals(Object o){ return this.delegateSet.equals(o); } public int hashCode(){ return this.delegateSet.hashCode(); } }; } /** * @see java.util.Hashtable#put(java.lang.Object, java.lang.Object) */ public synchronized Object put(Object key, Object value) { Object oldValue = this.getDelegate().put(key, value); if (oldValue != null){ raiseRemoveChangeEvent(key, oldValue); } raiseAddChangeEvent(key, value); return oldValue; } /** * @see java.util.Hashtable#putAll(java.util.Map) */ public synchronized void putAll(Map t) { this.getDelegate().putAll(t); } /** * @see java.util.Hashtable#rehash() */ protected void rehash() { throw new InternalError("unsupported"); } /** * Raise the add change event and relationship maintainence. */ protected void raiseAddChangeEvent(Object key, Object value) { // this is where relationship maintenance would go } /** * Raise the remove change event. */ protected void raiseRemoveChangeEvent(Object key, Object value) { // this is where relationship maintenance would go } /** * @see java.util.Hashtable#remove(java.lang.Object) */ public synchronized Object remove(Object key) { Object value = this.getDelegate().remove(key); if (value != null){ raiseRemoveChangeEvent(key, value); } return value; } /** * Set the mapping attribute name, used to raise change events. * This is required if the change listener is set. */ public void setTopLinkAttributeName(String attributeName) { this.attributeName = attributeName; } /** * PUBLIC: * Set the value holder. */ public void setValueHolder(ValueHolderInterface valueHolder) { this.delegate = null; this.valueHolder = valueHolder; } /** * @see java.util.Hashtable#size() */ public int size() { return this.getDelegate().size(); } /** * PUBLIC: * Use the Hashtable.toString(); but wrap it with braces to indicate * there is a bit of indirection. * Don't allow this method to trigger a database read. * @see java.util.Hashtable#toString() */ public String toString() { if (ValueHolderInterface.shouldToStringInstantiate) { return this.getDelegate().toString(); } if (this.isInstantiated()) { return "{" + this.getDelegate().toString() + "}"; } else { return "{" + oracle.toplink.essentials.internal.helper.Helper.getShortClassName(this.getClass()) + ": not instantiated}"; } } /** * @see java.util.Hashtable#values() */ public Collection values() { return new Collection() { protected Collection delegateCollection = IndirectMap.this.getDelegate().values(); public int size(){ return delegateCollection.size(); } public boolean isEmpty(){ return delegateCollection.isEmpty(); } public boolean contains(Object o){ return delegateCollection.contains(o); } public Iterator iterator() { return new Iterator() { Iterator delegateIterator = delegateCollection.iterator(); Object currentObject; public boolean hasNext() { return this.delegateIterator.hasNext(); } public Object next() { this.currentObject = this.delegateIterator.next(); return this.currentObject; } public void remove() { Iterator iterator = IndirectMap.this.getDelegate().entrySet().iterator(); while (iterator.hasNext()){ Map.Entry entry = (Map.Entry)iterator.next(); if (entry.getValue().equals(currentObject)){ IndirectMap.this.raiseRemoveChangeEvent(entry.getKey(), entry.getValue()); } } this.delegateIterator.remove(); } }; } public Object[] toArray(){ return this.delegateCollection.toArray(); } public Object[] toArray(Object a[]){ return this.delegateCollection.toArray(a); } public boolean add(Object o){ return this.delegateCollection.add(o); } public boolean remove(Object o){ Iterator iterator = IndirectMap.this.getDelegate().entrySet().iterator(); while (iterator.hasNext()){ Map.Entry entry = (Map.Entry)iterator.next(); if (entry.getValue().equals(o)){ IndirectMap.this.raiseRemoveChangeEvent(entry.getKey(), entry.getValue()); } return true; } return false; } public boolean containsAll(Collection c){ return this.delegateCollection.containsAll(c); } public boolean addAll(Collection c){ return this.delegateCollection.addAll(c); } public boolean removeAll(Collection c){ boolean result = false; for (Iterator iterator = c.iterator(); iterator.hasNext();){ if (remove(iterator.next()) ){ result = true; } } return result; } public boolean retainAll(Collection c){ boolean result = false; for (Iterator iterator = IndirectMap.this.entrySet().iterator(); iterator.hasNext();){ Map.Entry entry = (Map.Entry)iterator.next(); if (! c.contains(entry.getValue()) ) { iterator.remove(); result = true; } } return result; } public void clear(){ IndirectMap.this.clear(); } public boolean equals(Object o){ return this.delegateCollection.equals(o); } public int hashCode(){ return this.delegateCollection.hashCode(); } }; } }




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