/* Open Source Java Caching Service
* Copyright (C) 2002 Frank Karlstr�m
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
* The author can be contacted by email: fjankk@users.sourceforge.net
*/
package org.fjank.jcache.collection;
import java.util.Collection;
import java.util.Iterator;
import java.util.Map;
import java.util.Set;
import javax.util.jcache.Attributes;
import javax.util.jcache.CacheException;
import javax.util.jcache.CacheFullException;
import javax.util.jcache.CacheMap;
import javax.util.jcache.NotARetrievableObjectException;
import org.fjank.jcache.CacheAccessImpl2;
import org.fjank.jcache.CacheGroup;
import org.fjank.jcache.CacheObject;
import org.fjank.jcache.CacheRegion;
/**A Map based implementation of CacheAccess.
* @author Frank Karlstr�m
*
*/
public class MapAdapter implements CacheMap {
private final CacheAccessImpl2 acc;
public MapAdapter(CacheAccessImpl2 originalAccess) {
this.acc=originalAccess;
}
/**Returns the current number of objects (Raw objects and groups)
* in this region. this method is not recursive across the groups,
* so any objects under the groups ini the region root is not
* accounted for.
*
* @see java.util.Map#size()
*/
public int size() {
return acc.getRegion().getObjectCount();
}
public boolean isEmpty() {
return acc.getRegion().getObjectCount()==0;
}
/**Returns true if this map contains a mapping for the specified key.
* More formally, returns true if and
* only if this map contains at a mapping for a key k such that
* (key==null ? k==null : key.equals(k)).
* (There can be at most one such mapping.)
* @param key key whose presence in this map is to be tested.
* @return <code>true</code> if this map contains a mapping for the specified key.
* @throws NullPointerException if the key is null.
* @see java.util.Map#containsKey(java.lang.Object)
*/
public boolean containsKey(Object key) {
if(key==null) throw new NullPointerException("This Map does not permit null keys.");
return acc.isPresent(key);
}
public boolean containsValue(Object value) {
CacheRegion region = acc.getRegion();
return region.containsValue(value);
}
/**
* Returns the value to which this map maps the specified key. Returns
* <tt>null</tt> if the map contains no mapping for this key.
*
* <p>More formally, if this map contains a mapping from a key
* <tt>k</tt> to a value <tt>v</tt> such that <tt>(key.equals(k))</tt>,
* then this method returns <tt>v</tt>; otherwise
* it returns <tt>null</tt>. (There can be at most one such mapping.)
*
* @param key key whose associated value is to be returned.
* @return the value to which this map maps the specified key, or
* <tt>null</tt> if the map contains no mapping for this key.
*
* @throws ClassCastException if an attempt is mad to retrieve a group.
* @throws NullPointerException key is <tt>null</tt>.
* @see java.util.Map#get(java.lang.Object)
*/
public Object get(Object key) {
if(key==null) throw new NullPointerException("This Map does not permit null keys.");
Object object = acc.get(key);
if(object==null) {
CacheException ex = acc.getException(true);
if(ex instanceof NotARetrievableObjectException) {
throw new ClassCastException(ex.getMessage());
}
if(ex!=null) {
throw new IllegalStateException(ex.getMessage());
}
//not an error. the object did not exist.
return null;
}
return object;
}
/**
* @see javax.util.jcache.CacheAccess#put(java.lang.Object, java.lang.Object)
* @see java.util.Map#put(java.lang.Object, java.lang.Object)
* @throws IllegalArgumentException if some aspect of this key or value prevents it from being stored in this map.
*/
public Object put(Object key, Object value) {
Object prev=null;
if(acc.isPresent(key)) {
prev = acc.get(key);
}
boolean success = acc.put(key, value);
if(!success) {
CacheException ex = acc.getException(true);
if(ex instanceof CacheFullException) {
throw new IllegalArgumentException(ex.getMessage());
}
if(ex!=null) {
throw new IllegalStateException(ex.getMessage());
}
throw new IllegalStateException("Unknown error.");
}
return prev;
}
/**
* @see javax.util.jcache.CacheAccess#put(Object, String, Object)
* @see CacheMap#put(Object, String, Object)
* @throws IllegalArgumentException if some aspect of this key, group or value prevents it from being stored in this map.
*/
public Object put(Object key, String group, Object value) {
Object prev = null;
if(!acc.isPresent("group")) {
acc.defineGroup(group);
}
if(acc.isPresent(key)) {
prev=acc.get(key, group, null);
}
acc.put(key, group, value);
return prev;
}
/**Removes an object from this map. The removed object is returned.
* if the object does not exist in the cache, null is returned.
*
* @param key the object to remove.
* @return the removed object, or <tt>null</tt> if the object does not exist in FKache.
* @see java.util.Map#remove(java.lang.Object)
*/
public Object remove(Object key) {
if (key==null) {
throw new NullPointerException("This Map does not permit null keys.");
}
CacheObject obj = (CacheObject) acc.getRegion().get(key);
if(obj==null) {
return null;
}
obj.invalidate();
return obj.get();
}
public Object remove(Object key, String group) {
if (key==null || group==null) {
throw new NullPointerException("This Map does not permit null keys.");
}
CacheRegion region = acc.getRegion();
CacheGroup group2 = region.getGroup(group);
if (group2 == null) {
return null;
}
CacheObject object = (CacheObject) group2.get(key);
if(object==null) {
return null;
}
object.invalidate();
return object.get();
}
/**Adds all elements in th map into FKache.
* @param t the map which contains the elements to add.
* @throws IllegalArgumentException if some aspect of the map prevents this operation to complete.
* @throws NullPointerException if the map is <tt>null</tt>, a key is <tt>null</tt>, or any value is <tt>null</tt>.
* @see java.util.Map#putAll(java.util.Map)
*/
public void putAll(Map t) {
//naive implementation, but it works. If someone complains, I'll change it.
for (Iterator iter = t.keySet().iterator(); iter.hasNext();) {
Object key = iter.next();
acc.put(key, t.get(key));
}
}
public void clear() {
acc.invalidate();
}
public Set keySet() {
return acc.getRegion().keySet();
}
public Collection values() {
return acc.getRegion().values();
}
public Set entrySet() {
return acc.getRegion().entrySet();
}
/* (non-Javadoc)
* @see javax.util.jcache.CacheMap#getAttributes()
*/
public Attributes getAttributes() {
return acc.getAttributes();
}
/* (non-Javadoc)
* @see javax.util.jcache.CacheMap#getAttributes(java.lang.Object)
*/
public Attributes getAttributes(Object name) throws CacheException {
return acc.getAttributes(name);
}
/* (non-Javadoc)
* @see javax.util.jcache.CacheMap#get(java.lang.Object, java.lang.Object)
*/
public Object get(Object name, Object arguments) {
return acc.get(name, arguments);
}
/* (non-Javadoc)
* @see javax.util.jcache.CacheMap#defineObject(java.lang.Object, javax.util.jcache.Attributes)
*/
public void defineObject(Object name, Attributes attributes) {
acc.defineObject(name, attributes);
}
}