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/*
* Copyright (c) 2007, intarsys consulting GmbH
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* - Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
*
* - Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* - Neither the name of intarsys nor the names of its contributors may be used
* to endorse or promote products derived from this software without specific
* prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
package de.intarsys.tools.attribute;
import java.util.Map;
/**
* A default implementation for {@link IAttributeSupport}. The API is "doubled"
* to be usable as a simple replacement for a {@link Map}.
*
* null is not a legal key.
*/
final public class AttributeMap implements IAttributeSupport {
private Object[] keys;
private Object[] values;
private int length = 0;
public AttributeMap() {
this(4);
}
public AttributeMap(int initialCapacity) {
keys = new Object[initialCapacity];
values = new Object[initialCapacity];
}
synchronized public void clear() {
for (int i = 0; i < length; i++) {
values[i] = null;
keys[i] = null;
}
length = 0;
}
public Object get(Object key) {
return getAttribute(key);
}
synchronized public Object getAttribute(Object key) {
for (int i = 0; i < length; i++) {
if (keys[i].equals(key)) {
return values[i];
}
}
return null;
}
/**
* The keys used in this attribute lookup map.
*
* !! This is not intended to be published to client code, as this would
* compromise {@link IAttributeSupport} security !!
*
* @return The keys used in this attribute lookup map.
*/
public Object[] getKeys() {
Object[] tempKeys = new Object[length];
System.arraycopy(keys, 0, tempKeys, 0, length);
return tempKeys;
}
public Object put(Object key, Object o) {
return setAttribute(key, o);
}
public Object remove(Object key) {
return removeAttribute(key);
}
synchronized public Object removeAttribute(Object key) {
for (int i = 0; i < length; i++) {
if (keys[i].equals(key)) {
Object oldValue = values[i];
length--;
System.arraycopy(keys, i + 1, keys, i, length - i);
System.arraycopy(values, i + 1, values, i, length - i);
values[length] = null;
keys[length] = null;
return oldValue;
}
}
return null;
}
synchronized public Object setAttribute(Object key, Object value) {
int i = 0;
// replace existing
while (i < length) {
if (keys[i].equals(key)) {
Object oldValue = values[i];
values[i] = value;
return oldValue;
}
i++;
}
if (i >= values.length) {
// expand
Object[] newKeys = new Object[length + 4];
System.arraycopy(keys, 0, newKeys, 0, length);
keys = newKeys;
Object[] newValues = new Object[length + 4];
System.arraycopy(values, 0, newValues, 0, length);
values = newValues;
}
// add new
values[length] = value;
keys[length] = key;
length++;
return null;
}
}