org.drools.core.util.Bag Maven / Gradle / Ivy
/*
* Copyright 2015 Red Hat, Inc. and/or its affiliates.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.drools.core.util;
import java.io.Serializable;
import java.util.*;
import java.util.Iterator;
public class Bag implements Collection, Serializable {
private Map map = new HashMap();
private int size = 0;
@Override
public int size() {
return size;
}
public int getKeySize() {
return map.size();
}
public int sizeFor(T t) {
Counter i = map.get(t);
return i != null ? i.get() : 0;
}
@Override
public boolean isEmpty() {
return map.isEmpty();
}
@Override
public boolean contains( Object o ) {
return map.containsKey( o );
}
@Override
public Iterator iterator() {
return map.keySet().iterator();
}
@Override
public Object[] toArray() {
return map.keySet().toArray();
}
@Override
public T1[] toArray( T1[] a ) {
return map.keySet().toArray( a );
}
@Override
public boolean add( T t ) {
Counter i = map.get(t);
if (i == null) {
map.put( t, new Counter() );
} else {
i.increment();
}
size++;
return true;
}
@Override
public boolean remove( Object o ) {
Counter i = map.get(o);
if (i == null) {
return false;
}
if (i.decrement()) {
map.remove( o );
}
size--;
return true;
}
public boolean removeKey( Object o ) {
Counter i = map.remove(o);
if (i != null) {
size -= i.get();
return true;
}
return false;
}
@Override
public boolean containsAll( Collection c ) {
return map.keySet().containsAll( c );
}
@Override
public boolean addAll( Collection c ) {
for (T t : c) {
add(t);
}
return true;
}
@Override
public boolean removeAll( Collection c ) {
boolean result = false;
for (Object o : c) {
result = remove(o) || result;
}
return result;
}
@Override
public boolean retainAll( Collection c ) {
throw new UnsupportedOperationException();
}
@Override
public void clear() {
map.clear();
size = 0;
}
@Override
public String toString() {
return map.toString();
}
public static class Counter implements Serializable {
private int count;
public Counter() {
this(1);
}
public Counter(int count) {
this.count = count;
}
public void increment() {
count++;
}
public boolean decrement() {
return --count == 0;
}
public int get() {
return count;
}
@Override
public String toString() {
return "" + count;
}
}
}