org.drools.core.util.FastIterator 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.
*
* 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;
public interface FastIterator {
Entry next(Entry object);
boolean isFullIterator();
public static FastIterator EMPTY = new FastIterator() {
public Entry next(Entry object) {
return null;
}
public boolean isFullIterator() {
return false;
}
public void resume(Entry target) {
}
};
public static class IteratorAdapter implements Iterator {
private final FastIterator fastIterator;
private Entry current = null;
private boolean firstConsumed = false;
public IteratorAdapter(FastIterator fastIterator, Entry first) {
this.fastIterator = fastIterator;
current = first;
}
public Object next() {
if (!firstConsumed) {
firstConsumed = true;
return current;
}
current = fastIterator.next(current);
return current;
}
}
}