netty5/transport/src/main/java/io/netty/channel/group/CombinedIterator.java

77 lines
1.9 KiB
Java

/*
* Copyright 2012 The Netty Project
*
* The Netty Project licenses this file to you 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 io.netty.channel.group;
import java.util.Iterator;
import java.util.NoSuchElementException;
/**
*/
final class CombinedIterator<E> implements Iterator<E> {
private final Iterator<E> i1;
private final Iterator<E> i2;
private Iterator<E> currentIterator;
CombinedIterator(Iterator<E> i1, Iterator<E> i2) {
if (i1 == null) {
throw new NullPointerException("i1");
}
if (i2 == null) {
throw new NullPointerException("i2");
}
this.i1 = i1;
this.i2 = i2;
currentIterator = i1;
}
@Override
public boolean hasNext() {
for (;;) {
if (currentIterator.hasNext()) {
return true;
}
if (currentIterator == i1) {
currentIterator = i2;
} else {
return false;
}
}
}
@Override
public E next() {
for (;;) {
try {
return currentIterator.next();
} catch (NoSuchElementException e) {
if (currentIterator == i1) {
currentIterator = i2;
} else {
throw e;
}
}
}
}
@Override
public void remove() {
currentIterator.remove();
}
}