com.groupbyinc.common.apache.commons.collections4.set.UnmodifiableNavigableSet Maven / Gradle / Ivy
/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF 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 org.apache.commons.collections4.set;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.util.Collection;
import java.util.Iterator;
import java.util.NavigableSet;
import java.util.SortedSet;
import org.apache.commons.collections4.Unmodifiable;
import org.apache.commons.collections4.iterators.UnmodifiableIterator;
/**
* Decorates another NavigableSet
to ensure it can't be altered.
*
* Attempts to modify it will result in an UnsupportedOperationException.
*
* @since 4.1
* @version $Id: UnmodifiableNavigableSet.java 1686855 2015-06-22 13:00:27Z tn $
*/
public final class UnmodifiableNavigableSet
extends AbstractNavigableSetDecorator
implements Unmodifiable {
/** Serialization version */
private static final long serialVersionUID = 20150528L;
/**
* Factory method to create an unmodifiable set.
*
* @param the element type
* @param set the set to decorate, must not be null
* @return a new unmodifiable {@link NavigableSet}
* @throws NullPointerException if set is null
*/
public static NavigableSet unmodifiableNavigableSet(final NavigableSet set) {
if (set instanceof Unmodifiable) {
return set;
}
return new UnmodifiableNavigableSet(set);
}
//-----------------------------------------------------------------------
/**
* Constructor that wraps (not copies).
*
* @param set the set to decorate, must not be null
* @throws NullPointerException if set is null
*/
private UnmodifiableNavigableSet(final NavigableSet set) {
super(set);
}
//-----------------------------------------------------------------------
@Override
public Iterator iterator() {
return UnmodifiableIterator.unmodifiableIterator(decorated().iterator());
}
@Override
public boolean add(final E object) {
throw new UnsupportedOperationException();
}
@Override
public boolean addAll(final Collection extends E> coll) {
throw new UnsupportedOperationException();
}
@Override
public void clear() {
throw new UnsupportedOperationException();
}
@Override
public boolean remove(final Object object) {
throw new UnsupportedOperationException();
}
@Override
public boolean removeAll(final Collection> coll) {
throw new UnsupportedOperationException();
}
@Override
public boolean retainAll(final Collection> coll) {
throw new UnsupportedOperationException();
}
// SortedSet
//-----------------------------------------------------------------------
@Override
public SortedSet subSet(final E fromElement, final E toElement) {
final SortedSet sub = decorated().subSet(fromElement, toElement);
return UnmodifiableSortedSet.unmodifiableSortedSet(sub);
}
@Override
public SortedSet headSet(final E toElement) {
final SortedSet head = decorated().headSet(toElement);
return UnmodifiableSortedSet.unmodifiableSortedSet(head);
}
@Override
public SortedSet tailSet(final E fromElement) {
final SortedSet tail = decorated().tailSet(fromElement);
return UnmodifiableSortedSet.unmodifiableSortedSet(tail);
}
// NavigableSet
//-----------------------------------------------------------------------
@Override
public NavigableSet descendingSet() {
return unmodifiableNavigableSet(decorated().descendingSet());
}
@Override
public Iterator descendingIterator() {
return UnmodifiableIterator.unmodifiableIterator(decorated().descendingIterator());
}
@Override
public NavigableSet subSet(E fromElement, boolean fromInclusive, E toElement, boolean toInclusive) {
final NavigableSet sub = decorated().subSet(fromElement, fromInclusive, toElement, toInclusive);
return unmodifiableNavigableSet(sub);
}
@Override
public NavigableSet headSet(E toElement, boolean inclusive) {
final NavigableSet head = decorated().headSet(toElement, inclusive);
return unmodifiableNavigableSet(head);
}
@Override
public NavigableSet tailSet(E fromElement, boolean inclusive) {
final NavigableSet tail = decorated().tailSet(fromElement, inclusive);
return unmodifiableNavigableSet(tail);
}
//-----------------------------------------------------------------------
/**
* Write the collection out using a custom routine.
*
* @param out the output stream
* @throws IOException
*/
private void writeObject(final ObjectOutputStream out) throws IOException {
out.defaultWriteObject();
out.writeObject(decorated());
}
/**
* Read the collection in using a custom routine.
*
* @param in the input stream
* @throws IOException
* @throws ClassNotFoundException
*/
@SuppressWarnings("unchecked") // (1) should only fail if input stream is incorrect
private void readObject(final ObjectInputStream in) throws IOException, ClassNotFoundException {
in.defaultReadObject();
setCollection((Collection) in.readObject()); // (1)
}
}