/*
* 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.bag;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.util.Collection;
import java.util.Iterator;
import java.util.Set;
import org.apache.commons.collections4.SortedBag;
import org.apache.commons.collections4.Unmodifiable;
import org.apache.commons.collections4.iterators.UnmodifiableIterator;
import org.apache.commons.collections4.set.UnmodifiableSet;
Decorates another SortedBag
to ensure it can't be altered.
This class is Serializable from Commons Collections 3.1.
Attempts to modify it will result in an UnsupportedOperationException.
Type parameters: - <E> – the type of elements in this bag
Since: 3.0
/**
* Decorates another {@link SortedBag} to ensure it can't be altered.
* <p>
* This class is Serializable from Commons Collections 3.1.
* <p>
* Attempts to modify it will result in an UnsupportedOperationException.
*
* @param <E> the type of elements in this bag
* @since 3.0
*/
public final class UnmodifiableSortedBag<E>
extends AbstractSortedBagDecorator<E> implements Unmodifiable {
Serialization version /** Serialization version */
private static final long serialVersionUID = -3190437252665717841L;
Factory method to create an unmodifiable bag.
If the bag passed in is already unmodifiable, it is returned.
Params: - bag – the bag to decorate, must not be null
Type parameters: - <E> – the type of the elements in the bag
Throws: - NullPointerException – if bag is null
Returns: an unmodifiable SortedBag Since: 4.0
/**
* Factory method to create an unmodifiable bag.
* <p>
* If the bag passed in is already unmodifiable, it is returned.
*
* @param <E> the type of the elements in the bag
* @param bag the bag to decorate, must not be null
* @return an unmodifiable SortedBag
* @throws NullPointerException if bag is null
* @since 4.0
*/
public static <E> SortedBag<E> unmodifiableSortedBag(final SortedBag<E> bag) {
if (bag instanceof Unmodifiable) {
return bag;
}
return new UnmodifiableSortedBag<>(bag);
}
//-----------------------------------------------------------------------
Constructor that wraps (not copies).
Params: - bag – the bag to decorate, must not be null
Throws: - NullPointerException – if bag is null
/**
* Constructor that wraps (not copies).
*
* @param bag the bag to decorate, must not be null
* @throws NullPointerException if bag is null
*/
private UnmodifiableSortedBag(final SortedBag<E> bag) {
super(bag);
}
//-----------------------------------------------------------------------
Write the collection out using a custom routine.
Params: - out – the output stream
Throws: - IOException – if an error occurs while writing to the stream
/**
* Write the collection out using a custom routine.
*
* @param out the output stream
* @throws IOException if an error occurs while writing to the stream
*/
private void writeObject(final ObjectOutputStream out) throws IOException {
out.defaultWriteObject();
out.writeObject(decorated());
}
Read the collection in using a custom routine.
Params: - in – the input stream
Throws: - IOException – if an error occurs while reading from the stream
- ClassNotFoundException – if an object read from the stream can not be loaded
- ClassCastException – if deserialised object has wrong type
/**
* Read the collection in using a custom routine.
*
* @param in the input stream
* @throws IOException if an error occurs while reading from the stream
* @throws ClassNotFoundException if an object read from the stream can not be loaded
* @throws ClassCastException if deserialised object has wrong type
*/
@SuppressWarnings("unchecked") // will throw CCE, see Javadoc
private void readObject(final ObjectInputStream in) throws IOException, ClassNotFoundException {
in.defaultReadObject();
setCollection((Collection<E>) in.readObject());
}
//-----------------------------------------------------------------------
@Override
public Iterator<E> 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();
}
//-----------------------------------------------------------------------
@Override
public boolean add(final E object, final int count) {
throw new UnsupportedOperationException();
}
@Override
public boolean remove(final Object object, final int count) {
throw new UnsupportedOperationException();
}
@Override
public Set<E> uniqueSet() {
final Set<E> set = decorated().uniqueSet();
return UnmodifiableSet.unmodifiableSet(set);
}
}