/*
* Copyright 2014 Attila Szegedi, Daniel Dekany, Jonathan Revusky
*
* 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 freemarker.core;
import java.util.AbstractSet;
/** Don't use this; used internally by FreeMarker, might changes without notice. */
public abstract class _UnmodifiableSet<E> extends AbstractSet<E> {
@Override
public boolean add(E o) {
throw new UnsupportedOperationException();
}
@Override
public boolean remove(Object o) {
if (contains(o)) {
throw new UnsupportedOperationException();
}
return false;
}
@Override
public void clear() {
if (!isEmpty()) {
throw new UnsupportedOperationException();
}
}
}