InverseSet.java

/**
 *  Copyright 2012 Universitat Pompeu Fabra.
 *
 *  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 org.onexus.ui.workspace.internal.viewers.tree;

import org.apache.wicket.model.IDetachable;

import java.util.Collection;
import java.util.Iterator;
import java.util.Set;

/**
 * An inverse set.
 *
 * @author Sven Meier
 */
public class InverseSet<T> implements Set<T>, IDetachable {

    private static final long serialVersionUID = 1L;

    private Set<T> set;

    /**
     * Create a full set.
     *
     * @param set the contained set
     */
    public InverseSet(Set<T> set) {
        this.set = set;
    }

    public void detach() {
        if (set instanceof IDetachable) {
            ((IDetachable) set).detach();
        }
    }

    public boolean isEmpty() {
        return !set.isEmpty();
    }

    public boolean contains(Object o) {
        return !set.contains(o);
    }

    public boolean add(T t) {
        return set.remove(t);
    }

    @SuppressWarnings("unchecked")
    public boolean remove(Object o) {
        return set.add((T) o);
    }

    public boolean addAll(Collection<? extends T> ts) {
        boolean changed = false;

        for (T t : ts) {
            changed |= set.remove(t);
        }

        return changed;
    }

    public boolean containsAll(Collection<?> cs) {
        for (Object c : cs) {
            if (set.contains(c)) {
                return false;
            }
        }
        return true;
    }

    @SuppressWarnings("unchecked")
    public boolean removeAll(Collection<?> cs) {
        boolean changed = false;

        for (Object c : cs) {
            changed |= set.add((T) c);
        }

        return changed;
    }

    public int size() {
        throw new UnsupportedOperationException();
    }

    public void clear() {
        throw new UnsupportedOperationException();
    }

    public Iterator<T> iterator() {
        throw new UnsupportedOperationException();
    }

    public boolean retainAll(Collection<?> c) {
        throw new UnsupportedOperationException();
    }

    public Object[] toArray() {
        throw new UnsupportedOperationException();
    }

    public <S> S[] toArray(S[] a) {
        throw new UnsupportedOperationException();
    }
}