/*
* 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.wicket.extensions.markup.html.repeater.util;
import java.util.Collection;
import java.util.HashSet;
import java.util.Iterator;
import java.util.Set;
import org.apache.wicket.extensions.markup.html.repeater.tree.ITreeProvider;
import org.apache.wicket.model.IDetachable;
import org.apache.wicket.model.IModel;
/**
* A {@link Set} implementation utilizing a {@link ITreeProvider}'s models to keep containing
* elements.
*
* @author svenmeier
* @param <T>
* type of data
*
* @see ITreeProvider#model(Object)
*/
public class ProviderSubset<T> implements Set<T>, IDetachable
{
private static final long serialVersionUID = 1L;
private ITreeProvider<T> provider;
private Set<IModel<T>> models = new HashSet<>();
/**
* Create an empty subset.
*
* @param provider
* the provider of the complete set
*/
public ProviderSubset(ITreeProvider<T> provider)
{
this(provider, false);
}
/**
* Create a subset optionally containing all roots of the provider.
*
* @param provider
* the provider of the complete set
* @param addRoots
* should all roots be added to this subset
*/
public ProviderSubset(ITreeProvider<T> provider, boolean addRoots)
{
this.provider = provider;
if (addRoots)
{
Iterator<? extends T> roots = provider.getRoots();
while (roots.hasNext())
{
add(roots.next());
}
}
}
@Override
public void detach()
{
for (IModel<T> model : models)
{
model.detach();
}
}
@Override
public int size()
{
return models.size();
}
@Override
public boolean isEmpty()
{
return models.size() == 0;
}
@Override
public void clear()
{
detach();
models.clear();
}
@Override
public boolean contains(Object o)
{
IModel<T> model = model(o);
boolean contains = models.contains(model);
model.detach();
return contains;
}
@Override
public boolean add(T t)
{
return models.add(model(t));
}
@Override
public boolean remove(Object o)
{
IModel<T> model = model(o);
boolean removed = models.remove(model);
model.detach();
return removed;
}
@Override
public Iterator<T> iterator()
{
return new Iterator<T>()
{
private Iterator<IModel<T>> iterator = models.iterator();
private IModel<T> current;
@Override
public boolean hasNext()
{
return iterator.hasNext();
}
@Override
public T next()
{
current = iterator.next();
return current.getObject();
}
@Override
public void remove()
{
iterator.remove();
current.detach();
current = null;
}
};
}
@Override
public boolean addAll(Collection<? extends T> ts)
{
boolean changed = false;
for (T t : ts)
{
changed |= add(t);
}
return changed;
}
@Override
public boolean containsAll(Collection<?> cs)
{
for (Object c : cs)
{
if (!contains(c))
{
return false;
}
}
return true;
}
@Override
public boolean removeAll(Collection<?> cs)
{
boolean changed = false;
for (Object c : cs)
{
changed |= remove(c);
}
return changed;
}
@Override
public boolean retainAll(Collection<?> c)
{
throw new UnsupportedOperationException();
}
@Override
public Object[] toArray()
{
throw new UnsupportedOperationException();
}
@Override
public <S> S[] toArray(S[] a)
{
throw new UnsupportedOperationException();
}
@SuppressWarnings("unchecked")
private IModel<T> model(Object o)
{
return provider.model((T)o);
}
/**
* Create a model holding this set.
*
* @return model
*/
public IModel<Set<T>> createModel()
{
return new IModel<Set<T>>()
{
private static final long serialVersionUID = 1L;
@Override
public Set<T> getObject()
{
return ProviderSubset.this;
}
@Override
public void detach()
{
ProviderSubset.this.detach();
}
};
}
}