/*
* Copyright 2011 Google Inc.
*
* 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 com.google.web.bindery.autobean.shared.impl;
import com.google.web.bindery.autobean.shared.Splittable;
import com.google.web.bindery.autobean.shared.impl.AutoBeanCodexImpl.Coder;
import com.google.web.bindery.autobean.shared.impl.AutoBeanCodexImpl.EncodeState;
import java.util.AbstractList;
/**
* A list implementation that lazily reifies its constituent elements.
*
* @param <E> the element type
*/
public class SplittableList<E> extends AbstractList<E> implements HasSplittable {
static <Q> Q reify(EncodeState state, Splittable data, int index, Coder coder) {
if (data.isNull(index)) {
return null;
}
@SuppressWarnings("unchecked")
Q toReturn = (Q) coder.decode(state, data.get(index));
data.setReified(String.valueOf(index), toReturn);
return toReturn;
}
static void set(EncodeState state, Splittable data, int index, Coder coder, Object value) {
data.setReified(String.valueOf(index), value);
if (value == null) {
Splittable.NULL.assign(data, index);
return;
}
Splittable backing = coder.extractSplittable(state, value);
if (backing == null) {
/*
* External data type, such as an ArrayList or a concrete implementation
* of a setter's interface type. This means that a slow serialization pass
* is necessary.
*/
data.setReified(AbstractAutoBean.UNSPLITTABLE_VALUES_KEY, true);
} else {
backing.assign(data, index);
}
}
private Splittable data;
private final Coder elementCoder;
private final EncodeState state;
public SplittableList(Splittable data, Coder elementCoder, EncodeState state) {
assert data.isIndexed() : "Expecting indexed data";
this.data = data;
this.elementCoder = elementCoder;
this.state = state;
}
@Override
public void add(int index, E element) {
set(state, data, index, elementCoder, element);
}
@Override
public E get(int index) {
if (data.isReified(String.valueOf(index))) {
@SuppressWarnings("unchecked")
E toReturn = (E) data.getReified(String.valueOf(index));
return toReturn;
}
// javac generics bug
return SplittableList.<E> reify(state, data, index, elementCoder);
}
public Splittable getSplittable() {
return data;
}
@Override
public E remove(int index) {
E toReturn = get(index);
// XXX This is terrible, use Array.splice
int newSize = data.size() - 1;
for (int i = index; i < newSize; i++) {
data.get(i + 1).assign(data, i);
// reified value for index 'i' may needs to be updated
if (data.isReified(String.valueOf(i + 1))) {
data.setReified(String.valueOf(i), data.getReified(String.valueOf(i + 1)));
} else if (data.isReified(String.valueOf(i))) {
// Remove outdated value. Will be regenerated if needed.
data.removeReified(String.valueOf(i));
}
}
// clean-up last entry as one element has been removed
data.removeReified(String.valueOf(newSize));
data.setSize(newSize);
return toReturn;
}
@Override
public E set(int index, E element) {
E previous = get(index);
set(state, data, index, elementCoder, element);
return previous;
}
@Override
public int size() {
return data.size();
}
}