org.apache.flink.runtime.util.SerializableArrayList Maven / Gradle / Ivy
/*
* 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.flink.runtime.util;
import java.io.IOException;
import java.util.ArrayList;
import org.apache.flink.core.io.IOReadableWritable;
import org.apache.flink.core.memory.DataInputView;
import org.apache.flink.core.memory.DataOutputView;
import org.apache.flink.util.StringUtils;
/**
* This class extends a standard {@link java.util.ArrayList} by implementing the
* {@link org.apache.flink.core.io.IOReadableWritable} interface.
*
* @param
* the type of object stored inside this array list
*/
public class SerializableArrayList extends ArrayList implements IOReadableWritable {
private static final long serialVersionUID = 8196856588290198537L;
/**
* Constructs an empty list with an initial capacity of ten.
*/
public SerializableArrayList() {
super();
}
/**
* Constructs an empty list with the specified initial capacity.
*
* @param initialCapacity
* the initial capacity of the list
*/
public SerializableArrayList(final int initialCapacity) {
super(initialCapacity);
}
@Override
public void write(final DataOutputView out) throws IOException {
out.writeInt(size());
for (E element : this) {
// Write out type
StringUtils.writeNullableString(element.getClass().getName(), out);
// Write out element itself
element.write(out);
}
}
@Override
public void read(final DataInputView in) throws IOException {
// Make sure the list is empty
clear();
final int numberOfElements = in.readInt();
for (int i = 0; i < numberOfElements; i++) {
final String elementType = StringUtils.readNullableString(in);
E element;
try {
@SuppressWarnings("unchecked")
Class clazz = (Class) Class.forName(elementType);
element = clazz.newInstance();
}
catch (ClassNotFoundException e) {
throw new IOException(e);
}
catch (Exception e) {
throw new IOException(e);
}
element.read(in);
add(element);
}
}
@Override
public boolean equals(Object obj) {
return obj instanceof SerializableArrayList && super.equals(obj);
}
}