com.querydsl.jpa.TransformingIterator Maven / Gradle / Ivy
/*
* Copyright 2015, The Querydsl Team (http://www.querydsl.com/team)
*
* 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.querydsl.jpa;
import java.io.Closeable;
import java.io.IOException;
import java.util.Iterator;
import com.mysema.commons.lang.CloseableIterator;
import com.querydsl.core.types.FactoryExpression;
/**
* {@code TransformingIterator} is a CloseableIterator adapter that transforms via a {@link FactoryExpression} instance
*
* @author tiwe
*
* @param
*/
public class TransformingIterator implements CloseableIterator {
private final Iterator iterator;
private final Closeable closeable;
private final FactoryExpression projection;
public TransformingIterator(Iterator iterator, FactoryExpression projection) {
this.iterator = iterator;
this.projection = projection;
this.closeable = iterator instanceof Closeable ? (Closeable) iterator : null;
}
public TransformingIterator(Iterator iterator, Closeable closeable, FactoryExpression projection) {
this.iterator = iterator;
this.projection = projection;
this.closeable = closeable;
}
@Override
public boolean hasNext() {
return iterator.hasNext();
}
@SuppressWarnings("unchecked")
@Override
public T next() {
Object result = iterator.next();
if (result != null) {
if (!result.getClass().isArray()) {
result = new Object[]{result};
}
return (T) projection.newInstance((Object[]) result);
} else {
return null;
}
}
@Override
public void remove() {
iterator.remove();
}
@Override
public void close() {
if (closeable != null) {
try {
closeable.close();
} catch (IOException e) {
throw new RuntimeException(e.getMessage(), e);
}
}
}
}