AbstractIterable.java

/***********************************************************************************************************************
 *
 * Copyright (C) 2010 by the Stratosphere project (http://stratosphere.eu)
 *
 * 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 eu.stratosphere.util;

import java.util.Iterator;

/**
 * @author Arvid Heise
 */
public abstract class AbstractIterable<T> implements Iterable<T> {

	/*
	 * (non-Javadoc)
	 * @see java.lang.Object#toString()
	 */
	@Override
	public String toString() {
		return this.toString(10);
	}

	public String toString(final int numberOfElements) {
		final StringBuilder builder = new StringBuilder(this.getClass().getSimpleName()).append(' ');
		this.appendElements(builder, this, numberOfElements);
		return builder.toString();
	}

	protected void appendElements(final StringBuilder builder, final Iterable<?> iterable, final int numberOfElements) {
		final Iterator<?> inputIterator = iterable.iterator();
		for (int input = 0; input < numberOfElements && inputIterator.hasNext(); input++)
			builder.append(inputIterator.next()).append(' ');
		if (inputIterator.hasNext())
			builder.append("...");
	}
}