home | career | drupal | java | mac | mysql | perl | scala | uml | unix  

Commons Collections example source code file (ChainedClosure.java)

This example Commons Collections source code file (ChainedClosure.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" TM.

Java - Commons Collections tags/keywords

chainedclosure, chainedclosure, closure, closure, closures, closures, illegalargumentexception, illegalargumentexception, io, iterator, serializable, util

The Commons Collections ChainedClosure.java source code

/*
 *  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.commons.collections.functors;

import java.io.Serializable;
import java.util.Collection;
import java.util.Iterator;

import org.apache.commons.collections.Closure;

/**
 * Closure implementation that chains the specified closures together.
 * 
 * @since Commons Collections 3.0
 * @version $Revision: 646777 $ $Date: 2008-04-10 13:33:15 +0100 (Thu, 10 Apr 2008) $
 *
 * @author Stephen Colebourne
 */
public class ChainedClosure implements Closure, Serializable {

    /** Serial version UID */
    private static final long serialVersionUID = -3520677225766901240L;

    /** The closures to call in turn */
    private final Closure[] iClosures;

    /**
     * Factory method that performs validation and copies the parameter array.
     * 
     * @param closures  the closures to chain, copied, no nulls
     * @return the <code>chained closure
     * @throws IllegalArgumentException if the closures array is null
     * @throws IllegalArgumentException if any closure in the array is null
     */
    public static Closure getInstance(Closure[] closures) {
        FunctorUtils.validate(closures);
        if (closures.length == 0) {
            return NOPClosure.INSTANCE;
        }
        closures = FunctorUtils.copy(closures);
        return new ChainedClosure(closures);
    }
    
    /**
     * Create a new Closure that calls each closure in turn, passing the 
     * result into the next closure. The ordering is that of the iterator()
     * method on the collection.
     * 
     * @param closures  a collection of closures to chain
     * @return the <code>chained closure
     * @throws IllegalArgumentException if the closures collection is null
     * @throws IllegalArgumentException if any closure in the collection is null
     */
    public static Closure getInstance(Collection closures) {
        if (closures == null) {
            throw new IllegalArgumentException("Closure collection must not be null");
        }
        if (closures.size() == 0) {
            return NOPClosure.INSTANCE;
        }
        // convert to array like this to guarantee iterator() ordering
        Closure[] cmds = new Closure[closures.size()];
        int i = 0;
        for (Iterator it = closures.iterator(); it.hasNext();) {
            cmds[i++] = (Closure) it.next();
        }
        FunctorUtils.validate(cmds);
        return new ChainedClosure(cmds);
    }

    /**
     * Factory method that performs validation.
     * 
     * @param closure1  the first closure, not null
     * @param closure2  the second closure, not null
     * @return the <code>chained closure
     * @throws IllegalArgumentException if either closure is null
     */
    public static Closure getInstance(Closure closure1, Closure closure2) {
        if (closure1 == null || closure2 == null) {
            throw new IllegalArgumentException("Closures must not be null");
        }
        Closure[] closures = new Closure[] { closure1, closure2 };
        return new ChainedClosure(closures);
    }

    /**
     * Constructor that performs no validation.
     * Use <code>getInstance if you want that.
     * 
     * @param closures  the closures to chain, not copied, no nulls
     */
    public ChainedClosure(Closure[] closures) {
        super();
        iClosures = closures;
    }

    /**
     * Execute a list of closures.
     * 
     * @param input  the input object passed to each closure
     */
    public void execute(Object input) {
        for (int i = 0; i < iClosures.length; i++) {
            iClosures[i].execute(input);
        }
    }

    /**
     * Gets the closures, do not modify the array.
     * @return the closures
     * @since Commons Collections 3.1
     */
    public Closure[] getClosures() {
        return iClosures;
    }

}

Other Commons Collections examples (source code examples)

Here is a short list of links related to this Commons Collections ChainedClosure.java source code file:

new blog posts

 

Copyright 1998-2016 Alvin Alexander, alvinalexander.com
All Rights Reserved.

A percentage of advertising revenue from
pages under the /java/jwarehouse URI on this website is
paid back to open source projects.