Ant example source code file (FileList.java)

This example Ant source code file (FileList.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 - Ant tags/keywords

buildexception, buildexception, file, filelist, filelist, filename, fileresourceiterator, io, no, no, resourcecollection, string, string, stringtokenizer, util, vector

The FileList.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.tools.ant.types;

import java.io.File;
import java.util.StringTokenizer;
import java.util.Vector;
import java.util.Iterator;

import org.apache.tools.ant.Project;
import org.apache.tools.ant.BuildException;
import org.apache.tools.ant.types.resources.FileResourceIterator;

/**
 * FileList represents an explicitly named list of files.  FileLists
 * are useful when you want to capture a list of files regardless of
 * whether they currently exist.  By contrast, FileSet operates as a
 * filter, only returning the name of a matched file if it currently
 * exists in the file system.
 */
public class FileList extends DataType implements ResourceCollection {

    private Vector filenames = new Vector();
    private File dir;

    /**
     * The default constructor.
     *
     */
    public FileList() {
        super();
    }

    /**
     * A copy constructor.
     *
     * @param filelist a <code>FileList value
     */
    protected FileList(FileList filelist) {
        this.dir       = filelist.dir;
        this.filenames = filelist.filenames;
        setProject(filelist.getProject());
    }

    /**
     * Makes this instance in effect a reference to another FileList
     * instance.
     *
     * <p>You must not set another attribute or nest elements inside
     * this element if you make it a reference.</p>
     * @param r the reference to another filelist.
     * @exception BuildException if an error occurs.
     */
    public void setRefid(Reference r) throws BuildException {
        if ((dir != null) || (filenames.size() != 0)) {
            throw tooManyAttributes();
        }
        super.setRefid(r);
    }

    /**
     * Set the dir attribute.
     *
     * @param dir the directory this filelist is relative to.
     * @exception BuildException if an error occurs
     */
    public void setDir(File dir) throws BuildException {
        checkAttributesAllowed();
        this.dir = dir;
    }

    /**
     * @param p the current project
     * @return the directory attribute
     */
    public File getDir(Project p) {
        if (isReference()) {
            return getRef(p).getDir(p);
        }
        return dir;
    }

    /**
     * Set the filenames attribute.
     *
     * @param filenames a string contains filenames, separated by , or
     *        by whitespace.
     */
    public void setFiles(String filenames) {
        checkAttributesAllowed();
        if (filenames != null && filenames.length() > 0) {
            StringTokenizer tok = new StringTokenizer(
                filenames, ", \t\n\r\f", false);
            while (tok.hasMoreTokens()) {
               this.filenames.addElement(tok.nextToken());
            }
        }
    }

    /**
     * Returns the list of files represented by this FileList.
     * @param p the current project
     * @return the list of files represented by this FileList.
     */
    public String[] getFiles(Project p) {
        if (isReference()) {
            return getRef(p).getFiles(p);
        }

        if (dir == null) {
            throw new BuildException("No directory specified for filelist.");
        }

        if (filenames.size() == 0) {
            throw new BuildException("No files specified for filelist.");
        }

        String[] result = new String[filenames.size()];
        filenames.copyInto(result);
        return result;
    }

    /**
     * Performs the check for circular references and returns the
     * referenced FileList.
     * @param p the current project
     * @return the FileList represented by a referenced filelist.
     */
    protected FileList getRef(Project p) {
        return (FileList) getCheckedRef(p);
    }

    /**
     * Inner class corresponding to the <file> nested element.
     */
    public static class FileName {
        private String name;

        /**
         * The name attribute of the file element.
         *
         * @param name the name of a file to add to the file list.
         */
        public void setName(String name) {
            this.name = name;
        }

        /**
         * @return the name of the file for this element.
         */
        public String getName() {
            return name;
        }
    }

    /**
     * Add a nested <file> nested element.
     *
     * @param name a configured file element with a name.
     * @since Ant 1.6.2
     */
    public void addConfiguredFile(FileName name) {
        if (name.getName() == null) {
            throw new BuildException(
                "No name specified in nested file element");
        }
        filenames.addElement(name.getName());
    }

    /**
     * Fulfill the ResourceCollection contract.
     * @return an Iterator of Resources.
     * @since Ant 1.7
     */
    public Iterator iterator() {
        if (isReference()) {
            return ((FileList) getRef(getProject())).iterator();
        }
        return new FileResourceIterator(dir,
            (String[]) (filenames.toArray(new String[filenames.size()])));
    }

    /**
     * Fulfill the ResourceCollection contract.
     * @return number of elements as int.
     * @since Ant 1.7
     */
    public int size() {
        if (isReference()) {
            return ((FileList) getRef(getProject())).size();
        }
        return filenames.size();
    }

    /**
     * Always returns true.
     * @return true indicating that all elements will be FileResources.
     * @since Ant 1.7
     */
    public boolean isFilesystemOnly() {
        return true;
    }

}