Ant example source code file (Move.java)

This example Ant source code file (Move.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

attempting, buildexception, buildexception, enumeration, failed, file, file, fileset, io, ioexception, skipping, string, string, unable, unable, util

The Move.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.taskdefs;

import java.io.File;
import java.io.IOException;
import java.util.Enumeration;
import org.apache.tools.ant.Project;
import org.apache.tools.ant.BuildException;
import org.apache.tools.ant.DirectoryScanner;
import org.apache.tools.ant.types.FileSet;
import org.apache.tools.ant.types.FilterSet;
import org.apache.tools.ant.types.FilterSetCollection;

/**
 * Moves a file or directory to a new file or directory.
 * By default, the
 * destination file is overwritten if it already exists.
 * When <i>overwrite is
 * turned off, then files are only moved if the source file is
 * newer than the destination file, or when the destination file does
 * not exist.
 *
 * <p>Source files and directories are only deleted when the file or
 * directory has been copied to the destination successfully.  Filtering
 * also works.</p>
 *
 * <p>This implementation is based on Arnout Kuiper's initial design
 * document, the following mailing list discussions, and the
 * copyfile/copydir tasks.</p>
 *
 *
 * @since Ant 1.2
 *
 * @ant.task category="filesystem"
 */
public class Move extends Copy {

    /**
     * Constructor of object.
     * This sets the forceOverwrite attribute of the Copy parent class
     * to true.
     *
     */
    public Move() {
        super();
        setOverwrite(true);
    }

    /** {@inheritDoc}. */
    protected void validateAttributes() throws BuildException {
        if (file != null && file.isDirectory()) {
            if ((destFile != null && destDir != null)
                || (destFile == null && destDir == null)) {
                throw new BuildException("One and only one of tofile and todir "
                                         + "must be set.");
            }
            destFile = (destFile == null)
                ? new File(destDir, file.getName()) : destFile;
            destDir = (destDir == null)
                ? destFile.getParentFile() : destDir;

            completeDirMap.put(file, destFile);
            file = null;
        } else {
            super.validateAttributes();
        }
    }

//************************************************************************
//  protected and private methods
//************************************************************************

    /**
     * Override copy's doFileOperations to move the
     * files instead of copying them.
     */
    protected void doFileOperations() {
        //Attempt complete directory renames, if any, first.
        if (completeDirMap.size() > 0) {
            Enumeration e = completeDirMap.keys();
            while (e.hasMoreElements()) {
                File fromDir = (File) e.nextElement();
                File toDir = (File) completeDirMap.get(fromDir);
                boolean renamed = false;
                try {
                    log("Attempting to rename dir: " + fromDir
                        + " to " + toDir, verbosity);
                    renamed =
                        renameFile(fromDir, toDir, filtering, forceOverwrite);
                } catch (IOException ioe) {
                    String msg = "Failed to rename dir " + fromDir
                        + " to " + toDir
                        + " due to " + ioe.getMessage();
                    throw new BuildException(msg, ioe, getLocation());
                }
                if (!renamed) {
                    FileSet fs = new FileSet();
                    fs.setProject(getProject());
                    fs.setDir(fromDir);
                    addFileset(fs);
                    DirectoryScanner ds = fs.getDirectoryScanner(getProject());
                    String[] files = ds.getIncludedFiles();
                    String[] dirs = ds.getIncludedDirectories();
                    scan(fromDir, toDir, files, dirs);
                }
            }
        }
        int moveCount = fileCopyMap.size();
        if (moveCount > 0) {   // files to move
            log("Moving " + moveCount + " file"
                + ((moveCount == 1) ? "" : "s")
                + " to " + destDir.getAbsolutePath());

            Enumeration e = fileCopyMap.keys();
            while (e.hasMoreElements()) {
                String fromFile = (String) e.nextElement();

                File f = new File(fromFile);
                boolean selfMove = false;
                if (f.exists()) { //Is this file still available to be moved?
                    String[] toFiles = (String[]) fileCopyMap.get(fromFile);
                    for (int i = 0; i < toFiles.length; i++) {
                        String toFile = (String) toFiles[i];

                        if (fromFile.equals(toFile)) {
                            log("Skipping self-move of " + fromFile, verbosity);
                            selfMove = true;

                            // if this is the last time through the loop then
                            // move will not occur, but that's what we want
                            continue;
                        }
                        File d = new File(toFile);
                        if ((i + 1) == toFiles.length && !selfMove) {
                            // Only try to move if this is the last mapped file
                            // and one of the mappings isn't to itself
                            moveFile(f, d, filtering, forceOverwrite);
                        } else {
                            copyFile(f, d, filtering, forceOverwrite);
                        }
                    }
                }
            }
        }

        if (includeEmpty) {
            Enumeration e = dirCopyMap.keys();
            int createCount = 0;
            while (e.hasMoreElements()) {
                String fromDirName = (String) e.nextElement();
                String[] toDirNames = (String[]) dirCopyMap.get(fromDirName);
                boolean selfMove = false;
                for (int i = 0; i < toDirNames.length; i++) {

                    if (fromDirName.equals(toDirNames[i])) {
                        log("Skipping self-move of " + fromDirName, verbosity);
                        selfMove = true;
                        continue;
                    }

                    File d = new File(toDirNames[i]);
                    if (!d.exists()) {
                        if (!d.mkdirs()) {
                            log("Unable to create directory "
                                + d.getAbsolutePath(), Project.MSG_ERR);
                        } else {
                            createCount++;
                        }
                    }
                }

                File fromDir = new File(fromDirName);
                if (!selfMove && okToDelete(fromDir)) {
                    deleteDir(fromDir);
                }

            }

            if (createCount > 0) {
                log("Moved " + dirCopyMap.size()
                    + " empty director"
                    + (dirCopyMap.size() == 1 ? "y" : "ies")
                    + " to " + createCount
                    + " empty director"
                    + (createCount == 1 ? "y" : "ies") + " under "
                    + destDir.getAbsolutePath());
            }
        }
    }

    /**
     * Try to move the file via a rename, but if this fails or filtering
     * is enabled, copy the file then delete the sourceFile.
     */
    private void moveFile(File fromFile, File toFile,
                          boolean filtering, boolean overwrite) {
        boolean moved = false;
        try {
            log("Attempting to rename: " + fromFile
                + " to " + toFile, verbosity);
            moved = renameFile(fromFile, toFile, filtering, forceOverwrite);
        } catch (IOException ioe) {
            String msg = "Failed to rename " + fromFile
                + " to " + toFile
                + " due to " + ioe.getMessage();
            throw new BuildException(msg, ioe, getLocation());
        }

        if (!moved) {
            copyFile(fromFile, toFile, filtering, overwrite);
            if (!fromFile.delete()) {
                throw new BuildException("Unable to delete "
                                        + "file "
                                        + fromFile.getAbsolutePath());
            }
        }
    }

    /**
     * Copy fromFile to toFile.
     * @param fromFile
     * @param toFile
     * @param filtering
     * @param overwrite
     */
    private void copyFile(File fromFile, File toFile,
                          boolean filtering, boolean overwrite) {
        try {
            log("Copying " + fromFile + " to " + toFile,
                verbosity);

            FilterSetCollection executionFilters =
                new FilterSetCollection();
            if (filtering) {
                executionFilters
                    .addFilterSet(getProject().getGlobalFilterSet());
            }
            for (Enumeration filterEnum =
                    getFilterSets().elements();
                filterEnum.hasMoreElements();) {
                executionFilters
                    .addFilterSet((FilterSet) filterEnum
                                .nextElement());
            }

            getFileUtils().copyFile(fromFile, toFile, executionFilters,
                                    getFilterChains(),
                                    forceOverwrite,
                                    getPreserveLastModified(),
                                    getEncoding(),
                                    getOutputEncoding(),
                                    getProject());

        } catch (IOException ioe) {
            String msg = "Failed to copy " + fromFile
                + " to " + toFile
                + " due to " + ioe.getMessage();
            throw new BuildException(msg, ioe, getLocation());
        }
    }


    /**
     * Its only ok to delete a directory tree if there are
     * no files in it.
     * @param d the directory to check
     * @return true if a deletion can go ahead
     */
    protected boolean okToDelete(File d) {
        String[] list = d.list();
        if (list == null) {
            return false;
        }     // maybe io error?

        for (int i = 0; i < list.length; i++) {
            String s = list[i];
            File f = new File(d, s);
            if (f.isDirectory()) {
                if (!okToDelete(f)) {
                    return false;
                }
            } else {
                return false;   // found a file
            }
        }

        return true;
    }

    /**
     * Go and delete the directory tree.
     * @param d the directory to delete
     */
    protected void deleteDir(File d) {
        deleteDir(d, false);
    }

    /**
     * Go and delete the directory tree.
     * @param d the directory to delete
     * @param deleteFiles whether to delete files
     */
    protected void deleteDir(File d, boolean deleteFiles) {
        String[] list = d.list();
        if (list == null) {
            return;
        }      // on an io error list() can return null

        for (int i = 0; i < list.length; i++) {
            String s = list[i];
            File f = new File(d, s);
            if (f.isDirectory()) {
                deleteDir(f);
            } else if (deleteFiles && !(f.delete())) {
                throw new BuildException("Unable to delete file "
                                         + f.getAbsolutePath());
            } else {
                throw new BuildException("UNEXPECTED ERROR - The file "
                                         + f.getAbsolutePath()
                                         + " should not exist!");
            }
        }
        log("Deleting directory " + d.getAbsolutePath(), verbosity);
        if (!d.delete()) {
            throw new BuildException("Unable to delete directory "
                                     + d.getAbsolutePath());
        }
    }

    /**
     * Attempts to rename a file from a source to a destination.
     * If overwrite is set to true, this method overwrites existing file
     * even if the destination file is newer.  Otherwise, the source file is
     * renamed only if the destination file is older than it.
     * Method then checks if token filtering is used.  If it is, this method
     * returns false assuming it is the responsibility to the copyFile method.
     *
     * @param sourceFile the file to rename
     * @param destFile   the destination file
     * @param filtering  if true, filtering is in operation, file will
     *                   be copied/deleted instead of renamed
     * @param overwrite  if true force overwrite even if destination file
     *                   is newer than source file
     * @return true if the file was renamed
     * @exception IOException if an error occurs
     * @exception BuildException if an error occurs
     */
    protected boolean renameFile(File sourceFile, File destFile,
                                 boolean filtering, boolean overwrite)
        throws IOException, BuildException {

        boolean renamed = false;
        if ((getFilterSets().size() + getFilterChains().size() == 0)
            && !(filtering || destFile.isDirectory())) {
            // ensure that parent dir of dest file exists!
            File parent = destFile.getParentFile();
            if (parent != null && !parent.exists()) {
                parent.mkdirs();
            }
            if (destFile.isFile() && !destFile.equals(sourceFile)
                && !destFile.delete()) {
                throw new BuildException("Unable to remove existing "
                                         + "file " + destFile);
            }
            renamed = sourceFile.renameTo(destFile);
        }
        return renamed;
    }
}