https://ant.apache.org/: master POM (The Apache Software Foundation) 
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 *  Licensed to the Apache Software Foundation (ASF) under one or more
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 *  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
 *
 *      https://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
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 *
 */
package org.apache.tools.ant.taskdefs;

import java.io.File;
import java.io.IOException;
import java.util.Map;

import org.apache.tools.ant.BuildException;
import org.apache.tools.ant.DirectoryScanner;
import org.apache.tools.ant.Project;
import org.apache.tools.ant.taskdefs.condition.Os;
import org.apache.tools.ant.types.FileSet;
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 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.

Source files and directories are only deleted when the file or
directory has been copied to the destination successfully.  Filtering
also works.


This implementation is based on Arnout Kuiper's initial design
document, the following mailing list discussions, and the
copyfile/copydir tasks.


Since:Ant 1.2
@ant.taskcategory="filesystem"
/**
 * 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</i> 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 {

    private boolean performGc = Os.isFamily("windows");

    
Constructor of object.
This sets the forceOverwrite attribute of the Copy parent class
to true.

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

    
Whether to perform a garbage collection before retrying a failed delete.

This may be required on Windows (where it is set to true by
default) but also on other operating systems, for example when
deleting directories from an NFS share.


Params:
  • b – boolean
Since:Ant 1.8.3
/**
     * Whether to perform a garbage collection before retrying a failed delete.
     *
     * <p>This may be required on Windows (where it is set to true by
     * default) but also on other operating systems, for example when
     * deleting directories from an NFS share.</p>
     *
     * @param b boolean
     * @since Ant 1.8.3
     */
    public void setPerformGcOnFailedDelete(boolean b) {
        performGc = b;
    }

    
{@inheritDoc}. 
/** {@inheritDoc}. */
    @Override
    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.

/**
     * Override copy's doFileOperations to move the files instead of copying them.
     */
    @Override
    protected void doFileOperations() {
        //Attempt complete directory renames, if any, first.
        if (completeDirMap.size() > 0) {
            for (Map.Entry<File, File> entry : completeDirMap.entrySet()) {
                File fromDir = entry.getKey();
                File toDir = entry.getValue();
                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());
                    scan(fromDir, toDir, ds.getIncludedFiles(), ds.getIncludedDirectories());
                }
            }
        }
        int moveCount = fileCopyMap.size();
        if (moveCount > 0) {   // files to move
            log("Moving " + moveCount + " file" + ((moveCount == 1) ? "" : "s")
                    + " to " + destDir.getAbsolutePath());

            for (Map.Entry<String, String[]> entry : fileCopyMap.entrySet()) {
                String fromFile = entry.getKey();
                File f = new File(fromFile);
                boolean selfMove = false;
                if (f.exists()) { //Is this file still available to be moved?
                    String[] toFiles = entry.getValue();
                    for (int i = 0; i < toFiles.length; i++) {
                        String toFile = 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) {
            int createCount = 0;
            for (Map.Entry<String, String[]> entry : dirCopyMap.entrySet()) {
                String fromDirName = entry.getKey();
                boolean selfMove = false;
                for (String toDirName : entry.getValue()) {
                    if (fromDirName.equals(toDirName)) {
                        log("Skipping self-move of " + fromDirName, verbosity);
                        selfMove = true;
                        continue;
                    }
                    File d = new File(toDirName);
                    if (!d.exists()) {
                        if (!d.mkdirs() && !d.exists()) {
                            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.

/**
     * 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) {
            throw new BuildException("Failed to rename " + fromFile + " to "
                + toFile + " due to " + ioe.getMessage(), ioe, getLocation());
        }

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

    
Copy fromFile to toFile.

Params:
  • fromFile – File
  • toFile – File
  • filtering – boolean
  • overwrite – boolean
/**
     * Copy fromFile to toFile.
     * @param fromFile File
     * @param toFile File
     * @param filtering boolean
     * @param overwrite boolean
     */
    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());
            }
            getFilterSets().forEach(executionFilters::addFilterSet);
            getFileUtils().copyFile(fromFile, toFile, executionFilters,
                                    getFilterChains(),
                                    forceOverwrite,
                                    getPreserveLastModified(),
                                    /* append: */ false,
                                    getEncoding(),
                                    getOutputEncoding(),
                                    getProject(), getForce());
        } catch (IOException ioe) {
            throw new BuildException("Failed to copy " + fromFile + " to "
                + toFile + " due to " + ioe.getMessage(), ioe, getLocation());
        }
    }

    
Its only ok to delete a directory tree if there are no files in it.

Params:
  • d – the directory to check
Returns:true if a deletion can go ahead
/**
     * 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 (String s : list) {
            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.

Params:
  • d – the directory to delete
/**
     * 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.

Params:
  • d – the directory to delete
  • deleteFiles – whether to delete files
/**
     * 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 (String s : list) {
            File f = new File(d, s);
            if (f.isDirectory()) {
                deleteDir(f);
            } else if (deleteFiles
                && !getFileUtils().tryHardToDelete(f, performGc)) {
                throw new BuildException("Unable to delete file %s",
                    f.getAbsolutePath());
            } else {
                throw new BuildException(
                    "UNEXPECTED ERROR - The file %s should not exist!",
                    f.getAbsolutePath());
            }
        }
        log("Deleting directory " + d.getAbsolutePath(), verbosity);
        if (!getFileUtils().tryHardToDelete(d, performGc)) {
            throw new BuildException("Unable to delete directory %s",
                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.

Params:
  • sourceFile – the file to rename
  • destFile –   the destination file
  • filtering –  if true, filtering is in operation, file will
                  be copied/deleted instead of renamed
  • overwrite –  if true force overwrite even if destination file
                  is newer than source file
Throws:
Returns:true if the file was renamed
/**
     * 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 {
        if (destFile.isDirectory() || filtering || !getFilterSets().isEmpty()
                || !getFilterChains().isEmpty()) {
            return false;
        }

        // identical logic lives in ResourceUtils.copyResource():
        if (destFile.isFile() && !destFile.canWrite()) {
            if (!getForce()) {
                throw new IOException(String.format(
                    "can't replace read-only destination file %s", destFile));
            }
            if (!getFileUtils().tryHardToDelete(destFile)) {
                throw new IOException(String.format(
                    "failed to delete read-only destination file %s",
                    destFile));
            }
        }

        // identical logic lives in FileUtils.rename():
        File parent = destFile.getParentFile();
        if (parent != null && !parent.exists()) {
            parent.mkdirs();
        } else if (destFile.isFile()) {
            sourceFile = getFileUtils().normalize(sourceFile.getAbsolutePath()).getCanonicalFile();
            destFile = getFileUtils().normalize(destFile.getAbsolutePath());
            if (destFile.getAbsolutePath().equals(sourceFile.getAbsolutePath())) {
                //no point in renaming a file to its own canonical version...
                log("Rename of " + sourceFile + " to " + destFile
                    + " is a no-op.", Project.MSG_VERBOSE);
                return true;
            }
            if (!getFileUtils().areSame(sourceFile, destFile)
                    && !getFileUtils().tryHardToDelete(destFile, performGc)) {
                throw new BuildException("Unable to remove existing file %s",
                    destFile);
            }
        }
        return sourceFile.renameTo(destFile);
    }
}