Java File Path Delete deleteAllFilesAux(String input, File swapFolder)

Description

Deletes all files in inputFolder backing them up in swapFolder.

License

Open Source License

Parameter

Parameter	Description
input	The name of folder (origin) whose files will be removed and backed up.
swapFolder	The temporary folder used as swap.

Exception

Parameter	Description
IOException	Thrown when it is not possible to copy a file.

Return

The first file that could not be deleted.

Declaration

private static File deleteAllFilesAux(String input, File swapFolder) throws IOException 

Method Source Code

//package com.java2s;
import java.io.File;

import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;

public class Main {
    /**/* w w w  . j a v a2  s  . c  om*/
     * Deletes all files in inputFolder backing them up in <code>swapFolder</code>. This method
     * had to be implemented since file.canWrite() together with file.delete() do not work properly
     * due to a JAVA bug. See http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=4041126.
     * 
     * @param input The name of folder (origin) whose files will be removed and backed up.
     * @param swapFolder The temporary folder used as swap.
     * @return The first file that could not be deleted.
     * @throws IOException Thrown when it is not possible to copy a file.
     */
    private static File deleteAllFilesAux(String input, File swapFolder) throws IOException {
        File result = null;
        /* creates a file from the input */
        File file = new File(input);
        if (file.exists()) // verifies if the file exists
        {
            if (file.isDirectory()) // checks if it is a directory
            {
                File originalFolder = file; // keeps a reference from the current folder
                File swap = null;

                /*
                 * creates the directory trying to keep the same directory structure in the swap
                 * folder
                 */
                swap = new File(swapFolder + getSeparator() + file.getName());
                swap.mkdir();

                /* Iterates over all elements of the current directory 'file' */
                File[] files = file.listFiles();
                for (File file2 : files) {
                    result = deleteAllFilesAux(file2.getAbsolutePath(), swap);
                    if (result != null) {
                        break;
                    }
                }
                if (result == null) {
                    originalFolder.delete();
                }
            } else {
                /* copies the file to the swap directory */
                copyFiles(new String[] { file.getAbsolutePath() }, swapFolder.getAbsolutePath(), false);

                /* tries to delete the current file */
                if (!file.delete()) {
                    result = file;
                } else {
                    result = null;
                }
            }
        }
        return result;
    }

    /**
     * Returns the system separator.
     * 
     * @return The system separator string.
     */
    public static String getSeparator() {
        return System.getProperty("file.separator");
    }

    /**
     * Copy a list of files to a specifc folder.
     * 
     * @param sourceFiles An array containing the name of the files to be copied.
     * @param toDir The destination forlder.
     * @param overwrite Indicates if the existing files in the destination folder will be
     * overwritten.
     * @return The new absolute file names.
     * @throws IOException If there is a file in the destination folder with same source name.
     */
    public static String[] copyFiles(String[] sourceFiles, String toDir, boolean overwrite) throws IOException {
        String[] newFileNames = new String[sourceFiles.length];
        for (int i = 0; i < sourceFiles.length; i++) {
            File inFile = new File(sourceFiles[i]);
            File outFile = new File(toDir + getSeparator() + inFile.getName());
            boolean fileExists = false;
            if (outFile.exists()) {
                fileExists = true;
                if (overwrite) {
                    if (!outFile.delete()) {
                        throw new IOException(outFile.getAbsolutePath() + " cannot be overwritten.");
                    }
                    fileExists = false;
                }
            }

            if (!fileExists) {
                byte[] b = new byte[(int) inFile.length()];
                InputStream in = new FileInputStream(inFile);
                OutputStream out = new FileOutputStream(outFile);
                in.read(b);
                out.write(b);
                out.close();
                in.close();
                newFileNames[i] = outFile.getAbsolutePath();
            }
        }
        return newFileNames; // return the new locations
    }
}

Related

1. deleteAllFiles(File directory)
2. deleteAllFiles(File dirOrFile)
3. deleteAllFiles(String directory)
4. deleteAllFiles(String folder, String type)
5. deleteAllFiles(Vector filesToDelete)
6. deleteAllFilesIn(String dir)
7. deleteAllFilesInDir(File dir)
8. deleteAllFilesInDirectory(String path)
9. deleteAllFilesOnlyInDirectory(File startingDir)