fileutils.java

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//
//                                   ____.
//                       __/\ ______|    |__/\.     _______
//            __   .____|    |       \   |    +----+       \
//    _______|  /--|    |    |    -   \  _    |    :    -   \_________
//   \\______: :---|    :    :           |    :    |         \________>
//           |__\---\_____________:______:    :____|____:_____\
//                                      /_____|
//
//                 . . . i n   j a h i a   w e   t r u s t . . .
//
//
//
//  FileUtils
//  EV      19.12.2000
//  MAP     24.01.2002  Files are stored into UTF-8 format.
//

package org.jahia.utils;

import org.jahia.exceptions.JahiaException;
import java.io.*;                       // File access methods

public class FileUtils {

    /***
        * constructor
        * EV    19.12.2000
        *
        */
    private FileUtils()
    {
        JahiaConsole.println( "FileUtils", "***** Starting fileUtils *****" );
    }

    /***
        * getInstance
        * EV    19.12.2000
        *
        */
    public static FileUtils getInstance()
    {
        if (_fileUtils == null) {
            _fileUtils = new FileUtils();
        }
        return _fileUtils;
    }

    /***
        * composeJahiaFileName
        * EV    18.11.2000
        * MAP   24.01.2002 : What's about these limitations ?
        * FIXME     : each jahia site should have its own file directory
        * FIXME     : no more than 100 files per directory
        *
        */
    public String composeJahiaFileName( String jahiaDiskPath, int jahiaID, int pageID, int fieldID )
    {
        String fileName = "";
        fileName += jahiaDiskPath + File.separator;
        fileName += Integer.toString( jahiaID ) + "-";
        fileName += Integer.toString( pageID ) + "-";
        fileName += Integer.toString( fieldID );
        fileName += ".jahia";
        return fileName;
    }

    /***
        * fileExists
        * EV    18.11.2000
        * called by loadContents
        *
        */
    public boolean fileExists( String fileName )
    throws JahiaException
    {
        try {
            File theFile = new File( fileName );
            return theFile.exists();
        } catch (SecurityException se) {
            String errorMsg = "Security error in readFile : " + se.getMessage();
            JahiaConsole.println( "FileUtils", errorMsg );
            JahiaConsole.println( "FileUtils", "Cannot read files -> BAILING OUT" );
            throw new JahiaException( "Cannot access to jahia files",
                                      errorMsg, JahiaException.FILE_ERROR, JahiaException.CRITICAL );
        }
    }

    /**
     * Read a text file in UTF-8 format.
     * Avalaible from Jahia Edition 3. The old Jahia ASCII file are also readable
     * but are saved in UTF-8 format.
     *
     * EV    18.11.2000
     * MAP   31.01.2002 Try the UTF-8 format before the the ASCII format
     *
     * @param String fileName : the absolute path file name.
     * @return : the String file _content.
     */
    public String readFile( String fileName )
    throws JahiaException
    {
        if (!tryToReadFile(fileName, UTF8)) {
            JahiaConsole.println("FileUtils.readFile", "Cannot read files in UTF-8 format trying ASCII");
            if (!tryToReadFile(fileName, ASCII)) {
                JahiaConsole.println("FileUtils.readFile", "Cannot read files -> BAILING OUT");
                throw new JahiaException( "Cannot access to jahia files",
                                          "Error in readFile : " + fileName,
                                          JahiaException.FILE_ERROR, JahiaException.ERROR );
            }
        }
        return _content;
    }

    /**
     * Write a String content to a UTF-8 file format.
     *
     * EV    18.11.2000
     * MAP   24.01.2002 Write into UTF-8 file format
     *
     * @param String fileName : the absolute path file name.
     * @param String fileContent : the String file content
     */
    public void writeFile( String fileName, String fileContent )
    throws JahiaException
    {
        try {
            BufferedWriter out = new BufferedWriter(
                                 new OutputStreamWriter(
                                 new FileOutputStream(fileName), "UTF-8"));
            out.write( fileContent );
            out.close();
        } catch (IOException ie) {
            String errorMsg = "Error in writeFile : " + fileName +
                              "\nIOException : " + ie.getMessage();
            JahiaConsole.println( "FileUtils", errorMsg );
            JahiaConsole.println( "FileUtils", "Cannot write files -> BAILING OUT" );
            throw new JahiaException(   "Cannot access to jahia files",
                                        errorMsg, JahiaException.FILE_ERROR, JahiaException.CRITICAL );
        }
    }

    /***
        * deleteFile
        * EV    07.02.2001
        *
        */
    public boolean deleteFile( String fileName )
    {
        File theFile = new File( fileName );
        return theFile.delete();
    }

    /***
        * copyStream
        * EV    30.11.2000
        * called by download
        *
        */
    public void copyStream( InputStream ins, OutputStream outs)
    throws IOException
    {
        int writeBufferSize = 4096;
        byte[] writeBuffer = new byte[writeBufferSize];

        BufferedInputStream bis = new BufferedInputStream(ins, writeBufferSize );
        BufferedOutputStream bos = new BufferedOutputStream(outs, writeBufferSize );
        int bufread;
        while((bufread = bis.read(writeBuffer )) != -1) {
            bos.write(writeBuffer, 0, bufread);
        }
        bos.flush();
        bos.close();
        bis.close();
    }

    /**
     * Try to read a file in an ASCII or UTF-8 format.
     * MAP  31.1.2002
     * @param   String fileName : The absolute path file name
     * @param   int format : The file format supposing to read;
                1 = UTF-8, any value = ASCII
     * @return  True if success, false if not.
     */
    private boolean tryToReadFile(String fileName, byte format) {
        try {
            BufferedReader in;
            if (format == UTF8) {
                in = new BufferedReader(
                     new InputStreamReader(
                     new FileInputStream(fileName), "UTF-8"));
            } else {
                in = new BufferedReader(
                     new InputStreamReader(
                     new FileInputStream(fileName)));
            }
            _content = "";
            
            StringBuffer buff = new StringBuffer();
            char[] stringToRead = new char[4096];
            int count=-1;
            while ((count=in.read(stringToRead, 0, 4096)) != -1) {
                buff.append(stringToRead, 0, count);
            }
            _content = buff.toString();
            buff = null;
            /*
            char[] stringToRead = new char[4096];
            int count=-1;
            while ((count=in.read(stringToRead, 0, 4096)) != -1) {
                _content += new String(stringToRead, 0, count);
            }
            */
            in.close();
            return true;
        } catch (IOException ie) {
            return false;
        }
    }

    private final byte ASCII = 0;
    private final byte UTF8 = 1;
    private String _content;

    private static FileUtils _fileUtils = null;
}