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FileCompare.javaAPI DocJ2ME CLDC 1.13019Wed Feb 05 15:56:04 GMT 2003util

FileCompare

public class FileCompare extends Object

Fields Summary
public static boolean
debug
Constructors Summary
Methods Summary
public static booleancmp(java.io.File a, java.io.File b)

    if ( !a.isFile() || !b.isFile()){
    if ( debug ){
        debugPrint(a, b, "not both plain files");
    }
    return false; // NotAFile compares unequal.
    }
    if ( a.length() != b.length() ){
    if ( debug ){
        debugPrint(a, b, "different lengths");
    }
    return false; // different lengthes cannot be the same.
    }
    try {
    FileInputStream astream = null;
    FileInputStream bstream = null;
    try {
        astream = new FileInputStream( a );
        bstream = new FileInputStream( b );
        long flength = a.length(); // == b.length(), remember?
        int bufsize = (int)Math.min( flength, 1024 );
        byte abuf[] = new byte[ bufsize ];
        byte bbuf[] = new byte[ bufsize ];
        long n = 0;
        while ( n < flength ){
        int naread = astream.read( abuf );
        int nbread = bstream.read( bbuf );
        if ( naread != nbread ) return false; // oops.
        for ( int i = 0; i < naread; i++ ){
            if ( abuf[i] != bbuf[i] ){
            if ( debug ){
                debugPrint(a, b, "differ at byte "+(n+i) );
            }
            return false;
            }
        }
        n += naread;
        }
    } finally {
        if ( astream != null ) astream.close();
        if ( bstream != null ) bstream.close();
    }
    } catch ( IOException e ){
    e.printStackTrace();
    return false;
    }
    if ( debug ){
    debugPrint(a, b, "are the same");
    }
    return true;
public static voidconditionalCopy(java.io.File fromFile, java.io.File toFile)

    if ( ! cmp( fromFile, toFile ) )
    cpy( fromFile, toFile );
public static booleancpy(java.io.File a, java.io.File b)

    try {
    FileInputStream astream  = null;
    FileOutputStream bstream = null;
    try {
        astream = new FileInputStream( a );
        bstream = new FileOutputStream( b );
        long flength = a.length();
        int bufsize = (int)Math.min( flength, 1024 );
        byte buf[] = new byte[ bufsize ];
        long n = 0;
        while ( n < flength ){
        int naread = astream.read( buf );
        bstream.write( buf, 0, naread );
        n += naread;
        }
    } finally {
        if ( astream != null ) astream.close();
        if ( bstream != null ) bstream.close();
    }
    } catch ( IOException e ){
    e.printStackTrace();
    return false;
    }
    return true;
private static voiddebugPrint(java.io.File a, java.io.File b, java.lang.String msg)


          
    System.err.print(a.getPath());
    System.err.print(", ");
    System.err.print(b.getPath());
    System.err.print(" ");
    System.err.println( msg );
public static voidmain(java.lang.String[] args)

    debug = true;
    conditionalCopy( new File( args[0] ), new File( args[1] ) );