id3v1controler.java

自己用Java写的一个mp3文件改名的小工具

import java.io.File;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.RandomAccessFile;

/**
 *  Description of the Class
 *
 * @author     kilo
 * @created    2003年12月22日
 */
public final class ID3v1Controler
		 extends ID3Interface {

	/**
	 *  Constructor for the ID3v1Controler object
	 *
	 * @param  filename                   Description of the Parameter
	 * @exception  FileNotFoundException  Description of the Exception
	 * @exception  IOException            Description of the Exception
	 * @exception  BadID3Exception        损坏的ID3标签异常
	 */
	public ID3v1Controler( Object filename )
		throws FileNotFoundException,
			IOException, BadID3Exception {
		cAFile = null;
		if ( filename instanceof String ) {
			cFile = new File( (String)filename );
			cAFile = new RandomAccessFile( (String)filename, "r" );
		}
		else if ( filename instanceof File ) {
			cFile = (File)filename;
			cAFile = new RandomAccessFile( (File)filename, "r" );

		}
		if ( cAFile == null )
			throw new BadID3Exception( "No ID3v1 flag" );
	}


	/**
	 *  Description of the Method
	 *
	 * @param  fileName                   Description of the Parameter
	 * @return                            Description of the Return Value
	 * @exception  BadID3Exception        损坏的ID3标签异常
	 * @exception  FileNotFoundException  Description of the Exception
	 * @exception  IOException            Description of the Exception
	 */
	public static boolean ID3Check( Object fileName )
		throws BadID3Exception, FileNotFoundException, IOException {
	byte[] bflag;
	String flag;
		bflag = new byte[3];
	RandomAccessFile theFile = null;
		if ( fileName instanceof String )
			theFile = new RandomAccessFile( (String)fileName, "r" );

		else if ( fileName instanceof File )
			theFile = new RandomAccessFile( (File)fileName, "r" );

		if ( theFile != null ) {
			try {
				theFile.seek( theFile.length() - 128 );
				theFile.read( bflag );
			} finally {
				theFile.close();
			}
			flag = new String( bflag );
			if ( !"TAG".equals( flag ) )
				return false;
			return true;
		}
		return false;
	}


	/**
	 *  Gets the frame attribute of the ID3v1Controler object
	 *
	 * @param  frameID              Description of the Parameter
	 * @return                      The frame value
	 * @exception  IOException      Description of the Exception
	 * @exception  BadID3Exception  Description of the Exception
	 */
	protected String getFrame( String frameID )
		throws IOException, BadID3Exception {
	byte[] bContext;
	String sContext;
	boolean findID = false;

		bContext = new byte[30];

		if ( "Title".equals( frameID ) ) {
			bContext = new byte[30];
			cAFile.seek( cAFile.length() - 125 );
			cAFile.read( bContext );
			findID = true;
		}
		else if ( "Artist".equals( frameID ) ) {
			bContext = new byte[30];
			cAFile.seek( cAFile.length() - 95 );
			cAFile.read( bContext );
			findID = true;
		}
		else if ( "Album".equals( frameID ) ) {
			bContext = new byte[30];
			cAFile.seek( cAFile.length() - 65 );
			cAFile.read( bContext );
			findID = true;
		}
		else if ( "Year".equals( frameID ) ) {
			bContext = new byte[4];
			cAFile.seek( cAFile.length() - 35 );
			cAFile.read( bContext );
			findID = true;
		}
		else if ( "Comment".equals( frameID ) ) {
			bContext = new byte[30];
			cAFile.seek( cAFile.length() - 31 );
			cAFile.read( bContext, (int)cAFile.length() - 31, 30 );
			findID = true;
		}
		else if ( "Genre".equals( frameID ) ) {
			cAFile.read( bContext, (int)cAFile.length() - 1, 1 );
			findID = true;
		}
		if ( findID )
			sContext = new String( bContext ).trim();

		else
			sContext = "";

		return sContext;
	}


	/**
	 *  Description of the Method
	 *
	 * @param  frameID  Description of the Parameter
	 * @return          Description of the Return Value
	 */
	protected String encodeFrame( String frameID ) {
	String newID;
		if ( "Title".equals( frameID ) )
			newID = "Title";

		else if ( "Artist".equals( frameID ) )
			newID = "Artist";

		else if ( "Album".equals( frameID ) )
			newID = "Album";

		else if ( "Year".equals( frameID ) )
			newID = "Year";

		else
			newID = "";

		return newID;
	}


	/**
	 *  Sets the frame attribute of the ID3v1Controler object
	 *
	 * @param  frameID   The new frame value
	 * @param  sContext  The new frame value
	 * @return           Description of the Return Value
	 */
	protected boolean setFrame( String frameID, String sContext ) {
		return false;
	}


	/**
	 *  Description of the Method
	 *
	 * @param  filename                   Description of the Parameter
	 * @exception  BadID3Exception        损坏的ID3标签异常
	 * @exception  FileNotFoundException  Description of the Exception
	 * @exception  IOException            Description of the Exception
	 */
	protected void initFiles( Object filename )
		throws BadID3Exception,
			FileNotFoundException, IOException {
	}
}