audiofilewriter.java

Mobile 应用程序使用 Java Micro Edition (Java ME) 平台

/*
 * @(#)AudioFileWriter.java	1.25 05/11/17
 *
 * Copyright 2006 Sun Microsystems, Inc. All rights reserved.
 * SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 */

package javax.sound.sampled.spi;

import java.io.File;
import java.io.InputStream;
import java.io.IOException;
import java.io.OutputStream;

import javax.sound.sampled.AudioFileFormat;
import javax.sound.sampled.AudioInputStream;


/**
 * Provider for audio file writing services.  Classes providing concrete
 * implementations can write one or more types of audio file from an audio
 * stream.
 *
 * @author Kara Kytle
 * @version 1.25, 05/11/17
 * @since 1.3
 */
public abstract class AudioFileWriter {

    /**
     * Obtains the file types for which file writing support is provided by this
     * audio file writer.
     * @return array of file types.  If no file types are supported,
     * an array of length 0 is returned.
     */
    public abstract AudioFileFormat.Type[] getAudioFileTypes();


    /**
     * Indicates whether file writing support for the specified file type is provided
     * by this audio file writer.
     * @param fileType the file type for which write capabilities are queried
     * @return <code>true</code> if the file type is supported,
     * otherwise <code>false</code>
     */
    public boolean isFileTypeSupported(AudioFileFormat.Type fileType) {

	AudioFileFormat.Type types[] = getAudioFileTypes();

	for(int i=0; i<types.length; i++) {
	    if( fileType.equals( types[i] ) ) {
		return true;
	    }
	}
	return false;
    }


    /**
     * Obtains the file types that this audio file writer can write from the
     * audio input stream specified.
     * @param stream the audio input stream for which audio file type support
     * is queried
     * @return array of file types.  If no file types are supported,
     * an array of length 0 is returned.
     */
    public abstract AudioFileFormat.Type[] getAudioFileTypes(AudioInputStream stream);


    /**
     * Indicates whether an audio file of the type specified can be written
     * from the audio input stream indicated.
     * @param fileType file type for which write capabilities are queried
     * @param stream for which file writing support is queried
     * @return <code>true</code> if the file type is supported for this audio input stream,
     * otherwise <code>false</code>
     */
    public boolean isFileTypeSupported(AudioFileFormat.Type fileType, AudioInputStream stream) {

	AudioFileFormat.Type types[] = getAudioFileTypes( stream );

	for(int i=0; i<types.length; i++) {
	    if( fileType.equals( types[i] ) ) {
		return true;
	    }
	}
	return false;
    }


    /**
     * Writes a stream of bytes representing an audio file of the file type
     * indicated to the output stream provided.  Some file types require that
     * the length be written into the file header, and cannot be written from
     * start to finish unless the length is known in advance.  An attempt
     * to write such a file type will fail with an IOException if the length in
     * the audio file format is
     * {@link javax.sound.sampled.AudioSystem#NOT_SPECIFIED AudioSystem.NOT_SPECIFIED}.
     * @param stream the audio input stream containing audio data to be
     * written to the output stream
     * @param fileType file type to be written to the output stream
     * @param out stream to which the file data should be written
     * @return the number of bytes written to the output stream
     * @throws IOException if an I/O exception occurs
     * @throws IllegalArgumentException if the file type is not supported by
     * the system
     * @see #isFileTypeSupported(AudioFileFormat.Type, AudioInputStream)
     * @see #getAudioFileTypes
     */
    public abstract int write(AudioInputStream stream, AudioFileFormat.Type fileType, OutputStream out) throws IOException;


    /**
     * Writes a stream of bytes representing an audio file of the file format
     * indicated to the external file provided.
     * @param stream the audio input stream containing audio data to be
     * written to the file
     * @param fileType file type to be written to the file
     * @param out external file to which the file data should be written
     * @return the number of bytes written to the file
     * @throws IOException if an I/O exception occurs
     * @throws IllegalArgumentException if the file format is not supported by
     * the system
     * @see #isFileTypeSupported
     * @see #getAudioFileTypes
     */
    public abstract int write(AudioInputStream stream, AudioFileFormat.Type fileType, File out) throws IOException;

    
}