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sun.misc
abstract public class: CharacterEncoder [javadoc | source]
java.lang.Object
   sun.misc.CharacterEncoder

Direct Known Subclasses:
    BasicBASE64Encoder, B64Encoder, HexDumpEncoder, B64Encoder, BASE64Encoder, UCEncoder, UUEncoder, B64Encoder, JarBASE64Encoder

This class defines the encoding half of character encoders. A character encoder is an algorithim for transforming 8 bit binary data into text (generally 7 bit ASCII or 8 bit ISO-Latin-1 text) for transmition over text channels such as e-mail and network news. The character encoders have been structured around a central theme that, in general, the encoded text has the form:
     [Buffer Prefix]
     [Line Prefix][encoded data atoms][Line Suffix]
     [Buffer Suffix]
In the CharacterEncoder and CharacterDecoder classes, one complete chunk of data is referred to as a buffer. Encoded buffers are all text, and decoded buffers (sometimes just referred to as buffers) are binary octets. To create a custom encoder, you must, at a minimum, overide three abstract methods in this class.
bytesPerAtom which tells the encoder how many bytes to send to encodeAtom
encodeAtom which encodes the bytes sent to it as text.
bytesPerLine which tells the encoder the maximum number of bytes per line.
Several useful encoders have already been written and are referenced in the See Also list below.
Field Summary
protected  PrintStream pStream    Stream that understands "printing" 
Method from sun.misc.CharacterEncoder Summary:
bytesPerAtom,   bytesPerLine,   encode,   encode,   encode,   encode,   encode,   encodeAtom,   encodeBuffer,   encodeBuffer,   encodeBuffer,   encodeBuffer,   encodeBuffer,   encodeBufferPrefix,   encodeBufferSuffix,   encodeLinePrefix,   encodeLineSuffix,   readFully
Methods from java.lang.Object:
clone,   equals,   finalize,   getClass,   hashCode,   notify,   notifyAll,   toString,   wait,   wait,   wait
Method from sun.misc.CharacterEncoder Detail:
 abstract protected int bytesPerAtom()
    Return the number of bytes per atom of encoding
 abstract protected int bytesPerLine()
    Return the number of bytes that can be encoded per line
 public String encode(byte[] aBuffer) 
    A 'streamless' version of encode that simply takes a buffer of bytes and returns a string containing the encoded buffer.
 public String encode(ByteBuffer aBuffer) 
    A 'streamless' version of encode that simply takes a ByteBuffer and returns a string containing the encoded buffer.

    The ByteBuffer's position will be advanced to ByteBuffer's limit.

 public  void encode(InputStream inStream,
    OutputStream outStream) throws IOException 
    Encode bytes from the input stream, and write them as text characters to the output stream. This method will run until it exhausts the input stream, but does not print the line suffix for a final line that is shorter than bytesPerLine().
 public  void encode(byte[] aBuffer,
    OutputStream aStream) throws IOException 
    Encode the buffer in aBuffer and write the encoded result to the OutputStream aStream.
 public  void encode(ByteBuffer aBuffer,
    OutputStream aStream) throws IOException 
    Encode the aBuffer ByteBuffer and write the encoded result to the OutputStream aStream.

    The ByteBuffer's position will be advanced to ByteBuffer's limit.

 abstract protected  void encodeAtom(OutputStream aStream,
    byte[] someBytes,
    int anOffset,
    int aLength) throws IOException
    Encode one "atom" of information into characters.
 public String encodeBuffer(byte[] aBuffer) 
    A 'streamless' version of encode that simply takes a buffer of bytes and returns a string containing the encoded buffer.
 public String encodeBuffer(ByteBuffer aBuffer) 
    A 'streamless' version of encode that simply takes a ByteBuffer and returns a string containing the encoded buffer.

    The ByteBuffer's position will be advanced to ByteBuffer's limit.

 public  void encodeBuffer(InputStream inStream,
    OutputStream outStream) throws IOException 
    Encode bytes from the input stream, and write them as text characters to the output stream. This method will run until it exhausts the input stream. It differs from encode in that it will add the line at the end of a final line that is shorter than bytesPerLine().
 public  void encodeBuffer(byte[] aBuffer,
    OutputStream aStream) throws IOException 
    Encode the buffer in aBuffer and write the encoded result to the OutputStream aStream.
 public  void encodeBuffer(ByteBuffer aBuffer,
    OutputStream aStream) throws IOException 
    Encode the aBuffer ByteBuffer and write the encoded result to the OutputStream aStream.

    The ByteBuffer's position will be advanced to ByteBuffer's limit.

 protected  void encodeBufferPrefix(OutputStream aStream) throws IOException 
    Encode the prefix for the entire buffer. By default is simply opens the PrintStream for use by the other functions.
 protected  void encodeBufferSuffix(OutputStream aStream) throws IOException 
    Encode the suffix for the entire buffer.
 protected  void encodeLinePrefix(OutputStream aStream,
    int aLength) throws IOException 
    Encode the prefix that starts every output line.
 protected  void encodeLineSuffix(OutputStream aStream) throws IOException 
    Encode the suffix that ends every output line. By default this method just prints a into the output stream.
 protected int readFully(InputStream in,
    byte[] buffer) throws IOException 
    This method works around the bizarre semantics of BufferedInputStream's read method.