encodingmanager.java

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	public static Decoder getDecoder() {
		return (default_decoder_instance);
	}

	/*************************************************************************/

	/**
	  * This method returns the default instance of the <code>Decoder</code>
	  * for the named encoding.  This must be used only for calling the static
	  * byte array conversion methods.  Calling any instance methods on this
	  * object will result in a <code>NullPointerException</code>
	  *
	  * This form of <code>getDecoder</code> caches the instance that is returned.  If
	  * this decoder is for a complex character encoding that may use lots of
	  * memory and is only needed once or infrequently, consider using the form 
	  * of the <code>getDecoder</code> method that does not cache the results 
	  * to save resources.
	  *
	  * @param encoding The name of the encoding to retrieve a <code>Decoder</code> for.
	  *
	  * @return An instance of the <code>Decoder</code> for the named encoding.
	  *
	  * @exception UnsupportedEncodingException If a <code>Decoder</code> for the named encoding cannot be found
	  */
	public static Decoder getDecoder(String encoding) throws UnsupportedEncodingException {
		return (getDecoder(encoding, true));
	}

	/*************************************************************************/

	/**
	  * This method returns the default instance of the <code>Decoder</code>
	  * for the named encoding.  This must be used only for calling the static
	  * byte array conversion methods.  Calling any instance methods on this
	  * object will result in a <code>NullPointerException</code>
	  *
	  * @param encoding The name of the encoding to retrieve a <code>Decoder</code> for.
	  * @param cache <code>true</code> to cache this encoding, <code>false</code> otherwise
	  *
	  * @return An instance of the <code>Decoder</code> for the named encoding.
	  *
	  * @exception UnsupportedEncodingException If a <code>Decoder</code> for the named encoding cannot be found
	  */
	public static Decoder getDecoder(String encoding, boolean cache) throws UnsupportedEncodingException {
		Decoder dec = (Decoder) decoder_instances.get(encoding);
		if (dec != null)
			return (dec);

		dec = getDecoder(null, encoding, cache);

		if (cache)
			decoder_instances.put(encoding, dec);

		return (dec);
	}

	/*************************************************************************/

	/**
	  * This method returns a <code>Decoder</code> object that can read
	  * from the specified <code>InputStream</code> using the default 
	  * encoding.
	  *
	  * @param in The <code>InputStream</code> to read from
	  */
	public static Decoder getDecoder(InputStream in) {
		Object[] params = new Object[1];
		params[0] = in;

		Decoder dec = null;
		try {
			dec = (Decoder) default_decoder_cons.newInstance(params);
		} catch (Exception e) {
			throw new Error("Unexpected problems with default decoder");
		}

		return (dec);
	}

	/*************************************************************************/

	/**
	  * This method returns a <code>Decoder</code> object that can read from
	  * the specified <code>InputStream</code> using the named encoding
	  *
	  * This form of <code>getDecoder</code> caches the instance that is returned.  If
	  * this decoder is for a complex character encoding that may use lots of
	  * memory and is only needed once or infrequently, consider using the form 
	  * of the <code>getDecoder</code> method that does not cache the results 
	  * to save resources.
	  *
	  * @param in The <code>InputStream</code> to read from
	  * @param encoding The name of the character encoding scheme to use
	  *
	  * @exception UnsupportedEncodingException If a <code>Decoder</code> for this encoding cannot be found
	  */
	public static Decoder getDecoder(InputStream in, String encoding) throws UnsupportedEncodingException {
		return (getDecoder(in, encoding, true));
	}

	/*************************************************************************/

	/**
	  * This method returns a <code>Decoder</code> object that can read from
	  * the specified <code>InputStream</code> using the named encoding
	  *
	  * @param in The <code>InputStream</code> to read from
	  * @param encoding The name of the character encoding scheme to use
	  * @param cache <code>true</code> to cache the returned <code>Decoder</code>, <code>false</code> otherwise.
	  *
	  * @exception UnsupportedEncodingException If a <code>Decoder</code> for this encoding cannot be found
	  */
	public static Decoder getDecoder(InputStream in, String encoding, boolean cache) throws UnsupportedEncodingException {
		Constructor cons = findDecoderConstructor(encoding, cache);
		Object[] params = new Object[1];
		params[0] = in;

		Decoder dec = null;
		try {
			dec = (Decoder) cons.newInstance(params);
		} catch (Exception e) {
			throw new UnsupportedEncodingException(encoding + ": " + e.getMessage());
		}

		return (dec);
	}

	/*************************************************************************/

	/**
	  * This method returns the default instance of the default <code>Encoder</code> 
	  * which must be used only for calling the static byte array conversion methods.
	  * Calling any instance methods on this object will result in a 
	  * <code>NullPointerException</code>.
	  *
	  * @return An instance of the default <code>Encoder</code>.
	  */
	public static Encoder getEncoder() {
		return (default_encoder_instance);
	}

	/*************************************************************************/

	/**
	  * This method returns the default instance of the <code>Encoder</code>
	  * for the named encoding.  This must be used only for calling the static
	  * byte array conversion methods.  Calling any instance methods on this
	  * object will result in a <code>NullPointerException</code>
	  *
	  * This form of <code>getEncoder</code> caches the instance that is returned.  If
	  * this decoder is for a complex character encoding that may use lots of
	  * memory and is only needed once or infrequently, consider using the form 
	  * of the <code>getEncoder</code> method that does not cache the results 
	  * to save resources.
	  *
	  * @param encoding The name of the encoding to retrieve a <code>Encoder</code> for.
	  *
	  * @return An instance of the <code>Encoder</code> for the named encoding.
	  *
	  * @exception UnsupportedEncodingException If a <code>Encoder</code> for the named encoding cannot be found
	  */
	public static Encoder getEncoder(String encoding) throws UnsupportedEncodingException {
		return (getEncoder(encoding, true));
	}

	/*************************************************************************/

	/**
	  * This method returns the default instance of the <code>Encoder</code>
	  * for the named encoding.  This must be used only for calling the static
	  * byte array conversion methods.  Calling any instance methods on this
	  * object will result in a <code>NullPointerException</code>
	  *
	  * @param encoding The name of the encoding to retrieve a <code>Encoder</code> for.
	  * @param cache <code>true</code> to cache this encoding, <code>false</code> otherwise
	  *
	  * @return An instance of the <code>Encoder</code> for the named encoding.
	  *
	  * @exception UnsupportedEncodingException If a <code>Encoder</code> for the named encoding cannot be found
	  */
	public static Encoder getEncoder(String encoding, boolean cache) throws UnsupportedEncodingException {
		Encoder enc = (Encoder) encoder_instances.get(encoding);
		if (enc != null)
			return (enc);

		enc = getEncoder(null, encoding, cache);

		if (cache)
			encoder_instances.put(encoding, enc);

		return (enc);
	}

	/*************************************************************************/

	/**
	  * This method returns an <code>Encoder</code> object that can write
	  * to the specified <code>OutputStream</code> using the default 
	  * encoding.
	  *
	  * @param out The <code>OutputStream</code> to read from
	  */
	public static Encoder getEncoder(OutputStream out) {
		Object[] params = new Object[1];
		params[0] = out;

		Encoder enc = null;
		try {
			enc = (Encoder) default_encoder_cons.newInstance(params);
		} catch (Exception e) {
			throw new Error("Unexpected problems with default decoder");
		}

		return (enc);
	}

	/*************************************************************************/

	/**
	  * This method returns an <code>Encoder</code> object that can write to
	  * the specified <code>OutputStream</code> using the named encoding
	  *
	  * This form of <code>getencoder</code> caches the instance that is returned.  If
	  * this encoder is for a complex character encoding that may use lots of
	  * memory and is only needed once or infrequently, consider using the form 
	  * of the <code>getEncoder</code> method that does not cache the results 
	  * to save resources.
	  *
	  * @param in The <code>OutputStream</code> to read from
	  * @param encoding The name of the character encoding scheme to use
	  *
	  * @exception UnsupportedEncodingException If an <code>Encoder</code> for this encoding cannot be found
	  */
	public static Encoder getEncoder(OutputStream in, String encoding) throws UnsupportedEncodingException {
		return (getEncoder(in, encoding, true));
	}

	/*************************************************************************/

	/**
	  * This method returns an <code>Encoder</code> object that can write to
	  * the specified <code>OutputStream</code> using the named encoding
	  *
	  * @param in The <code>OutputStream</code> to read from
	  * @param encoding The name of the character encoding scheme to use
	  * @param cache <code>true</code> to cache the returned <code>Encoder</code>, <code>false</code> otherwise.
	  *
	  * @exception UnsupportedEncodingException If a <code>Decoder</code> for this encoding cannot be found
	  */
	public static Encoder getEncoder(OutputStream out, String encoding, boolean cache) throws UnsupportedEncodingException {
		Constructor cons = findEncoderConstructor(encoding, cache);
		Object[] params = new Object[1];
		params[0] = out;

		Encoder enc = null;
		try {
			enc = (Encoder) cons.newInstance(params);
		} catch (Exception e) {
			throw new UnsupportedEncodingException(encoding + ": " + e.getMessage());
		}

		return (enc);
	}

} // class EncodingManager