/*----------------------------------------------------------------

  * $Id: OutputStringBuffer.java,v 1.1.1.1 2004/01/26 20:46:18 pkb Exp $

  * 

  * (c)2000 - Paul Blankenbaker

  *

  * Revision Log

  * 

  *  2000-11-16 11:19:26        Paul Blankenbaker 

  * 

  *         Created initial version

  */

 //----------------------------------------------------------------

 package com.ccg.macros;

 import java.io.*;                // needed for I/O operations

 //----------------------------------------------------------------

 /** A {@link Output Output} implementation which uses a string buffer.

  *

  * <p>This implementation is fairly efficient and useful if you want

  * to be able to get a String after interpreting macros.</p>

  * 

  * @version $Revision: 1.1.1.1 $

  * 

  * @since 1.0

  * 

  * @author $Author: pkb $

  * 

  * @see Output */

 //----------------------------------------------------------------

 public class OutputStringBuffer implements Output {

   //----------------------------------------------------------------

   /** Construct a output string buffer with the default initial capacity.

    * 

    * @since        1.0 */

   //----------------------------------------------------------------

   public OutputStringBuffer() {

     setBuffer(128);

   }

   //----------------------------------------------------------------

   /** Construct a output string buffer with a initial capacity.

    * 

    * @param        cap

    * 

    *         Initial capacity to allocate.

    * 

    * @since        1.0 */

   //----------------------------------------------------------------

   public OutputStringBuffer(int size) {

     setBuffer(size);

   }

   //----------------------------------------------------------------

   /** Construct a output buffer with a existing buffer.

    * 

    * This method allows one to contstruct a output buffer with an

    * existing {@link StringBuffer} object. This will initialize the

    * resulting output with the contents of the object passed. All data

    * which is {@link #write written} to the output buffer will be

    * appended.

    *

    * <p>It should be noted, that in this case a new {@link

    * StringBuffer} object is not allocated - the object will directly

    * append output to the {@link StringBuffer object you supply}.

    * 

    * @param        init

    * 

    *         Initial contents to load the output buffer with (any new

    *         output will be appeneded). You can pass null (buffer won't

    *         have any initial contents)

    * 

    * @since        1.0

    * 

    * @see #setBuffer(StringBuffer) */

   //----------------------------------------------------------------

   public OutputStringBuffer(StringBuffer sb) {

     setBuffer(sb);

   }

   //----------------------------------------------------------------

   /** Construct a output buffer with some initial content.

    * 

    * This method allows one to contstruct a output buffer with an

    * existing {@link String} object. This will initialize the

    * resulting output with the contents of the object passed. All data

    * which is {@link #write written} to the output buffer will be

    * appended.

    * 

    * @param        init

    * 

    *         Initial contents to load the output buffer with (any new

    *         output will be appended). You can pass null (buffer won't

    *         have any initial contents)

    * 

    * @since        1.0

    * 

    * @see #setBuffer(String) */

   //----------------------------------------------------------------

   public OutputStringBuffer(String init) {

     setBuffer(init);

   }

   //----------------------------------------------------------------

   /** One line summary...

    * 

    * Describe...

    * 

    * @param        arg1

    * 

    *         arg1-describe

    * 

    * @param        arg2

    * 

    *         arg2-describe

    * 

    * @throws        exc

    * 

    *         Why thrown

    * 

    * @return

    * 

    *         ret-description

    * 

    * @since        1.0 */

   //----------------------------------------------------------------

   public void setBuffer(StringBuffer sb) {

     if (sb != null) _buf = sb;

     else setBuffer(128);

   }

   //----------------------------------------------------------------

   /** One line summary...

    * 

    * Describe...

    * 

    * @param        arg1

    * 

    *         arg1-describe

    * 

    * @param        arg2

    * 

    *         arg2-describe

    * 

    * @throws        exc

    * 

    *         Why thrown

    * 

    * @return

    * 

    *         ret-description

    * 

    * @since        1.0 */

   //----------------------------------------------------------------

   public void setBuffer(int size) {

     _buf = ((size <= 0) ? new StringBuffer() : new StringBuffer(size));

   }

   //----------------------------------------------------------------

   /** One line summary...

    * 

    * Describe...

    * 

    * @param        arg1

    * 

    *         arg1-describe

    * 

    * @param        arg2

    * 

    *         arg2-describe

    * 

    * @throws        exc

    * 

    *         Why thrown

    * 

    * @return

    * 

    *         ret-description

    * 

    * @since        1.0 */

   //----------------------------------------------------------------

   public void setBuffer(String with) {

     _buf = (with == null) ? new StringBuffer(with) : new StringBuffer(128);

   }

   //----------------------------------------------------------------

   /** One line summary...

    * 

    * Describe...

    * 

    * @param        arg1

    * 

    *         arg1-describe

    * 

    * @param        arg2

    * 

    *         arg2-describe

    * 

    * @throws        exc

    * 

    *         Why thrown

    * 

    * @return

    * 

    *         ret-description

    * 

    * @since        1.0 */

   //----------------------------------------------------------------

   public StringBuffer getBuffer() {

     return _buf;

   }

   //----------------------------------------------------------------

   /** One line summary...

    * 

    * Describe...

    * 

    * @param        arg1

    * 

    *         arg1-describe

    * 

    * @param        arg2

    * 

    *         arg2-describe

    * 

    * @throws        exc

    * 

    *         Why thrown

    * 

    * @return

    * 

    *         ret-description

    * 

    * @since        1.0 */

   //----------------------------------------------------------------

   public void clear() {

     if (_buf != null) _buf.setLength(0);

   }

   //----------------------------------------------------------------

   /** One line summary...

    * 

    * Describe...

    * 

    * @param        arg1

    * 

    *         arg1-describe

    * 

    * @param        arg2

    * 

    *         arg2-describe

    * 

    * @throws        exc

    * 

    *         Why thrown

    * 

    * @return

    * 

    *         ret-description

    * 

    * @since        1.0 */

   //----------------------------------------------------------------

   public String toString() {

     return _buf.toString();

   }

   //----------------------------------------------------------------

   /** Writes a set of characters from a buffer to the output.

    * 

    * This method is used by macro processors (such as the {@link

    * AtMacros AtMacros} class) to send a set of characters to the

    * output device (string, file, etc).

    * 

    * @param        buf

    * 

    *         A character array to take the data from (must not be null)

    * 

    * @param        ofs

    * 

    *         Offset into the buffer to the first character to start the

    *         copy from. Should be in the range of [0,buf.length-1].

    * 

    * @param        len

    * 

    *         How many characters to copy. When added to the offset, the

    *         resulting value should not exceed the length of the array.

    * 

    * @throws        IOException

    * 

    *         If a I/O error is encountered (which this implementation of a

    *         {@link Output Output} device will probably never throw).

    * 

    * @since        1.0 */

   //----------------------------------------------------------------

   public void write(char[] buf, int ofs, int len) throws IOException {

     _buf.append(buf,ofs,len);

   }

   //----------------------------------------------------------------

   /** Appends the {@link java.lang.String string} representation of a {@link java.lang.Object Object} to the output.

    * 

    * This method is used by macro processors (such as the {@link

    * AtMacros AtMacros} class) to cause the {@link java.lang.String

    * string} representation of a {@link java.lang.Object Object} to be

    * added to the output produced.

    * 

    * @param        object

    * 

    *         The object to write out (the {@link java.lang.Object#toString

    *         toString()} method is used to write out the string

    *         representation of the object). You may pass null (in which

    *         case nothing will be done).

    * 

    * @throws        IOException

    * 

    *         If a I/O error is encountered (which this implementation of a

    *         {@link Output Output} device will probably never throw).

    * 

    * @since        1.0 */

   //----------------------------------------------------------------

   public void write(Object o) throws IOException {

     if (o != null) _buf.append(o);

   }

   //----------------------------------------------------------------  

   // private data

   //----------------------------------------------------------------

                                 // buffer to append info to on each write

   private transient StringBuffer _buf;

 }