DocCacheSupport.java

/*
 *                 Sun Public License Notice
 * 
 * The contents of this file are subject to the Sun Public License
 * Version 1.0 (the "License"). You may not use this file except in
 * compliance with the License. A copy of the License is available at
 * http://www.sun.com/
 * 
 * The Original Code is Forte for Java, Community Edition. The Initial
 * Developer of the Original Code is Sun Microsystems, Inc. Portions
 * Copyright 1997-2000 Sun Microsystems, Inc. All Rights Reserved.
 */

package org.netbeans.editor;

import java.io.Reader;
import java.io.Writer;
import java.io.IOException;
import javax.swing.text.BadLocationException;

/**
* DocCacheSupport is a base class for caching document
* which is got by some reader and enable its
* editing.
*
* @author Miloslav Metelka
* @version 1.00
*/

abstract class DocCacheSupport {

    private static final int SAVE_BUFFER_LEN = 16384;

    /** Current document length in characters */
    protected int docLen;

    /** Count of characters read */
    long statCharsRead;
    /** Count of characters written */
    long statCharsWritten;

    /** Reading from the temporary storage into destination buffer.
    * @param pos position in temp storage
    * @param buffer target storage
    * @param offset offset in buffer
    * @param len length of data in buffer to write
    */
    public abstract void read(int pos, char buffer[], int offset, int len)
    throws BadLocationException;

    /** Write buffer at the specified position. Rewrites part of the document.
    * It can write beyond the end of the document, however the initial position
    * must be inside or at the end of the document.
    * @param pos position in temp storage
    * @param buffer buffer with source data
    * @param offset offset of data in buffer
    * @param len length of data in buffer
    */
    public abstract void write(int pos, char buffer[], int offset, int len)
    throws BadLocationException;

    /** Insert buffer into the document at specified position.
    * @param pos insertion position in temp storage document
    * @param buffer source buffer with insertion data
    * @param offset offset of data in the buffer
    * @param len length of data in buffer
    */
    public abstract void insert(int pos, char buffer[], int offset, int len)
    throws BadLocationException;

    /** Insert string into the document at specified position.
    * @param pos insertion position in temp storage document
    * @param text text to insert
    * @param offset offset of data in the buffer
    * @param len length of data in buffer
    */
    public abstract void insertString(int pos, String text, int offset, int len)
    throws BadLocationException;

    /** Delete a specified count of chars at specified position.
    * @param pos position of removal in temp storage
    * @param len length of data to remove
    */
    public abstract void remove(int pos, int len) throws BadLocationException;

    /** Helps to do less allocations if the initial file size is known. By default
    * it's not implemented.
    * @param capacity space that will be preallocated
    */
    public void ensureCapacity(int capacity) {
    }

    /** Saving the tepmorary document to a writer.
    * @param writer writer where to write data from temp storage
    */
    public void save(Writer writer)
    throws IOException {
        char saveBuffer[] = new char[SAVE_BUFFER_LEN];
        int actPos = 0, len;
        while(actPos < docLen) {
            len = Math.min(docLen - actPos, SAVE_BUFFER_LEN);
            try {
                read(actPos, saveBuffer, 0, len);
            } catch(BadLocationException e) {
                if (Boolean.getBoolean("netbeans.debug.exceptions")) { // NOI18N
                    e.printStackTrace();
                }
            }
            writer.write(saveBuffer, 0, len);
            actPos += len;
        }
        writer.flush(); // flush the stream at the end
    }

    /** Destroy the CacheSupport (delete temp file etc.)
    */
    public void destroy() {
    }

    /** Getter: Document length */
    public final int getDocLength() {
        return docLen;
    }

    public boolean supportsDirectMode() {
        return false;
    }

    public char[] getDirectModeBuffer() {
        return null;
    }

}

/*
 * Log
 *  10   Gandalf-post-FCS1.8.1.0     4/3/00   Miloslav Metelka undo update
 *  9    Gandalf   1.8         1/13/00  Miloslav Metelka 
 *  8    Gandalf   1.7         1/10/00  Miloslav Metelka 
 *  7    Gandalf   1.6         10/23/99 Ian Formanek    NO SEMANTIC CHANGE - Sun
 *       Microsystems Copyright in File Comment
 *  6    Gandalf   1.5         10/10/99 Miloslav Metelka 
 *  5    Gandalf   1.4         9/10/99  Miloslav Metelka 
 *  4    Gandalf   1.3         7/20/99  Miloslav Metelka 
 *  3    Gandalf   1.2         4/23/99  Miloslav Metelka Undo added and internal 
 *       improvements
 *  2    Gandalf   1.1         2/9/99   Miloslav Metelka 
 *  1    Gandalf   1.0         2/3/99   Miloslav Metelka 
 * $
 */