swedit.java

Text editor implemented in Java using SWT for UI. It is intended to be a minimalist programmer s edi

      boolean link = false;
      for (int line=0; line < blockHeight; line++){
        pos = editor.getOffsetAtLine(startLine + line) + startCol;
        editor.replaceTextRange(pos, blockWidth, "");
        history.push(new Command(block[line], "", pos, link));
        // If more than one cut, the commands must be linked
        link = true;
      }
      // Clear the redo stack
      rehistory.clear();
      return new CmdReturn(true, true, false);
    }
    public String toString(){
      return "Cut Block";
    }
  }

//=============================================================================
  final class SweditCopyBlock extends SweditCommand{
    public CmdReturn exec(){
      copyBlock();
      return new CmdReturn(true, true, false);
    }
    public String toString(){
      return "Copy Block";
    }
  }
  
//=============================================================================
  // Paste a block-copied block of text into the document
  final class SweditPasteBlock extends SweditCommand{
    public CmdReturn exec(){
      // On the first (or only) line, the undo command does not need to link
      boolean link = false;
      // If text is selected, fail out
      if (editor.getSelectionCount() > 0){
        return new CmdReturn(false, true, false);
      }
      if (block == null){
        return new CmdReturn(false, true, false);
      }
      if (block.length <= 0){
        return new CmdReturn(false, true, false);
      }
      // Go through each selected line
      int startLine = getLine();
      int startCol = getColumn();
      for (int line=0; line < block.length; line++){
        // Position the caret at the start of the line
        if ((startLine + line) >= editor.getLineCount()){
          editor.setCaretOffset(editor.getCharCount() - 1);
          editor.insert("\n");
        }
        editor.setCaretOffset(editor.getOffsetAtLine(startLine + line));
        setColumn(startCol, true);
        editor.insert(block[line]);
        // Remember the command in the undo stack
        history.push(new Command("", block[line], editor.getCaretOffset(), link));
        // If more than one insert, the commands must be linked
        link = true;
      }
      // Clear the redo stack
      rehistory.clear();
      return new CmdReturn(true, true, false);
    }
    public String toString(){
      return "Paste Block";
    }
  }

//=============================================================================
  // Lots of cursor movement with selection options, largely self-explanatory
  final class SweditLineDown extends SweditCommand{
    public CmdReturn exec(){
      editor.invokeAction(ST.LINE_DOWN);
      setColumn(lastColumn, false);
      return new CmdReturn(true, true, false);
    }
    public String toString(){
      return "Line Down";
    }
  }

  final class SweditLineUp extends SweditCommand{
    public CmdReturn exec(){
      editor.invokeAction(ST.LINE_UP);
      setColumn(lastColumn, false);
      return new CmdReturn(true, true, false);
    }
    public String toString(){
      return "Line Up";
    }
  }

  final class SweditColNext extends SweditCommand{
    public CmdReturn exec(){
      editor.invokeAction(ST.COLUMN_NEXT);
      lastColumn = getColumn();
      return new CmdReturn(true, true, false);
    }
    public String toString(){
      return "Column Next";
    }
  }

  final class SweditColPrev extends SweditCommand{
    public CmdReturn exec(){
      editor.invokeAction(ST.COLUMN_PREVIOUS);
      lastColumn = getColumn();
      return new CmdReturn(true, true, false);
    }
    public String toString(){
      return "Column Previous";
    }
  }

  final class SweditWordNext extends SweditCommand{
    public CmdReturn exec(){
      editor.invokeAction(ST.WORD_NEXT);
      lastColumn = getColumn();
      return new CmdReturn(true, true, false);
    }
    public String toString(){
      return "Word Next";
    }
  }

  final class SweditWordPrev extends SweditCommand{
    public CmdReturn exec(){
      editor.invokeAction(ST.WORD_PREVIOUS);
      lastColumn = getColumn();
      return new CmdReturn(true, true, false);
    }
    public String toString(){
      return "Word Previous";
    }
  }

  final class SweditLineStart extends SweditCommand{
    public CmdReturn exec(){
      editor.invokeAction(ST.LINE_START);
      lastColumn = 1;
      return new CmdReturn(true, true, false);
    }
    public String toString(){
      return "Line Start";
    }
  }

  final class SweditLineEnd extends SweditCommand{
    public CmdReturn exec(){
      editor.invokeAction(ST.LINE_END);
      lastColumn = -1;
      return new CmdReturn(true, true, false);
    }
    public String toString(){
      return "Line End";
    }
  }

  final class SweditPageDown extends SweditCommand{
    public CmdReturn exec(){
      editor.invokeAction(ST.PAGE_DOWN);
      setColumn(lastColumn, false);
      return new CmdReturn(true, true, false);
    }
    public String toString(){
      return "Page Down";
    }
  }

  final class SweditPageUp extends SweditCommand{
    public CmdReturn exec(){
      editor.invokeAction(ST.PAGE_UP);
      setColumn(lastColumn, false);
      return new CmdReturn(true, true, false);
    }
    public String toString(){
      return "Page Up";
    }
  }

  final class SweditWindowStart extends SweditCommand{
    public CmdReturn exec(){
      editor.invokeAction(ST.WINDOW_START);
      lastColumn = 1;
      return new CmdReturn(true, true, false);
    }
    public String toString(){
      return "Window Start";
    }
  }

  final class SweditWindowEnd extends SweditCommand{
    public CmdReturn exec(){
      editor.invokeAction(ST.WINDOW_END);
      lastColumn = getColumn();
      return new CmdReturn(true, true, false);
    }
    public String toString(){
      return "Window End";
    }
  }

  final class SweditTextStart extends SweditCommand{
    public CmdReturn exec(){
      editor.invokeAction(ST.TEXT_START);
      lastColumn = 1;
      return new CmdReturn(true, true, false);
    }
    public String toString(){
      return "Text Start";
    }
  }

  final class SweditTextEnd extends SweditCommand{
    public CmdReturn exec(){
      editor.invokeAction(ST.TEXT_END);
      return new CmdReturn(true, true, false);
    }
    public String toString(){
      return "Text End";
    }
  }

  final class SweditScrollUp extends SweditCommand{
    public CmdReturn exec(){
      int index = editor.getTopIndex() + 1;
      if (index < editor.getLineCount()){
        editor.setTopIndex(index);
      }
      return new CmdReturn(false, true, false);
    }
    public String toString(){
      return "Scroll Up";
    }
  }

  final class SweditScrollDown extends SweditCommand{
    public CmdReturn exec(){
      int index = editor.getTopIndex() - 1;
      if (index > 0){
        editor.setTopIndex(index);
      }
      return new CmdReturn(false, true, false);
    }
    public String toString(){
      return "Scroll Down";
    }
  }

  final class SweditSelectLineDown extends SweditCommand{
    public CmdReturn exec(){
      editor.invokeAction(ST.SELECT_LINE_DOWN);
      return new CmdReturn(false, true, false);
    }
    public String toString(){
      return "Select Line Down";
    }
  }

  final class SweditSelectLineUp extends SweditCommand{
    public CmdReturn exec(){
      editor.invokeAction(ST.SELECT_LINE_UP);
      return new CmdReturn(false, true, false);
    }
    public String toString(){
      return "Select Line Up";
    }
  }

  final class SweditSelectColNext extends SweditCommand{
    public CmdReturn exec(){
      editor.invokeAction(ST.SELECT_COLUMN_NEXT);
      lastColumn = getColumn();
      return new CmdReturn(false, true, false);
    }
    public String toString(){
      return "Select Column Next";
    }
  }

  final class SweditSelectColPrev extends SweditCommand{
    public CmdReturn exec(){
      editor.invokeAction(ST.SELECT_COLUMN_PREVIOUS);
      lastColumn = getColumn();
      return new CmdReturn(false, true, false);
    }
    public String toString(){
      return "Select Column Previous";
    }
  }

  final class SweditSelectWordNext extends SweditCommand{
    public CmdReturn exec(){
      editor.invokeAction(ST.SELECT_WORD_NEXT);
      lastColumn = getColumn();
      return new CmdReturn(false, true, false);
    }
    public String toString(){
      return "Select Word Next";
    }
  }

  final class SweditSelectWordPrev extends SweditCommand{
    public CmdReturn exec(){
      editor.invokeAction(ST.SELECT_WORD_PREVIOUS);
      lastColumn = getColumn();
      return new CmdReturn(false, true, false);
    }
    public String toString(){
      return "Select Word Previous";
    }
  }

  final class SweditSelectLineStart extends SweditCommand{
    public CmdReturn exec(){
      editor.invokeAction(ST.SELECT_LINE_START);
      lastColumn = 1;
      return new CmdReturn(false, true, false);
    }
    public String toString(){
      return "Select To Line Start";
    }
  }

  final class SweditSelectLineEnd extends SweditCommand{
    public CmdReturn exec(){
      editor.invokeAction(ST.SELECT_LINE_END);
      lastColumn = -1;
      return new CmdReturn(false, true, false);
    }
    public String toString(){
      return "Select To Line End";
    }
  }

  final class SweditSelectPageDown extends SweditCommand{
    public CmdReturn exec(){
      editor.invokeAction(ST.SELECT_PAGE_DOWN);
      return new CmdReturn(false, true, false);
    }
    public String toString(){
      return "Select Page Down";
    }
  }

  final class SweditSelectPageUp extends SweditCommand{
    public CmdReturn exec(){