e1015. listening for caret movement events in a jtextcomponent.txt

这里面包含了一百多个JAVA源文件

A caret event is fired whenever the caret is moved, either by the user or by setCaretPosition(). Caret events are not fired while the mouse is being dragged. When calling setCaretPosition(), a caret event is fired only if the new position is different from the old position. 
    JTextComponent textComp = new JTextArea();
    textComp.addCaretListener(new CaretListener() {
        public void caretUpdate(CaretEvent e) {
            // dot is the caret position
            int dot = e.getDot();
    
            // mark is the non-caret end of the selection
            int mark = e.getMark();
        }
    });