java如何为所有打开的文档应用插入键操作

Question

我想对所有打开的文档应用插入键操作（在键盘上可用作“插入”键）。默认情况下，它不适用于任何文档。我为Insert key编写代码。但是，在我的程序中，插入键操作只对最近打开的文件有效。我想将此功能添加到所有打开的文件中。请检查一下

主要类别：

public class InsertDemo extends javax.swing.JFrame {
JScrollPane scrollPane;
JTextArea textArea;
public InsertDemo() {
initComponents();
}
@SuppressWarnings("unchecked")                         
private void initComponents() {
tabbedPane = new javax.swing.JTabbedPane();
jMenuBar1 = new javax.swing.JMenuBar();
file = new javax.swing.JMenu();
newFile = new javax.swing.JMenuItem();
setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);
file.setText("File");
newFile.setText("NewFile");
newFile.addActionListener(new java.awt.event.ActionListener() {
    public void actionPerformed(java.awt.event.ActionEvent evt) {
            newFileActionPerformed(evt);
    }
});
file.add(newFile);
jMenuBar1.add(file);
setJMenuBar(jMenuBar1);
javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane());
getContentPane().setLayout(layout);
layout.setHorizontalGroup(
    layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
    .addGap(0, 400, Short.MAX_VALUE)
    .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
        .addComponent(tabbedPane, javax.swing.GroupLayout.DEFAULT_SIZE, 400, Short.MAX_VALUE))
);
layout.setVerticalGroup(
    layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
    .addGap(0, 279, Short.MAX_VALUE)
    .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
        .addComponent(tabbedPane, javax.swing.GroupLayout.DEFAULT_SIZE, 279, Short.MAX_VALUE))
);

pack();
}// </editor-fold>                        

private void newFileActionPerformed(java.awt.event.ActionEvent evt) {                                        
textArea=new CaretTextArea();
scrollPane=new JScrollPane(textArea);
tabbedPane.add(scrollPane);
}                                       
public static void main(String args[]) {
try {
    for (javax.swing.UIManager.LookAndFeelInfo info : javax.swing.UIManager.getInstalledLookAndFeels()) {
        if ("Nimbus".equals(info.getName())) {
            javax.swing.UIManager.setLookAndFeel(info.getClassName());
            break;
        }
    }
} catch (ClassNotFoundException ex) {
    java.util.logging.Logger.getLogger(InsertDemo.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
} catch (InstantiationException ex) {
    java.util.logging.Logger.getLogger(InsertDemo.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
} catch (IllegalAccessException ex) {
    java.util.logging.Logger.getLogger(InsertDemo.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
} catch (javax.swing.UnsupportedLookAndFeelException ex) {
    java.util.logging.Logger.getLogger(InsertDemo.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
}

java.awt.EventQueue.invokeLater(new Runnable() {
    public void run() {
        new InsertDemo().setVisible(true);
    }
});
}                
private javax.swing.JMenu file;
private javax.swing.JMenuBar jMenuBar1;
private javax.swing.JMenuItem newFile;
private javax.swing.JTabbedPane tabbedPane;
}

插入动作类。我通过这个类创建了JtextArea引用。这是JTextArea的扩展类

public class CaretTextArea extends JTextArea {
private boolean isInsertMode=false;
Color oldCaretColor;
Color insertCaretColor=new Color(254, 254, 254);
public CaretTextArea() {
    MyCaret c=new MyCaret();
    c.setBlinkRate(getCaret().getBlinkRate());
    setCaret(c);
    oldCaretColor=getCaretColor();
    addCaretListener(new CaretListener() {
        @Override
        public void caretUpdate(CaretEvent e){
            if (isInsertMode()) {
                processCaretWidth();
            }
        }
    });

    Keymap kMap=this.getKeymap();
    Action a=new AbstractAction() {
        @Override
        public void actionPerformed(ActionEvent e) {
            setInsertMode(!isInsertMode());
        }

    };
    kMap.addActionForKeyStroke(KeyStroke.getKeyStroke(KeyEvent.VK_INSERT,0),a);
}

public boolean isInsertMode() {
    return isInsertMode;
}

public void setInsertMode(boolean insertMode) {
    isInsertMode = insertMode;
    processMode();
}

private void processMode() {
    if (isInsertMode()) {
        processCaretWidth();
        setCaretColor(insertCaretColor);
    }

    else {
        setCaretColor(oldCaretColor);
        putClientProperty("caretWidth", 1);
    }
}

private void processCaretWidth() {
    try {
        int pos=getCaretPosition();
        Rectangle rPos=modelToView(pos)!=null ? modelToView(pos).getBounds() :new Rectangle();
        int caretX=rPos.x;
        int caretEndX=rPos.x;
        if (pos<getDocument().getLength()) {
            Rectangle rNextPos=modelToView(pos+1)!=null ? modelToView(pos+1).getBounds(): new Rectangle();

            if (rPos.y==rNextPos.y) {
                caretEndX=rNextPos.x;
            }
        }
        putClientProperty("caretWidth", Math.max(1, caretEndX-caretX+1));
    } catch (BadLocationException e) {
       // e.printStackTrace();
    }
}

@Override
public void replaceSelection(String content) {
    if (isEditable() && isInsertMode() && getSelectionStart()==getSelectionEnd()) {
        int pos=getCaretPosition();
        int lastPos=Math.min(getDocument().getLength(), pos+content.length());
        select(pos, lastPos);
    }
    super.replaceSelection(content);
}

class MyCaret extends DefaultCaret {

    public void paint(Graphics g) {
        if (isInsertMode()) {
            //we should shift to half width because of DefaultCaret rendering algorithm

            AffineTransform old=((Graphics2D)g).getTransform();
            int w=(Integer)getClientProperty("caretWidth");
            g.setXORMode(Color.black);
            g.translate(w/2,0);
            super.paint(g);
            ((Graphics2D)g).setTransform(old);
        }
        else {
            super.paint(g);
        }

    }
    protected synchronized void damage(Rectangle r) {
        if (isInsertMode()) {
            if (r != null) {
                int damageWidth = (Integer)getClientProperty("caretWidth");
                x = r.x - 4 - (damageWidth/2 );
                y = r.y;
                width = 9 + 3*damageWidth/2;
                height = r.height;
                repaint();
            }
        }
        else {
            super.damage(r);
        }
    }
  }
}