ArrayIndexOutOfBoundsException when setting visibility to the caret

Question

Hi all,
I made a JTextPane and run into some problems. I get an ArrayIndexOutOfBoundsException when I'm setting it's caret visibility to true and false:
        JEditorPane textPane = new JTextPane;
        // add the textPane to a frame's ContentPane   
     public void test() {
          for(int i = 0; i<100;  i++) {
               testVisibility(true);
               testVisibility(false);
     private void testVisibility(boolean b) {
          // This is were the exception will be thrown if the text pane is visible
          // when making these calls.
          textPane.setEditable(b);
          textPane.getCaret().setVisible(b);
     }The snippet throws an ArrayIndexOutOfBoundsException:
java.lang.ArrayIndexOutOfBoundsException
     at java.lang.System.arraycopy(Native Method)
     at javax.swing.text.BoxView.updateLayoutArray(BoxView.java:197)
     at javax.swing.text.BoxView.replace(BoxView.java:168)
     at javax.swing.text.View.append(View.java:432)
     at javax.swing.text.FlowView$FlowStrategy.layout(FlowView.java:412)
     at javax.swing.text.FlowView.layout(FlowView.java:184)
     at javax.swing.text.BoxView.setSize(BoxView.java:379)
     at javax.swing.text.BoxView.updateChildSizes(BoxView.java:348)
     at javax.swing.text.BoxView.setSpanOnAxis(BoxView.java:330)
     at javax.swing.text.BoxView.layout(BoxView.java:682)
     at javax.swing.text.BoxView.setSize(BoxView.java:379)
     at javax.swing.plaf.basic.BasicTextUI$RootView.setSize(BasicTextUI.java:1618)
     at javax.swing.plaf.basic.BasicTextUI.modelToView(BasicTextUI.java:946)
     at javax.swing.text.DefaultCaret.setVisible(DefaultCaret.java:952)
     at org.seba.JTextPaneTest.testVisibility(JTextPaneTest.java:38)
     at org.seba.JTextPaneTest.test(JTextPaneTest.java:29)
     at org.seba.JTextPaneTest.main(JTextPaneTest.java:24)

Answer 1

import javax.swing.JEditorPane;
import javax.swing.JFrame;
import javax.swing.JTextPane;
public class JTextPaneTest {
     JFrame mainFrame;
     JEditorPane textPanel;
     public JTextPaneTest() {
          textPanel = new JTextPane();
        mainFrame = new JFrame("Test Frame.");
        mainFrame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        mainFrame.setSize(640, 480);
          mainFrame.getContentPane().add(textPanel);
          mainFrame.setVisible(true);
     public static void main(String[] args) {
          JTextPaneTest textPaneTest = new JTextPaneTest();
          textPaneTest.test();
     public void test() {
          for(int i = 0; i<100;  i++) {
               testVisibility(false);
               testVisibility(true);
     private void testVisibility(boolean b) {
          // This is were the exception will be thrown if the text panel is visible
          // when making these calls.
          textPanel.setEditable(b);
          textPanel.getCaret().setVisible(b);
}I hope it's ok. You'll have to use Java 5 (1.5.0.11) to compile and run it.
I run into the problem when I made the text pane not editable and the caret was still visible. I needed the caret to hide away too when making the text pane not editable. If I use the setEnabled(boolean) to disable the text pane, all the text is made grey.(I know that there are some methods to make this not happen). I just don't know why this simple test is not working as I would expect.