--- a/jdk/src/share/classes/javax/swing/text/DefaultHighlighter.java	Sat Nov 13 19:22:38 2010 +0300
+++ b/jdk/src/share/classes/javax/swing/text/DefaultHighlighter.java	Sat Nov 13 19:31:00 2010 +0300
@@ -113,6 +113,14 @@
      * @exception BadLocationException if the specified location is invalid
      */
     public Object addHighlight(int p0, int p1, Highlighter.HighlightPainter p) throws BadLocationException {
+        if (p0 < 0) {
+            throw new BadLocationException("Invalid start offset", p0);
+        }
+
+        if (p1 < p0) {
+            throw new BadLocationException("Invalid end offset", p1);
+        }
+
         Document doc = component.getDocument();
         HighlightInfo i = (getDrawsLayeredHighlights() &&
                            (p instanceof LayeredHighlighter.LayerPainter)) ?
@@ -217,6 +225,14 @@
      * @exception BadLocationException if the specified location is invalid
      */
     public void changeHighlight(Object tag, int p0, int p1) throws BadLocationException {
+        if (p0 < 0) {
+            throw new BadLocationException("Invalid beginning of the range", p0);
+        }
+
+        if (p1 < p0) {
+            throw new BadLocationException("Invalid end of the range", p1);
+        }
+
         Document doc = component.getDocument();
         if (tag instanceof LayeredHighlightInfo) {
             LayeredHighlightInfo lhi = (LayeredHighlightInfo)tag;

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/jdk/test/javax/swing/text/DefaultHighlighter/6771184/bug6771184.java	Sat Nov 13 19:31:00 2010 +0300
@@ -0,0 +1,86 @@
+/*
+ * Copyright (c) 2010, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+/*
+ * @test
+ * @bug 6771184
+ * @summary Some methods in text package don't throw BadLocationException when expected
+ * @author Pavel Porvatov
+ */
+
+import javax.swing.*;
+import javax.swing.text.BadLocationException;
+import javax.swing.text.Highlighter;
+import javax.swing.text.JTextComponent;
+import java.awt.*;
+
+public class bug6771184 {
+    public static void main(String[] args) {
+        SwingUtilities.invokeLater(new Runnable() {
+            public void run() {
+                JTextArea textArea = new JTextArea("Tested string");
+
+                Highlighter highlighter = textArea.getHighlighter();
+                Highlighter.HighlightPainter myPainter = new Highlighter.HighlightPainter() {
+                    public void paint(Graphics g, int p0, int p1, Shape bounds, JTextComponent c) {
+                    }
+                };
+
+                int negativeTestedData[][] = {{50, 0},
+                        {-1, 1},
+                        {-5, -4},
+                        {Integer.MAX_VALUE, Integer.MIN_VALUE},
+                        {Integer.MIN_VALUE, Integer.MAX_VALUE},
+                        {Integer.MIN_VALUE, Integer.MIN_VALUE}};
+
+                for (int[] data : negativeTestedData) {
+                    try {
+                        highlighter.addHighlight(data[0], data[1], myPainter);
+
+                        throw new RuntimeException("Method addHighlight() does not throw BadLocationException for (" +
+                                data[0] + ", " + data[1] + ") ");
+                    } catch (BadLocationException e) {
+                        // Ok
+                    }
+
+                    Object objRef;
+
+                    try {
+                        objRef = highlighter.addHighlight(0, 1, myPainter);
+                    } catch (BadLocationException e) {
+                        throw new RuntimeException("highlighter.addHighlight(0, 1, myPainter) throws exception", e);
+                    }
+
+                    try {
+                        highlighter.changeHighlight(objRef, data[0], data[1]);
+
+                        throw new RuntimeException("Method changeHighlight() does not throw BadLocationException for (" +
+                                data[0] + ", " + data[1] + ") ");
+                    } catch (BadLocationException e) {
+                        // Ok
+                    }
+                }
+            }
+        });
+    }
+}