8248348: Regression caused by the update to BCEL 6.0

Reviewed-by: smarks, plevart

src/java.xml/share/classes/com/sun/org/apache/bcel/internal/generic/BranchInstruction.java

@@ -30,7 +30,7 @@ import com.sun.org.apache.bcel.internal.util.ByteSequence;
  * LOOKUPSWITCH and TABLESWITCH.
  *
  * @see InstructionList
- * @LastModified: Jan 2020
+ * @LastModified: July 2020
  */
 public abstract class BranchInstruction extends Instruction implements InstructionTargeter {
 
@@ -230,6 +230,23 @@ public abstract class BranchInstruction extends Instruction implements Instructi
         return target == ih;
     }
 
+    /**
+     * Updates the opcode. Before changing the opcode, reset the target so that
+     * the old instruction is removed from the HashSet and the new one then added.
+     * @param opcode the opcode
+     */
+    @Override
+    void setOpcode( final short opcode ) {
+        if (target == null) {
+            super.setOpcode(opcode);
+        } else {
+            // reset target before changing the opcode
+            InstructionHandle t = target;
+            setTarget(null);
+            super.setOpcode(opcode);
+            setTarget(t);
+        }
+    }
 
     /**
      * Inform target that it's not targeted anymore.

src/java.xml/share/classes/com/sun/org/apache/bcel/internal/generic/Instruction.java

@@ -29,7 +29,7 @@ import com.sun.org.apache.bcel.internal.util.ByteSequence;
 /**
  * Abstract super class for all Java byte codes.
  *
- * @LastModified: Jan 2020
+ * @LastModified: July 2020
  */
 public abstract class Instruction implements Cloneable {
 
@@ -511,7 +511,7 @@ public abstract class Instruction implements Cloneable {
     /**
      * Needed in readInstruction and subclasses in this package
      */
-    final void setOpcode( final short opcode ) {
+    void setOpcode( final short opcode ) {
         this.opcode = opcode;
     }
 

test/jaxp/javax/xml/jaxp/unittest/transform/BCELHashCodeTest.java

@@ -0,0 +1,58 @@
+/*
+ * Copyright (c) 2020, 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.
+ */
+
+package transform;
+
+import javax.xml.transform.Transformer;
+import javax.xml.transform.TransformerConfigurationException;
+import javax.xml.transform.TransformerFactory;
+import javax.xml.transform.stream.StreamSource;
+import org.testng.annotations.Test;
+
+/*
+ * @test
+ * @bug 8248348
+ * @library /javax/xml/jaxp/libs /javax/xml/jaxp/unittest
+ * @run testng transform.BCELHashCodeTest
+ * @summary The addition of the hashCode() method to Instruction.java in BCEL 6.0
+ * caused a regression. This test verifies that the issue has been fixed.
+ */
+public class BCELHashCodeTest {
+    /**
+     * Verifies the patch by attempting to create a transformer from the stylesheet.
+     * The stylesheet contains an extra table-row with element-id="17921" that
+     * causes the generated bytecode to exceed the 64Kbyte method size limit.
+     * Splitting it into multiple methods requires mutating the instructions that
+     * results in an Exception without the fix. The stylesheet would pass with
+     * or without the fix if the extra table-row is removed.
+     *
+     * @throws TransformerConfigurationException if the test fails
+     */
+    @Test
+    public void test() throws TransformerConfigurationException {
+         StreamSource stylesheet = new StreamSource(this.getClass()
+                 .getResourceAsStream("BCELHashCodeTest.xsl"));
+         TransformerFactory tFactory =TransformerFactory.newInstance();
+         Transformer transformer = tFactory.newTransformer(stylesheet);
+    }
+}