6937417: javac -Xprint returns IndexOutOfBoundsException

Reviewed-by: jjg

langtools/src/share/classes/com/sun/tools/javac/processing/PrintingProcessor.java

@@ -229,23 +229,24 @@ public class PrintingProcessor extends AbstractProcessor {
             if (kind == ENUM) {
                 List<Element> enclosedElements =
                     new ArrayList<Element>(e.getEnclosedElements());
+                // Handle any enum constants specially before other entities.
                 List<Element> enumConstants = new ArrayList<Element>();
                 for(Element element : enclosedElements) {
                     if (element.getKind() == ENUM_CONSTANT)
                         enumConstants.add(element);
                 }
+                if (!enumConstants.isEmpty()) {
+                    int i;
+                    for(i = 0; i < enumConstants.size()-1; i++) {
+                        this.visit(enumConstants.get(i), true);
+                        writer.print(",");
+                    }
+                    this.visit(enumConstants.get(i), true);
+                    writer.println(";\n");
 
-                int i;
-                for(i = 0; i < enumConstants.size()-1; i++) {
-                    this.visit(enumConstants.get(i), true);
-                    writer.print(",");
-                }
-                if (i >= 0 ) {
-                    this.visit(enumConstants.get(i), true);
-                    writer.print(";");
+                    enclosedElements.removeAll(enumConstants);
                 }
 
-                enclosedElements.removeAll(enumConstants);
                 for(Element element : enclosedElements)
                     this.visit(element);
             } else {

langtools/test/tools/javac/processing/model/util/elements/VacuousEnum.java

@@ -0,0 +1,33 @@
+/*
+ * Copyright 2010 Sun Microsystems, Inc.  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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
+ * CA 95054 USA or visit www.sun.com if you need additional information or
+ * have any questions.
+ */
+
+/*
+ * @test
+ * @bug 6937417
+ * @summary Test -Xprint on enum type with no constants
+ * @author  Joseph D. Darcy
+ * @compile -Xprint VacuousEnum.java
+ */
+public enum VacuousEnum {
+    // But alas, no enum constants!
+}