8020745: Suspicious MethodParameters attribute generated for local classes capturing local variables

Corrected an error in a previous patch that caused captured locals to be added to the beginning, not the end of a parameter list.

Reviewed-by: jjg, mcimadamore, ksrini, abuckley

langtools/src/share/classes/com/sun/tools/javac/code/Symbol.java

@@ -1231,6 +1231,9 @@ public abstract class Symbol implements Element {
         /** The extra (synthetic/mandated) parameters of the method. */
         public List<VarSymbol> extraParams = List.nil();
 
+        /** The captured local variables in an anonymous class */
+        public List<VarSymbol> capturedLocals = List.nil();
+
         /** The parameters of the method. */
         public List<VarSymbol> params = null;
 

langtools/src/share/classes/com/sun/tools/javac/comp/Lower.java

@@ -2735,8 +2735,8 @@ public class Lower extends TreeTranslator {
                 for (List<VarSymbol> l = fvs; l.nonEmpty(); l = l.tail) {
                     if (TreeInfo.isInitialConstructor(tree)) {
                         final Name pName = proxyName(l.head.name);
-                        m.extraParams =
+                        m.capturedLocals =
-                            m.extraParams.append((VarSymbol)
+                            m.capturedLocals.append((VarSymbol)
                                                     (proxies.lookup(pName).sym));
                         added = added.prepend(
                           initField(tree.body.pos, pName));

langtools/src/share/classes/com/sun/tools/javac/jvm/ClassWriter.java

@@ -657,6 +657,14 @@ public class ClassWriter extends ClassFile {
                 databuf.appendChar(pool.put(s.name));
                 databuf.appendChar(flags);
             }
+            // Now write the captured locals
+            for (VarSymbol s : m.capturedLocals) {
+                final int flags =
+                    ((int) s.flags() & (FINAL | SYNTHETIC | MANDATED)) |
+                    ((int) m.flags() & SYNTHETIC);
+                databuf.appendChar(pool.put(s.name));
+                databuf.appendChar(flags);
+            }
             endAttr(attrIndex);
             return 1;
         } else

langtools/test/tools/javac/8015701/AnonymousParameters.java

@@ -1,89 +0,0 @@
-/*
- * Copyright (c) 2012, 2013, 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 8015701
- * @summary javac should generate method parameters correctly.
- * @compile -parameters AnonymousParameters.java
- * @run main AnonymousParameters
- */
-import java.lang.Class;
-import java.lang.reflect.Constructor;
-import java.lang.reflect.Parameter;
-import java.util.concurrent.Callable;
-
-public class AnonymousParameters {
-
-    String[] names = {
-        "this$0",
-        "val$message"
-    };
-
-    public static void main(String... args) throws Exception {
-        new AnonymousParameters().run();
-    }
-
-    void run() throws Exception {
-        Class<?> cls = new ParameterNames().makeInner("hello").getClass();
-        Constructor<?> ctor = cls.getDeclaredConstructors()[0];
-        Parameter[] params = ctor.getParameters();
-
-        if(params.length == 2) {
-            for(int i = 0; i < 2; i++) {
-                System.err.println("Testing parameter " + params[i].getName());
-                if(!params[i].getName().equals(names[i]))
-                    error("Expected parameter name " + names[i] +
-                          " got " + params[i].getName());
-            }
-        } else
-            error("Expected 2 parameters");
-
-        if(0 != errors)
-            throw new Exception("MethodParameters test failed with " +
-                                errors + " errors");
-    }
-
-    void error(String msg) {
-        System.err.println("Error: " + msg);
-        errors++;
-    }
-
-    int errors;
-}
-
-class ParameterNames {
-
-    public Callable<String> makeInner(final String message) {
-        return new Callable<String>()  {
-            public String call() throws Exception {
-                return message;
-            }
-        };
-    }
-
-    public static void main(String... args) throws Exception {
-        ParameterNames test = new ParameterNames();
-        System.out.println(test.makeInner("Hello").call());
-    }
-}

langtools/test/tools/javac/MethodParameters/CaptureTest.java

@@ -0,0 +1,289 @@
+/*
+ * Copyright (c) 2012, 2013, 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 8015701
+ * @summary Test method parameter attribute generation with captured locals.
+ * @compile -parameters CaptureTest.java
+ * @run main CaptureTest
+ */
+import java.lang.Class;
+import java.lang.reflect.Constructor;
+import java.lang.reflect.Parameter;
+import java.lang.reflect.Modifier;
+import java.util.List;
+import java.util.ArrayList;
+
+public class CaptureTest {
+
+    private static final int SYNTHETIC = 0x1000;
+    private static final int MANDATED = 0x8000;
+
+    public static void main(String... args) throws Exception {
+        new CaptureTest().run();
+    }
+
+
+    private void run() throws Exception {
+        final Encloser pn = new Encloser();
+
+        /* Cases covered here:
+         *
+         * - Local class
+         * - Inner class
+         * - Anonymous class
+         * - Anonymous class extending a local
+         * - Anonymous class extending an inner
+         */
+        pn.makeLocal("hello").check();
+        pn.makeInner("hello").check();
+        pn.makeAnon("hello").check();
+        pn.makeAnonExtendsLocal("hello").check();
+        pn.makeAnonExtendsInner("hello").check();
+
+        if (0 != errors)
+            throw new Exception("MethodParameters test failed with " +
+                                errors + " errors");
+    }
+
+    private void error(final String msg) {
+        System.err.println("Error: " + msg);
+        errors++;
+    }
+
+    int errors;
+
+    abstract class Tester {
+
+        public Tester(final int param) {}
+
+        protected abstract String[] names();
+        protected abstract int[] modifiers();
+        protected abstract Class[] types();
+
+        public void check() {
+            final Class<?> cls = this.getClass();
+            final Constructor<?> ctor = cls.getDeclaredConstructors()[0];
+            final Parameter[] params = ctor.getParameters();
+            final String[] names = names();
+            final int[] modifiers = modifiers();
+            final Class[] types = types();
+
+            System.err.println("Testing class " + cls);
+
+            if (params.length == names.length) {
+                for (int i = 0; i < names.length; i++) {
+                    System.err.println("Testing parameter " + params[i].getName());
+                    if (!params[i].getName().equals(names[i]))
+                        error("Expected parameter name " + names[i] +
+                              " got " + params[i].getName());
+                    if (params[i].getModifiers() != modifiers[i])
+                        error("Expected parameter modifiers " +
+                              modifiers[i] + " got " +
+                              params[i].getModifiers());
+                    if (!params[i].getType().equals(types[i]))
+                        error("Expected parameter type " + types[i] +
+                              " got " + params[i].getType());
+                }
+            } else
+                error("Expected " + names.length + " parameters");
+
+        }
+
+    }
+
+    class Encloser {
+        private class InnerTester extends Tester {
+            public InnerTester(final int innerparam) {
+                super(innerparam);
+            }
+
+            protected String[] names() {
+                return new String[] {
+                    "this$1",
+                    "innerparam"
+                };
+            }
+
+            protected int[] modifiers() {
+                return new int[] {
+                    Modifier.FINAL | SYNTHETIC,
+                    Modifier.FINAL
+                };
+            }
+
+            protected Class[] types() {
+                return new Class[] {
+                    Encloser.class,
+                    int.class
+                };
+            }
+        }
+
+        public Tester makeInner(final String message) {
+            return new InnerTester(2);
+        }
+
+        public Tester makeLocal(final String message) {
+            class LocalTester extends Tester {
+                public LocalTester(final int localparam) {
+                    super(localparam);
+                }
+
+                protected String[] names() {
+                    return new String[] {
+                        "this$1",
+                        "localparam",
+                        "val$message"
+                    };
+                }
+
+                protected int[] modifiers() {
+                    return new int[] {
+                        Modifier.FINAL | MANDATED,
+                        Modifier.FINAL,
+                        Modifier.FINAL | SYNTHETIC
+                    };
+                }
+
+                protected Class[] types() {
+                    return new Class[] {
+                        Encloser.class,
+                        int.class,
+                        String.class
+                    };
+                }
+
+                public String message() {
+                    return message;
+                }
+            }
+
+            return new LocalTester(2);
+        }
+
+        public Tester makeAnonExtendsLocal(final String message) {
+            abstract class LocalTester extends Tester {
+                public LocalTester(final int localparam) {
+                    super(localparam);
+                }
+
+                protected String[] names() {
+                    return new String[] {
+                        "this$1",
+                        "localparam",
+                        "val$message"
+                    };
+                }
+
+                protected int[] modifiers() {
+                    return new int[] {
+                        Modifier.FINAL | MANDATED,
+                        Modifier.FINAL,
+                        Modifier.FINAL | SYNTHETIC
+                    };
+                }
+
+                protected Class[] types() {
+                    return new Class[] {
+                        Encloser.class,
+                        int.class,
+                        String.class
+                    };
+                }
+
+            }
+
+            return new LocalTester(2) {
+                public String message() {
+                    return message;
+                }
+            };
+        }
+
+        public Tester makeAnonExtendsInner(final String message) {
+            return new InnerTester(2) {
+                protected String[] names() {
+                    return new String[] {
+                        "this$1",
+                        "innerparam",
+                        "val$message"
+                    };
+                }
+
+                protected int[] modifiers() {
+                    return new int[] {
+                        Modifier.FINAL | MANDATED,
+                        Modifier.FINAL,
+                        Modifier.FINAL | SYNTHETIC
+                    };
+                }
+
+                protected Class[] types() {
+                    return new Class[] {
+                        Encloser.class,
+                        int.class,
+                        String.class
+                    };
+                }
+
+                public String message() {
+                    return message;
+                }
+            };
+        }
+
+        public Tester makeAnon(final String message) {
+            return new Tester(2) {
+                protected String[] names() {
+                    return new String[] {
+                        "this$1",
+                        "param",
+                        "val$message"
+                    };
+                }
+
+                protected int[] modifiers() {
+                    return new int[] {
+                        Modifier.FINAL | MANDATED,
+                        Modifier.FINAL,
+                        Modifier.FINAL | SYNTHETIC
+                    };
+                }
+
+                protected Class[] types() {
+                    return new Class[] {
+                        Encloser.class,
+                        int.class,
+                        String.class
+                    };
+                }
+
+                public String message() {
+                    return message;
+                }
+            };
+        }
+    }
+}