Separates finalize() methods from the generated dealloc methods. Catc…

…h and swallow exceptions thrown by finalize().

This fixes other potential issues with finalizers, for example ensuring that the finalizer is executed before any fields are cleaned up.
	Change on 2016/02/01 by kstanger <kstanger@google.com>
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=113535791

jre_emul/Classes/IOSReference.m

@@ -20,6 +20,7 @@
 #import "IOSReference.h"
 
 #import "IOSClass.h"
+#import "J2ObjC_source.h"
 #import "java/lang/ref/PhantomReference.h"
 #import "java/lang/ref/Reference.h"
 #import "java/lang/ref/SoftReference.h"
@@ -306,6 +307,9 @@ static void ReferentSubclassDealloc(id self, SEL _cmd) {
         }
       }
 
+      // The class swizzling causes finalize not to be called from the
+      // referent's dealloc, so we call it here.
+      JreFinalize(self);
       // Real dealloc.
       RealReferentDealloc(self);
       // Remove reference associations.

jre_emul/Classes/J2ObjC_common.m

@@ -24,6 +24,8 @@
 #import "java/lang/AssertionError.h"
 #import "java/lang/ClassCastException.h"
 #import "java/lang/NullPointerException.h"
+#import "java/util/logging/Level.h"
+#import "java/util/logging/Logger.h"
 #import "java_lang_IntegralToString.h"
 #import "java_lang_RealToString.h"
 
@@ -59,6 +61,17 @@ id nil_chk(id __unsafe_unretained p) {
 }
 #endif
 
+void JreFinalize(id self) {
+  @try {
+    [self javaFinalize];
+  } @catch (JavaLangThrowable *e) {
+    [JavaUtilLoggingLogger_getLoggerWithNSString_([[self getClass] getName])
+        logWithJavaUtilLoggingLevel:JavaUtilLoggingLevel_get_WARNING()
+                       withNSString:@"Uncaught exception in finalizer"
+              withJavaLangThrowable:e];
+  }
+}
+
 id JreStrongAssign(__strong id *pIvar, id value) {
   return JreAutoreleasedAssign(pIvar, [value retain]);
 }

jre_emul/Classes/J2ObjC_source.h

@@ -68,6 +68,14 @@ FOUNDATION_EXPORT void JreThrowAssertionError(id __unsafe_unretained msg);
 FOUNDATION_EXPORT void JreRelease(id obj);
 #endif
 
+FOUNDATION_EXPORT void JreFinalize(id self);
+
+__attribute__((always_inline)) inline void JreCheckFinalize(id self, Class cls) {
+  if ([self class] == cls) {
+    JreFinalize(self);
+  }
+}
+
 /*!
  * Macros that simplify the syntax for loading of static fields.
  *

jre_emul/Classes/JavaObject.h

@@ -44,6 +44,9 @@
 - (void)waitWithLong:(long long)timeout;
 - (void)waitWithLong:(long long)timeout withInt:(int)nanos;
 
+// Called upon deallocation of the object.
+- (void)javaFinalize;
+
 @end
 
 #endif // _JavaObject_H_

jre_emul/Classes/NSObject+JavaObject.m

@@ -160,6 +160,9 @@ - (void)waitWithLong:(long long)timeout withInt:(int)nanos {
   doWait(self, timeout + (nanos == 0 ? 0 : 1));
 }
 
+- (void)javaFinalize {
+}
+
 - (void)__javaClone:(id)original {
 }
 
@@ -171,7 +174,7 @@ + (const J2ObjcClassInfo *)__metadata {
     { "isEqual:", "equals", "Z", 0x1, NULL, NULL },
     { "clone", NULL, "Ljava.lang.Object;", 0x4, "Ljava.lang.CloneNotSupportedException;", NULL },
     { "description", "toString", "Ljava.lang.String;", 0x1, NULL, NULL },
-    { "dealloc", "finalize", "V", 0x4, "Ljava.lang.Throwable;", NULL },
+    { "javaFinalize", "finalize", "V", 0x4, "Ljava.lang.Throwable;", NULL },
     { "notify", NULL, "V", 0x11, NULL, NULL },
     { "notifyAll", NULL, "V", 0x11, NULL, NULL },
     { "waitWithLong:", "wait", "V", 0x11, "Ljava.lang.InterruptedException;", NULL },

translator/src/main/java/com/google/devtools/j2objc/translate/DestructorGenerator.java

@@ -23,13 +23,13 @@
 import com.google.devtools.j2objc.ast.ExpressionStatement;
 import com.google.devtools.j2objc.ast.FunctionInvocation;
 import com.google.devtools.j2objc.ast.MethodDeclaration;
+import com.google.devtools.j2objc.ast.NativeStatement;
 import com.google.devtools.j2objc.ast.PrefixExpression;
 import com.google.devtools.j2objc.ast.SimpleName;
 import com.google.devtools.j2objc.ast.Statement;
 import com.google.devtools.j2objc.ast.SuperMethodInvocation;
 import com.google.devtools.j2objc.ast.TreeUtil;
 import com.google.devtools.j2objc.ast.TreeVisitor;
-import com.google.devtools.j2objc.ast.TryStatement;
 import com.google.devtools.j2objc.ast.TypeDeclaration;
 import com.google.devtools.j2objc.ast.VariableDeclarationFragment;
 import com.google.devtools.j2objc.types.FunctionBinding;
@@ -55,64 +55,49 @@
 public class DestructorGenerator extends TreeVisitor {
 
   @Override
-  public boolean visit(TypeDeclaration node) {
+  public void endVisit(TypeDeclaration node) {
     if (node.isInterface()) {
-      return true;
-    }
-    MethodDeclaration destructor = findDestructor(node);
-    if (destructor != null && Options.useARC()) {
-      removeSuperFinalizeStatement(destructor.getBody());
+      return;
     }
+
+    ITypeBinding type = node.getTypeBinding();
+    boolean hasFinalize = hasFinalizeMethod(type);
     List<Statement> releaseStatements = createReleaseStatements(node);
-    if (destructor == null && !releaseStatements.isEmpty()) {
-      // No destructor, so create a new one if there are releasable fields.
-      destructor = buildFinalizeMethod(node.getTypeBinding());
-      node.getBodyDeclarations().add(destructor);
+    if (releaseStatements.isEmpty() && !hasFinalize) {
+      return;
     }
-    if (destructor != null) {
-      addReleaseStatements(destructor, releaseStatements);
-    }
-    return true;
-  }
 
-  private MethodDeclaration findDestructor(TypeDeclaration node) {
-    for (MethodDeclaration method : TreeUtil.getMethodDeclarations(node)) {
-      if (BindingUtil.isDestructor(method.getMethodBinding())) {
-        return method;
-      }
+    ITypeBinding voidType = typeEnv.resolveJavaType("void");
+    int modifiers = Modifier.PUBLIC | BindingUtil.ACC_SYNTHETIC;
+    GeneratedMethodBinding deallocBinding = GeneratedMethodBinding.newMethod(
+        NameTable.DEALLOC_METHOD, modifiers, voidType, type);
+    MethodDeclaration deallocDecl = new MethodDeclaration(deallocBinding);
+    Block block = new Block();
+    deallocDecl.setBody(block);
+    List<Statement> stmts = block.getStatements();
+    if (hasFinalize) {
+      String clsName = nameTable.getFullName(type);
+      stmts.add(new NativeStatement("JreCheckFinalize(self, [" + clsName + " class]);"));
+    }
+    stmts.addAll(releaseStatements);
+    if (Options.useReferenceCounting()) {
+      stmts.add(new ExpressionStatement(new SuperMethodInvocation(typeEnv.getDeallocMethod())));
     }
-    return null;
-  }
 
-  private void removeSuperFinalizeStatement(Block body) {
-    body.accept(new TreeVisitor() {
-      @Override
-      public boolean visit(final ExpressionStatement node) {
-        Expression e = node.getExpression();
-        if (e instanceof SuperMethodInvocation) {
-          IMethodBinding m = ((SuperMethodInvocation) e).getMethodBinding();
-          if (BindingUtil.isDestructor(m)) {
-            node.remove();
-            return false;
-          }
-        }
-        return true;
-      }
-    });
+    node.getBodyDeclarations().add(deallocDecl);
   }
 
-  private SuperMethodInvocation findSuperFinalizeInvocation(MethodDeclaration node) {
-    // Find existing super.finalize(), if any.
-    final SuperMethodInvocation[] superFinalize = new SuperMethodInvocation[1];
-    node.accept(new TreeVisitor() {
-      @Override
-      public void endVisit(SuperMethodInvocation node) {
-        if (BindingUtil.isDestructor(node.getMethodBinding())) {
-          superFinalize[0] = node;
-        }
+  private boolean hasFinalizeMethod(ITypeBinding type) {
+    if (type == null || typeEnv.isJavaObjectType(type)) {
+      return false;
+    }
+    for (IMethodBinding method : type.getDeclaredMethods()) {
+      if (method.getName().equals(NameTable.FINALIZE_METHOD)
+          && method.getParameterTypes().length == 0) {
+        return true;
       }
-    });
-    return superFinalize[0];
+    }
+    return hasFinalizeMethod(type.getSuperclass());
   }
 
   private List<Statement> createReleaseStatements(TypeDeclaration node) {
@@ -145,42 +130,4 @@ private Statement createRelease(IVariableBinding var) {
     releaseInvocation.getArguments().add(arg);
     return new ExpressionStatement(releaseInvocation);
   }
-
-  private void addReleaseStatements(MethodDeclaration method, List<Statement> releaseStatements) {
-    SuperMethodInvocation superFinalize = findSuperFinalizeInvocation(method);
-
-    List<Statement> statements = method.getBody().getStatements();
-    if (superFinalize != null) {
-      // Release statements must be inserted before the [super dealloc] call.
-      statements =
-          TreeUtil.asStatementList(TreeUtil.getOwningStatement(superFinalize)).subList(0, 0);
-    } else if (!statements.isEmpty() && statements.get(0) instanceof TryStatement) {
-      TryStatement tryStatement = ((TryStatement) statements.get(0));
-      if (tryStatement.getBody() != null) {
-        statements = tryStatement.getBody().getStatements();
-      }
-    }
-
-    statements.addAll(releaseStatements);
-
-    if (Options.useReferenceCounting() && superFinalize == null) {
-      IMethodBinding methodBinding = method.getMethodBinding();
-      GeneratedMethodBinding binding = GeneratedMethodBinding.newMethod(
-          NameTable.DEALLOC_METHOD, Modifier.PUBLIC, typeEnv.mapTypeName("void"),
-          methodBinding.getDeclaringClass());
-      SuperMethodInvocation call = new SuperMethodInvocation(binding);
-      ExpressionStatement stmt = new ExpressionStatement(call);
-      statements.add(stmt);
-    }
-  }
-
-  private MethodDeclaration buildFinalizeMethod(ITypeBinding declaringClass) {
-    ITypeBinding voidType = typeEnv.mapTypeName("void");
-    int modifiers = Modifier.PUBLIC | BindingUtil.ACC_SYNTHETIC;
-    GeneratedMethodBinding binding = GeneratedMethodBinding.newMethod(
-        NameTable.DEALLOC_METHOD, modifiers, voidType, declaringClass);
-    MethodDeclaration method = new MethodDeclaration(binding);
-    method.setBody(new Block());
-    return method;
-  }
 }

translator/src/main/java/com/google/devtools/j2objc/translate/Functionizer.java

@@ -125,8 +125,7 @@ private boolean canFunctionize(MethodDeclaration node) {
 
     // Never functionize these types of methods.
     if (Modifier.isStatic(modifiers) || Modifier.isAbstract(modifiers)
-        || BindingUtil.isSynthetic(modifiers) || m.isAnnotationMember()
-        || BindingUtil.isDestructor(m)) {
+        || BindingUtil.isSynthetic(modifiers) || m.isAnnotationMember()) {
       return false;
     }
 

translator/src/main/java/com/google/devtools/j2objc/types/Types.java

@@ -78,6 +78,7 @@ public class Types {
   private final IOSMethodBinding releaseMethod;
   private final IOSMethodBinding autoreleaseMethod;
   private final IOSMethodBinding allocMethod;
+  private final IOSMethodBinding deallocMethod;
 
   public Types(AST ast) {
     this.ast = ast;
@@ -116,6 +117,8 @@ public Types(AST ast) {
         NameTable.AUTORELEASE_METHOD, Modifier.PUBLIC, idType, NSObject);
     allocMethod = IOSMethodBinding.newMethod(
         NameTable.ALLOC_METHOD, Modifier.PUBLIC, idType, NSObject);
+    deallocMethod = IOSMethodBinding.newMethod(
+        NameTable.DEALLOC_METHOD, Modifier.PUBLIC, idType, NSObject);
   }
 
   private IOSTypeBinding mapIOSType(IOSTypeBinding type) {
@@ -332,4 +335,8 @@ public IOSMethodBinding getAutoreleaseMethod() {
   public IOSMethodBinding getAllocMethod() {
     return allocMethod;
   }
+
+  public IOSMethodBinding getDeallocMethod() {
+    return deallocMethod;
+  }
 }

translator/src/main/java/com/google/devtools/j2objc/util/BindingUtil.java

@@ -505,16 +505,6 @@ public int compare(IMemberValuePairBinding o1, IMemberValuePairBinding o2) {
     return valuePairs;
   }
 
-  /**
-   * Returns true if method is an Objective-C dealloc method.
-   */
-  public static boolean isDestructor(IMethodBinding m) {
-    String methodName = m.getName();
-    return !m.isConstructor() && !isStatic(m) && m.getParameterTypes().length == 0
-        && (methodName.equals(NameTable.FINALIZE_METHOD)
-            || methodName.equals(NameTable.DEALLOC_METHOD));
-  }
-
   /**
    * Returns the attributes of a Property annotation.
    */

translator/src/main/java/com/google/devtools/j2objc/util/NameTable.java

@@ -496,7 +496,7 @@ public static String getMethodName(IMethodBinding method) {
       return "init";
     }
     String name = method.getName();
-    if (isReservedName(name)) {
+    if (!BindingUtil.isSynthetic(method) && isReservedName(name)) {
       name += "__";
     }
     return name;
@@ -520,9 +520,6 @@ public String getMethodSelector(IMethodBinding method) {
     if (method instanceof IOSMethodBinding) {
       return ((IOSMethodBinding) method).getSelector();
     }
-    if (BindingUtil.isDestructor(method)) {
-      return DEALLOC_METHOD;
-    }
     if (method.isConstructor() || BindingUtil.isStatic(method)) {
       return selectorForOriginalBinding(method);
     }
@@ -560,8 +557,8 @@ private String selectorForOriginalBinding(IMethodBinding method) {
    * not returned by getMethodSelector().
    */
   public List<String> getExtraSelectors(IMethodBinding method) {
-    if (method instanceof IOSMethodBinding || method.isConstructor() || BindingUtil.isStatic(method)
-        || BindingUtil.isDestructor(method)) {
+    if (method instanceof IOSMethodBinding || method.isConstructor()
+        || BindingUtil.isStatic(method)) {
       return Collections.emptyList();
     }
     List<IMethodBinding> originalMethods = getOriginalMethodBindings(method);

translator/src/main/resources/com/google/devtools/j2objc/JRE.mappings

@@ -43,6 +43,7 @@ java.lang.Object.equals(Ljava/lang/Object;)Z = isEqual:
 java.lang.Object.getClass()Ljava/lang/Class; = getClass
 java.lang.Object.hashCode()I = hash
 java.lang.Object.toString()Ljava/lang/String; = description
+java.lang.Object.finalize()V = javaFinalize
 
 # java.lang.Class
 java.lang.Class.asSubclass(Ljava/lang/Class;)Ljava/lang/Class; = asSubclass: