diff options
| -rw-r--r-- | tests/features164/declareMixin/CaseEConcurrent.java | 8 | ||||
| -rw-r--r-- | weaver/src/main/java/org/aspectj/weaver/bcel/BcelTypeMunger.java | 28 |
2 files changed, 30 insertions, 6 deletions
diff --git a/tests/features164/declareMixin/CaseEConcurrent.java b/tests/features164/declareMixin/CaseEConcurrent.java index df1e13774..874f249d5 100644 --- a/tests/features164/declareMixin/CaseEConcurrent.java +++ b/tests/features164/declareMixin/CaseEConcurrent.java @@ -39,9 +39,11 @@ public class CaseEConcurrent { // the byte code, e.g. with JDK tool 'javap -v'. /* public void doSomething() { - synchronized (this) { - if (id == null) - id = "doing something"; + if (id == null) { + synchronized (this) { + if (id == null) + id = "doing something"; + } } callMe(id); } diff --git a/weaver/src/main/java/org/aspectj/weaver/bcel/BcelTypeMunger.java b/weaver/src/main/java/org/aspectj/weaver/bcel/BcelTypeMunger.java index 0ecad3606..3463d444a 100644 --- a/weaver/src/main/java/org/aspectj/weaver/bcel/BcelTypeMunger.java +++ b/weaver/src/main/java/org/aspectj/weaver/bcel/BcelTypeMunger.java @@ -1436,6 +1436,26 @@ public class BcelTypeMunger extends ConcreteTypeMunger { InstructionList body = new InstructionList(); InstructionFactory fact = gen.getFactory(); + // Create a delegate method body which basically looks as follows: + // + // public void methodOne() { + // if (this.ajc$instance$MyAspect$MyMixin == null) { + // synchronized(this) { + // if (this.ajc$instance$MyAspect$MyMixin == null) { + // this.ajc$instance$MyAspect$MyMixin = MyAspect.aspectOf().createImplementation(this); + // } + // } + // } + // this.ajc$instance$MyAspect$MyMixin.methodOne(); + // } + + // Before synchronising on 'this', perform a preliminary null check on the delegate field. Only if it is null, + // it makes sense to synchronise, then check for null again and initialise the delegate, if null. + body.append(InstructionConstants.ALOAD_0); + body.append(Utility.createGet(fact, munger.getDelegate(weaver.getLazyClassGen().getType()))); + InstructionBranch outerIfNonNull = InstructionFactory.createBranchInstruction(Constants.IFNONNULL, null); + body.append(outerIfNonNull); + // Wrap delegate field initialisation in 'synchronized(this)' block - MONITORENTER (beginning of 'try') body.append(InstructionConstants.ALOAD_0); body.append(InstructionConstants.MONITORENTER); @@ -1444,8 +1464,8 @@ public class BcelTypeMunger extends ConcreteTypeMunger { // synchronized block, see https://docs.oracle.com/javase/specs/jvms/se17/html/jvms-3.html#jvms-3.14. InstructionHandle tryStart = body.append(InstructionConstants.ALOAD_0); body.append(Utility.createGet(fact, munger.getDelegate(weaver.getLazyClassGen().getType()))); - InstructionBranch ifNonNull = InstructionFactory.createBranchInstruction(Constants.IFNONNULL, null); - body.append(ifNonNull); + InstructionBranch innerIfNonNull = InstructionFactory.createBranchInstruction(Constants.IFNONNULL, null); + body.append(innerIfNonNull); // Create and store a new instance body.append(InstructionConstants.ALOAD_0); // 'this' is where we'll store the field value @@ -1494,7 +1514,7 @@ public class BcelTypeMunger extends ConcreteTypeMunger { // Wrap delegate field initialisation in 'synchronized(this)' block - MONITOREXIT (end of 'try') InstructionHandle ifNonNullElse = body.append(InstructionConstants.ALOAD_0); - ifNonNull.setTarget(ifNonNullElse); + innerIfNonNull.setTarget(ifNonNullElse); body.append(InstructionConstants.MONITOREXIT); // There was no error in the 'synchronized(this)' block -> jump to first instruction after exception handler @@ -1519,6 +1539,8 @@ public class BcelTypeMunger extends ConcreteTypeMunger { InstructionHandle afterTryCatch = body.append(InstructionConstants.ALOAD_0); // Tell 'gotoAfterTryCatch' where to find the first statement after the exception handler gotoAfterTryCatch.setTarget(afterTryCatch); + // The outer delegate field null check should also jump to the same place, if the delegate field is not null + outerIfNonNull.setTarget(afterTryCatch); body.append(Utility.createGet(fact, munger.getDelegate(weaver.getLazyClassGen().getType()))); // args |