Fix MethodReturnCheck Ex thrown

Author: JuditKnoll

spotbugs-tests/src/test/java/edu/umd/cs/findbugs/detect/Issue2547Test.java

@@ -21,10 +21,9 @@ void testIssue() {
                 "ghIssues/issue2547/MyEx.class",
                 "ghIssues/issue2547/ExceptionFactory.class");
 
-        assertBug(3);
+        assertBug(2);
         assertBug("notThrowingExCtor", 15);
         assertBug("notThrowingExCtorCaller", 26);
-        assertBug("notThrowingExCtorCallerOutside", 37);
     }
 
     private void assertBug(int num) {

spotbugs/src/main/java/edu/umd/cs/findbugs/detect/MethodReturnCheck.java

@@ -317,11 +317,10 @@ private void sawMethodCallWithIgnoredReturnValue() {
                 SignatureParser methodSigParser = new SignatureParser(methodDescriptor.getSignature());
                 String returnTypeSig = methodSigParser.getReturnTypeSignature();
                 String returnType = ClassName.fromFieldSignature(returnTypeSig);
+                String mContainerClass = methodDescriptor.getClassDescriptor().getClassName();
                 if (returnType != null
                         && Subtypes2.instanceOf(ClassName.toDottedClassName(returnType), Values.DOTTED_JAVA_LANG_THROWABLE)
-                        && !("initCause".equals(methodDescriptor.getName()) && methodSigParser.getArguments().length == 1
-                                && "Ljava/lang/Throwable;".equals(methodSigParser.getArguments()[0]))
-                        && !("getCause".equals(methodDescriptor.getName()) && methodSigParser.getArguments().length == 0)) {
+                        && methodDescriptor.isStatic() && (returnType.equals(mContainerClass))) {
                     BugInstance warning = new BugInstance(this, "RV_EXCEPTION_NOT_THROWN", 1).addClassAndMethod(this).addMethod(callSeen)
                             .describe(MethodAnnotation.METHOD_CALLED);
                     bugAccumulator.accumulateBug(warning, SourceLineAnnotation.fromVisitedInstruction(this, callPC));

spotbugsTestCases/src/java/ghIssues/issue2547/Issue2547.java

@@ -32,7 +32,8 @@ public void createAndThrowExCtorCaller() throws MyEx {
         throw e;
     }
 
-    // non-compliant
+    // This could be non-compliant, but it's a false negative currently.
+    // It needs a good heuristic to not cause too many FPs.
     public void notThrowingExCtorCallerOutside() {
         ExceptionFactory.createMyException(5);
     }