8009138: javac, equals-hashCode warning tuning

Reviewed-by: mcimadamore

langtools/test/tools/javac/6563143/EqualsHashCodeWarningTest.java

@@ -0,0 +1,71 @@
+/*
+ * @test /nodynamiccopyright/
+ * @bug 6563143 8008436 8009138
+ * @summary javac should issue a warning for overriding equals without hashCode
+ * @summary javac should not issue a warning for overriding equals without hasCode
+ * @summary javac, equals-hashCode warning tuning
+ * if hashCode has been overriden by a superclass
+ * @compile/ref=EqualsHashCodeWarningTest.out -Xlint:overrides -XDrawDiagnostics EqualsHashCodeWarningTest.java
+ */
+
+import java.util.Comparator;
+
+public class EqualsHashCodeWarningTest {
+    @Override
+    public boolean equals(Object o) {
+        return o == this;
+    }
+
+    @Override
+    public int hashCode() {
+        return 0;
+    }
+
+    public Comparator m() {
+        return new Comparator() {
+            @Override
+            public boolean equals(Object o) {return true;}
+
+            @Override
+            public int compare(Object o1, Object o2) {
+                return 0;
+            }
+        };
+    }
+}
+
+class SubClass extends EqualsHashCodeWarningTest {
+    @Override
+    public boolean equals(Object o) {
+        return true;
+    }
+}
+
+@SuppressWarnings("overrides")
+class DontWarnMe {
+    @Override
+    public boolean equals(Object o) {
+        return true;
+    }
+}
+
+class DoWarnMe {
+    @Override
+    public boolean equals(Object o) {
+        return o == this;
+    }
+}
+
+abstract class IamAbstractGetMeOutOfHere {
+    public boolean equals(Object o){return true;}
+}
+
+interface I {
+    public boolean equals(Object o);
+}
+
+enum E {
+    A, B
+}
+
+@interface anno {}