7020043: Project Coin: diamond allowed on non-generic type

Summary: Diamond oerator should be disallowed on non-generic class types (i.e. String)
Reviewed-by: jjg

src/share/classes/com/sun/tools/javac/comp/Attr.java

@@ -1584,6 +1584,11 @@ public class Attr extends JCTree.Visitor {
         if (!TreeInfo.isDiamond(tree)) {
             clazztype = chk.checkClassType(
                 tree.clazz.pos(), clazztype, true);
+        } else if (!clazztype.isErroneous() &&
+                !clazztype.tsym.type.isParameterized()) {
+            log.error(tree.clazz.pos(),
+                    "cant.apply.diamond.1",
+                    clazztype, diags.fragment("diamond.non.generic", clazztype));
         }
         chk.validate(clazz, localEnv);
         if (tree.encl != null) {
@@ -1609,7 +1614,7 @@ public class Attr extends JCTree.Visitor {
         List<Type> argtypes = attribArgs(tree.args, localEnv);
         List<Type> typeargtypes = attribTypes(tree.typeargs, localEnv);
 
-        if (TreeInfo.isDiamond(tree)) {
+        if (TreeInfo.isDiamond(tree) && clazztype.tsym.type.isParameterized()) {
             clazztype = attribDiamond(localEnv, tree, clazztype, mapping, argtypes, typeargtypes);
             clazz.type = clazztype;
         } else if (allowDiamondFinder &&

src/share/classes/com/sun/tools/javac/resources/compiler.properties

@@ -1584,6 +1584,10 @@ compiler.misc.inferred.do.not.conform.to.bounds=\
 compiler.misc.diamond=\
     {0}<>
 
+# 0: type
+compiler.misc.diamond.non.generic=\
+    cannot use ''<>'' with non-generic class {0}
+
 # 0: list of type, 1: message segment
 compiler.misc.diamond.invalid.arg=\
     type argument {0} inferred for {1} is not allowed in this context

test/tools/javac/generics/diamond/neg/Neg12.java

+/*
+ * @test /nodynamiccopyright/
+ * @bug 7020043
+ *
+ * @summary  Project Coin: diamond allowed on non-generic type
+ * @author Rémi Forax
+ * @compile/fail/ref=Neg12.out Neg12.java -XDrawDiagnostics
+ *
+ */
+
+class DiamondRaw {
+   public static void main(String[] args) {
+     String s = new String<>("foo");
+   }
+}

test/tools/javac/generics/diamond/neg/Neg12.out

+Neg12.java:13:27: compiler.err.cant.apply.diamond.1: java.lang.String, (compiler.misc.diamond.non.generic: java.lang.String)
+1 error