8022316: Generic throws, overriding and method reference

Reviewed-by: jjg, mcimadamore

langtools/src/share/classes/com/sun/tools/javac/code/Types.java

@@ -505,12 +505,27 @@ public class Types {
 
             //merge thrown types - form the intersection of all the thrown types in
             //all the signatures in the list
+            boolean toErase = !bestSoFar.type.hasTag(FORALL);
             List<Type> thrown = null;
-            for (Symbol msym1 : methodSyms) {
-                Type mt1 = memberType(origin.type, msym1);
+            Type mt1 = memberType(origin.type, bestSoFar);
+            for (Symbol msym2 : methodSyms) {
+                Type mt2 = memberType(origin.type, msym2);
+                List<Type> thrown_mt2 = mt2.getThrownTypes();
+                if (toErase) {
+                    thrown_mt2 = erasure(thrown_mt2);
+                } else {
+                    /* If bestSoFar is generic then all the methods are generic.
+                     * The opposite is not true: a non generic method can override
+                     * a generic method (raw override) so it's safe to cast mt1 and
+                     * mt2 to ForAll.
+                     */
+                    ForAll fa1 = (ForAll)mt1;
+                    ForAll fa2 = (ForAll)mt2;
+                    thrown_mt2 = subst(thrown_mt2, fa2.tvars, fa1.tvars);
+                }
                 thrown = (thrown == null) ?
-                    mt1.getThrownTypes() :
-                    chk.intersect(mt1.getThrownTypes(), thrown);
+                    thrown_mt2 :
+                    chk.intersect(thrown_mt2, thrown);
             }
 
             final List<Type> thrown1 = thrown;

langtools/test/tools/javac/T8022316/CompilerErrorGenericThrowPlusMethodRefTest.java

@@ -0,0 +1,78 @@
+/*
+ * Copyright (c) 2013, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.  Oracle designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Oracle in the LICENSE file that accompanied this code.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+/*
+ * @test
+ * @bug 8022316
+ * @summary Generic throws, overriding and method reference
+ * @compile/fail/ref=CompilerErrorGenericThrowPlusMethodRefTest.out -XDrawDiagnostics CompilerErrorGenericThrowPlusMethodRefTest.java
+ */
+
+@SuppressWarnings("unchecked")
+public class CompilerErrorGenericThrowPlusMethodRefTest {
+    interface SAM11 {
+        public <E extends Throwable> void foo() throws E ;
+    }
+
+    interface SAM12 extends SAM11{
+        @Override
+        public void foo() throws Throwable;
+    }
+
+    public void boo() throws RuntimeException {}
+
+    static void test1() {
+        try {
+            SAM12 s2 = new CompilerErrorGenericThrowPlusMethodRefTest()::boo;
+            s2.foo();
+        } catch(Throwable ex) {}
+    }
+
+    static void test2() {
+        SAM11 s1 = null;
+        s1.<Exception>foo();
+        s1.<RuntimeException>foo();
+    }
+
+    interface SAM21 {
+        <E extends Exception> void m(E arg) throws E;
+    }
+
+    interface SAM22 {
+        <F extends Exception> void m(F arg) throws F;
+    }
+
+    interface SAM23 extends SAM21, SAM22 {}
+
+    public <E extends Exception> void bar(E e) throws E {}
+
+    static <E extends Exception> void test3(E e) {
+        try {
+            SAM23 s2 = new CompilerErrorGenericThrowPlusMethodRefTest()::bar;
+            s2.m(e);
+        } catch(Exception ex) {}
+    }
+
+}

langtools/test/tools/javac/T8022316/CompilerErrorGenericThrowPlusMethodRefTest.out

@@ -0,0 +1,2 @@
+CompilerErrorGenericThrowPlusMethodRefTest.java:55:26: compiler.err.unreported.exception.need.to.catch.or.throw: java.lang.Exception
+1 error