Tue, 14 May 2013 11:11:09 -0700
8012556: Implement lambda methods on interfaces as static
8006140: Javac NPE compiling Lambda expression on initialization expression of static field in interface
Summary: Lambdas occurring in static contexts or those not needing instance information should be generated into static methods. This has long been the case for classes. However, as a work-around to the lack of support for statics on interfaces, interface lambda methods have been generated into default methods. For lambdas in interface static contexts (fields and static methods) this causes an NPE in javac because there is no 'this'. MethodHandles now support static methods on interfaces. This changeset allows lambda methods to be generated as static interface methods. An existing bug in Hotspot (8013875) is exposed in a test when the "-esa" flag is used. This test and another test that already exposed this bug have been marked with @ignore.
Reviewed-by: mcimadamore
1 /*
2 * Copyright (c) 2012, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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10 *
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13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
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20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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24 */
26 /**
27 * @test
28 * @bug 8003639
29 * @summary convert lambda testng tests to jtreg and add them
30 * @run testng MethodReferenceTestFDCCE
31 */
33 import org.testng.annotations.Test;
34 import java.lang.reflect.Array;
36 import static org.testng.Assert.assertEquals;
37 import static org.testng.Assert.assertTrue;
38 import static org.testng.Assert.fail;
40 /**
41 * Method references and raw types.
42 * @author Robert Field
43 */
45 @Test
46 @SuppressWarnings({"rawtypes", "unchecked"})
47 public class MethodReferenceTestFDCCE {
49 static void assertCCE(Throwable t) {
50 assertEquals(t.getClass().getName(), "java.lang.ClassCastException");
51 }
53 interface Pred<T> { boolean accept(T x); }
55 interface Ps { boolean accept(short x); }
57 interface Oo { Object too(int x); }
59 interface Reto<T> { T m(); }
61 class A {}
62 class B extends A {}
64 static boolean isMinor(int x) {
65 return x < 18;
66 }
68 static boolean tst(A x) {
69 return true;
70 }
72 static Object otst(Object x) {
73 return x;
74 }
76 static boolean stst(Short x) {
77 return x < 18;
78 }
80 static short ritst() {
81 return 123;
82 }
84 public void testMethodReferenceFDPrim1() {
85 Pred<Byte> p = MethodReferenceTestFDCCE::isMinor;
86 Pred p2 = p;
87 assertTrue(p2.accept((Byte)(byte)15));
88 }
90 public void testMethodReferenceFDPrim2() {
91 Pred<Byte> p = MethodReferenceTestFDCCE::isMinor;
92 Pred p2 = p;
93 assertTrue(p2.accept((byte)15));
94 }
96 public void testMethodReferenceFDPrimICCE() {
97 Pred<Byte> p = MethodReferenceTestFDCCE::isMinor;
98 Pred p2 = p;
99 try {
100 p2.accept(15); // should throw CCE
101 fail("Exception should have been thrown");
102 } catch (Throwable t) {
103 assertCCE(t);
104 }
105 }
107 public void testMethodReferenceFDPrimOCCE() {
108 Pred<Byte> p = MethodReferenceTestFDCCE::isMinor;
109 Pred p2 = p;
110 try {
111 p2.accept(new Object()); // should throw CCE
112 fail("Exception should have been thrown");
113 } catch (Throwable t) {
114 assertCCE(t);
115 }
116 }
118 public void testMethodReferenceFDRef() {
119 Pred<B> p = MethodReferenceTestFDCCE::tst;
120 Pred p2 = p;
121 assertTrue(p2.accept(new B()));
122 }
124 public void testMethodReferenceFDRefCCE() {
125 Pred<B> p = MethodReferenceTestFDCCE::tst;
126 Pred p2 = p;
127 try {
128 p2.accept(new A()); // should throw CCE
129 fail("Exception should have been thrown");
130 } catch (Throwable t) {
131 assertCCE(t);
132 }
133 }
135 public void testMethodReferenceFDPrimPrim() {
136 Ps p = MethodReferenceTestFDCCE::isMinor;
137 assertTrue(p.accept((byte)15));
138 }
140 public void testMethodReferenceFDPrimBoxed() {
141 Ps p = MethodReferenceTestFDCCE::stst;
142 assertTrue(p.accept((byte)15));
143 }
145 public void testMethodReferenceFDPrimRef() {
146 Oo p = MethodReferenceTestFDCCE::otst;
147 assertEquals(p.too(15).getClass().getName(), "java.lang.Integer");
148 }
150 public void testMethodReferenceFDRet1() {
151 Reto<Short> p = MethodReferenceTestFDCCE::ritst;
152 assertEquals(p.m(), (Short)(short)123);
153 }
154 }