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) 2011, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 */
24 /*
25 * @test
26 * @bug 8003280
27 * @summary Add lambda tests
28 * basic test for simple lambda expressions in multiple scopes
29 * @author Brian Goetz
30 * @author Maurizio Cimadamore
31 * @run main LambdaExpr01
32 */
34 public class LambdaExpr01 {
36 static int assertionCount = 0;
38 static void assertTrue(boolean cond) {
39 assertionCount++;
40 if (!cond)
41 throw new AssertionError();
42 }
44 interface S_int {
45 int m();
46 }
48 interface S_Integer {
49 Integer m();
50 }
52 interface S_int_int {
53 int m(int i);
54 }
56 interface S_Integer_int {
57 int m(Integer i);
58 }
60 interface S_int_Integer {
61 Integer m(int i);
62 }
64 interface S_Integer_Integer {
65 Integer m(Integer i);
66 }
68 static {
69 S_int s_i = ()-> 3;
70 assertTrue(3 == s_i.m());
71 S_Integer s_I = ()-> 3;
72 assertTrue(3 == s_I.m());
73 S_int_int s_i_i = (int x)-> x+1;
74 assertTrue(4 == s_i_i.m(3));
75 S_int_Integer s_i_I = (int x)-> x+1;
76 assertTrue(4 == s_i_I.m(3));
77 S_Integer_int s_I_i = (Integer x) -> x.intValue() + 1;
78 assertTrue(4 == s_I_i.m(3));
79 S_Integer_Integer s_I_I = (Integer x) -> x.intValue() + 1;
80 assertTrue(4 == s_I_I.m(3));
81 }
83 {
84 S_int s_i = ()-> 3;
85 assertTrue(3 == s_i.m());
86 S_Integer s_I = ()-> 3;
87 assertTrue(3 == s_I.m());
88 S_int_int s_i_i = (int x)-> x+1;
89 assertTrue(4 == s_i_i.m(3));
90 S_int_Integer s_i_I = (int x)-> x+1;
91 assertTrue(4 == s_i_I.m(3));
92 S_Integer_int s_I_i = (Integer x) -> x.intValue() + 1;
93 assertTrue(4 == s_I_i.m(3));
94 S_Integer_Integer s_I_I = (Integer x) -> x.intValue() + 1;
95 assertTrue(4 == s_I_I.m(3));
96 }
98 static void test1() {
99 S_int s_i = ()-> 3;
100 assertTrue(3 == s_i.m());
101 S_Integer s_I = ()-> 3;
102 assertTrue(3 == s_I.m());
103 S_int_int s_i_i = (int x)-> x+1;
104 assertTrue(4 == s_i_i.m(3));
105 S_int_Integer s_i_I = (int x)-> x+1;
106 assertTrue(4 == s_i_I.m(3));
107 S_Integer_int s_I_i = (Integer x) -> x.intValue() + 1;
108 assertTrue(4 == s_I_i.m(3));
109 S_Integer_Integer s_I_I = (Integer x) -> x.intValue() + 1;
110 assertTrue(4 == s_I_I.m(3));
111 }
113 void test2() {
114 S_int s_i = ()-> 3;
115 assertTrue(3 == s_i.m());
116 S_Integer s_I = ()-> 3;
117 assertTrue(3 == s_I.m());
118 S_int_int s_i_i = (int x)-> x+1;
119 assertTrue(4 == s_i_i.m(3));
120 S_int_Integer s_i_I = (int x)-> x+1;
121 assertTrue(4 == s_i_I.m(3));
122 S_Integer_int s_I_i = (Integer x) -> x.intValue() + 1;
123 assertTrue(4 == s_I_i.m(3));
124 S_Integer_Integer s_I_I = (Integer x) -> x.intValue() + 1;
125 assertTrue(4 == s_I_I.m(3));
126 }
128 public static void main(String[] args) {
129 test1();
130 new LambdaExpr01().test2();
131 assertTrue(assertionCount == 24);
132 }
133 }