1 /* 2 * Copyright (c) 2016, 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. Oracle designates this 8 * particular file as subject to the "Classpath" exception as provided 9 * by Oracle in the LICENSE file that accompanied this code. 10 * 11 * This code is distributed in the hope that it will be useful, but WITHOUT 12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 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). 16 * 17 * You should have received a copy of the GNU General Public License version 18 * 2 along with this work; if not, write to the Free Software Foundation, 19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 20 * 21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 22 * or visit www.oracle.com if you need additional information or have any 23 * questions. 24 */ 25 26 /* @test 27 * @summary unit tests for java.lang.invoke.MethodHandles 28 * @run testng/othervm -ea -esa test.java.lang.invoke.ConstantIdentityMHTest 29 */ 30 package test.java.lang.invoke; 31 32 import java.lang.invoke.MethodHandle; 33 import java.lang.invoke.MethodHandles; 34 import java.lang.invoke.MethodType; 35 import java.util.List; 36 import static java.lang.invoke.MethodHandles.*; 37 import static java.lang.invoke.MethodType.*; 38 import static org.testng.AssertJUnit.*; 39 import org.testng.annotations.*; 40 41 public class ConstantIdentityMHTest { 42 43 @Test 44 public void testZero() throws Throwable { 45 MethodHandle mhz1 =MethodHandles.zero(void.class); 46 assertEquals("()void", mhz1.type().toString()); 47 MethodHandle mhz2 = MethodHandles.zero(int.class); 48 assertEquals("()int", mhz2.type().toString()); 49 MethodHandle mhz3 = MethodHandles.zero(Integer.class); 50 assertEquals("()Integer", mhz3.type().toString()); 51 } 52 53 @Test 54 @ExpectedExceptions(NullPointerException.class) 55 public void testZeroNPE() { 56 MethodHandle mh = MethodHandles.zero(null); 57 } 58 59 @Test 60 void testEmpty() throws Throwable { 61 MethodHandle cat = lookup().findVirtual(String.class, "concat", methodType(String.class, String.class)); 62 assertEquals("xy", (String)cat.invoke("x","y")); 63 MethodHandle mhEmpty = MethodHandles.empty(cat.type()); 64 assertEquals(null, (String)mhEmpty.invoke("x","y")); 65 } 66 67 @Test 68 @ExpectedExceptions(NullPointerException.class) 69 void testEmptyNPE() { 70 MethodHandle lenEmptyMH = MethodHandles.empty(null); 71 } 72 }