8155106: MHs.Lookup.findConstructor returns handles for array classes
Reviewed-by: shade, sundar
--- a/jdk/src/java.base/share/classes/java/lang/invoke/MethodHandleImpl.java Wed Apr 27 18:52:32 2016 +0200
+++ b/jdk/src/java.base/share/classes/java/lang/invoke/MethodHandleImpl.java Wed Apr 27 20:18:49 2016 +0200
@@ -25,6 +25,7 @@
package java.lang.invoke;
+import java.lang.reflect.Array;
import java.security.AccessController;
import java.security.PrivilegedAction;
import java.util.Arrays;
@@ -1892,7 +1893,8 @@
MH_tryFinallyExec = 12,
MH_tryFinallyVoidExec = 13,
MH_decrementCounter = 14,
- MH_LIMIT = 15;
+ MH_Array_newInstance = 15,
+ MH_LIMIT = 16;
static MethodHandle getConstantHandle(int idx) {
MethodHandle handle = HANDLES[idx];
@@ -1965,6 +1967,9 @@
case MH_decrementCounter:
return IMPL_LOOKUP.findStatic(MethodHandleImpl.class, "decrementCounter",
MethodType.methodType(int.class, int.class));
+ case MH_Array_newInstance:
+ return IMPL_LOOKUP.findStatic(Array.class, "newInstance",
+ MethodType.methodType(Object.class, Class.class, int.class));
}
} catch (ReflectiveOperationException ex) {
throw newInternalError(ex);
--- a/jdk/src/java.base/share/classes/java/lang/invoke/MethodHandles.java Wed Apr 27 18:52:32 2016 +0200
+++ b/jdk/src/java.base/share/classes/java/lang/invoke/MethodHandles.java Wed Apr 27 20:18:49 2016 +0200
@@ -1010,6 +1010,9 @@
* @throws NullPointerException if any argument is null
*/
public MethodHandle findConstructor(Class<?> refc, MethodType type) throws NoSuchMethodException, IllegalAccessException {
+ if (refc.isArray()) {
+ throw new NoSuchMethodException("no constructor for array class: " + refc.getName());
+ }
String name = "<init>";
MemberName ctor = resolveOrFail(REF_newInvokeSpecial, refc, name, type);
return getDirectConstructor(refc, ctor);
@@ -2221,6 +2224,27 @@
}
/**
+ * Produces a method handle constructing arrays of a desired type.
+ * The return type of the method handle will be the array type.
+ * The type of its sole argument will be {@code int}, which specifies the size of the array.
+ * @param arrayClass an array type
+ * @return a method handle which can create arrays of the given type
+ * @throws NullPointerException if the argument is {@code null}
+ * @throws IllegalArgumentException if {@code arrayClass} is not an array type
+ * @see java.lang.reflect.Array#newInstance(Class, int)
+ * @since 9
+ */
+ public static
+ MethodHandle arrayConstructor(Class<?> arrayClass) throws IllegalArgumentException {
+ if (!arrayClass.isArray()) {
+ throw newIllegalArgumentException("not an array class: " + arrayClass.getName());
+ }
+ MethodHandle ani = MethodHandleImpl.getConstantHandle(MethodHandleImpl.MH_Array_newInstance).
+ bindTo(arrayClass.getComponentType());
+ return ani.asType(ani.type().changeReturnType(arrayClass));
+ }
+
+ /**
* Produces a method handle giving read access to elements of an array.
* The type of the method handle will have a return type of the array's
* element type. Its first argument will be the array type,
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/jdk/test/java/lang/invoke/ArrayConstructorTest.java Wed Apr 27 20:18:49 2016 +0200
@@ -0,0 +1,91 @@
+/*
+ * Copyright (c) 2016, 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 8155106
+ * @run testng/othervm -ea -esa test.java.lang.invoke.ArrayConstructorTest
+ */
+package test.java.lang.invoke;
+
+import java.lang.invoke.MethodHandle;
+import java.lang.invoke.MethodHandles;
+
+import static java.lang.invoke.MethodType.methodType;
+
+import static org.testng.AssertJUnit.*;
+
+import org.testng.annotations.*;
+
+
+public class ArrayConstructorTest {
+
+ static final MethodHandles.Lookup LOOKUP = MethodHandles.lookup();
+
+ @Test
+ public static void testFindConstructorArray() {
+ boolean caught = false;
+ try {
+ MethodHandle h = LOOKUP.findConstructor(Object[].class, methodType(void.class));
+ } catch (NoSuchMethodException nsme) {
+ assertEquals("no constructor for array class: [Ljava.lang.Object;", nsme.getMessage());
+ caught = true;
+ } catch (Exception e) {
+ throw new AssertionError("unexpected exception: " + e);
+ }
+ assertTrue(caught);
+ }
+
+ @DataProvider
+ static Object[][] arrayConstructorNegative() {
+ return new Object[][]{
+ {String.class, IllegalArgumentException.class, "not an array class: java.lang.String"},
+ {null, NullPointerException.class, null}
+ };
+ }
+
+ @Test(dataProvider = "arrayConstructorNegative")
+ public static void testArrayConstructorNegative(Class<?> clazz, Class<?> exceptionClass, String message) {
+ boolean caught = false;
+ try {
+ MethodHandle h = MethodHandles.arrayConstructor(clazz);
+ } catch (Exception e) {
+ assertEquals(exceptionClass, e.getClass());
+ if (message != null) {
+ assertEquals(message, e.getMessage());
+ }
+ caught = true;
+ }
+ assertTrue(caught);
+ }
+
+ @Test
+ public static void testArrayConstructor() throws Throwable {
+ MethodHandle h = MethodHandles.arrayConstructor(String[].class);
+ assertEquals(methodType(String[].class, int.class), h.type());
+ String[] a = (String[]) h.invoke(17);
+ assertEquals(17, a.length);
+ }
+
+}