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/*
* 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 8164102
* @run main/othervm -ea -esa test.java.lang.invoke.CountedLoopIterationCountsTest
*/
package test.java.lang.invoke;
import java.lang.invoke.MethodHandle;
import java.lang.invoke.MethodHandles;
import java.lang.invoke.MethodType;
public class CountedLoopIterationCountsTest {
public static void main(String[] args) throws Throwable {
run(1, -10, 0);
run(1, 0, 0);
run(Integer.MAX_VALUE - 1, Integer.MIN_VALUE + 10, 0);
run(Integer.MIN_VALUE, Integer.MIN_VALUE + 4, 4);
run(Integer.MAX_VALUE - 2, Integer.MAX_VALUE - 1, 1);
run(Integer.MAX_VALUE - 1, 0, 0);
run(Integer.MAX_VALUE - 1, 10, 0);
run(Integer.MAX_VALUE - 1, -10, 0);
run(Integer.MAX_VALUE, Integer.MIN_VALUE + 10, 0);
run(Integer.MAX_VALUE - 1, Integer.MAX_VALUE, 1);
run(Integer.MAX_VALUE, Integer.MAX_VALUE, 0);
if (failed) {
throw new AssertionError("one or more tests failed");
}
}
static boolean failed = false;
private static void run(int start, int end, int expectedIterations) throws Throwable {
System.out.println("run from " + start + " to " + end);
MethodHandle loop = MethodHandles.countedLoop(
MethodHandles.constant(int.class, start), // iterate from given start (inclusive) ...
MethodHandles.constant(int.class, end), // ... to given end (exclusive)
MH_m1, // initialise loop variable to -1
MH_step); // increment loop counter by one in each iteration
// The loop variable's value, and hence the loop result, will be "number of iterations" minus one.
int r = (int) loop.invoke();
if (r + 1 != expectedIterations) {
System.out.println("expected " + expectedIterations + " iterations, but got " + r);
failed = true;
}
}
static int step(int stepCount, int counter) {
return stepCount + 1;
}
static final MethodHandle MH_m1;
static final MethodHandle MH_step;
static {
try {
MH_m1 = MethodHandles.constant(int.class, -1);
MH_step = MethodHandles.lookup().findStatic(CountedLoopIterationCountsTest.class, "step",
MethodType.methodType(int.class, int.class, int.class));
} catch (Throwable t) {
throw new ExceptionInInitializerError(t);
}
}
}
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