infernap12/jdk
1
0
Fork 0
mirror of https://github.com/openjdk/jdk.git synced 2026-03-15 02:13:19 +00:00
Code Issues Packages Projects Releases Wiki Activity

8209824: Improve the code coverage for ThreadLocal

Browse Source 
Reviewed-by: dholmes, alanb
This commit is contained in:
Hamlin Li 2019-10-17 13:18:01 +08:00
parent 463d6e9640
commit 2a43248dba
1 changed files with 83 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

83
test/jdk/java/lang/ThreadLocal/ReplaceStaleEntry.java Normal file
View File

@ -0,0 +1,83 @@
/*
* Copyright (c) 2019, 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.
*
* 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 8209824
* @summary per latest JDK code coverage report, 2 methods replaceStaleEntry
* and prevIndex in ThreadLocal.ThreadLocalMap are not touched
* by any JDK regression tests, this is to trigger the code paths.
* @modules java.base/java.lang:+open
* @run testng ReplaceStaleEntry
*/
import java.lang.reflect.Field;
import java.util.HashMap;
import java.util.Map;
import static org.testng.Assert.assertEquals;
import org.testng.annotations.BeforeClass;
import org.testng.annotations.Test;
public class ReplaceStaleEntry {
public static int INITIAL_CAPACITY;
@BeforeClass
public static void setup() throws Exception {
Class<?> clazz = Class.forName("java.lang.ThreadLocal$ThreadLocalMap");
Field f = clazz.getDeclaredField("INITIAL_CAPACITY");
f.setAccessible(true);
INITIAL_CAPACITY = f.getInt(null);
System.out.println("INITIAL_CAPACITY: " + INITIAL_CAPACITY);
}
/**
* This test triggers the code path to replaceStaleEntry, so as prevIndex is
* triggered too as it's called by replaceStaleEntry.
* The code paths must be triggered by reusing an already used entry in the
* map's entry table. The code below
* 1. first occupies the entries
* 2. then expunges the entries by removing strong references to thread locals
* 3. then reuse some of entries by adding more thread locals to the thread
* and, the above steps are run for several times by adding more and more
* thread locals, also trigger rehash of the map.
*/
@Test
public static void test() {
Map<Integer, ThreadLocal> locals = new HashMap<>();
for (int j = 1; j < 32; j *= 2) {
int loop = INITIAL_CAPACITY * j;
for (int i = 0; i < loop; i++) {
ThreadLocal l = new ThreadLocal<Integer>();
l.set(i);
locals.put(i, l);
}
locals.keySet().stream().forEach(i -> {
assertEquals((int)locals.get(i).get(), (int)i, "Unexpected thread local value!");
});
locals.clear();
System.gc();
}
}
}