8032377: test/java/lang/management/ThreadMXBean/ThreadBlockedCount.java still fails intermittently
Reviewed-by: dholmes
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*
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* version 2 for more details (a copy is included in the LICENSE file that
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* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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*/
/**
* @test
* @bug 8014477
* @summary test String.contentEquals(StringBuffer)
*/
public class StringContentEqualsBug {
static abstract class Task extends Thread {
volatile StringBuffer sb;
volatile Exception exception;
Task(StringBuffer sb) {
this.sb = sb;
}
@Override
public void run() {
try {
StringBuffer sb;
while ((sb = this.sb) != null) {
doWith(sb);
}
}
catch (Exception e) {
exception = e;
}
}
protected abstract void doWith(StringBuffer sb);
}
static class Tester extends Task {
Tester(StringBuffer sb) {
super(sb);
}
@Override
protected void doWith(StringBuffer sb) {
"AA".contentEquals(sb);
}
}
static class Disturber extends Task {
Disturber(StringBuffer sb) {
super(sb);
}
@Override
protected void doWith(StringBuffer sb) {
sb.setLength(0);
sb.trimToSize();
sb.append("AA");
}
}
public static void main(String[] args) throws Exception {
StringBuffer sb = new StringBuffer();
Task[] tasks = new Task[3];
(tasks[0] = new Tester(sb)).start();
for (int i = 1; i < tasks.length; i++) {
(tasks[i] = new Disturber(sb)).start();
}
try
{
// wait at most 5 seconds for any of the threads to throw exception
for (int i = 0; i < 20; i++) {
for (Task task : tasks) {
if (task.exception != null) {
throw task.exception;
}
}
Thread.sleep(250L);
}
}
finally {
for (Task task : tasks) {
task.sb = null;
task.join();
}
}
}
}