Apache Tomcat says many times:
The web application [/MyServlet] appears to have started a thread named [pool-61-thread-2] but has failed to stop it. This is very likely to create a memory leak.
Is this dangerous? The servlet should be able to handle 10.000requests/day. How to close the threads when they have finished?
class Worker {
private final CountDownLatch startSignal;
private final CountDownLatch doneSignal;
private final int threadNumber;
Worker(
CountDownLatch startSignal,
CountDownLatch doneSignal,
int threadNumber
){
this.startSignal = startSignal;
this.doneSignal = doneSignal;
this.threadNumber = threadNumber;
}
public String[][] getSomeStrArrArr() {
String[][] isRs = new String[8][20];
String[][] inRs = new String[8][20];
String[][] iwRs = new String[8][20];
try {
startSignal.await();
if (threadNumber == 1) {
// get String[][] result for thread number 1
isRs = getIS(erg1, erg2, request);
}
if (threadNumber == 2) {
// get String[][] result for thread number 2
inRs = getIN(search_plz, request);
}
if (threadNumber == 3) {
// get String[][] result for thread number 3
iwRs = getIW(erg1, erg2, request);
}
doneSignal.countDown();
} catch (InterruptedException ex) {
System.out.println(
"Thread number "+threadNumber+" has been interrupted."
);
}
if (threadNumber == 1) {
return isRs;
}
if (threadNumber == 2) {
return inRs;
}
if (threadNumber == 3) {
return iwRs;
}
return null;
}
public Callable<String[][]> getSomeCallableStrArrArr(){
return new Callable<String[][]>() {
public String[][] call() throws Exception {
return getSomeStrArrArr();
}
};
}
}
ExecutorService pool = Executors.newFixedThreadPool(3);
Set<Future<String[][]>> set = new HashSet<Future<String[][]>>();
CountDownLatch startSignal = new CountDownLatch(1);
CountDownLatch doneSignal = new CountDownLatch(3);
for (int i=1;i<=3;i++) {
Worker worker = new Worker(startSignal,doneSignal,i);
Callable<String[][]> callable =
worker.getSomeCallableStrArrArr();
Future<String[][]> future = pool.submit(callable);
set.add(future);
}
startSignal.countDown();
try {
doneSignal.await();
