conversations-classic/src/main/java/eu/siacs/conversations/utils/SerialSingleThreadExecutor.java

51 lines
1,015 B
Java

package eu.siacs.conversations.utils;
import android.os.Looper;
import java.util.ArrayDeque;
import java.util.Queue;
import java.util.concurrent.Executor;
import java.util.concurrent.Executors;
public class SerialSingleThreadExecutor implements Executor {
final Executor executor = Executors.newSingleThreadExecutor();
protected final Queue<Runnable> tasks = new ArrayDeque();
Runnable active;
public SerialSingleThreadExecutor() {
this(false);
}
public SerialSingleThreadExecutor(boolean prepareLooper) {
if (prepareLooper) {
execute(new Runnable() {
@Override
public void run() {
Looper.prepare();
}
});
}
}
public synchronized void execute(final Runnable r) {
tasks.offer(new Runnable() {
public void run() {
try {
r.run();
} finally {
scheduleNext();
}
}
});
if (active == null) {
scheduleNext();
}
}
protected synchronized void scheduleNext() {
if ((active = tasks.poll()) != null) {
executor.execute(active);
}
}
}