synchronized lock and separate threads: Android

Question

I have a callback function in which i receive a string. This string is to be passed to a separate thread for processing since the processing takes time. Also, since multiple callbacks can come simultaneously, I would like to have a synchronized lock till i pass the string into the new thread. But I do not wish to have the new thread (where processing is going on) to be locked also.

Could someone please help me figure out the design for this?

I have written the following code but in this I think in this no callbacks can be received till the whole processing of the separate thread is also done, thereby defeating the whole purpose of this new thread.

String sLine;
onClick(String line){
synchronized (lock) {
                sLine = line;
                new Thread(new Runnable() {
                    @Override
                    public void run() {
                    doProcessing(Sline);    

                }).start(); 
}
}

Answer 1

Also, since multiple callbacks can come simultaneously, I would like to have a synchronized lock till i pass the string into the new thread.

A: I don't think you need to put a lock here. This string is not accessed by multi-thread.

But I do not wish to have the new thread (where processing is going on) to be locked also.

A: As I see nothing was locked here :) I think it could be better if you do something like that:

• Create an class Runner implement Runnable, this class will do processing
• Everytime you got callback, use ThreadPoolExecutor to execute this Runner. This help you reuse Thread instance.
• Note that: These line code doesn't need to synchronized, put synchronized inside processing method if you need.

 

// Implement class Runner

public class Runner implements Runnable {
    private String mLine;

    public Runner(String line) {
        mLine = line;
    }

    @Override
    public void run() {
        process();
    }

    public void process() {
        // Do processing with mLine
        // Put synchronized if you need, it bases on your context
    }
}

// Initialize thread pool

private ThreadPoolExecutor executor = new ThreadPoolExecutor(10, 100, 1000, TimeUnit.SECONDS, new LinkedBlockingDeque<Runnable>());

// Execute runner when receiving callback

onClick(String s) {
        Runner runner = new Runner(s);
        executor.execute(runner);
    }

Answer 2

Try changing like below

String sLine;
onClick(final String line){
                sLine = line;
                new Thread(new Runnable() {
                    @Override
                    public void run() {
                    doProcessing(line);    

                }).start();     
}