103 lines
3.9 KiB
Java
103 lines
3.9 KiB
Java
package com.tofvesson.async;
|
|
|
|
import com.tofvesson.collections.Pair;
|
|
|
|
import java.lang.reflect.Field;
|
|
import java.lang.reflect.Method;
|
|
import java.util.*;
|
|
import java.util.concurrent.ArrayBlockingQueue;
|
|
|
|
/**
|
|
* A thread tasked with accepting multiple instructions. This is useful for people who don't want to constantly create new threads for heavy work.
|
|
* Also good if the fields in an object instantiated in this thread aren't volatile.
|
|
*/
|
|
public class WorkerThread extends Thread {
|
|
|
|
List<Long> ids = new ArrayList<Long>();
|
|
volatile Queue<Pair<Long, Pair<Method, Pair<Object, Object>>>> queue;
|
|
volatile Map<Long, Object> output = new HashMap<Long, Object>();
|
|
volatile boolean alive=true, completed=false;
|
|
|
|
/**
|
|
* Create a WorkerThread.
|
|
* @param queueSize Maximum amount of instructions to be queued.
|
|
*/
|
|
public WorkerThread(int queueSize){
|
|
super();
|
|
try{
|
|
Field f = Thread.class.getDeclaredField("target");
|
|
f.setAccessible(true);
|
|
f.set(this, new Runnable()
|
|
{
|
|
public void run(){
|
|
synchronized (Thread.currentThread()) {
|
|
while (alive) {
|
|
if (queue.size() != 0) {
|
|
Pair<Long, Pair<Method, Pair<Object, Object>>> q = queue.poll();
|
|
Pair<Method, Pair<Object, Object>> instr = q.getValue();
|
|
try {
|
|
output.put(q.getKey(), instr.getKey().invoke(instr.getValue().getKey(), (Object[]) instr.getValue().getValue()));
|
|
completed = true;
|
|
} catch (Exception e) {
|
|
e.printStackTrace();
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
});
|
|
}catch(Exception e){}
|
|
queue = new ArrayBlockingQueue<Pair<Long, Pair<Method, Pair<Object, Object>>>>(queueSize);
|
|
}
|
|
|
|
/**
|
|
* Add a new instruction for the worker thread.
|
|
* @param invokeOn Object to invoke method on.
|
|
* @param m Method to invoke.
|
|
* @param params Parameters for method.
|
|
* @return A UID corresponding to the queued instruction.
|
|
*/
|
|
public long push(Object invokeOn, Method m, Object... params){
|
|
m.setAccessible(true);
|
|
long id;
|
|
Random r = new Random();
|
|
do{ id = r.nextLong(); }while(ids.contains(id));
|
|
queue.add(new Pair<Long, Pair<Method, Pair<Object, Object>>>(id, new Pair<Method, Pair<Object, Object>>(m, new Pair<Object, Object>(invokeOn, params))));
|
|
ids.add(id);
|
|
return id;
|
|
}
|
|
|
|
/**
|
|
* Waits for instruction to be processed and return value to be acquired.
|
|
* @param id UID of the supplied instruction.
|
|
* @return Return value from instruction called in worker thread.
|
|
*/
|
|
public Object pop(long id){
|
|
if(!ids.contains(id)) return null;
|
|
if(Thread.currentThread() == this) throw new RuntimeException("Attempting to await result in worker thread! This causes the thread to lock.");
|
|
//noinspection StatementWithEmptyBody
|
|
while(!output.containsKey(id)) ; // Block caller thread until result is received
|
|
Object o = output.get(id);
|
|
output.remove(id);
|
|
ids.remove(id);
|
|
return o;
|
|
}
|
|
|
|
/**
|
|
* Waits for current method invocation to finish before stopping thread.
|
|
*/
|
|
public void stopGraceful(){
|
|
alive = false;
|
|
}
|
|
|
|
/**
|
|
* Interrupts thread to kill it. NOTE: This method is unsafe and could cause issues if it is performing an I/O operation.
|
|
* Only call this if you are 100% sure that it won't break something or if are ready to deal with the consequences.
|
|
*/
|
|
public void stopForced(){
|
|
alive = false;
|
|
//noinspection deprecation
|
|
stop();
|
|
}
|
|
}
|