在Java中从单独的线程中的ArrayList中删除项目

Question

I have a long running loop.

Inside the loop I have another loop to iterate (using iterator) on a arrayList.

If a condition is met while looping through array list I initiate a thread while passing it the current array list item and also the current iterator.

Some example code:

List<Test> testList = Collections.synchronizedList(new ArrayList<Test>());

//scanTests in a thread
while(scanTests) {
    for(Iterator<Test> itr = this.testList.iterator(); itr.hasNext();) {
        Test test = itr.next();
        if (test.closed == true && !test.inUpdateThread) {
            test.inUpdateThread = true;
            UpdateThread urt = new UpdateThread(test, itr);
            new Thread(urt).start();
        }
    }
}

//scanSomethingElse is in another thread
while (scanSomethingElse) {
    //manipulating testList 
}

If a condition is met in the UpdateThread , I want to remove the item from the testList like so:

this.itr.remove();

I have another long running loop (in another separate thread) concurrently and its doing similar types of processing on the array List (read, write etc...).

My question is if in this other loop I'm iterating the testList will this reflect the changes from the other loop?

(In case you're wondering why I'm using thread for sync, this is for remote resource and database interaction, and I need this loop to be constant and instantaneous without wait time).

Answer 1

Why don't you use something like:

while (true) {
    for (int i = 0;i < testList.size(); i++) {
        Test test = testList.get(i);
        if (test.closed == true && !test.inUpdateThread) {
            test.inUpdateThread = true;
            UpdateThread urt = new UpdateThread(some other constructor here);
            new Thread(urt).start();
        }; 

    };
};

//the UpdateThread class has a consructor UpdateThread(Test test, Iterator itr). so just modify it for fitting this example, or post it i think ki can do it for you.