multithreading

问题 Reading the Java 8 documentation about the java.util.concurrent.locks.Condition interface, the following example is given: class BoundedBuffer { final Lock lock = new ReentrantLock(); final Condition notFull = lock.newCondition(); final Condition notEmpty = lock.newCondition(); final Object[] items = new Object[100]; int putptr, takeptr, count; public void put(Object x) throws InterruptedException { lock.lock(); try { while (count == items.length) notFull.await(); items[putptr] = x; if (+

问题 Reading the Java 8 documentation about the java.util.concurrent.locks.Condition interface, the following example is given: class BoundedBuffer { final Lock lock = new ReentrantLock(); final Condition notFull = lock.newCondition(); final Condition notEmpty = lock.newCondition(); final Object[] items = new Object[100]; int putptr, takeptr, count; public void put(Object x) throws InterruptedException { lock.lock(); try { while (count == items.length) notFull.await(); items[putptr] = x; if (+

问题 Personal knowlegedment: I read from javacodegeeks: "... SimpleAsyncTaskExecutor is ok for toy projects but for anything larger than that it’s a bit risky since it does not limit concurrent threads and does not reuse threads. So to be safe, we will also add a task executor bean... " and from baeldung a very simple example how to add our own Task Executor. But I can find any guidance explaining what are the consequences and some worth cases to apply it. Personal desire: I am working hard to

问题 Personal knowlegedment: I read from javacodegeeks: "... SimpleAsyncTaskExecutor is ok for toy projects but for anything larger than that it’s a bit risky since it does not limit concurrent threads and does not reuse threads. So to be safe, we will also add a task executor bean... " and from baeldung a very simple example how to add our own Task Executor. But I can find any guidance explaining what are the consequences and some worth cases to apply it. Personal desire: I am working hard to

问题 I am trying to display log messages from a work thread in a GUI. I am trying to follow redirect qDebug to QTextEdit It started to work fine, but I am stuck, how to program QObject::connect(otherThread, SIGNAL(debug(QString)), s_textEdit, SLOT(append(QString)), Qt::QueuedConnection); The principle I see, that one signal in the thread shall be connected to a slot in the GUI thread; but how to trigger that signal? Also, I make some logging with QDebug , but also some output to std::cerr . Can I

问题 I am trying to display log messages from a work thread in a GUI. I am trying to follow redirect qDebug to QTextEdit It started to work fine, but I am stuck, how to program QObject::connect(otherThread, SIGNAL(debug(QString)), s_textEdit, SLOT(append(QString)), Qt::QueuedConnection); The principle I see, that one signal in the thread shall be connected to a slot in the GUI thread; but how to trigger that signal? Also, I make some logging with QDebug , but also some output to std::cerr . Can I

问题 I am trying to display log messages from a work thread in a GUI. I am trying to follow redirect qDebug to QTextEdit It started to work fine, but I am stuck, how to program QObject::connect(otherThread, SIGNAL(debug(QString)), s_textEdit, SLOT(append(QString)), Qt::QueuedConnection); The principle I see, that one signal in the thread shall be connected to a slot in the GUI thread; but how to trigger that signal? Also, I make some logging with QDebug , but also some output to std::cerr . Can I

问题 I am trying to display log messages from a work thread in a GUI. I am trying to follow redirect qDebug to QTextEdit It started to work fine, but I am stuck, how to program QObject::connect(otherThread, SIGNAL(debug(QString)), s_textEdit, SLOT(append(QString)), Qt::QueuedConnection); The principle I see, that one signal in the thread shall be connected to a slot in the GUI thread; but how to trigger that signal? Also, I make some logging with QDebug , but also some output to std::cerr . Can I

问题 I am trying to understand the below implementation of thread pool using the pthreads. When I comment out the the for loop in the main, the program stucks, upon putting the logs it seems that its getting stuck in the join function in threadpool destructor. I am unable to understand why this is happening, is there any deadlock scenario happening ? This may be naive but can someone help me understand why this is happening and how to correct this. Thanks a lot !!! #include <stdio.h> #include

问题 Frown as much as you want, I'm going to do it anyway :) My question is: in the following code, what is the proper way to handle the termination of the std::thread in the subprocess generated by fork() ? std::thread::detach() or std::thread::join() ? #include <thread> #include <iostream> #include <unistd.h> struct A { void Fork() { std::thread t(&A::Parallel, this); pid_t pid = fork(); if(pid) { //parent t.join(); } else { //child t.join(); // OR t.detach()? } } void Parallel() { std::cout <<