Qt中QTcpServer多线程误区
2015-08-12 17:24
197 查看
这几天在写基于tcp 的文件传输,用到了QTcpServer 这个类,大家都知道如果想用多线程处理接入的连接套接字(QTcpSocket ), 需要自己重新定义一个基类为QTcpServer 的派生类,并且重新实现其中的虚函数 incomingConnection() 去接受client 连接,
并创建线程处理该连接。
假设 class FortuneThread :public QThread 是处理client 连接的子线程, 在该线程里向client 端写入数据,问题出来了...
假设类的定义是这样的:
[cpp] view plaincopy
//第一种情况:
//声明:
class FortuneThread : public QThread
{
Q_OBJECT
public :
explicit FortuneThread ( QObject * parent = 0 );
explicit FortuneThread ( QObject * parent, int socketDescriptor);
private :
int socketDescriptor;
QTcpSocket clientConnection;
//...... ..
}
//定义:
FortuneThread::FortuneThread(QObject* parent , int socketDescriptor):QThread ( parent)
{
clientConnection. setSocketDescriptor( socketDescriptor);
}
//第二种情况:
//声明:
class FortuneThread : public QThread
{
Q_OBJECT
public :
explicit FortuneThread ( QObject * parent = 0 );
explicit FortuneThread ( QObject * parent, int socketDescriptor);
private :
int socketDescriptor;
QTcpSocket * clientConnection;
//........
}
//定义:
FortuneThread :: FortuneThread ( QObject * parent, int socketDescriptor):QThread ( parent)
{
clientConnection = new QTcpSocket ; clientConnection-> setSocketDescriptor( socketDescriptor);
}
//第三种情况:
//声明:
class FortuneThread : public QThread
{
Q_OBJECT
public :
explicit FortuneThread ( QObject * parent = 0 );
explicit FortuneThread ( QObject * parent, int socketDescriptor);
private :
int socketDescriptor;
QTcpSocket * clientConnection;
//........
}
定义:
FortuneThread :: FortuneThread ( QObject * parent, int socketDescriptor):
QThread ( parent)
{
this -> socketDescriptor = socketDescriptor;
}
void
FortuneThread ::run(
{
clientConnection = new QTcpSocket ;
clientConnection -> setSocketDescriptor(socketDescriptor);
}
并创建线程处理该连接。
假设 class FortuneThread :public QThread 是处理client 连接的子线程, 在该线程里向client 端写入数据,问题出来了...
假设类的定义是这样的:
[cpp] view plaincopy
//第一种情况:
//声明:
class FortuneThread : public QThread
{
Q_OBJECT
public :
explicit FortuneThread ( QObject * parent = 0 );
explicit FortuneThread ( QObject * parent, int socketDescriptor);
private :
int socketDescriptor;
QTcpSocket clientConnection;
//...... ..
}
//定义:
FortuneThread::FortuneThread(QObject* parent , int socketDescriptor):QThread ( parent)
{
clientConnection. setSocketDescriptor( socketDescriptor);
}
//第二种情况:
//声明:
class FortuneThread : public QThread
{
Q_OBJECT
public :
explicit FortuneThread ( QObject * parent = 0 );
explicit FortuneThread ( QObject * parent, int socketDescriptor);
private :
int socketDescriptor;
QTcpSocket * clientConnection;
//........
}
//定义:
FortuneThread :: FortuneThread ( QObject * parent, int socketDescriptor):QThread ( parent)
{
clientConnection = new QTcpSocket ; clientConnection-> setSocketDescriptor( socketDescriptor);
}
//第三种情况:
//声明:
class FortuneThread : public QThread
{
Q_OBJECT
public :
explicit FortuneThread ( QObject * parent = 0 );
explicit FortuneThread ( QObject * parent, int socketDescriptor);
private :
int socketDescriptor;
QTcpSocket * clientConnection;
//........
}
定义:
FortuneThread :: FortuneThread ( QObject * parent, int socketDescriptor):
QThread ( parent)
{
this -> socketDescriptor = socketDescriptor;
}
void
FortuneThread ::run(
{
clientConnection = new QTcpSocket ;
clientConnection -> setSocketDescriptor(socketDescriptor);
}
三种情况的区别想清楚了么? 对于前两种clientConnection的创建和管理都是属于主线程的,而你的子线程只是访问clientConnection,这时Qt会报出那个经典的错误“不允许多个线程共同访问一个QTcpSocket对象“,原话我忘记了,反正就是这个意思。 只有第三种方式才是正确的....
相关文章推荐
- Http下载图片
- HTTP协议--状态码
- Socket编程UDP/TCP
- java TCP/UDP编程
- 深度学习(卷积神经网络)一些问题总结
- spring基础:Http请求报文
- 利用xp_cmdshell 导出文件到本地和网络路径。
- linux 网络配置 修改DNS 重启被覆盖
- nginxhttp://www.nginx.cn/2181.html
- 学习JAVA不可不知的一些网络资源
- iOS项目开发实战——通过Http Post方式与服务器通信
- poj 1273 Drainage Ditches(网络流模版题)
- TCP/IP传输层,你懂多少?
- Java基础11——网络编程
- UNIX网络编程1 理解同步、阻塞、非阻塞、异步网络I/O
- Linux系统排查4——网络篇
- IBM HTTP Server https configuration
- http状态码详解
- 学习python自动化运维之输入IP或网段,返回网络.掩码等信息
- 如何让 Git 使用 HTTP 代理服务器