在这里作为答案给出的许多Swing片段中,主要方法是调用
SwingUtilities#invokeLater:
public class MyOneClassUiApp {
private constructUi() {
// Some Ui related Code
}
public static void main(String[] args) {
SwingUtilities.invokelater(new Runnable() {
public void run() {
new MyOneClassUiApp().constructUi();
}
});
}
}
但是根据Threads and Swing article,从主线程构建UI是安全的:
A few methods are thread-safe: In the Swing API documentation,
thread-safe methods are marked with this text:This method is thread safe,although most Swing methods are not.
An application’s GUI can often be constructed and shown in the main
thread: The following typical code is safe,as long as no components
(Swing or otherwise) have been realized:
public class MyApplication {
public static void main(String[] args) {
JFrame f = new JFrame("Labels");
// Add components to
// the frame here...
f.pack();
f.show();
// Don't do any more GUI work here...
}
}
那么,是否有一个真正的(线程安全)的原因,通过SwingUtilities#invokeLater主要构建UI,或者这只是一个习惯,记得在其他情况下做吗?
解决方法
“Swing单线程规则:Swing组件和型号只能从事件调度线程创建,修改和查询.” –
Java Concurrency in Practice,还讨论了
here和
here.如果不遵守此规则,那么您可以不可靠地构造,修改或查询任何可能假设您遵循规则的组件或模型.程序似乎可以正常工作,只能在不同的环境中神秘地失败.