SecurityManager类的checkAwtEventQueueAccess()方法 (SecurityManager Class checkAwtEventQueueAccess() method)

• checkAwtEventQueueAccess() method is available in java.lang package.

  checkAwtEventQueueAccess()方法在java.lang包中可用。

• checkAwtEventQueueAccess() method is used to access AWT(Abstract Window Toolkit) event queue by calling checkPermission with AWTPermission(“accessEventQueue”).

  通过使用带有AWTPermission(“ accessEventQueue”)的checkPermission来调用checkAwtEventQueueAccess()方法来访问AWT(抽象窗口工具包)事件队列。

• checkAwtEventQueueAccess() method is a non-static method, it is accessible with the class object only and if we try to access the method with the class name then we will get an error.

  checkAwtEventQueueAccess()方法是一种非静态方法，只能通过类对象访问，如果尝试使用类名称访问该方法，则会收到错误消息。

• checkAwtEventQueueAccess() method may throw an exception at the time of accessing the AWT event queue.

  在访问AWT事件队列时， checkAwtEventQueueAccess()方法可能会引发异常。

  SecurityException – This exception may throw when the calling thread is not allowed to access the AWT event queue.

  SecurityException-如果不允许调用线程访问AWT事件队列，则可能引发此异常。

Syntax:

句法：

    public void checkAwtEventQueueAccess();

Parameter(s):

参数：

• It does not accept any parameter.

  它不接受任何参数。

Return value:

返回值：

The return type of this method is void, it returns nothing.

此方法的返回类型为void ，不返回任何内容。

Example:

例：

// Java program to demonstrate the example 
// of void checkAwtEventQueueAccess()
// method of SecurityManager 
public class CheckAwtEventQueueAccess {
public static void main(String[] args) {
// By using setProperty() method is to set the policy property 
// with security manager
System.setProperty("java.security.policy", "file:/C:/java.policy");
// Instantiating a SecurityManager object
SecurityManager smgr = new SecurityManager();
// By using setSecurityManager() method is to set the
// security manager
System.setSecurityManager(smgr);
// By using CheckAwtEventQueueAccess() method is to check 
// that awt event queue is accessed or not
smgr.checkAwtEventQueueAccess();
// Display the message when queue is acessible
System.out.println("Not Restricted..");
}
}

Output

输出量

Exception in thread "main" java.security.AccessControlException: access denied (
java.awt.AWTPermission accessEventQueue)
at java.security.AccessControlContext.checkPermission(AccessControlConte
xt.java:264)
at java.security.AccessController.checkPermission(AccessController.java:
427)
at java.lang.SecurityManager.checkPermission(SecurityManager.java:532)
at java.lang.SecurityManager.checkAwtEventQueueAccess(SecurityManager.ja
va:1398)
at CheckAwtEventQueueAccess.main(CheckAwtEventQueueAccess.java:18)

翻译自: https://www.includehelp.com/java/securitymanager-checkawteventqueueaccess-method-with-example.aspx