Java SecurityManager的checkSecurityAccess（）方法与示例

SecurityManager类的checkSecurityAccess()方法 (SecurityManager Class checkSecurityAccess() method)

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

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

• checkSecurityAccess() method is used to check whether the permission with the given permission t_name(target name) should be allowed (i.e. granted) or not allowed (i.e. denied) and it calls checkPermission with the SecurityPermission object for the given t_name(target name).

  checkSecurityAccess()方法用于检查是否应允许(即授予)具有给定许可权t_name(目标名称)的许可权(即被拒绝)，并使用给定t_name(目标名称)的SecurityPermission对象调用checkPermission 。

• checkSecurityAccess() 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.

  checkSecurityAccess()方法是一个非静态方法，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。

• checkSecurityAccess() method may throw an exception at the time of checking granted permission.

  在检查授予的权限时， checkSecurityAccess()方法可能会引发异常。

  • SecurityException – This exception may throw when the calling thread is denied for the requested access.
  • NullPointerException – This exception may throw when the given parameter t_name is null.
  • IllegalArgumentException – This exception may throw when the given parameter t_name is blank or empty.

Syntax:

句法：

    public void checkSecurityAccess(String t_name);

Parameter(s):

参数：

• String t_name – represents the target name of the SecurityPermission.

  字符串t_name –表示SecurityPermission的目标名称。

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 checkSecurityAccess(String t_name)
// method of SecurityManager 

public class CheckSecurityAccess extends SecurityManager {
     
    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 CheckSecurityAccess object
        CheckSecurityAccess csa = new CheckSecurityAccess();

        // By using setSecurityManager() method is to set the
        // security manager
        System.setSecurityManager(csa);

        // By using checkSecurityAccess(string t_name) method is to
        //check restriction on which access
        csa.checkSecurityAccess("write");

        // Display the message
        System.out.println("Not Restricted..");
    }
}

Output

输出量

Exception in thread "main" java.security.AccessControlException: access denied ("java.security.SecurityPermission" "write")
	at java.base/java.security.AccessControlContext.checkPermission(AccessControlContext.java:472)
	at java.base/java.security.AccessController.checkPermission(AccessController.java:897)
	at java.base/java.lang.SecurityManager.checkPermission(SecurityManager.java:322)
	at java.base/java.lang.SecurityManager.checkSecurityAccess(SecurityManager.java:1435)
	at CheckSecurityAccess.main(CheckSecurityAccess.java:20)

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