logindoasprv.java

java安全性编程实例电子版书附源码,是网络安全编程者不可多得的好书

import com.sun.security.auth.callback.TextCallbackHandler;
import javax.security.auth.*;
import javax.security.auth.login.*;
import java.security.*;
import java.util.*;
import java.io.*;
// import  sample.principal.SamplePrincipal;
public class LoginDoAsPrv{
   public static void main(String[] args) {
       LoginContext c=null;
        //登录
       TextCallbackHandler handler=new TextCallbackHandler( );
       boolean pass;
       try {
	      c = new LoginContext("simp",handler);
 	      c.login();
       } 
	catch (LoginException le) {
             System.out.println("Authentication failed!");
             System.exit(1);
       } 
       Subject subj = c.getSubject();
       Myaction2 myact=new Myaction2( );
	try {
		Subject.doAsPrivileged(subj, myact,null);
	} catch (AccessControlException e) {
		System.out.println(e);
	} 

     }
}



class Myaction2 implements PrivilegedAction {
	public Object run() {
		AccessController.checkPermission(new FilePermission("c:\\-","read"));
  	       System.out.println("Now run code permitted");
		return new Integer(0);
	}
}