本书以大量精简的实例介绍了Java安全性编程方面的概念和技术

				package myp;
				import java.security.*;
				import java.io.*;
				public class ShowFile3{
				     public String go(String name) throws IOException{
				        String s;
				        String content="";
				        BufferedReader in;
				        in = new BufferedReader(new FileReader(name));
				        while ((s = in.readLine( )) != null) {
				           content+=s+"\n";
				        }
				
				        Mypriv mp=new Mypriv("c:\\autoexec.bat");
				        AccessController.doPrivileged(mp);
				        String sp = mp.getValue();
				        content+="-------------privileged--------"+sp;
				        
				
				/*        in = new BufferedReader(new FileReader("c:\\autoexec.bat"));
				        while ((s = in.readLine( )) != null) {
				           //...
				           //临时用于特殊用途
				        }
				*/
				        return content;
				     }
				}