帮我看看啊,大哥大姐们!
fiore 2006-08-17 05:47:43 import java.awt.*; import java.awt.event.*;
import java.io.*;
class Example20_5
{ public static void main(String args[])
{ char a[]="今天晚上十点发起总攻".toCharArray();
int n,m;
try{ File f=new File("D:\\program","secret.txt");
for(int i=0;i<a.length;i++)
{ a[i]=(char)(a[i]^'R');
}
FileWriter out=new FileWriter(f);
out.write(a,0,a.length);
out.close();
FileReader in=new FileReader(f);
int length=(int)f.length();
char tom[]=new char[length];
while((n=in.read(tom,0,tom.length))!=-1)
{ String s=new String(tom,0,n);
System.out.println("密文: "+s);
}
in.close();
m=n;
for(int i=0;i<m;i++)
{ tom[i]=(char)(tom[i]^'R');
}
String s1=new String(tom,0,m);
System.out.println("明文: "+s1);
}
catch(IOException e)
{ System.out.println("Error");
}
}
}
Exception in thread "main" java.lang.String Index OutOfBoundsException:String index out of range: -1
at java.lang.String<init><String.java:192>
at Example20_5.main<Example20_5.java:27>
明文的内容不能显示出来,初学者,大家帮我看看啊!