package IO;

import java.io.File;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.RandomAccessFile;

public class TestRandomAccessFile {
public static void main(String args[]) throws IOException {
RandomAccessFile r =
new RandomAccessFile
//常见模式有r(读),rw(写)
(new File("D:/java_foundation/src/IO/TestFile1.java"), "r");
r.seek(2);
byte[] b = new byte[1024];
int len;
while((len = r.read(b))!=-1) {
System.out.println(new String(b,0,b.length));
}
r.close();
}
}
有大佬知道 System.out.println(new String(b,0,b.length));与 System.out.println(new String(b,0,b.len));区别在哪，为什么如果用b. length有的不能输出吗