更多 Java IO & NIO方面的文章，请参见文集《Java IO & NIO》
- Instances of this class support both reading and writing to a random access file.
支持对文件的随机访问及读写操作。 - A random access file behaves like a large array of bytes stored in the file system. There is a kind of cursor, or index into the implied array, called the file pointer;
有一个游标或者索引 file pointer，来访问字节数组 -
getFilePointer()得到当前 file pointer -
seek(long pos)修改当前 file pointer
RandomAccessFile 的使用：
public static void main(String[] args) throws Exception {
RandomAccessFile raf = new RandomAccessFile("r.txt", "rw");
raf.writeUTF("你好");
System.out.println(raf.getFilePointer());
raf.seek(0);
String s = raf.readUTF();
System.out.println(s);
}
输出：
8
你好
