字节流缓存

import java.io.*;
class MyBufferedInputStream{

private InputStream in;
private byte[] buf = byte[1024*4];
private int pos = 0,count = 0;//指针，计数器

MyBufferedInputStream(InputStream in)
{
this.in=in;
}
public int myRead()
{
if(count==0){
count = in.read(buf);//读取字符流，存入数组
if(count<0)            //结尾
return -1;
pos=0;
byte b= buf[pos];
count--;
pos++;
return b&0xff;
}else if (count>0){
byte b= buf[pos];
count--;
pos++;
return b&0xff;//避免文件中连续八个1，返回后为-1
}
return -1;
}
public void myClose()throws IOException
{
in.close();
}
}