PHP实现java中的DatainputStream类.

在项目中,碰到一个解析流的操作,php里面没有现成的类. 
那没办法,只能用二进制模式打开文件,再和java的datainputstream对比着打开文件,一个一个的实现流读取和解析. 

废话不多说,代码贴出,其实很简单很简单. 

DataInputStream.php

<?php
/**
 * 流解析
 * ---------------------------------------------
 * @Author: Simon 夏向红 sanwkj@163.com
 * @Date: 2012-02-22
 * @package cn.com.nearme.gostore.theme
 * @name :DataInputStream.php
 * @version v1.0
 * 
*/
class DataInputStream {
    private $stream = null;
     
    /**
     * 构造函数
     *
     * @param stream of fopen .. $in
     */
    public function __construct( $in ){
        $this->stream = $in;
    }
     
    /**
     * 析构函数
     *
     */
    public function __destruct(){
        @fclose( $this->stream );
    }
     
    /**
     * 读取字节
     *
     * @param int sizeof you want to read $len
     * @return string
     */
    private function read( $len=1 ){
        $len = intval( $len );
        if( $len>0 ) {
            if( !feof( $this->stream ) ) {
                $read = @fread($this->stream,$len);
                if( strlen($read)!=$len ){
                    throw new Exception(&#39;流文件已经到末尾，读取错误&#39;,222);
                } else {
                    return $read;
                }
            } else {
                throw new Exception(&#39;流文件已经到末尾，读取错误&#39;,222);
            }
        } else {
            return &#39;&#39;;
        }
    }
     
    /**
     * 读取一个字节,并转换成int
     *
     * @return int
     */
    public function readByte(){
        return hexdec(bin2hex($this->read(1)));
    }
     
    /**
     * 短整形
     *
     * @return int
     */
    public function readShort(){
        return hexdec(bin2hex($this->read(2)));
    }
     
    /**
     * 整形数据
     *
     * @return int
     */
    public function readInt(){
        return hexdec(bin2hex($this->read(4)));
    }
     
    /**
     * 读取一个字符串
     *
     * @return string
     */
    public function readUTF(){
        $len = $this->readShort();
        return $this->read($len);
    }
     
    /**
     * 读取指定长度的数据,并作为字符串返回,图片等二进制文件,可能需要这样读取.
     *
     * @param int $len
     * @return unknown
     */
    public function readFully( $len ) {
        return $this->read( $len );
    }
     
    /**
     * readUTF的别名
     *
     * @return unknown
     */
    public function readString(){
        return $this->readUTF();
    }
     
    /**
     * 长整形.
     *
     * @return unknown
     */
    public function readLong(){
        return hexdec(bin2hex($this->read(8)));
    }
}
?>