sockdata.java

java写的用于远程执行程序的shell程序

import java.net.*;
import java.io.*;
import java.util.*;


class SockData
{
	static final byte[] Read(BufferedInputStream inStream) throws Exception
	{
		// read the length of the data into 4 byte
		// this is to make it platform independent
		byte[] pSize = new byte[4];
		int nTotal = 0;
		int nRead = 0;
		while(nTotal<4)
		{	
			nRead = inStream.read(pSize,nTotal,4-nTotal);
			if(nRead<0) break;
			nTotal += nRead;
		}
		int nSize = (pSize[0]&0x000000ff)|((pSize[1]&0x000000ff)<<8)|((pSize[2]&0x000000ff)<<16)|((pSize[3]&0x000000ff)<<24);
		if(nRead<0||nSize<0) throw new Exception("Invalid input data");
		// then read the actual data into a byte array
		if(nSize==0) return "".getBytes();
		byte[] pData = new byte[nSize];
		nTotal = 0;
		nRead = 0;
		while(nTotal<nSize)
		{	
			nRead = inStream.read(pData,nTotal,nSize-nTotal);
			if(nRead<0) break;
			nTotal += nRead;
		}
		if(nRead<0) throw new Exception("Invalid input data");
		return pData;
	}
	static final void Write(BufferedOutputStream outStream, byte[] pData, int nSize) throws Exception
	{
		if(nSize>=0)
		{
			// write the length of the data as a 4-byte array
			// this is to make it platform-independent
			byte[] pSize=
			{
				(byte)(0x000000ff&nSize),
				(byte)(0x000000ff&(nSize>>8)),
				(byte)(0x000000ff&(nSize>>16)),
				(byte)(0x000000ff&(nSize>>24))
			};
			// then write the actual data in the given byte array
			outStream.write(pSize,0,4);
			if(nSize>0)
			{
				if(pData!=null&&pData.length>=nSize) outStream.write(pData,0,nSize);
				else throw new Exception("Invalid output data");
			}
			outStream.flush();
		}
	}
}