自己实现httpsever、httpproxy、ServletServer

package gaofeng.myhttp.v1;

import java.io.BufferedReader;
import java.io.File;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.net.Inet4Address;
import java.net.ServerSocket;
import java.net.Socket;
import java.net.URLDecoder;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.Paths;
import java.util.concurrent.Executor;
import java.util.concurrent.Executors;

public class WebServer {
	private static Executor pool = Executors.newFixedThreadPool(5);
	public static void main(String[] args) {
		try (ServerSocket server = new ServerSocket(5566, 5, Inet4Address.getLoopbackAddress());){
			while(true) {
				Socket socket= server.accept();
				pool.execute(()->dealRequest(socket));
			}
			
		} catch (IOException e) {
			e.printStackTrace();
		}		

	}
	private static void dealRequest(Socket socket) {
		System.out.println("---- RemoteSocketAddress : " + socket.getRemoteSocketAddress());
		try {
			BufferedReader reader = new BufferedReader(new InputStreamReader(socket.getInputStream()));
			
			String firstline = null;
			while(true) {
				String line = reader.readLine();
				if(line==null || line.equals("") ) {
					System.out.println("---- end:"+line);
					break;
				}
				
				if(firstline==null) {
					firstline=line;
				}
				System.out.println(">"+line);
			}
			String s[] = firstline.split(" ");
			OutputStream output = socket.getOutputStream();
			try {
				if(s[0].equalsIgnoreCase("get")) {
					String filename = URLDecoder.decode(s[1],"utf-8");
					
					int index = s[1].indexOf(":5566/");
					if(index>-1) {
						String path = s[1].substring(index + ":5566/".length());
						filename = path;
					}
					
					String baseDir = System.getProperty("user.dir") + "/webroot/";
					Path filePath = Paths.get(baseDir, filename);
					if(filePath.toFile().isDirectory()){
						StringBuilder sb = new StringBuilder();
						for (File file : filePath.toFile().listFiles()) {
							if(file.isFile()) {
								sb.append("<a href=\"" + file.getName()+"\">"+file.getName()+"</a><br>");
							}else {
								sb.append("<a href=\"" + file.getName()+"/\">"+file.getName()+"</a><br>");
							}
						} 
						byte[] content = sb.toString().getBytes("GBK");
						output.write(String.format("http/1.1 200 ok\r\nContent-Type: text/html\r\nContent-Length: %d\r\n\r\n", content.length).getBytes());
						output.write(content);
					}else {
						byte[] fileContent = Files.readAllBytes(filePath);
						output.write(String.format("http/1.1 200 ok\r\nContent-Type: text/html\r\nContent-Length: %d\r\n\r\n", fileContent.length).getBytes());
						output.write(fileContent);						
					}
	
					return;
				}
			}catch(Exception e) {e.printStackTrace();}
			
			String notfound = "<h1>File not found!</h1>";
			byte[] response = String.format("http/1.1 404 File not found\r\nContent-Type: text/html\r\nContent-Length: %d\r\n\r\n%s",notfound.length(), notfound).getBytes();
			output.write(response);
		}catch(Throwable e) {
			e.printStackTrace();
		}finally {
			try {
				socket.close();
			} catch (IOException e) {
				e.printStackTrace();
			}
		}
	}

}

参考 https://blog.csdn.net/dotalee/article/details/77838659

curl -sv --proxy 127.0.0.1:80 http://www.baidu.com

curl -sv --proxy 127.0.0.1:80 https://www.baidu.com

curl --proxy 127.0.0.1:80 http://127.0.0.1:5566/mm/

package gaofeng.myhttp.v1;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.net.ServerSocket;
import java.net.Socket;

public class HttpProxy {

	public static void main(String[] args) throws IOException {
		ServerSocket serverSocket = new ServerSocket(80);
		for (;;) {
			new SocketHandle(serverSocket.accept()).start();
		}
	}
}
class SocketHandle extends Thread{
	private Socket socket;
	public SocketHandle(Socket socket) {
		this.socket = socket;
	}
	@Override
    public void run() {
		try {
			_run();
		} catch (IOException e) {
			e.printStackTrace();
		}
	}

    public void _run() throws IOException {
		BufferedReader reader = new BufferedReader(new InputStreamReader(socket.getInputStream()));
		StringBuilder headStr = new StringBuilder();
		
		String host="",port="";//http协议头  Host: 127.0.0.1
		while(true) {
			String line = reader.readLine();
			if(line==null) {
				System.out.println("---- end:"+line);
				break;
			}else {
				System.out.println(line);
				headStr.append(line).append("\r\n");
			}
			if (line.length() == 0) {
                break;
			}
			
            if (line.startsWith("Host:")) {
                host = line.substring(line.indexOf(' ')+1);
                if(host.contains(":")) {
                	port=host.split(":")[1];
                	host=host.split(":")[0];
                }else {
                	port="80";
                }
            }
		}
		
        String httpMethod="";
        if(headStr.length()>0) {
        	httpMethod = headStr.substring(0, headStr.indexOf(" "));//http协议第一行   GET /mm/ HTTP/1.1
        }
        try(Socket proxySocket = new Socket(host, Integer.parseInt(port))){
        	InputStream proxyInput = proxySocket.getInputStream();
        	OutputStream proxyOutput = proxySocket.getOutputStream();
            //根据HTTP method来判断是https还是http请求
            if ("CONNECT".equalsIgnoreCase(httpMethod)) {//https先建立隧道
                socket.getOutputStream().write("HTTP/1.1 200 Connection Established\r\n\r\n".getBytes());
                socket.getOutputStream().flush();
            } else {//http直接将请求头转发
                proxyOutput.write(headStr.toString().getBytes());
            }
            //新开线程转发客户端请求至目标服务器
            new ProxyHandleThread(socket.getInputStream(), proxyOutput).start();
            //转发目标服务器响应至客户端
            while (true) {
            	int b = proxyInput.read();
            	
            	if(b==-1) {
            		socket.getOutputStream().close();
            		break;
            	}else {
            		socket.getOutputStream().write(b);
            	}
            	
            }
        }		
	}
}
class ProxyHandleThread extends Thread{
	private InputStream input;
    private OutputStream output;

    public ProxyHandleThread(InputStream input, OutputStream output) {
        this.input = input;
        this.output = output;
    }

    @Override
    public void run() {
        try {
            while (true) {
            	int b = input.read();
            	if(b==-1) {
            		break;
            	}else {
            		System.out.println("ddd"+b);
            		output.write(b);
            	}
            }
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

ServletServer （注意，socket流只能读一次。所以一般由框架读取http头，应用读取body。）

package gaofeng.myhttp.v2;

import java.io.BufferedReader;
import java.io.File;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.PrintWriter;
import java.io.UnsupportedEncodingException;
import java.net.Inet4Address;
import java.net.ServerSocket;
import java.net.Socket;
import java.net.URL;
import java.net.URLClassLoader;
import java.net.URLDecoder;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.Paths;
import java.security.Principal;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Enumeration;
import java.util.List;
import java.util.Locale;
import java.util.Map;
import java.util.concurrent.Executor;
import java.util.concurrent.Executors;

import javax.servlet.AsyncContext;
import javax.servlet.DispatcherType;
import javax.servlet.RequestDispatcher;
import javax.servlet.ServletContext;
import javax.servlet.ServletException;
import javax.servlet.ServletInputStream;
import javax.servlet.ServletOutputStream;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.http.Cookie;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import javax.servlet.http.HttpUpgradeHandler;
import javax.servlet.http.Part;

public class ServletServer {
	private static Executor pool = Executors.newFixedThreadPool(5);
	public static void main(String[] args) {
		try (ServerSocket server = new ServerSocket(5566, 5, Inet4Address.getLoopbackAddress());){
			while(true) {
				Socket socket= server.accept();
				pool.execute(()->dealRequest(socket));
			}
			
		} catch (IOException e) {
			e.printStackTrace();
		}		

	}

	private static void dealRequest(Socket socket) {
		System.out.println("---- RemoteSocketAddress : " + socket.getRemoteSocketAddress());
		try {
			String firstLine = Util.readLine(socket.getInputStream());
			String[] s = firstLine.split(" ");
			String method = s[0],url = s[1],protocal = s[2];
			
			List<String> headerList= new ArrayList<>();
			while(true) {
				String line = Util.readLine(socket.getInputStream());
				System.out.println("===" + line);
				headerList.add(line);
				if(line.length()==0) break;
			}
			
			if(url.startsWith("/servlet/")) {
				new ServletProcessor().handle(firstLine,socket);
			}else if(url.startsWith("/static/")) {
				new StaticProcessor().handle(firstLine,socket);
			}else {
				String notfound = "<h1>File not found!</h1>";
				byte[] response = String.format("http/1.1 404 File not found\r\nContent-Type: text/html\r\nContent-Length: %d\r\n\r\n%s",notfound.length(), notfound).getBytes();

				socket.getOutputStream().write(response);
				
			}
		} catch (Throwable e) {
			e.printStackTrace();
		} finally {
			try {
				socket.close();
			} catch (IOException e) {
				e.printStackTrace();
			}
		}
	}
}
class ServletProcessor{
	public void handle(String firstLine, Socket socket) throws ClassNotFoundException, InstantiationException, IllegalAccessException, ServletException, IOException {
		URL[] urls = { ServletServer.class.getResource("/")};//{ new URL("file://Users/apple/temp")};
		System.out.println(ServletServer.class.getResource("/"));
		Class<?> clazz = new URLClassLoader(urls).loadClass("gaofeng.myhttp.v2.MyServlet");
		HttpServlet httpServlet = (HttpServlet) clazz.newInstance();
		
		Request request = new Request();
		request.init(firstLine, socket);
		Response response = new Response();
		response.init( socket);
		httpServlet.service(request, response);
	}
}
class Request implements HttpServletRequest{
	private Socket socket;
	
	private String method,url,protocal;
    public void init(String firstLine, Socket socket) {
    	this.socket = socket;
    	String[] s = firstLine.split(" ");
		method = s[0];
		url = s[1];
		protocal = s[2];
    	
    }
	@Override
	public Object getAttribute(String name) {
		// TODO Auto-generated method stub
		return null;
	}

	@Override
	public Enumeration<String> getAttributeNames() {
		// TODO Auto-generated method stub
		return null;
	}

	@Override
	public String getCharacterEncoding() {
		// TODO Auto-generated method stub
		return null;
	}

	@Override
	public void setCharacterEncoding(String env) throws UnsupportedEncodingException {
		// TODO Auto-generated method stub
		
	}

	@Override
	public int getContentLength() {
		// TODO Auto-generated method stub
		return 0;
	}

	@Override
	public long getContentLengthLong() {
		// TODO Auto-generated method stub
		return 0;
	}

	@Override
	public String getContentType() {
		// TODO Auto-generated method stub
		return null;
	}

	@Override
	public ServletInputStream getInputStream() throws IOException {
		return null;
	}

	@Override
	public String getParameter(String name) {
		// TODO Auto-generated method stub
		return null;
	}

	@Override
	public Enumeration<String> getParameterNames() {
		// TODO Auto-generated method stub
		return null;
	}

	@Override
	public String[] getParameterValues(String name) {
		// TODO Auto-generated method stub
		return null;
	}

	@Override
	public Map<String, String[]> getParameterMap() {
		// TODO Auto-generated method stub
		return null;
	}

	@Override
	public String getProtocol() {
		return this.protocal;
	}

	@Override
	public String getScheme() {
		// TODO Auto-generated method stub
		return null;
	}

	@Override
	public String getServerName() {
		// TODO Auto-generated method stub
		return null;
	}

	@Override
	public int getServerPort() {
		// TODO Auto-generated method stub
		return 0;
	}

	@Override
	public BufferedReader getReader() throws IOException {
		// TODO Auto-generated method stub
		return null;
	}

	@Override
	public String getRemoteAddr() {
		return socket.getRemoteSocketAddress().toString();
	}

	@Override
	public String getRemoteHost() {
		// TODO Auto-generated method stub
		return null;
	}

	@Override
	public void setAttribute(String name, Object o) {
		// TODO Auto-generated method stub
		
	}

	@Override
	public void removeAttribute(String name) {
		// TODO Auto-generated method stub
		
	}

	@Override
	public Locale getLocale() {
		// TODO Auto-generated method stub
		return null;
	}

	@Override
	public Enumeration<Locale> getLocales() {
		// TODO Auto-generated method stub
		return null;
	}

	@Override
	public boolean isSecure() {
		// TODO Auto-generated method stub
		return false;
	}

	@Override
	public RequestDispatcher getRequestDispatcher(String path) {
		// TODO Auto-generated method stub
		return null;
	}

	@Override
	public String getRealPath(String path) {
		// TODO Auto-generated method stub
		return null;
	}

	@Override
	public int getRemotePort() {
		// TODO Auto-generated method stub
		return 0;
	}

	@Override
	public String getLocalName() {
		// TODO Auto-generated method stub
		return null;
	}

	@Override
	public String getLocalAddr() {
		// TODO Auto-generated method stub
		return null;
	}

	@Override
	public int getLocalPort() {
		// TODO Auto-generated method stub
		return 0;
	}

	@Override
	public ServletContext getServletContext() {
		// TODO Auto-generated method stub
		return null;
	}

	@Override
	public AsyncContext startAsync() throws IllegalStateException {
		// TODO Auto-generated method stub
		return null;
	}

	@Override
	public AsyncContext startAsync(ServletRequest servletRequest, ServletResponse servletResponse)
			throws IllegalStateException {
		// TODO Auto-generated method stub
		return null;
	}

	@Override
	public boolean isAsyncStarted() {
		// TODO Auto-generated method stub
		return false;
	}

	@Override
	public boolean isAsyncSupported() {
		// TODO Auto-generated method stub
		return false;
	}

	@Override
	public AsyncContext getAsyncContext() {
		// TODO Auto-generated method stub
		return null;
	}

	@Override
	public DispatcherType getDispatcherType() {
		// TODO Auto-generated method stub
		return null;
	}

	@Override
	public String getAuthType() {
		// TODO Auto-generated method stub
		return null;
	}

	@Override
	public Cookie[] getCookies() {
		// TODO Auto-generated method stub
		return null;
	}

	@Override
	public long getDateHeader(String name) {
		// TODO Auto-generated method stub
		return 0;
	}

	@Override
	public String getHeader(String name) {
		// TODO Auto-generated method stub
		return null;
	}

	@Override
	public Enumeration<String> getHeaders(String name) {
		// TODO Auto-generated method stub
		return null;
	}

	@Override
	public Enumeration<String> getHeaderNames() {
		// TODO Auto-generated method stub
		return null;
	}

	@Override
	public int getIntHeader(String name) {
		// TODO Auto-generated method stub
		return 0;
	}

	@Override
	public String getMethod() {
		return this.method;
	}

	@Override
	public String getPathInfo() {
		return this.url;
	}

	@Override
	public String getPathTranslated() {
		// TODO Auto-generated method stub
		return null;
	}

	@Override
	public String getContextPath() {
		// TODO Auto-generated method stub
		return null;
	}

	@Override
	public String getQueryString() {
		// TODO Auto-generated method stub
		return null;
	}

	@Override
	public String getRemoteUser() {
		// TODO Auto-generated method stub
		return null;
	}

	@Override
	public boolean isUserInRole(String role) {
		// TODO Auto-generated method stub
		return false;
	}

	@Override
	public Principal getUserPrincipal() {
		// TODO Auto-generated method stub
		return null;
	}

	@Override
	public String getRequestedSessionId() {
		// TODO Auto-generated method stub
		return null;
	}

	@Override
	public String getRequestURI() {
		// TODO Auto-generated method stub
		return null;
	}

	@Override
	public StringBuffer getRequestURL() {
		// TODO Auto-generated method stub
		return null;
	}

	@Override
	public String getServletPath() {
		// TODO Auto-generated method stub
		return null;
	}

	@Override
	public HttpSession getSession(boolean create) {
		// TODO Auto-generated method stub
		return null;
	}

	@Override
	public HttpSession getSession() {
		// TODO Auto-generated method stub
		return null;
	}

	@Override
	public String changeSessionId() {
		// TODO Auto-generated method stub
		return null;
	}

	@Override
	public boolean isRequestedSessionIdValid() {
		// TODO Auto-generated method stub
		return false;
	}

	@Override
	public boolean isRequestedSessionIdFromCookie() {
		// TODO Auto-generated method stub
		return false;
	}

	@Override
	public boolean isRequestedSessionIdFromURL() {
		// TODO Auto-generated method stub
		return false;
	}

	@Override
	public boolean isRequestedSessionIdFromUrl() {
		// TODO Auto-generated method stub
		return false;
	}

	@Override
	public boolean authenticate(HttpServletResponse response) throws IOException, ServletException {
		// TODO Auto-generated method stub
		return false;
	}

	@Override
	public void login(String username, String password) throws ServletException {
		// TODO Auto-generated method stub
		
	}

	@Override
	public void logout() throws ServletException {
		// TODO Auto-generated method stub
		
	}

	@Override
	public Collection<Part> getParts() throws IOException, ServletException {
		// TODO Auto-generated method stub
		return null;
	}

	@Override
	public Part getPart(String name) throws IOException, ServletException {
		// TODO Auto-generated method stub
		return null;
	}

	@Override
	public <T extends HttpUpgradeHandler> T upgrade(Class<T> httpUpgradeHandlerClass)
			throws IOException, ServletException {
		// TODO Auto-generated method stub
		return null;
	}
	
}
class Response implements HttpServletResponse{
	private Socket socket;
    public void init(Socket socket) {
    	this.socket = socket;
    }
	@Override
	public String getCharacterEncoding() {
		// TODO Auto-generated method stub
		return null;
	}

	@Override
	public String getContentType() {
		// TODO Auto-generated method stub
		return null;
	}

	@Override
	public ServletOutputStream getOutputStream() throws IOException {
		// TODO Auto-generated method stub
		return null;
	}

	@Override
	public PrintWriter getWriter() throws IOException {
		// TODO Auto-generated method stub
		return null;
	}

	@Override
	public void setCharacterEncoding(String charset) {
		// TODO Auto-generated method stub
		
	}

	@Override
	public void setContentLength(int len) {
		// TODO Auto-generated method stub
		
	}

	@Override
	public void setContentLengthLong(long length) {
		// TODO Auto-generated method stub
		
	}

	@Override
	public void setContentType(String type) {
		// TODO Auto-generated method stub
		
	}

	@Override
	public void setBufferSize(int size) {
		// TODO Auto-generated method stub
		
	}

	@Override
	public int getBufferSize() {
		// TODO Auto-generated method stub
		return 0;
	}

	@Override
	public void flushBuffer() throws IOException {
		// TODO Auto-generated method stub
		
	}

	@Override
	public void resetBuffer() {
		// TODO Auto-generated method stub
		
	}

	@Override
	public boolean isCommitted() {
		// TODO Auto-generated method stub
		return false;
	}

	@Override
	public void reset() {
		// TODO Auto-generated method stub
		
	}

	@Override
	public void setLocale(Locale loc) {
		// TODO Auto-generated method stub
		
	}

	@Override
	public Locale getLocale() {
		// TODO Auto-generated method stub
		return null;
	}

	@Override
	public void addCookie(Cookie cookie) {
		// TODO Auto-generated method stub
		
	}

	@Override
	public boolean containsHeader(String name) {
		// TODO Auto-generated method stub
		return false;
	}

	@Override
	public String encodeURL(String url) {
		// TODO Auto-generated method stub
		return null;
	}

	@Override
	public String encodeRedirectURL(String url) {
		// TODO Auto-generated method stub
		return null;
	}

	@Override
	public String encodeUrl(String url) {
		// TODO Auto-generated method stub
		return null;
	}

	@Override
	public String encodeRedirectUrl(String url) {
		// TODO Auto-generated method stub
		return null;
	}

	@Override
	public void sendError(int sc, String msg) throws IOException {
		this.socket.getOutputStream().write(String.format("http/1.1 %d %s\r\n", sc,msg).getBytes());
	}

	@Override
	public void sendError(int sc) throws IOException {
		// TODO Auto-generated method stub
		
	}

	@Override
	public void sendRedirect(String location) throws IOException {
		// TODO Auto-generated method stub
		
	}

	@Override
	public void setDateHeader(String name, long date) {
		// TODO Auto-generated method stub
		
	}

	@Override
	public void addDateHeader(String name, long date) {
		// TODO Auto-generated method stub
		
	}

	@Override
	public void setHeader(String name, String value) {
		// TODO Auto-generated method stub
		
	}

	@Override
	public void addHeader(String name, String value) {
		// TODO Auto-generated method stub
		
	}

	@Override
	public void setIntHeader(String name, int value) {
		// TODO Auto-generated method stub
		
	}

	@Override
	public void addIntHeader(String name, int value) {
		// TODO Auto-generated method stub
		
	}

	@Override
	public void setStatus(int sc) {
		// TODO Auto-generated method stub
		
	}

	@Override
	public void setStatus(int sc, String sm) {
		// TODO Auto-generated method stub
		
	}

	@Override
	public int getStatus() {
		// TODO Auto-generated method stub
		return 0;
	}

	@Override
	public String getHeader(String name) {
		// TODO Auto-generated method stub
		return null;
	}

	@Override
	public Collection<String> getHeaders(String name) {
		// TODO Auto-generated method stub
		return null;
	}

	@Override
	public Collection<String> getHeaderNames() {
		// TODO Auto-generated method stub
		return null;
	}
	
}
class StaticProcessor{
	public void handle( String firstLine, Socket socket){
		try {
			_handle(firstLine, socket);
			
		} catch (Exception e) {

			
			String notfound = "<h1>File not found!</h1>";
			notfound = "File not found!";
			byte[] response = String.format("http/1.1 404 File not found\r\nContent-Type: text/html\r\nContent-Length: %d\r\n\r\n%s",notfound.length(), notfound).getBytes();

			try {
				socket.getOutputStream().write(response);
			} catch (IOException e1) {
				e1.printStackTrace();
			}
		}
		
	}

	
	public void _handle(String firstLine, Socket socket) throws IOException {
		String s[] = firstLine.split(" ");
		String filename = URLDecoder.decode(s[1].substring(s[1].indexOf('/',1)),"utf-8");
		
		int index = s[1].indexOf(":5566/");
		if(index>-1) {
			String path = s[1].substring(index + ":5566/".length());
			filename = path;
		}
		
		String baseDir = System.getProperty("user.dir") + "/webroot/";
		Path filePath = Paths.get(baseDir, filename);
		OutputStream output = socket.getOutputStream();
		
		if(filePath.toFile().isDirectory()){
			StringBuilder sb = new StringBuilder();
			for (File file : filePath.toFile().listFiles()) {
				if(file.isFile()) {
					sb.append("<a href=\"" + file.getName()+"\">"+file.getName()+"</a><br>");
				}else {
					sb.append("<a href=\"" + file.getName()+"/\">"+file.getName()+"</a><br>");
				}
			} 
			byte[] content = sb.toString().getBytes("GBK");
			
			output.write(String.format("http/1.1 200 ok\r\nContent-Type: text/html\r\nContent-Length: %d\r\n\r\n", content.length).getBytes());
			output.write(content);
		}else if(filePath.toFile().isFile()){
			byte[] fileContent = Files.readAllBytes(filePath);
			
			output.write(String.format("http/1.1 200 ok\r\nContent-Type: text/html\r\nContent-Length: %d\r\n\r\n", fileContent.length).getBytes());
			output.write(fileContent);						
		}else {
			throw new IOException();
		}
	}
}
class MyServlet extends HttpServlet{
	@Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp)
            throws ServletException, IOException
        {
            String protocol = req.getProtocol();
            String msg = "http.method_get_not_supported";
            if (protocol.endsWith("1.1")) {
                resp.sendError(HttpServletResponse.SC_METHOD_NOT_ALLOWED, msg);
            } else {
                resp.sendError(HttpServletResponse.SC_BAD_REQUEST, msg);
            }
        }
}
class Util{
	public static String readLine(InputStream input) {
		try {
			byte[] buff = new byte[512];
			int length = 0;
			
			while(true) {
				int c = input.read();
				if(c==-1) {
					return new String(buff,0,length);
				}else if(c=='\n') {// "\r\n"
					return new String(buff,0,length-1);
				}else {
					buff[length++]=(byte)c;
				}				
			}
		} catch (IOException e) {
			e.printStackTrace();
		}
		
		return null;
	}
}