理解错了,我以为你是要通过socket监听http请求。要是只做服务的话,没有问题,像tomcat就是用socket实现的,简单的,就是监听一个端口,当浏览器访问的时候,就向这个端口发送一个http协议,服务器解析后,返回给浏览器。这有个最简单的小例子,分server,request,response 3个类, server就是起socket监听, request解析接收的inputstream response响应。 推荐一本好书 how tomcat works 楼下代码:
import java.net.Socket; import java.net.ServerSocket; import java.net.InetAddress; import java.io.InputStream; import java.io.OutputStream; import java.io.IOException; import java.io.File;public class HttpServer { /** * WEB_ROOT is the directory where our HTML and other files reside. For * this package, WEB_ROOT is the "webroot" directory under the working * directory. The working directory is the location in the file system * from where the java command was invoked. */ public static final String WEB_ROOT = System.getProperty("user.dir")+File.separator+"webroot"; // shutdown command private static final String SHUTDOWN_COMMAND = "/SHUTDOWN"; // the shutdown command received private boolean shutdown = false; public static void main(String[] args) { HttpServer server = new HttpServer(); server.await(); } public void await() { ServerSocket serverSocket = null; int port = 8080; try { serverSocket = new ServerSocket(port, 1, InetAddress.getByName("127.0.0.1")); } catch (IOException e) { e.printStackTrace(); System.exit(1); } // Loop waiting for a request while (!shutdown) { Socket socket = null; InputStream input = null; OutputStream output = null; try { socket = serverSocket.accept(); input = socket.getInputStream(); output = socket.getOutputStream(); // create Request object and parse Request request = new Request(input); request.parse(); // create Response object Response response = new Response(output); response.setRequest(request); response.sendStaticResource(); // Close the socket socket.close(); // check if the previous URI is a shutdown // command shutdown = request.getUri().equals(SHUTDOWN_COMMAND); } catch (Exception e) { e.printStackTrace(); continue; } } } }import java.io.InputStream; import java.io.IOException;public class Request { private InputStream input; private String uri; public Request(InputStream input) { this.input = input; } public void parse() { // Read a set of characters from the socket StringBuffer request = new StringBuffer(2048); int i; byte[] buffer = new byte[2048]; try { i = input.read(buffer); } catch (IOException e) { e.printStackTrace(); i = -1; } for (int j=0; j<i; j++) { request.append((char) buffer[j]); } System.out.print(request.toString()); uri = parseUri(request.toString()); } private String parseUri(String requestString) { int index1, index2; index1 = requestString.indexOf(' '); if (index1 != -1) { index2 = requestString.indexOf(' ', index1 + 1); if (index2 > index1) return requestString.substring(index1 + 1, index2); } return null; } public String getUri() { return uri; }} import java.io.OutputStream; import java.io.IOException; import java.io.FileInputStream; import java.io.File;/* HTTP Response = Status-Line *(( general-header | response-header | entity-header ) CRLF) CRLF [ message-body ] Status-Line = HTTP-Version SP Status-Code SP Reason-Phrase CRLF */public class Response { private static final int BUFFER_SIZE = 1024; Request request; OutputStream output; public Response(OutputStream output) { this.output = output; } public void setRequest(Request request) { this.request = request; } public void sendStaticResource() throws IOException { byte[] bytes = new byte[BUFFER_SIZE]; FileInputStream fis = null; try { File file = new File(HttpServer.WEB_ROOT, request.getUri()); if (file.exists()) { fis = new FileInputStream(file); int ch = fis.read(bytes, 0, BUFFER_SIZE); while (ch!=-1) { output.write(bytes, 0, ch); ch = fis.read(bytes, 0, BUFFER_SIZE); } } else { // file not found String errorMessage = "HTTP/1.1 404 File Not Found\r\n" + "Content-Type: text/html\r\n" + "Content-Length: 23\r\n" + "\r\n" + "<h1>File Not Found</h1>"; output.write(errorMessage.getBytes()); } } catch (Exception e) { // thrown if cannot instantiate a File object System.out.println(e.toString() ); } finally { if (fis!=null) fis.close(); } } }
server就是起socket监听,
request解析接收的inputstream
response响应。
推荐一本好书 how tomcat works
楼下代码:
import java.net.ServerSocket;
import java.net.InetAddress;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.IOException;
import java.io.File;public class HttpServer
{
/**
* WEB_ROOT is the directory where our HTML and other files reside. For
* this package, WEB_ROOT is the "webroot" directory under the working
* directory. The working directory is the location in the file system
* from where the java command was invoked.
*/
public static final String WEB_ROOT = System.getProperty("user.dir")+File.separator+"webroot";
// shutdown command
private static final String SHUTDOWN_COMMAND = "/SHUTDOWN";
// the shutdown command received
private boolean shutdown = false; public static void main(String[] args)
{
HttpServer server = new HttpServer();
server.await();
} public void await()
{
ServerSocket serverSocket = null;
int port = 8080;
try
{
serverSocket = new ServerSocket(port, 1, InetAddress.getByName("127.0.0.1"));
}
catch (IOException e)
{
e.printStackTrace();
System.exit(1);
}
// Loop waiting for a request
while (!shutdown)
{
Socket socket = null;
InputStream input = null;
OutputStream output = null;
try
{
socket = serverSocket.accept();
input = socket.getInputStream();
output = socket.getOutputStream();
// create Request object and parse
Request request = new Request(input);
request.parse();
// create Response object
Response response = new Response(output);
response.setRequest(request);
response.sendStaticResource();
// Close the socket
socket.close();
// check if the previous URI is a shutdown
// command
shutdown = request.getUri().equals(SHUTDOWN_COMMAND);
}
catch (Exception e)
{
e.printStackTrace();
continue;
}
}
}
}import java.io.InputStream;
import java.io.IOException;public class Request { private InputStream input;
private String uri; public Request(InputStream input) {
this.input = input;
} public void parse() {
// Read a set of characters from the socket
StringBuffer request = new StringBuffer(2048);
int i;
byte[] buffer = new byte[2048];
try {
i = input.read(buffer);
}
catch (IOException e) {
e.printStackTrace();
i = -1;
}
for (int j=0; j<i; j++) {
request.append((char) buffer[j]);
}
System.out.print(request.toString());
uri = parseUri(request.toString());
} private String parseUri(String requestString) {
int index1, index2;
index1 = requestString.indexOf(' ');
if (index1 != -1) {
index2 = requestString.indexOf(' ', index1 + 1);
if (index2 > index1)
return requestString.substring(index1 + 1, index2);
}
return null;
} public String getUri() {
return uri;
}}
import java.io.OutputStream;
import java.io.IOException;
import java.io.FileInputStream;
import java.io.File;/*
HTTP Response = Status-Line
*(( general-header | response-header | entity-header ) CRLF)
CRLF
[ message-body ]
Status-Line = HTTP-Version SP Status-Code SP Reason-Phrase CRLF
*/public class Response { private static final int BUFFER_SIZE = 1024;
Request request;
OutputStream output; public Response(OutputStream output) {
this.output = output;
} public void setRequest(Request request) {
this.request = request;
} public void sendStaticResource() throws IOException {
byte[] bytes = new byte[BUFFER_SIZE];
FileInputStream fis = null;
try {
File file = new File(HttpServer.WEB_ROOT, request.getUri());
if (file.exists()) {
fis = new FileInputStream(file);
int ch = fis.read(bytes, 0, BUFFER_SIZE);
while (ch!=-1) {
output.write(bytes, 0, ch);
ch = fis.read(bytes, 0, BUFFER_SIZE);
}
}
else {
// file not found
String errorMessage = "HTTP/1.1 404 File Not Found\r\n" +
"Content-Type: text/html\r\n" +
"Content-Length: 23\r\n" +
"\r\n" +
"<h1>File Not Found</h1>";
output.write(errorMessage.getBytes());
}
}
catch (Exception e) {
// thrown if cannot instantiate a File object
System.out.println(e.toString() );
}
finally {
if (fis!=null)
fis.close();
}
}
}
工程下建一个webroot的文件夹,里面放几html页就可以直接访问
如:
http://127.0.0.1:8080/index.html
package org.sl.test;import java.net.InetSocketAddress;
import java.net.ServerSocket;
import java.net.Socket;
import java.net.SocketAddress;/**
* 忽悠人的http 服务器
* @author shanl
*
*/
public class HttpServer {
static public void start(){
StringBuilder echo = new StringBuilder();
echo.append("<html>");
echo.append("<head>");
echo.append("<title>hello</title>");
echo.append("</head>");
echo.append("<body>");
echo.append("<center>");
echo.append("<b1>Welcome to my home page.</b1>");
echo.append("</center>");
echo.append("</body>");
echo.append("</html>");
ServerSocket ss = null;
int port = 8010;
SocketAddress address = null;
Socket connect = null;
byte[] buffer = new byte[512];
int readLen = 0;
try{
System.out.println("开始监听:" + port);
address = new InetSocketAddress("192.168.2.23", port);
ss = new ServerSocket();
ss.bind(address);
while(true){
connect = ss.accept();
do{
readLen = connect.getInputStream().read(buffer);
System.out.println(new String(buffer));
}while(readLen == 512);
connect.getOutputStream().write(echo.toString().getBytes());
connect.close();
}
}catch(Exception ex){
ex.printStackTrace();
}
}
public static void main(String[] args){
start();
}
}