<满血复活之Tomcat原理实现> 创建一个基本的Server
今天看了How Tomcat work的第一章。
关键有三个类.
..HttpServer
..Request
..Response
HttpServer 主要是有个方法能处理http发起请求的url
import java.io.File;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.InetAddress;
import java.net.ServerSocket;
import java.net.Socket;
import java.net.UnknownHostException;
public class HttpServer {
public static final String WEB_ROOT=System.getProperty("user.dir")+File.separator+"webroot";
private static final String SHUTDOWN_COMMAND="/shutdown";
boolean shutdown = false;
public void await() throws IOException{
ServerSocket serverSocket = null;
int port = 8080;
try {
serverSocket = new ServerSocket(port,1,InetAddress.getByName("127.0.0.1"));
} catch (UnknownHostException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
System.exit(1);
}
while(!shutdown){
Socket socket = null;
InputStream input = null;
OutputStream output = null;
socket = serverSocket.accept();
input = socket.getInputStream();
output = socket.getOutputStream();
Request request = new Request(input);
request.parse();
Response response = new Response(output);
response.setRequest(request);
response.sendStaticResourse();
socket.close();
shutdown = request.getUri().equals(SHUTDOWN_COMMAND);
}
}
public static void main(String[] args) throws IOException {
HttpServer hs = new HttpServer();
hs.await();
System.out.println(WEB_ROOT);
}
}
Request类 处理socket流里面信息
import java.io.IOException;
import java.io.InputStream;
public class Request {
InputStream input = null;
String uri = null;
public Request(InputStream input) {
this.input = input;
}
public void parse(){
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(buffer[j]);
}
System.out.println(request.toString());
uri = parseUri(request.toString());
}
public String parseUri(String url){
int index1,index2;
index1 = url.indexOf(" ");
if(index1 != -1){
index2 = url.indexOf(" ", index1 + 1);
if(index2 > index1){
return url.substring(index1+1,index2);
}
}
return "";
}
public String getUri(){
return uri;
}
}
Response
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.OutputStream;
public class Response {
OutputStream output = null;
Request request = null;
public Response(OutputStream output) {
this.output = output;
}
public void setRequest(Request request){
this.request = request;
}
public void sendStaticResourse() throws IOException{
byte[] b = new byte[2048];
FileInputStream fis = null;
try {
File file = new File(HttpServer.WEB_ROOT,request.getUri());
if(file.exists()){
fis = new FileInputStream(file);
int ch = fis.read(b,0,2048);
while(ch != -1 ){
output.write(b, 0,2048);
}
}else{
String errorMessage = "HTTP/1.1 200 File Not Found\r\n" +
"Content-Type: text/html;charset=ISO-8859-1\r\n" +
"Content-Length: 23\r\n" +
"\r\n" +
"<h1>$)$)404 File not Found</h1>";
System.out.println(errorMessage);
output.write(errorMessage.getBytes());
}
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}finally{
if(fis != null){
fis.close();
}
}
}
}