手写服务器




    
        login
        imooc.study.server.LoginServlet
    

    
        login
        /login
        /g
    

    
        register
        imooc.study.server.RegisterServlet
    


    
        register
        /register
        /r
    

package imooc.study.server;

import javax.xml.parsers.SAXParser;
import javax.xml.parsers.SAXParserFactory;
import java.util.List;

import static java.lang.Thread.currentThread;

public class XMLWeb {
    public static void main(String[] args) throws Exception {
        SAXParserFactory factory = SAXParserFactory.newInstance();
        SAXParser saxParser = factory.newSAXParser();
        WebHandler handler = new WebHandler();
        saxParser.parse(currentThread().getContextClassLoader().getResourceAsStream("web.xml"), handler);
        List entityList = handler.getEntityList();
        System.out.println(entityList);
        List mappingList = handler.getMappingList();
        System.out.println(mappingList);

        WebContext webContext = new WebContext(entityList, mappingList);
        String className = webContext.getClz("/xxx");
        System.out.println(className);

        //根据反射 实例化对象
        Class forName = Class.forName(className);
        Servlet o = (Servlet) forName.newInstance();
        o.service();
    }


}

package imooc.study.server;

import org.xml.sax.Attributes;
import org.xml.sax.SAXException;
import org.xml.sax.helpers.DefaultHandler;

import java.util.ArrayList;
import java.util.List;
import java.util.Objects;

class WebHandler extends DefaultHandler {

    private Entity entity;
    private Mapping mapping;

    private List entityList;
    private List mappingList;
    private String tag;
    private boolean isEntity;
    private boolean isMapping;

    public List getEntityList() {
        return entityList;
    }

    public List getMappingList() {
        return mappingList;
    }

    @Override
    public void startDocument() throws SAXException {
        entityList = new ArrayList<>();
        mappingList = new ArrayList<>();
        isEntity = false;
        isMapping = false;
    }

    @Override
    public void startElement(String uri, String localName, String qName, Attributes attributes) throws SAXException {
//        System.out.println();
//        System.out.println("start-->" + qName);
        tag = qName;
        if (qName.equals("servlet")) {
            entity = new Entity();
            isEntity = true;
        } else if (qName.equals("servlet-mapping")) {
            mapping = new Mapping();
            isMapping = true;
        }
    }

    @Override
    public void endElement(String uri, String localName, String qName) throws SAXException {
//        System.out.println();
//        System.out.println("end-->" + qName);
        if (qName.equals("servlet")) {
            entityList.add(entity);
            isEntity = false;
        } else if (qName.equals("servlet-mapping")) {
            mappingList.add(mapping);
            isMapping = false;
        }
        tag = null;
    }

    @Override
    public void endDocument() throws SAXException {
//        System.out.println(list);
//        System.out.println("stop-----");
//        System.out.println("============");
    }

    @Override
    public void characters(char[] ch, int start, int length) throws SAXException {
        String content = new String(ch, start, length);
//        System.out.println("content--->" + content);
//
//        if (Objects.equals(tag, "name")) {
//            person.setName(content);
//        } else if (Objects.equals(tag, "age")) {
//            person.setAge(Integer.parseInt(content));
//        }

        if (isEntity) {
            if (Objects.equals(tag, "servlet-name")) {
                entity.setName(content);
            } else if (Objects.equals(tag, "servlet-class")) {
                entity.setClz(content);
            }
        } else if (isMapping) {
            if (Objects.equals(tag, "servlet-name")) {
                mapping.setName(content);
            } else if (Objects.equals(tag, "url-pattern")) {
                mapping.addPattern(content);
            }
        }
    }
}

package imooc.study.server;

import java.util.HashMap;
import java.util.List;
import java.util.Map;

public class WebContext {
    //k -> servlet-name v -> servlet-class
    private Map entityMap;
    //k-> url-pattern v -> servlet-name
    private Map mapingMap;

    public WebContext() {
    }

    public WebContext(List entityList, List mapingList) {

        entityMap = new HashMap<>();
        mapingMap = new HashMap<>();

        for (Entity entity : entityList) {
            entityMap.put(entity.getName(), entity.getClz());
        }

        for (Mapping mapping : mapingList) {
            for (String pattern : mapping.getPattern()) {
                mapingMap.put(pattern, mapping.getName());
            }
        }

    }

    public String getClz(String pattern) {
        return entityMap.get(mapingMap.get(pattern));
    }
}

package imooc.study.server;

public interface Servlet {
    void service();
}

package imooc.study.server;

public class RegisterServlet implements Servlet {
    @Override
    public void service() {
        System.out.println("RegisterServlet");
    }
}

package imooc.study.server;

public class LoginServlet implements Servlet {
    @Override
    public void service() {
        System.out.println("LoginServlet");
    }
}

package imooc.study.server;

import java.util.HashSet;
import java.util.Set;

public class Mapping {
    private String name;
    private Set pattern;

    public Mapping() {
        pattern = new HashSet<>();
    }

    public Mapping(String name) {
        this.name = name;
    }

    public void addPattern(String parttern) {
        pattern.add(parttern);
    }

    public void setName(String name) {
        this.name = name;
    }

    public String getName() {
        return name;
    }

    public Set getPattern() {
        return pattern;
    }

    @Override
    public String toString() {
        return "Mapping{" +
                "name='" + name + '\'' +
                ", pattern=" + pattern +
                '}';
    }
}

package imooc.study.server;

public class Entity {
    private String name;
    private String clz;

    public Entity() {
    }

    public Entity(String name, String clz) {
        this.name = name;
        this.clz = clz;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public void setClz(String clz) {
        this.clz = clz;
    }

    public String getClz() {
        return clz;
    }

    @Override
    public String toString() {
        return "Entity{" +
                "name='" + name + '\'' +
                ", clz='" + clz + '\'' +
                '}';
    }
}

package imooc.study.server.serverdemo;

import java.io.*;
import java.net.ServerSocket;
import java.net.Socket;
import java.util.Date;

public class Server {

    private ServerSocket serverSocket;

    public static void main(String[] args) {
        Server server = new Server();
        server.start();
    }

    public void start() {
        try {
            serverSocket = new ServerSocket(8000);
            receive();
        } catch (IOException e) {
            e.printStackTrace();
            System.out.println("server is error");
        }
    }

    public void receive() {
        try {
            Socket accept = serverSocket.accept();
            InputStream inputStream = accept.getInputStream();
//            BufferedReader reader = new BufferedReader(new InputStreamReader(inputStream));
//            String data;
//            while ((data = reader.readLine()) != null) {
//                System.out.println(data);
//            }

            byte[] data = new byte[1024*1024];
            int len = inputStream.read(data);

            String header = new String(data, 0, len);
            System.out.println(header);

            OutputStream out = accept.getOutputStream();
//            BufferedWriter writer = new BufferedWriter(new OutputStreamWriter(outputStream));
//            writer.write("HTTP/1.1 200 OK\r\n");
//            writer.write("Content‐Type:text/html\r\n");
//            writer.write(String.format("Date:%s\r\n", new Date()));
//            writer.write("\r\n");
//            writer.write("

hello

"); out.write("HTTP/1.1 200 OK\r\n".getBytes()); out.write("Content‐Type:text/html\r\n".getBytes()); out.write(String.format("Date:%s\r\n", new Date()).getBytes()); out.write("\r\n".getBytes()); FileInputStream fileInputStream = new FileInputStream("src/main/resources/login.html"); int read; while ((read = fileInputStream.read()) != -1) { out.write(read); } // out.write("

hello

".getBytes()); out.flush(); } catch (IOException e) { e.printStackTrace(); System.out.println("client connect error"); } } public void stop() { } }

你可能感兴趣的:(手写服务器)