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主要使用Socket请求网络，并完成响应行、响应体、响应头的输出

响应行 = HTTP/1.1 200 OK响应头key = Transfer-Encoding, value = chunkedkey = Server, value = nginxkey = Cache-Control, value = no-cachekey = Connection, value = keep-alivekey = Vary, value = Accept-Encodingkey = P3P, value = CP="IDC DSP COR ADM DEVi TAIi PSA PSD IVAi IVDi CONi HIS OUR IND CNT"key = Date, value = Sun, 05 Aug 2018 09:45:41 GMTkey = Content-Type, value = text/html;charset=UTF-8响应体 = {"message":"ok","nu":"111111","ischeck":"0","condition":"B00","com":"yuantong","status":"200","state":"1","data":[{"time":"2016-01-20 21:35:35","ftime":"2016-01-20 21:35:35","context":"上海市闵行区莘庄公司（13585705701）已收件","location":null}]}

import java.io.IOException;import java.io.InputStream;import java.util.Map;public class MyClass {    public static void main(String[] args) throws IOException {        String path = "http://www.kuaidi100.com/query?type=yuantong&postid=111111";//        String path = "http://www.baidu.com/";        HttpUrl httpUrl = new HttpUrl(path);        Request request = new Request.Builder()                .url(httpUrl)                .addHeader("Host", httpUrl.getHost())                .addHeader("Connection", "keep-alive")                .build();        HttpConnection httpConnection = new HttpConnection(request);        HttpCodec httpCodec = new HttpCodec();        InputStream is = httpConnection.call(httpCodec);        //读取响应行        String responseLine = httpCodec.readLine(is);        System.out.println("responseLine = " + responseLine);        //读取响应头        Map
   
     headers = httpCodec.readHeaders(is);        for (Map.Entry
    
      entry : headers.entrySet()) {            System.out.println("key = " + entry.getKey() + ", value = " + entry.getValue());        }        //响应头分为两种，一种带有Content-Length，会告诉你响应体后面有多少个字节        //一种是Transfer-Encoding：chunked        //会将响应体分成好几段        //例如        //\r\n 响应头和响应体之间的间隔        //10\r\n        //10个字节长度的数据\r\n        //15\r\n        //15个字节长度的数据\r\n        //0\r\n  结束        //\r\n        //读取响应体        int contentLength = -1;        if (headers.containsKey("Content-Length")) {            contentLength = Integer.valueOf(headers.get("Content-Length"));        }        boolean isChunked = false;        if (headers.containsKey("Transfer-Encoding")) {            isChunked = headers.get("Transfer-Encoding").equalsIgnoreCase("chunked");        }        if (contentLength > 0) {            byte[] bytes = httpCodec.readBody(is, contentLength);            System.out.println("Response = " + new String(bytes));        }else if (isChunked) {            String s = httpCodec.readChunked(is);            System.out.println("Response = " + s);        }    }}
    
   

import java.io.IOException;import java.io.InputStream;import java.io.OutputStream;import java.nio.ByteBuffer;import java.util.HashMap;import java.util.Map;class HttpCodec {    private final ByteBuffer byteBuffer;    public HttpCodec() {        byteBuffer = ByteBuffer.allocate(10 * 1024);    }    /**     * 发送请求 拼接请求行、请求头     *     * @param os      输出流     * @param request 请求参数     * @throws IOException     */    public void writeRequest(OutputStream os, Request request) throws IOException {        HttpUrl url = request.url();        StringBuffer sb = new StringBuffer();        //拼接请求行        sb.append(request.method());        sb.append(" ");        sb.append(url.getFile());        sb.append(" ");        sb.append("HTTP/1.1\r\n");        //请求头        Map
   
     headers = request.headers();        for (Map.Entry
    
      entry : headers.entrySet()) {            sb.append(entry.getKey());            sb.append(": ");            sb.append(entry.getValue());            sb.append("\r\n");        }        sb.append("\r\n");        os.write(sb.toString().getBytes("UTF-8"));        os.flush();    }    public String readLine(InputStream is) throws IOException {        byte b;        byteBuffer.clear();        byteBuffer.mark();        //可能读取到一行了        boolean isMabeyEofLine = false;        while ((b = (byte) is.read()) != -1) {            byteBuffer.put(b);            if (b == 13) {                isMabeyEofLine = true;            } else if (isMabeyEofLine) {                //读取到了/n                if (b == 10) {                    //获得一行数据                    byte[] lineBytes = new byte[byteBuffer.position()];                    byteBuffer.reset();                    byteBuffer.get(lineBytes);                    byteBuffer.clear();                    byteBuffer.mark();                    String line = new String(lineBytes);                    return line;                } else {                    isMabeyEofLine = false;                }            }        }        return null;    }    /**     * 读取响应头     *     * @param is     * @return     * @throws IOException     */    public Map
     
       readHeaders(InputStream is) throws IOException {        HashMap
      
        headers = new HashMap<>();        while (true) {            String line = readLine(is);            if (line.equals("\r\n")) {//因为响应头和响应体中间隔了个"\r\n"                break;            }            int index = line.indexOf(":");            if (index > 0) {                String name = line.substring(0, index);                String value = line.substring(index + 2, line.length() - 2);                headers.put(name, value);            }        }        return headers;    }    public byte[] readBody(InputStream is, int len) throws IOException {        byte[] bytes = new byte[len];        int readNum = 0;        while (true) {            readNum += is.read(bytes);            if (readNum == len) {                return bytes;            }        }    }    public String readChunked(InputStream is) throws IOException {        StringBuffer sb = new StringBuffer();        int len = -1;        boolean isEmptyData = false;        while (true) {            if (len < 0) {                String line = readLine(is);                line = line.substring(0, line.length() - 2);//\r\n                len = Integer.valueOf(line, 16);                isEmptyData = len == 0;            } else {                byte[] bytes = readBody(is, len + 2);                sb.append(new String(bytes));                len = -1;                if (isEmptyData) {                    return sb.toString();                }            }        }    }}
      
     
    
   

import java.io.IOException;import java.io.InputStream;import java.io.OutputStream;import java.net.InetSocketAddress;import java.net.Socket;import javax.net.ssl.SSLSocketFactory;public class HttpConnection {    private Request request;    private Socket socket;    private InputStream is;    private OutputStream os;    public HttpConnection(Request request) {        this.request = request;    }    /**     * 连接Socket     */    public InputStream call(HttpCodec httpCodec) throws IOException {        createSocket();        //发送请求        httpCodec.writeRequest(os, request);        return is;    }    public void createSocket() throws IOException {        if (socket != null) {            return;        }        HttpUrl url = request.url();        if (url.getProtocol().equalsIgnoreCase("https")) {            socket = SSLSocketFactory.getDefault().createSocket();        } else {            socket = new Socket();        }        //连接服务器        socket.connect(new InetSocketAddress(url.getHost(), url.getPort()));        is = socket.getInputStream();        os = socket.getOutputStream();    }}

import java.net.MalformedURLException;import java.net.URL;public class HttpUrl {    private String file;    private int port;    private final String protocol;    private final String host;    public String getFile() {        return file;    }    public void setFile(String file) {        this.file = file;    }    public int getPort() {        return port;    }    public void setPort(int port) {        this.port = port;    }    public String getProtocol() {        return protocol;    }    public String getHost() {        return host;    }    public HttpUrl(String url) throws MalformedURLException {        URL url1 = new URL(url);        host = url1.getHost();        file = url1.getFile();        file = isEmpty(file) ? "/" : file;        protocol = url1.getProtocol();        port = url1.getPort();        port = port == -1 ? url1.getDefaultPort() : port;    }    private boolean isEmpty(String file) {        if (file.length() == 0) {            return true;        }        return false;    }}

import java.util.HashMap;import java.util.Map;public class Request {    HttpUrl url;    Map
   
     headers = new HashMap<>();    String method;    public Request(Builder builder) {        this.url = builder.url;        this.method = builder.method;        this.headers = builder.headers;    }    public String method() {        return method;    }    public HttpUrl url() {        return url;    }    public Map
    
      headers() {        return headers;    }    public final static class Builder {        HttpUrl url;        Map
     
       headers = new HashMap<>();        String method;        public Builder() {            this.method = "GET";        }        public Builder url(HttpUrl url) {            this.url = url;            return this;        }        public Builder addHeader(String name, String value) {            headers.put(name, value);            return this;        }        public Request build() {            if (url == null) {                throw new IllegalStateException("url is null");            }            return new Request(this);        }    }}
     
    
   

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