HttpClient/ HttpUrlConnection/UrlConnection

HttpUrlConnection:sun公司封装的网络连接

doGet
doPost

HttpClient：Apache使用HttpURLConnection封装的类

HttpClientdoGet
HttpClientdoPost

常用编码转换

// 设置接受的数据类型httpConnection.setRequestProperty("Accept-Charset", "utf-8");// 设置可以接受序列化的java对象             httpConnection.setRequestProperty("Content-Type", "application/x-www-form-urlencoded");

deGet方法测试

JButton btnNewButton = new JButton("doGet方法测试");        btnNewButton.addActionListener(new ActionListener() {            public void actionPerformed(ActionEvent arg0) {                String urlString="http://localhost:8080/MyServiceTest/MyTestServerlet?username=zhangsan&password=123456";                try {                    URL url=new URL(urlString);//生成URL                    URLConnection connect=url.openConnection();//打开url链接                    //强制转型成httpurlconnection                    HttpURLConnection httpConnection=(HttpURLConnection)connect;                    //设置请求方法                    httpConnection.setRequestMethod("GET");                    //设置编码格式                    // 设置接受的数据类型                    httpConnection.setRequestProperty("Accept-Charset", "utf-8");                    // 设置可以接受序列化的java对象                    httpConnection.setRequestProperty("Content-Type", "application/x-www-form-urlencoded");                    int code=httpConnection.getResponseCode();                    System.out.println("状态码："+code);                    if(code==HttpURLConnection.HTTP_OK){                        InputStream is=httpConnection.getInputStream();                        BufferedReader br=new BufferedReader(new InputStreamReader(is));                        String line=br.readLine();                        while (line!=null){                            System.out.println(line);                            line=br.readLine();                        }                    }

#

1生成URL ——->URL url=new URL(urlString);
2开url链接——–>URLConnection connect=url.openConnection();
3强制转型httpurlconnection——->HttpURLConnection httpConnection=(HttpURLConnection)connect;

DoPost

//设置请求方法
httpConnection.setRequestMethod(“POST”);
//设置可以读取服务器返回的内容默认true
httpConnection.setDoInput(true);
//设置哭护短可以给服务器提交数据，默认为false但POST必须设置true
httpConnection.setDoOutput(true);
//POST方法不允许使用缓存
httpConnection.setUseCaches(false);
String params=”username=zhangsan&password=lisi”;
httpConnection.getOutputStream().write(params.getBytes());

public void actionPerformed(ActionEvent arg0) {                String urlString="http://localhost:8080/MyServiceTest/MyTestServerlet?username=zhangsan&password=123456";                try {                    URL url=new URL(urlString);//生成URL                    URLConnection connect=url.openConnection();//打开url链接                    //强制转型成httpurlconnection                    HttpURLConnection httpConnection=(HttpURLConnection)connect;                    //设置读取时间超时                    httpConnection.setReadTimeout(30000);                    //设置链接超时时间                    httpConnection.setConnectTimeout(30000);                    //设置编码格式                    // 设置接受的数据类型                    httpConnection.setRequestProperty("Accept-Charset", "utf-8");                    // 设置可以接受序列化的java对象                    httpConnection.setRequestProperty("Content-Type", "application/x-www-form-urlencoded");                    //设置请求方法                    httpConnection.setRequestMethod("POST");                    //设置可以读取服务器返回的内容默认true                    httpConnection.setDoInput(true);                    //设置哭护短可以给服务器提交数据，默认为false但POST必须设置true                    httpConnection.setDoOutput(true);                    //POST方法不允许使用缓存                    httpConnection.setUseCaches(false);                    String params="username=zhangsan&password=lisi";                    httpConnection.getOutputStream().write(params.getBytes());                    int code=httpConnection.getResponseCode();                    System.out.println("状态码："+code);                    if(code==HttpURLConnection.HTTP_OK){                        InputStream is=httpConnection.getInputStream();                        BufferedReader br=new BufferedReader(new InputStreamReader(is));                        String line=br.readLine();                        while (line!=null){                            System.out.println(line);                            line=br.readLine();                        }                    }2                } catch (MalformedURLException e) {                    e.printStackTrace();                } catch (ConnectException e) {                    System.out.println("服务器拒绝链接");                    e.printStackTrace();                }catch ( SocketTimeoutException e) {                    System.out.println("网络连接超时");                    e.printStackTrace();                }catch (IOException e) {                    // TODO Auto-generated catch block                    e.printStackTrace();                }

HttpClientDoGet

JButton btnNewButton = new JButton("HttpClientDoGet");        btnNewButton.addActionListener(new ActionListener() {            public void actionPerformed(ActionEvent e) {                String urlString="http://localhost:8080/MyServiceTest/MyTestServerlet?username=zhangsan&password=123456";                HttpClientBuilder builder=HttpClientBuilder.create();                builder.setConnectionTimeToLive(3000, TimeUnit.MILLISECONDS);                //生成client的buidler                HttpClient client=builder.build();//生成client                HttpGet get=new HttpGet(urlString);//设置为get方法                get.setHeader("Content-Type", "application/x-www-form-urlencoded; charset=UTF-8");                //设置服务器接收后数据的读取方式为utf8                try {                    HttpResponse response=client.execute(get);//执行get方法得到服务器的返回的所有数据都在response中                    StatusLine statusLine=response.getStatusLine();//httpClient访问服务器返回的表头，包含http状态码                    int code=statusLine.getStatusCode();//得到状态码                    if(code==HttpURLConnection.HTTP_OK){                        HttpEntity entity=response.getEntity();//得到数据的实体                        InputStream is=entity.getContent();//得到输入流                        BufferedReader br=new BufferedReader(new InputStreamReader(is));                        String line=br.readLine();                        while(line!=null){                            System.out.println(line);                            line=br.readLine();                        }                    }                } catch (ClientProtocolException e1) {                    // TODO Auto-generated catch block                    e1.printStackTrace();                } catch (IOException e1) {                    // TODO Auto-generated catch block                    e1.printStackTrace();                }            }        });

HttpClientDoPOST

public void actionPerformed(ActionEvent arg0) {                String urlString = "http://localhost:8080/MyServiceTest/MyTestServerlet";                HttpClientBuilder builder = HttpClientBuilder.create();                builder.setConnectionTimeToLive(3000, TimeUnit.MICROSECONDS);                // 生成client的builder                HttpClient client = builder.build();                HttpPost post = new HttpPost(urlString);// 设置为get方法                NameValuePair pair1=new BasicNameValuePair("username","张三");                NameValuePair pair2=new BasicNameValuePair("password","123456");                ArrayList<NameValuePair>params=new ArrayList<>();                params.add(pair1);                params.add(pair2);                try {                    post.setEntity(new UrlEncodedFormEntity(params ,"UTF-8"));                    post.setHeader("Content-Type", "application/x-www-form-urlencoded; charset=UTF-8");                    HttpResponse response =client.execute(post);                int code =response.getStatusLine().getStatusCode();                if(code==200){                    HttpEntity entity=response.getEntity();                    InputStream is=entity.getContent();                    BufferedReader br= new BufferedReader(new InputStreamReader(is));                    String line =br.readLine();                    while(line!=null){                        System.out.println(line);                        line=br.readLine();                    }                }