Http programming (2) using Apache API implementation, apacheapi

Http programming (2) using Apache API implementation, apacheapi

Download the jar package

Import java. io. fileOutputStream; import java. io. IOException; import org. apache. http. httpEntity; import org. apache. http. httpResponse; import org. apache. http. client. httpClient; import org. apache. http. client. methods. httpGet; import org. apache. http. impl. client. defaultHttpClient; import org. apache. http. util. entityUtils;/** classes used for simulated download *: * 1. httpClient: * 2. httpResponse * 3. httpEntity * 4. entityUtils **/publi C class HttpDemo1 {public static void main (String [] args) throws IOException {// HttpClient: the client is created. HttpClient client = new DefaultHttpClient (); // request get: HttpGet String path = "http://www.baidu.com/img/bdlogo.gif"; HttpGet get = new HttpGet (path); // Let the client execute the request. HttpResponse response = client.exe cute (get); // all data is in HttpResponse // 1: response code. Int code = response. getStatusLine (). getStatusCode (); if (code = 200) {// retrieve the returned data. Data is encapsulated into HttpEntity objects. HttpEntity entity = response. getEntity (); // how to obtain data in the HttpEntity object. Byte [] B = EntityUtils. toByteArray (entity); FileOutputStream fos = new FileOutputStream ("e: \ bb.gif"); fos. write (B); fos. flush (); fos. close ();}}}

import java.io.File;import java.io.IOException;import java.nio.charset.Charset;import org.apache.http.HttpEntity;import org.apache.http.HttpResponse;import org.apache.http.client.ClientProtocolException;import org.apache.http.client.HttpClient;import org.apache.http.client.methods.HttpPost;import org.apache.http.entity.mime.FormBodyPart;import org.apache.http.entity.mime.MultipartEntity;import org.apache.http.entity.mime.content.FileBody;import org.apache.http.entity.mime.content.StringBody;import org.apache.http.impl.client.DefaultHttpClient;import org.apache.http.util.EntityUtils;

/*
* Used classes:
* HttpClient
* HttpPost
* FileBody
* FormBodyPart
* MultipartEntity
* HttpResponse
* EntityUtils
*
*/

Public class HttpDemo5 {public static void main (String [] args) throws ClientProtocolException, IOException {// 1: Create an HttpClient object (create a client) HttpClient client = new DefaultHttpClient (); // 2: Create a request method (method in the web) String uri = "http: // localhost: 8080/FileUpload/FileUploadServlet"; HttpPost post = new HttpPost (uri ); // 3: Package the data (File) to be sent // 3.1: Obtain the local file File = new file ("e: \ aa.jpg"); // 3.2: create a FileBody object Body) FileBody fileBody = new FileBody (file); // 3.3: Create a FormBodyPart object (form body part) FormBodyPart part = new FormBodyPart ("form", fileBody); // 4: create a MultipartEntity object. MultipartEntity: multipart entity MultipartEntity entity = new MultipartEntity (); // 5: add the form body to the multipart entity (add file-type data to entity) entity. addPart (part); // 5: Add plain text data to the multi-part entity. addPart ("username", new StringBody ("Haha", "text/html", Charset. forName ("UTF-8"); entity. addPart ("password", new StringBody ("123"); // 6: Set the request object post. setEntity (entity); // 7: Let the client execute the request (a request with data) and get the HttpResponse object (response object) HttpResponse response = client.exe cute (post ); // 8: Get the response code int code = response through the response object. getStatusLine (). getStatusCode (); // 9: if the response code is 200 (success response code), obtain the data returned by the server if (code = 200) {// 9.1: get HttpEntity object (obtained through response) HttpEntity entity2 = response. getEntity (); // 10: Use the EntityUtils tool class to convert the obtained data (entity) to a byte array, any file can save byte [] B = EntityUtils in bytes. toByteArray (entity2); // output content System. out. println (new String (B, "UTF-8 "));}}}