java 常见几种发送http请求案例
直接换成CloseableHttpClient还不行,需要这样使用CloseableHttpClient httpClient = HttpClientBuilder.create().build();import org.apache.http.impl.client.DefaultHttpClient;
已经不再推荐使用有需要同的同学把这个类替换成import org.apache.http.impl.client.CloseableHttpClient;使用就可以了
- 原文:http://blog.csdn.net/u010197591/article/details/51441399
- import java.io.FileOutputStream;
- import java.io.IOException;
- import java.io.InputStream;
- import java.io.InputStreamReader;
- import java.io.OutputStreamWriter;
- import java.io.UnsupportedEncodingException;
- import java.net.HttpURLConnection;
- import java.net.Socket;
- import java.net.URL;
- import java.net.URLConnection;
- import java.net.URLEncoder;
- import java.util.ArrayList;
- import java.util.HashMap;
- import java.util.Iterator;
- import java.util.List;
- import java.util.Map;
- import java.util.Map.Entry;
- import org.apache.http.HttpResponse;
- import org.apache.http.NameValuePair;
- import org.apache.http.client.HttpClient;
- import org.apache.http.client.entity.UrlEncodedFormEntity;
- import org.apache.http.client.methods.HttpGet;
- import org.apache.http.client.methods.HttpPost;
- import org.apache.http.impl.client.DefaultHttpClient;
- import org.apache.http.message.BasicNameValuePair;
- /**
- * @Description:发送http请求帮助类
- * @author:liuyc
- * @time:2016年5月17日 下午3:25:32
- */
- public class HttpClientHelper {
- /**
- * @Description:使用HttpURLConnection发送post请求
- * @author:liuyc
- * @time:2016年5月17日 下午3:26:07
- */
- public static String sendPost(String urlParam, Map<String, Object> params, String charset) {
- StringBuffer resultBuffer = null;
- // 构建请求参数
- StringBuffer sbParams = new StringBuffer();
- if (params != null && params.size() > 0) {
- for (Entry<String, Object> e : params.entrySet()) {
- sbParams.append(e.getKey());
- sbParams.append("=");
- sbParams.append(e.getValue());
- sbParams.append("&");
- }
- }
- HttpURLConnection con = null;
- OutputStreamWriter osw = null;
- BufferedReader br = null;
- // 发送请求
- try {
- URL url = new URL(urlParam);
- con = (HttpURLConnection) url.openConnection();
- con.setRequestMethod("POST");
- con.setDoOutput(true);
- con.setDoInput(true);
- con.setUseCaches(false);
- con.setRequestProperty("Content-Type", "application/x-www-form-urlencoded");
- if (sbParams != null && sbParams.length() > 0) {
- osw = new OutputStreamWriter(con.getOutputStream(), charset);
- osw.write(sbParams.substring(0, sbParams.length() - 1));
- osw.flush();
- }
- // 读取返回内容
- resultBuffer = new StringBuffer();
- int contentLength = Integer.parseInt(con.getHeaderField("Content-Length"));
- if (contentLength > 0) {
- br = new BufferedReader(new InputStreamReader(con.getInputStream(), charset));
- String temp;
- while ((temp = br.readLine()) != null) {
- resultBuffer.append(temp);
- }
- }
- } catch (Exception e) {
- throw new RuntimeException(e);
- } finally {
- if (osw != null) {
- try {
- osw.close();
- } catch (IOException e) {
- osw = null;
- throw new RuntimeException(e);
- } finally {
- if (con != null) {
- con.disconnect();
- con = null;
- }
- }
- }
- if (br != null) {
- try {
- br.close();
- } catch (IOException e) {
- br = null;
- throw new RuntimeException(e);
- } finally {
- if (con != null) {
- con.disconnect();
- con = null;
- }
- }
- }
- }
- return resultBuffer.toString();
- }
- /**
- * @Description:使用URLConnection发送post
- * @author:liuyc
- * @time:2016年5月17日 下午3:26:52
- */
- public static String sendPost2(String urlParam, Map<String, Object> params, String charset) {
- StringBuffer resultBuffer = null;
- // 构建请求参数
- StringBuffer sbParams = new StringBuffer();
- if (params != null && params.size() > 0) {
- for (Entry<String, Object> e : params.entrySet()) {
- sbParams.append(e.getKey());
- sbParams.append("=");
- sbParams.append(e.getValue());
- sbParams.append("&");
- }
- }
- URLConnection con = null;
- OutputStreamWriter osw = null;
- BufferedReader br = null;
- try {
- URL realUrl = new URL(urlParam);
- // 打开和URL之间的连接
- con = realUrl.openConnection();
- // 设置通用的请求属性
- con.setRequestProperty("accept", "*/*");
- con.setRequestProperty("connection", "Keep-Alive");
- con.setRequestProperty("Content-Type", "application/x-www-form-urlencoded");
- con.setRequestProperty("user-agent", "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1;SV1)");
- // 发送POST请求必须设置如下两行
- con.setDoOutput(true);
- con.setDoInput(true);
- // 获取URLConnection对象对应的输出流
- osw = new OutputStreamWriter(con.getOutputStream(), charset);
- if (sbParams != null && sbParams.length() > 0) {
- // 发送请求参数
- osw.write(sbParams.substring(0, sbParams.length() - 1));
- // flush输出流的缓冲
- osw.flush();
- }
- // 定义BufferedReader输入流来读取URL的响应
- resultBuffer = new StringBuffer();
- int contentLength = Integer.parseInt(con.getHeaderField("Content-Length"));
- if (contentLength > 0) {
- br = new BufferedReader(new InputStreamReader(con.getInputStream(), charset));
- String temp;
- while ((temp = br.readLine()) != null) {
- resultBuffer.append(temp);
- }
- }
- } catch (Exception e) {
- throw new RuntimeException(e);
- } finally {
- if (osw != null) {
- try {
- osw.close();
- } catch (IOException e) {
- osw = null;
- throw new RuntimeException(e);
- }
- }
- if (br != null) {
- try {
- br.close();
- } catch (IOException e) {
- br = null;
- throw new RuntimeException(e);
- }
- }
- }
- return resultBuffer.toString();
- }
- /**
- * @Description:发送get请求保存下载文件
- * @author:liuyc
- * @time:2016年5月17日 下午3:27:29
- */
- public static void sendGetAndSaveFile(String urlParam, Map<String, Object> params, String fileSavePath) {
- // 构建请求参数
- StringBuffer sbParams = new StringBuffer();
- if (params != null && params.size() > 0) {
- for (Entry<String, Object> entry : params.entrySet()) {
- sbParams.append(entry.getKey());
- sbParams.append("=");
- sbParams.append(entry.getValue());
- sbParams.append("&");
- }
- }
- HttpURLConnection con = null;
- BufferedReader br = null;
- FileOutputStream os = null;
- try {
- URL url = null;
- if (sbParams != null && sbParams.length() > 0) {
- url = new URL(urlParam + "?" + sbParams.substring(0, sbParams.length() - 1));
- } else {
- url = new URL(urlParam);
- }
- con = (HttpURLConnection) url.openConnection();
- con.setRequestProperty("Content-Type", "application/x-www-form-urlencoded");
- con.connect();
- InputStream is = con.getInputStream();
- os = new FileOutputStream(fileSavePath);
- byte buf[] = new byte[1024];
- int count = 0;
- while ((count = is.read(buf)) != -1) {
- os.write(buf, 0, count);
- }
- os.flush();
- } catch (Exception e) {
- throw new RuntimeException(e);
- } finally {
- if (os != null) {
- try {
- os.close();
- } catch (IOException e) {
- os = null;
- throw new RuntimeException(e);
- } finally {
- if (con != null) {
- con.disconnect();
- con = null;
- }
- }
- }
- if (br != null) {
- try {
- br.close();
- } catch (IOException e) {
- br = null;
- throw new RuntimeException(e);
- } finally {
- if (con != null) {
- con.disconnect();
- con = null;
- }
- }
- }
- }
- }
- /**
- * @Description:使用HttpURLConnection发送get请求
- * @author:liuyc
- * @time:2016年5月17日 下午3:27:29
- */
- public static String sendGet(String urlParam, Map<String, Object> params, String charset) {
- StringBuffer resultBuffer = null;
- // 构建请求参数
- StringBuffer sbParams = new StringBuffer();
- if (params != null && params.size() > 0) {
- for (Entry<String, Object> entry : params.entrySet()) {
- sbParams.append(entry.getKey());
- sbParams.append("=");
- sbParams.append(entry.getValue());
- sbParams.append("&");
- }
- }
- HttpURLConnection con = null;
- BufferedReader br = null;
- try {
- URL url = null;
- if (sbParams != null && sbParams.length() > 0) {
- url = new URL(urlParam + "?" + sbParams.substring(0, sbParams.length() - 1));
- } else {
- url = new URL(urlParam);
- }
- con = (HttpURLConnection) url.openConnection();
- con.setRequestProperty("Content-Type", "application/x-www-form-urlencoded");
- con.connect();
- resultBuffer = new StringBuffer();
- br = new BufferedReader(new InputStreamReader(con.getInputStream(), charset));
- String temp;
- while ((temp = br.readLine()) != null) {
- resultBuffer.append(temp);
- }
- } catch (Exception e) {
- throw new RuntimeException(e);
- } finally {
- if (br != null) {
- try {
- br.close();
- } catch (IOException e) {
- br = null;
- throw new RuntimeException(e);
- } finally {
- if (con != null) {
- con.disconnect();
- con = null;
- }
- }
- }
- }
- return resultBuffer.toString();
- }
- /**
- * @Description:使用URLConnection发送get请求
- * @author:liuyc
- * @time:2016年5月17日 下午3:27:58
- */
- public static String sendGet2(String urlParam, Map<String, Object> params, String charset) {
- StringBuffer resultBuffer = null;
- // 构建请求参数
- StringBuffer sbParams = new StringBuffer();
- if (params != null && params.size() > 0) {
- for (Entry<String, Object> entry : params.entrySet()) {
- sbParams.append(entry.getKey());
- sbParams.append("=");
- sbParams.append(entry.getValue());
- sbParams.append("&");
- }
- }
- BufferedReader br = null;
- try {
- URL url = null;
- if (sbParams != null && sbParams.length() > 0) {
- url = new URL(urlParam + "?" + sbParams.substring(0, sbParams.length() - 1));
- } else {
- url = new URL(urlParam);
- }
- URLConnection con = url.openConnection();
- // 设置请求属性
- con.setRequestProperty("accept", "*/*");
- con.setRequestProperty("connection", "Keep-Alive");
- con.setRequestProperty("Content-Type", "application/x-www-form-urlencoded");
- con.setRequestProperty("user-agent", "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1;SV1)");
- // 建立连接
- con.connect();
- resultBuffer = new StringBuffer();
- br = new BufferedReader(new InputStreamReader(con.getInputStream(), charset));
- String temp;
- while ((temp = br.readLine()) != null) {
- resultBuffer.append(temp);
- }
- } catch (Exception e) {
- throw new RuntimeException(e);
- } finally {
- if (br != null) {
- try {
- br.close();
- } catch (IOException e) {
- br = null;
- throw new RuntimeException(e);
- }
- }
- }
- return resultBuffer.toString();
- }
- /**
- * @Description:使用HttpClient发送post请求
- * @author:liuyc
- * @time:2016年5月17日 下午3:28:23
- */
- public static String httpClientPost(String urlParam, Map<String, Object> params, String charset) {
- StringBuffer resultBuffer = null;
- HttpClient client = new DefaultHttpClient();
- HttpPost httpPost = new HttpPost(urlParam);
- // 构建请求参数
- List<NameValuePair> list = new ArrayList<NameValuePair>();
- Iterator<Entry<String, Object>> iterator = params.entrySet().iterator();
- while (iterator.hasNext()) {
- Entry<String, Object> elem = iterator.next();
- list.add(new BasicNameValuePair(elem.getKey(), String.valueOf(elem.getValue())));
- }
- BufferedReader br = null;
- try {
- if (list.size() > 0) {
- UrlEncodedFormEntity entity = new UrlEncodedFormEntity(list, charset);
- httpPost.setEntity(entity);
- }
- HttpResponse response = client.execute(httpPost);
- // 读取服务器响应数据
- resultBuffer = new StringBuffer();
- br = new BufferedReader(new InputStreamReader(response.getEntity().getContent()));
- String temp;
- while ((temp = br.readLine()) != null) {
- resultBuffer.append(temp);
- }
- } catch (Exception e) {
- throw new RuntimeException(e);
- } finally {
- if (br != null) {
- try {
- br.close();
- } catch (IOException e) {
- br = null;
- throw new RuntimeException(e);
- }
- }
- }
- return resultBuffer.toString();
- }
- /**
- * @Description:使用HttpClient发送get请求
- * @author:liuyc
- * @time:2016年5月17日 下午3:28:56
- */
- public static String httpClientGet(String urlParam, Map<String, Object> params, String charset) {
- StringBuffer resultBuffer = null;
- HttpClient client = new DefaultHttpClient();
- BufferedReader br = null;
- // 构建请求参数
- StringBuffer sbParams = new StringBuffer();
- if (params != null && params.size() > 0) {
- for (Entry<String, Object> entry : params.entrySet()) {
- sbParams.append(entry.getKey());
- sbParams.append("=");
- try {
- sbParams.append(URLEncoder.encode(String.valueOf(entry.getValue()), charset));
- } catch (UnsupportedEncodingException e) {
- throw new RuntimeException(e);
- }
- sbParams.append("&");
- }
- }
- if (sbParams != null && sbParams.length() > 0) {
- urlParam = urlParam + "?" + sbParams.substring(0, sbParams.length() - 1);
- }
- HttpGet httpGet = new HttpGet(urlParam);
- try {
- HttpResponse response = client.execute(httpGet);
- // 读取服务器响应数据
- br = new BufferedReader(new InputStreamReader(response.getEntity().getContent()));
- String temp;
- resultBuffer = new StringBuffer();
- while ((temp = br.readLine()) != null) {
- resultBuffer.append(temp);
- }
- } catch (Exception e) {
- throw new RuntimeException(e);
- } finally {
- if (br != null) {
- try {
- br.close();
- } catch (IOException e) {
- br = null;
- throw new RuntimeException(e);
- }
- }
- }
- return resultBuffer.toString();
- }
- /**
- * @Description:使用socket发送post请求
- * @author:liuyc
- * @time:2016年5月18日 上午9:26:22
- */
- public static String sendSocketPost(String urlParam, Map<String, Object> params, String charset) {
- String result = "";
- // 构建请求参数
- StringBuffer sbParams = new StringBuffer();
- if (params != null && params.size() > 0) {
- for (Entry<String, Object> entry : params.entrySet()) {
- sbParams.append(entry.getKey());
- sbParams.append("=");
- sbParams.append(entry.getValue());
- sbParams.append("&");
- }
- }
- Socket socket = null;
- OutputStreamWriter osw = null;
- InputStream is = null;
- try {
- URL url = new URL(urlParam);
- String host = url.getHost();
- int port = url.getPort();
- if (-1 == port) {
- port = 80;
- }
- String path = url.getPath();
- socket = new Socket(host, port);
- StringBuffer sb = new StringBuffer();
- sb.append("POST " + path + " HTTP/1.1 ");
- sb.append("Host: " + host + " ");
- sb.append("Connection: Keep-Alive ");
- sb.append("Content-Type: application/x-www-form-urlencoded; charset=utf-8 ");
- sb.append("Content-Length: ").append(sb.toString().getBytes().length).append(" ");
- // 这里一个回车换行,表示消息头写完,不然服务器会继续等待
- sb.append(" ");
- if (sbParams != null && sbParams.length() > 0) {
- sb.append(sbParams.substring(0, sbParams.length() - 1));
- }
- osw = new OutputStreamWriter(socket.getOutputStream());
- osw.write(sb.toString());
- osw.flush();
- is = socket.getInputStream();
- String line = null;
- // 服务器响应体数据长度
- int contentLength = 0;
- // 读取http响应头部信息
- do {
- line = readLine(is, 0, charset);
- if (line.startsWith("Content-Length")) {
- // 拿到响应体内容长度
- contentLength = Integer.parseInt(line.split(":")[1].trim());
- }
- // 如果遇到了一个单独的回车换行,则表示请求头结束
- } while (!line.equals(" "));
- // 读取出响应体数据(就是你要的数据)
- result = readLine(is, contentLength, charset);
- } catch (Exception e) {
- throw new RuntimeException(e);
- } finally {
- if (osw != null) {
- try {
- osw.close();
- } catch (IOException e) {
- osw = null;
- throw new RuntimeException(e);
- } finally {
- if (socket != null) {
- try {
- socket.close();
- } catch (IOException e) {
- socket = null;
- throw new RuntimeException(e);
- }
- }
- }
- }
- if (is != null) {
- try {
- is.close();
- } catch (IOException e) {
- is = null;
- throw new RuntimeException(e);
- } finally {
- if (socket != null) {
- try {
- socket.close();
- } catch (IOException e) {
- socket = null;
- throw new RuntimeException(e);
- }
- }
- }
- }
- }
- return result;
- }
- /**
- * @Description:使用socket发送get请求
- * @author:liuyc
- * @time:2016年5月18日 上午9:27:18
- */
- public static String sendSocketGet(String urlParam, Map<String, Object> params, String charset) {
- String result = "";
- // 构建请求参数
- StringBuffer sbParams = new StringBuffer();
- if (params != null && params.size() > 0) {
- for (Entry<String, Object> entry : params.entrySet()) {
- sbParams.append(entry.getKey());
- sbParams.append("=");
- sbParams.append(entry.getValue());
- sbParams.append("&");
- }
- }
- Socket socket = null;
- OutputStreamWriter osw = null;
- InputStream is = null;
- try {
- URL url = new URL(urlParam);
- String host = url.getHost();
- int port = url.getPort();
- if (-1 == port) {
- port = 80;
- }
- String path = url.getPath();
- socket = new Socket(host, port);
- StringBuffer sb = new StringBuffer();
- sb.append("GET " + path + " HTTP/1.1 ");
- sb.append("Host: " + host + " ");
- sb.append("Connection: Keep-Alive ");
- sb.append("Content-Type: application/x-www-form-urlencoded; charset=utf-8 ");
- sb.append("Content-Length: ").append(sb.toString().getBytes().length).append(" ");
- // 这里一个回车换行,表示消息头写完,不然服务器会继续等待
- sb.append(" ");
- if (sbParams != null && sbParams.length() > 0) {
- sb.append(sbParams.substring(0, sbParams.length() - 1));
- }
- osw = new OutputStreamWriter(socket.getOutputStream());
- osw.write(sb.toString());
- osw.flush();
- is = socket.getInputStream();
- String line = null;
- // 服务器响应体数据长度
- int contentLength = 0;
- // 读取http响应头部信息
- do {
- line = readLine(is, 0, charset);
- if (line.startsWith("Content-Length")) {
- // 拿到响应体内容长度
- contentLength = Integer.parseInt(line.split(":")[1].trim());
- }
- // 如果遇到了一个单独的回车换行,则表示请求头结束
- } while (!line.equals(" "));
- // 读取出响应体数据(就是你要的数据)
- result = readLine(is, contentLength, charset);
- } catch (Exception e) {
- throw new RuntimeException(e);
- } finally {
- if (osw != null) {
- try {
- osw.close();
- } catch (IOException e) {
- osw = null;
- throw new RuntimeException(e);
- } finally {
- if (socket != null) {
- try {
- socket.close();
- } catch (IOException e) {
- socket = null;
- throw new RuntimeException(e);
- }
- }
- }
- }
- if (is != null) {
- try {
- is.close();
- } catch (IOException e) {
- is = null;
- throw new RuntimeException(e);
- } finally {
- if (socket != null) {
- try {
- socket.close();
- } catch (IOException e) {
- socket = null;
- throw new RuntimeException(e);
- }
- }
- }
- }
- }
- return result;
- }
- /**
- * @Description:读取一行数据,contentLe内容长度为0时,读取响应头信息,不为0时读正文
- * @time:2016年5月17日 下午6:11:07
- */
- private static String readLine(InputStream is, int contentLength, String charset) throws IOException {
- List<Byte> lineByte = new ArrayList<Byte>();
- byte tempByte;
- int cumsum = 0;
- if (contentLength != 0) {
- do {
- tempByte = (byte) is.read();
- lineByte.add(Byte.valueOf(tempByte));
- cumsum++;
- } while (cumsum < contentLength);// cumsum等于contentLength表示已读完
- } else {
- do {
- tempByte = (byte) is.read();
- lineByte.add(Byte.valueOf(tempByte));
- } while (tempByte != 10);// 换行符的ascii码值为10
- }
- byte[] resutlBytes = new byte[lineByte.size()];
- for (int i = 0; i < lineByte.size(); i++) {
- resutlBytes[i] = (lineByte.get(i)).byteValue();
- }
- return new String(resutlBytes, charset);
- }
- }
以上4种分别可发送get和post请求的方法,第1种:HttpURLConnection、第2种:URLConnection、第3种:HttpClient、第4种:Socket,朋友们要注意的是,使用第3种HttpClient时需要依赖于三个jar包,分别是:apache-httpcomponents-httpclient.jar、commons-logging-1.0.4.jar、httpcore-4.1.1.jar。好了就到这里吧,有问题记得留言哦