以下代码包括最基本的GET、POST、JSON参数的POST方式的请求。(相当于POSTMAN中使用raw编写的参数)
package com.chinecredit.eccis.utils;
import java.io.IOException;
import java.io.UnsupportedEncodingException;
import java.util.ArrayList;
import java.util.List;
import java.util.Map;
import java.util.Set;
import org.apache.http.HttpEntity;
import org.apache.http.HttpStatus;
import org.apache.http.NameValuePair;
import org.apache.http.ParseException;
import org.apache.http.client.ClientProtocolException;
import org.apache.http.client.entity.UrlEncodedFormEntity;
import org.apache.http.client.methods.CloseableHttpResponse;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.entity.StringEntity;
import org.apache.http.impl.client.CloseableHttpClient;
import org.apache.http.impl.client.HttpClients;
import org.apache.http.message.BasicNameValuePair;
import org.apache.http.util.EntityUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import com.alibaba.fastjson.JSONObject;
/**
* http访问方法实现
* @author 王俊南
* @date: 2018-11-22
*/
public class HttpRequestUtils {
private static Logger logger = LoggerFactory
.getLogger(HttpRequestUtils.class); // 日志记录
/**
* GET提交
*
* @return
*/
public static String doGet(String url) {
String strResult = "";
// 1. 创建一个默认的client实例
CloseableHttpClient client = HttpClients.createDefault();
try {
// 2. 创建一个httpget对象
HttpGet httpGet = new HttpGet(url);
System.out.println("executing GET request " + httpGet.getURI());
// 3. 执行GET请求并获取响应对象
CloseableHttpResponse resp = client.execute(httpGet);
try {
// 6. 打印响应长度和响应内容
if (resp.getStatusLine().getStatusCode() == HttpStatus.SC_OK) {
// 4. 获取响应体
HttpEntity entity = resp.getEntity();
System.out.println("Response content length = "
+ entity.getContentLength());
System.out.println("------");
strResult = EntityUtils.toString(resp.getEntity());
}
} finally {
//无论请求成功与否都要关闭resp
resp.close();
}
} catch (ClientProtocolException e) {
logger.error("get请求失败:", e);
// e.printStackTrace();
} catch (ParseException e) {
logger.error("get请求解析出错:", e);
// e.printStackTrace();
} catch (IOException e) {
logger.error("get请求IO出错:", e);
// e.printStackTrace();
} finally {
// 8. 最终要关闭连接,释放资源
try {
client.close();
} catch (Exception e) {
logger.error("get请求完毕关闭连接出错:", e);
// e.printStackTrace();
}
}
return strResult;
}
/**
* 普通POST提交
* @param url
* @param map
* @return
*/
public static String doPost(String url, Map<String, Object> map) {
String strResult = "";
// 1. 获取默认的client实例
CloseableHttpClient client = HttpClients.createDefault();
// 2. 创建httppost实例
HttpPost httpPost = new HttpPost(url);
// 3. 创建参数队列(键值对列表)
List<NameValuePair> paramPairs = new ArrayList<>();
Set<String> keySet = map.keySet();
for (String key : keySet) {
Object val = map.get(key);
paramPairs.add(new BasicNameValuePair(key, val.toString()));
}
UrlEncodedFormEntity entity;
try {
// 4. 将参数设置到entity对象中
entity = new UrlEncodedFormEntity(paramPairs, "UTF-8");
// 5. 将entity对象设置到httppost对象中
httpPost.setEntity(entity);
// 6. 发送请求并回去响应
CloseableHttpResponse resp = client.execute(httpPost);
try {
// 7. 获取响应entity
HttpEntity respEntity = resp.getEntity();
strResult = EntityUtils.toString(respEntity, "UTF-8");
} finally {
// 9. 关闭响应对象
resp.close();
}
} catch (ClientProtocolException e) {
e.printStackTrace();
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
} finally {
// 10. 关闭连接,释放资源
try {
client.close();
} catch (Exception e) {
e.printStackTrace();
}
}
return strResult;
}
/**
* json参数方式POST提交
* @param url
* @param params
* @return
*/
public static String doPost(String url, JSONObject params){
String strResult = "";
// 1. 获取默认的client实例
CloseableHttpClient client = HttpClients.createDefault();
// 2. 创建httppost实例
HttpPost httpPost = new HttpPost(url);
httpPost.addHeader("Content-Type", "application/json;charset=utf-8"); //添加请求头
try {
httpPost.setEntity(new StringEntity(params.toJSONString(),"utf-8"));
CloseableHttpResponse resp = client.execute(httpPost);
try {
// 7. 获取响应entity
HttpEntity respEntity = resp.getEntity();
strResult = EntityUtils.toString(respEntity, "UTF-8");
} finally {
resp.close();
}
} catch (ClientProtocolException e) {
e.printStackTrace();
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
} finally {
try {
client.close();
} catch (Exception e) {
e.printStackTrace();
}
}
return strResult;
}
}