一、简介
使用 appache 的 httpclient 来实现的
二、源码
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package com.ray.weixin.gz.util; import java.io.File; import java.io.FileOutputStream; import java.io.IOException; import java.io.InputStream; import org.apache.http.Consts; import org.apache.http.Header; import org.apache.http.HeaderElement; import org.apache.http.HttpEntity; import org.apache.http.HttpResponse; import org.apache.http.HttpStatus; import org.apache.http.NameValuePair; import org.apache.http.client.config.RequestConfig; 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.ContentType; import org.apache.http.entity.StringEntity; import org.apache.http.entity.mime.MultipartEntityBuilder; import org.apache.http.entity.mime.content.FileBody; import org.apache.http.impl.client.CloseableHttpClient; import org.apache.http.impl.client.HttpClients; import org.apache.http.protocol.BasicHttpContext; import org.apache.http.util.EntityUtils; import com.alibaba.fastjson.JSON; import com.alibaba.fastjson.JSONObject; /** * HTTP请求封装,建议直接使用sdk的API */ public class HttpHelper { /** * @desc :1.发起GET请求 * * @param url * @return JSONObject * @throws Exception */ public static JSONObject doGet(String url) throws Exception { //1.生成一个请求 HttpGet httpGet = new HttpGet(url); //2.配置请求的属性 RequestConfig requestConfig = RequestConfig.custom().setSocketTimeout(10000).setConnectTimeout(10000).build();//2000 httpGet.setConfig(requestConfig); //3.发起请求,获取响应信息 //3.1 创建httpClient CloseableHttpClient httpClient = HttpClients.createDefault(); CloseableHttpResponse response = null; try { //3.2 发起请求,获取响应信息 response = httpClient.execute(httpGet, new BasicHttpContext()); //如果返回结果的code不等于200,说明出错了 if (response.getStatusLine().getStatusCode() != 200) { System.out.println("request url failed, http code=" + response.getStatusLine().getStatusCode() + ", url=" + url); return null; } //4.解析请求结果 HttpEntity entity = response.getEntity(); //reponse返回的数据在entity中 if (entity != null) { String resultStr = EntityUtils.toString(entity, "utf-8"); //将数据转化为string格式 System.out.println("GET请求结果:"+resultStr); JSONObject result = JSON.parseObject(resultStr); //将String转换为 JSONObject if(result.getInteger("errcode")==null) { return result; }else if (0 == result.getInteger("errcode")) { return result; }else { System.out.println("request url=" + url + ",return value="); System.out.println(resultStr); int errCode = result.getInteger("errcode"); String errMsg = result.getString("errmsg"); throw new Exception("error code:"+errCode+", error message:"+errMsg); } } } catch (IOException e) { System.out.println("request url=" + url + ", exception, msg=" + e.getMessage()); e.printStackTrace(); } finally { if (response != null) try { response.close(); //释放资源 } catch (IOException e) { e.printStackTrace(); } } return null; } /** 2.发起POST请求 * @desc : * * @param url 请求url * @param data 请求参数(json) * @return * @throws Exception JSONObject */ public static JSONObject doPost(String url, Object data) throws Exception { //1.生成一个请求 HttpPost httpPost = new HttpPost(url); //2.配置请求属性 //2.1 设置请求超时时间 RequestConfig requestConfig = RequestConfig.custom().setSocketTimeout(100000).setConnectTimeout(100000).build(); httpPost.setConfig(requestConfig); //2.2 设置数据传输格式-json httpPost.addHeader("Content-Type", "application/json"); //2.3 设置请求实体,封装了请求参数 StringEntity requestEntity = new StringEntity(JSON.toJSONString(data), "utf-8"); httpPost.setEntity(requestEntity); //3.发起请求,获取响应信息 //3.1 创建httpClient CloseableHttpClient httpClient = HttpClients.createDefault(); CloseableHttpResponse response = null; try { //3.3 发起请求,获取响应 response = httpClient.execute(httpPost, new BasicHttpContext()); if (response.getStatusLine().getStatusCode() != 200) { System.out.println("request url failed, http code=" + response.getStatusLine().getStatusCode() + ", url=" + url); return null; } //获取响应内容 HttpEntity entity = response.getEntity(); if (entity != null) { String resultStr = EntityUtils.toString(entity, "utf-8"); System.out.println("POST请求结果:"+resultStr); //解析响应内容 JSONObject result = JSON.parseObject(resultStr); if(result.getInteger("errcode")==null) { return result; }else if (0 == result.getInteger("errcode")) { return result; }else { System.out.println("request url=" + url + ",return value="); System.out.println(resultStr); int errCode = result.getInteger("errcode"); String errMsg = result.getString("errmsg"); throw new Exception("error code:"+errCode+", error message:"+errMsg); } } } catch (IOException e) { System.out.println("request url=" + url + ", exception, msg=" + e.getMessage()); e.printStackTrace(); } finally { if (response != null) try { response.close(); //释放资源 } catch (IOException e) { e.printStackTrace(); } } return null; } /** * @desc : 3.上传文件 * * @param url 请求url * @param file 上传的文件 * @return * @throws Exception JSONObject */ public static JSONObject uploadMedia(String url, File file) throws Exception { HttpPost httpPost = new HttpPost(url); CloseableHttpResponse response = null; CloseableHttpClient httpClient = HttpClients.createDefault(); RequestConfig requestConfig = RequestConfig.custom().setSocketTimeout(5000).setConnectTimeout(5000).build(); httpPost.setConfig(requestConfig); //2.3 设置请求实体,封装了请求参数 HttpEntity requestEntity = MultipartEntityBuilder.create().addPart("media", new FileBody(file, ContentType.create("multipart/form-data", Consts.UTF_8), file.getName())).build(); //FileEntity requestEntity = new FileEntity(file,ContentType.MULTIPART_FORM_DATA); httpPost.setEntity(requestEntity); try { response = httpClient.execute(httpPost, new BasicHttpContext()); if (response.getStatusLine().getStatusCode() != 200) { System.out.println("request url failed, http code=" + response.getStatusLine().getStatusCode() + ", url=" + url); return null; } HttpEntity entity = response.getEntity(); if (entity != null) { String resultStr = EntityUtils.toString(entity, "utf-8"); JSONObject result = JSON.parseObject(resultStr); //上传临时素材失败 if (result.getInteger("errcode") != null && 0 != result.getInteger("errcode") ) { System.out.println("request url=" + url + ",return value="); System.out.println(resultStr); int errCode = result.getInteger("errcode"); String errMsg = result.getString("errmsg"); throw new Exception("error code:"+errCode+", error message:"+errMsg); //上传临时素材成功 }else { //result.remove("errcode"); //result.remove("errmsg"); return result; } } } catch (IOException e) { System.out.println("request url=" + url + ", exception, msg=" + e.getMessage()); e.printStackTrace(); } finally { if (response != null) try { response.close(); //释放资源 } catch (IOException e) { e.printStackTrace(); } } return null; } /** * @desc : 上传PDF * 见微信电子发票章节 * 9. 向用户提供发票或其它消费凭证PDF * * @param url * @param file * @return * @throws Exception * JSONObject */ public static JSONObject uploadPDF(String url, File file) throws Exception { HttpPost httpPost = new HttpPost(url); CloseableHttpResponse response = null; CloseableHttpClient httpClient = HttpClients.createDefault(); RequestConfig requestConfig = RequestConfig.custom().setSocketTimeout(5000).setConnectTimeout(5000).build(); httpPost.setConfig(requestConfig); //2.3 设置请求实体,封装了请求参数 HttpEntity requestEntity = MultipartEntityBuilder.create().addPart("media", new FileBody(file, ContentType.create("multipart/form-data", Consts.UTF_8), file.getName())).build(); httpPost.setEntity(requestEntity); try { response = httpClient.execute(httpPost, new BasicHttpContext()); if (response.getStatusLine().getStatusCode() != 200) { System.out.println("request url failed, http code=" + response.getStatusLine().getStatusCode() + ", url=" + url); return null; } HttpEntity entity = response.getEntity(); if (entity != null) { String resultStr = EntityUtils.toString(entity, "utf-8"); JSONObject result = JSON.parseObject(resultStr); //上传临时素材成功 if (result.getString("errcode")== null) { // 成功 //result.remove("errcode"); //result.remove("errmsg"); return result; } else { System.out.println("request url=" + url + ",return value="); System.out.println(resultStr); int errCode = result.getInteger("errcode"); String errMsg = result.getString("errmsg"); throw new Exception("error code:"+errCode+", error message:"+errMsg); } } } catch (IOException e) { System.out.println("request url=" + url + ", exception, msg=" + e.getMessage()); e.printStackTrace(); } finally { if (response != null) try { response.close(); //释放资源 } catch (IOException e) { e.printStackTrace(); } } return null; } /** * @desc : 4.下载文件 -get * * @param url 请求url * @param fileDir 下载路径 * @return * @throws Exception File */ public static File downloadMedia(String url, String fileDir) throws Exception { //1.生成一个请求 HttpGet httpGet = new HttpGet(url); //2.配置请求属性 RequestConfig requestConfig = RequestConfig.custom().setSocketTimeout(100000).setConnectTimeout(100000).build(); httpGet.setConfig(requestConfig); //3.发起请求,获取响应信息 //3.1 创建httpClient CloseableHttpClient httpClient = HttpClients.createDefault(); CloseableHttpResponse response = null; //4.设置本地保存的文件 //File file = new File(fileDir); File file = null; try { //5. 发起请求,获取响应信息 response = httpClient.execute(httpGet, new BasicHttpContext()); System.out.println("HttpStatus.SC_OK:"+HttpStatus.SC_OK); System.out.println("response.getStatusLine().getStatusCode():"+response.getStatusLine().getStatusCode()); System.out.println("http-header:"+JSON.toJSONString( response.getAllHeaders() )); System.out.println("http-filename:"+getFileName(response) ); //请求成功 if(HttpStatus.SC_OK==response.getStatusLine().getStatusCode()){ //6.取得请求内容 HttpEntity entity = response.getEntity(); if (entity != null) { //这里可以得到文件的类型 如image/jpg /zip /tiff 等等 但是发现并不是十分有效,有时明明后缀是.rar但是取到的是null,这点特别说明 System.out.println(entity.getContentType()); //可以判断是否是文件数据流 System.out.println(entity.isStreaming()); //6.1 输出流 //6.1.1获取文件名,拼接文件路径 String fileName=getFileName(response); fileDir=fileDir+fileName; file = new File(fileDir); //6.1.2根据文件路径获取输出流 FileOutputStream output = new FileOutputStream(file); //6.2 输入流:从钉钉服务器返回的文件流,得到网络资源并写入文件 InputStream input = entity.getContent(); //6.3 将数据写入文件:将输入流中的数据写入到输出流 byte b[] = new byte[1024]; int j = 0; while( (j = input.read(b))!=-1){ output.write(b,0,j); } output.flush(); output.close(); } if (entity != null) { entity.consumeContent(); } } } catch (IOException e) { System.out.println("request url=" + url + ", exception, msg=" + e.getMessage()); e.printStackTrace(); } finally { if (response != null) try { response.close(); //释放资源 } catch (IOException e) { e.printStackTrace(); } } return file; } /** * @desc : 5.下载文件 - post * * @param url 请求url * @param data post请求参数 * @param fileDir 文件下载路径 * @return * @throws Exception File */ public static File downloadMedia(String url, Object data, String fileDir) throws Exception { //1.生成一个请求 HttpPost httpPost = new HttpPost(url); //2.配置请求属性 //2.1 设置请求超时时间 RequestConfig requestConfig = RequestConfig.custom().setSocketTimeout(100000).setConnectTimeout(100000).build(); httpPost.setConfig(requestConfig); //2.2 设置数据传输格式-json httpPost.addHeader("Content-Type", "application/json"); //2.3 设置请求参数 StringEntity requestEntity = new StringEntity(JSON.toJSONString(data), "utf-8"); httpPost.setEntity(requestEntity); //3.发起请求,获取响应信息 //3.1 创建httpClient CloseableHttpClient httpClient = HttpClients.createDefault(); CloseableHttpResponse response = null; //4.设置本地保存的文件 //File file = new File(fileDir); File file = null; try { //5. 发起请求,获取响应信息 response = httpClient.execute(httpPost, new BasicHttpContext()); System.out.println("HttpStatus.SC_OK:"+HttpStatus.SC_OK); System.out.println("response.getStatusLine().getStatusCode():"+response.getStatusLine().getStatusCode()); System.out.println("http-header:"+JSON.toJSONString( response.getAllHeaders() )); System.out.println("http-filename:"+getFileName(response) ); //请求成功 if(HttpStatus.SC_OK==response.getStatusLine().getStatusCode()){ //6.取得请求内容 HttpEntity entity = response.getEntity(); if (entity != null) { //这里可以得到文件的类型 如image/jpg /zip /tiff 等等 但是发现并不是十分有效,有时明明后缀是.rar但是取到的是null,这点特别说明 System.out.println(entity.getContentType()); //可以判断是否是文件数据流 System.out.println(entity.isStreaming()); //6.1 输出流 //6.1.1获取文件名,拼接文件路径 String fileName=getFileName(response); fileDir=fileDir+fileName; file = new File(fileDir); //6.1.2根据文件路径获取输出流 FileOutputStream output = new FileOutputStream(file); //6.2 输入流:从钉钉服务器返回的文件流,得到网络资源并写入文件 InputStream input = entity.getContent(); //6.3 将数据写入文件:将输入流中的数据写入到输出流 byte b[] = new byte[1024]; int j = 0; while( (j = input.read(b))!=-1){ output.write(b,0,j); } output.flush(); output.close(); } if (entity != null) { entity.consumeContent(); } } } catch (IOException e) { System.out.println("request url=" + url + ", exception, msg=" + e.getMessage()); e.printStackTrace(); } finally { if (response != null) try { response.close(); //释放资源 } catch (IOException e) { e.printStackTrace(); } } return file; } /** 5. 获取response header中Content-Disposition中的filename值 * @desc : * * @param response 响应 * @return String */ public static String getFileName(HttpResponse response) { Header contentHeader = response.getFirstHeader("Content-Disposition"); String filename = null; if (contentHeader != null) { HeaderElement[] values = contentHeader.getElements(); if (values.length == 1) { NameValuePair param = values[0].getParameterByName("filename"); if (param != null) { try { //filename = new String(param.getValue().toString().getBytes(), "utf-8"); //filename=URLDecoder.decode(param.getValue(),"utf-8"); filename = param.getValue(); } catch (Exception e) { e.printStackTrace(); } } } } return filename; } }