一，基础的的应用
1.1，get的无参请求
@Test
public void doGet() throws Exception {
//创建一个httpclient对象
CloseableHttpClient httpClient = HttpClients.createDefault();
//创建一个GET对象
HttpGet get = new HttpGet("http://www.sogou.com");
//执行请求
CloseableHttpResponse response = httpClient.execute(get);
//取响应的结果
int statusCode = response.getStatusLine().getStatusCode();
System.out.println(statusCode);
HttpEntity entity = response.getEntity();
String string = EntityUtils.toString(entity, "utf-8");
System.out.println(string);
//关闭httpclient
response.close();
httpClient.close();
}
1.2，get的带参请求
public void doGetWithParam() throws Exception{
//创建一个httpclient对象
CloseableHttpClient httpClient = HttpClients.createDefault();
//创建一个uri对象
URIBuilder uriBuilder = new URIBuilder("http://www.sogou.com/web");
uriBuilder.addParameter("query", "花千骨");
HttpGet get = new HttpGet(uriBuilder.build());
//执行请求
CloseableHttpResponse response = httpClient.execute(get);
//取响应的结果
int statusCode = response.getStatusLine().getStatusCode();
System.out.println(statusCode);
HttpEntity entity = response.getEntity();
String string = EntityUtils.toString(entity, "utf-8");
System.out.println(string);
//关闭httpclient
response.close();
httpClient.close();
}
1.3，post的无参请求
public void doPost() throws Exception {
CloseableHttpClient httpClient = HttpClients.createDefault();
//创建一个post对象
HttpPost post = new HttpPost("http://localhost:8082/httpclient/post.action");
//执行post请求
CloseableHttpResponse response = httpClient.execute(post);
String string = EntityUtils.toString(response.getEntity());
System.out.println(string);
response.close();
httpClient.close();
}
1.4.1，post的带参请求
public void doPostWithParam() throws Exception{
CloseableHttpClient httpClient = HttpClients.createDefault();
//创建一个post对象
HttpPost post = new HttpPost("http://localhost:8082/httpclient/post.action");
//创建一个Entity。模拟一个表单
List<NameValuePair> kvList = new ArrayList<>();
kvList.add(new BasicNameValuePair("username", "张三"));
kvList.add(new BasicNameValuePair("password", "123"));
//包装成一个Entity对象
StringEntity entity = new UrlEncodedFormEntity(kvList, "utf-8");
//设置请求的内容
post.setEntity(entity);
//执行post请求
CloseableHttpResponse response = httpClient.execute(post);
String string = EntityUtils.toString(response.getEntity());
System.out.println(string);
response.close();
httpClient.close();
}
1.4.2,post的请求服务器8082的写法
@RequestMapping(value="/httpclient/post", method=RequestMethod.POST,
produces=MediaType.TEXT_PLAIN_VALUE+";charset=utf-8")
@ResponseBody
public String testPost(String username, String password) {
String result = "username:" + username + "\tpassword:" + password;
System.out.println(result);
return "username:" + username + ",password:" + password;
}
二，httpclient的工具封装
2.1，get的带参和无参的工具类
public static String doGet(String url, Map<String, String> param) {
// 创建Httpclient对象
CloseableHttpClient httpclient = HttpClients.createDefault();
String resultString = "";
CloseableHttpResponse response = null;
try {
// 创建uri
URIBuilder builder = new URIBuilder(url);
if (param != null) {
for (String key : param.keySet()) {
builder.addParameter(key, param.get(key));
}
}
URI uri = builder.build();
// 创建http GET请求
HttpGet httpGet = new HttpGet(uri);
// 执行请求
response = httpclient.execute(httpGet);
// 判断返回状态是否为200
if (response.getStatusLine().getStatusCode() == 200) {
resultString = EntityUtils.toString(response.getEntity(), "UTF-8");
}
} catch (Exception e) {
e.printStackTrace();
} finally {
try {
if (response != null) {
response.close();
}
httpclient.close();
} catch (IOException e) {
e.printStackTrace();
}
}
return resultString;
}
public static String doGet(String url) {
return doGet(url, null);
}
2.2，post的带参和无参的工具类 （参数的数据类型是map）
public static String doPost(String url, Map<String, String> param) {
// 创建Httpclient对象
CloseableHttpClient httpClient = HttpClients.createDefault();
CloseableHttpResponse response = null;
String resultString = "";
try {
// 创建Http Post请求
HttpPost httpPost = new HttpPost(url);
// 创建参数列表
if (param != null) {
List<NameValuePair> paramList = new ArrayList<>();
for (String key : param.keySet()) {
paramList.add(new BasicNameValuePair(key, param.get(key)));
}
// 模拟表单
UrlEncodedFormEntity entity = new UrlEncodedFormEntity(paramList);
httpPost.setEntity(entity);
}
// 执行http请求
response = httpClient.execute(httpPost);
resultString = EntityUtils.toString(response.getEntity(), "utf-8");
} catch (Exception e) {
e.printStackTrace();
} finally {
try {
response.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
return resultString;
}
public static String doPost(String url) {
return doPost(url, null);
}
2.3，post的带参的请求（参数类型是json格式的数据）
public static String doPostJson(String url, String json) {
// 创建Httpclient对象
CloseableHttpClient httpClient = HttpClients.createDefault();
CloseableHttpResponse response = null;
String resultString = "";
try {
// 创建Http Post请求
HttpPost httpPost = new HttpPost(url);
// 创建请求内容
StringEntity entity = new StringEntity(json, ContentType.APPLICATION_JSON);
httpPost.setEntity(entity);
// 执行http请求
response = httpClient.execute(httpPost);
resultString = EntityUtils.toString(response.getEntity(), "utf-8");
} catch (Exception e) {
e.printStackTrace();
} finally {
try {
response.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
return resultString;
}
三，项目中的案例解析 （调用其它公司的图像识别为例）
3.1，调用的服务层的方法（第一个参数不一样，说明识别的证件不一样）
private OcrServer ocrServer = null;
@Override
public Map<String, Object> idCardRecognize(MultipartFile imageFile) {
return ocrServer.pictureRecognition("IdCard", imageFile);
}
@Override
public Map<String, Object> bankCardRecognize(MultipartFile imageFile) {
return ocrServer.pictureRecognition("BankCard", imageFile);
}
@Override
public Map<String, Object> veCardRecognize(MultipartFile imageFile) {
return ocrServer.pictureRecognition("VeCard", imageFile);
}
@Override
public Map<String, Object> driverCardRecognize(MultipartFile imageFile) {
return ocrServer.pictureRecognition("DriverCard", imageFile);
}
@Override
public Map<String, Object> businessLicenseRecognize(MultipartFile imageFile) {
return ocrServer.pictureRecognition("BusinessLicense", imageFile);
}
@Override
public Map<String, Object> ocrRecognize(String recotype,
MultipartFile imageFile) {
return ocrServer.pictureRecognition(recotype, imageFile);
}
public void setOcrServer(OcrServer ocrServer) {
this.ocrServer = ocrServer;
}
3.2，参数的封装，url的确定
public Map<String, Object> pictureRecognition(String recotype, MultipartFile imageFile) {
long begin = System.currentTimeMillis();
String result = null;
// 文件输入流
FileInputStream fs = null;
try {
String configValue = cpConfigService.getValueByConfigKey("ocr_server_config", "{'uri':'http://cloud.exocr.com/recognize','username':'test','password':'test'}");
Map<String, String> configMap = JsonUtils.json2Map2(configValue);
String postUrl = configMap.get("uri"); // 服务地址
Map<String, String> postParam = new HashMap<String, String>(10);
postParam.put("username", configMap.get("username")); // 用户名， 公有云测试可使用’test’
postParam.put("password", configMap.get("password")); // 密码，公有云测试可使用 ’test’
postParam.put("recotype", recotype); // BankCard
postParam.put("encoding", "utf-8"); // 返回结果的文字编码方式，取值包括：utf-8， 默认值 gb2312
postParam.put("head_portrait", "0"); // 是否返回头像（base64格式），只对身份证识别有效，取值范围：0，默认，不返回头像 1，则返回身份证的头像照片
postParam.put("crop_image", "0"); // 是否返回切边（base64格式），取值：0， 默认，不返回切边图 1， 返回切边图
postParam.put("b64", "1"); // 输入图片是否为base64格式，取值：0， 默认，二进制格式 1， base64格式
// base64编码图像
String base64 = new String(Base64.encodeBase64(imageFile.getBytes()));
postParam.put("image", base64); // 待识别的图像，可以是二进制也可以是base64格式
result = HttpUtil.postUrlAsString(postUrl, postParam, null, "utf-8");
logger.info("OCR识别结果{}", result);
} catch (Exception e) {
logger.error("OCR识别异常：", e);
StringBuilder sb = new StringBuilder();
sb.append("{'Error':'99','Details':'OCR识别异常:");
sb.append(e.getMessage()).append("'}");
result = sb.toString();
} finally {
if (null != fs) {
try {
fs.close();
} catch (IOException e) {
logger.error("File input stream close exception:", e);
}
}
}
// 记录接口调用耗时
logger.info("OCR服务调用耗时{},识别类型{}", System.currentTimeMillis() - begin, recotype);
try {
return JsonUtils.json2Map(result);
} catch (Exception e) {
logger.error("json to map exception:", e);
}
return null;
}
在这里假如没有特殊的请求的话完全可以 result = HttpUtil.postUrlAsString(postUrl, postParam, null, "utf-8")调用工具类的方法了返回的结果就是了。
public static String postUrlAsString(String url,
Map<String, String> params, Map<String, String> reqHeader,
String encode) throws Exception {
// 开始时间
long t1 = System.currentTimeMillis();
// 获得HttpPost对象
HttpPost httpPost = getHttpPost(url, params, encode);
// 发送请求
String result = executeHttpRequest(httpPost, reqHeader, encode);
// 结束时间
long t2 = System.currentTimeMillis();
// 调试信息
logger.debug("url:" + url);
logger.debug("params:" + params.toString());
logger.debug("reqHeader:" + reqHeader);
logger.debug("encode:" + encode);
logger.debug("result:" + result);
logger.debug("consume time:" + ((t2 - t1)));
// 返回结果
return result;
}
3.3，httppost对象的获取
private static HttpPost getHttpPost(String url, Map<String, String> params,
String encode) throws UnsupportedEncodingException {
HttpPost httpPost = new HttpPost(url);
if (params != null) {
List<NameValuePair> form = new ArrayList<NameValuePair>();
for (String name : params.keySet()) {
form.add(new BasicNameValuePair(name, params.get(name)));
}
UrlEncodedFormEntity entity = new UrlEncodedFormEntity(form,
encode);
httpPost.setEntity(entity);
}
return httpPost;
}
3.4，把获取到的参数传递给httppost对象
private static String executeHttpRequest(HttpUriRequest request,
Map<String, String> reqHeader, String encode) throws Exception {
HttpClient client = null;
String result = null;
try {
// 创建HttpClient对象
client = new DefaultHttpClient();
// 设置连接超时时间
client.getParams().setParameter(
CoreConnectionPNames.CONNECTION_TIMEOUT, 60);
// 设置Socket超时时间
client.getParams().setParameter(CoreConnectionPNames.SO_TIMEOUT,
36600);
// 设置请求头信息
if (reqHeader != null) {
for (String name : reqHeader.keySet()) {
request.addHeader(name, reqHeader.get(name));
}
}
// 获得返回结果
HttpResponse response = client.execute(request);
// 如果成功
if (response.getStatusLine().getStatusCode() == HttpStatus.SC_OK) {
encode = StringUtils.isNotEmpty(encode) ? encode : DEFAULT_ENCODE;
result = EntityUtils.toString(response.getEntity(), encode);
} else {
StringBuffer errorMsg = new StringBuffer();
errorMsg.append("httpStatus:");
errorMsg.append(response.getStatusLine().getStatusCode());
errorMsg.append(response.getStatusLine().getReasonPhrase());
errorMsg.append(", Header: ");
Header[] headers = response.getAllHeaders();
for (Header header : headers) {
errorMsg.append(header.getName());
errorMsg.append(":");
errorMsg.append(header.getValue());
}
logger.error("HttpResonse Error:" + errorMsg);
result = "{'Error':'98','Details':'" + errorMsg.toString() + "'}";
}
} catch (Exception e) {
logger.error("http连接异常", e);
throw new Exception("http连接异常");
} finally {
try {
client.getConnectionManager().shutdown();
} catch (Exception e) {
logger.error("finally HttpClient shutdown error", e);
}
}
return result;
}