httpclients 和 okhttp 区别

HttpClient使用介绍
使用HttpClient发送请求主要分为以下几步骤：

创建 CloseableHttpClient对象或CloseableHttpAsyncClient对象，前者同步，后者为异步

创建Http请求对象

调用execute方法执行请求，如果是异步请求在执行之前需调用start方法

创建连接：

CloseableHttpClient httpClient = HttpClientBuilder.create().build();
该连接为同步连接

GET请求：

@Test
public void testGet() throws IOException {
String api = "/api/files/1";
String url = String.format("%s%s", BASE_URL, api);
HttpGet httpGet = new HttpGet(url);
CloseableHttpResponse response = httpClient.execute(httpGet);
System.out.println(EntityUtils.toString(response.getEntity()));
}
使用HttpGet表示该连接为GET请求，HttpClient调用execute方法发送GET请求

PUT请求：

@Test
public void testPut() throws IOException {
String api = "/api/user";
String url = String.format("%s%s", BASE_URL, api);
HttpPut httpPut = new HttpPut(url);
UserVO userVO = UserVO.builder().name("h2t").id(16L).build();
httpPut.setHeader("Content-Type", "application/json;charset=utf8");
httpPut.setEntity(new StringEntity(JSONObject.toJSONString(userVO), "UTF-8"));
CloseableHttpResponse response = httpClient.execute(httpPut);
System.out.println(EntityUtils.toString(response.getEntity()));
}
POST请求：

添加对象

@Test
public void testPost() throws IOException {
String api = "/api/user";
String url = String.format("%s%s", BASE_URL, api);
HttpPost httpPost = new HttpPost(url);
UserVO userVO = UserVO.builder().name("h2t2").build();
httpPost.setHeader("Content-Type", "application/json;charset=utf8");
httpPost.setEntity(new StringEntity(JSONObject.toJSONString(userVO), "UTF-8"));
CloseableHttpResponse response = httpClient.execute(httpPost);
System.out.println(EntityUtils.toString(response.getEntity()));
}
该请求是一个创建对象的请求，需要传入一个json字符串

上传文件

@Test
public void testUpload1() throws IOException {
String api = "/api/files/1";
String url = String.format("%s%s", BASE_URL, api);
HttpPost httpPost = new HttpPost(url);
File file = new File("C:/Users/hetiantian/Desktop/学习/docker_practice.pdf");
FileBody fileBody = new FileBody(file);
MultipartEntityBuilder builder = MultipartEntityBuilder.create();
builder.setMode(HttpMultipartMode.BROWSER_COMPATIBLE);
builder.addPart("file", fileBody); //addPart上传文件
HttpEntity entity = builder.build();
httpPost.setEntity(entity);
CloseableHttpResponse response = httpClient.execute(httpPost);
System.out.println(EntityUtils.toString(response.getEntity()));
}

通过addPart上传文件

DELETE请求：

@Test
public void testDelete() throws IOException {
String api = "/api/user/12";
String url = String.format("%s%s", BASE_URL, api);
HttpDelete httpDelete = new HttpDelete(url);
CloseableHttpResponse response = httpClient.execute(httpDelete);
System.out.println(EntityUtils.toString(response.getEntity()));
}
请求的取消：

@Test
public void testCancel() throws IOException {
String api = "/api/files/1";
String url = String.format("%s%s", BASE_URL, api);
HttpGet httpGet = new HttpGet(url);
httpGet.setConfig(requestConfig); //设置超时时间
//测试连接的取消

long begin = System.currentTimeMillis();
CloseableHttpResponse response = httpClient.execute(httpGet);
while (true) {
if (System.currentTimeMillis() - begin > 1000) {
httpGet.abort();
System.out.println("task canceled");
break;
}
}

System.out.println(EntityUtils.toString(response.getEntity()));
}

调用abort方法取消请求 执行结果：

task canceled
cost 8098 msc
Disconnected from the target VM, address: '127.0.0.1:60549', transport: 'socket'

java.net.SocketException: socket closed...【省略】

OkHttp使用

使用OkHttp发送请求主要分为以下几步骤：

创建OkHttpClient对象

创建Request对象

将Request 对象封装为Call

通过Call 来执行同步或异步请求，调用execute方法同步执行，调用enqueue方法异步执行

创建连接：

private OkHttpClient client = new OkHttpClient();
GET请求：

@Test
public void testGet() throws IOException {
String api = "/api/files/1";
String url = String.format("%s%s", BASE_URL, api);
Request request = new Request.Builder()
.url(url)
.get()
.build();
final Call call = client.newCall(request);
Response response = call.execute();
System.out.println(response.body().string());
}
PUT请求：

@Test
public void testPut() throws IOException {
String api = "/api/user";
String url = String.format("%s%s", BASE_URL, api);
//请求参数
UserVO userVO = UserVO.builder().name("h2t").id(11L).build();
RequestBody requestBody = RequestBody.create(MediaType.parse("application/json; charset=utf-8"),
JSONObject.toJSONString(userVO));
Request request = new Request.Builder()
.url(url)
.put(requestBody)
.build();
final Call call = client.newCall(request);
Response response = call.execute();
System.out.println(response.body().string());
}
POST请求：

添加对象

@Test
public void testPost() throws IOException {
String api = "/api/user";
String url = String.format("%s%s", BASE_URL, api);
//请求参数
JSONObject json = new JSONObject();
json.put("name", "hetiantian");
RequestBody requestBody = RequestBody.create(MediaType.parse("application/json; charset=utf-8"), String.valueOf(json));
Request request = new Request.Builder()
.url(url)
.post(requestBody) //post请求
.build();
final Call call = client.newCall(request);
Response response = call.execute();
System.out.println(response.body().string());
}

上传文件

@Test
public void testUpload() throws IOException {
String api = "/api/files/1";
String url = String.format("%s%s", BASE_URL, api);
RequestBody requestBody = new MultipartBody.Builder()
.setType(MultipartBody.FORM)
.addFormDataPart("file", "docker_practice.pdf",
RequestBody.create(MediaType.parse("multipart/form-data"),
new File("C:/Users/hetiantian/Desktop/学习/docker_practice.pdf")))
.build();
Request request = new Request.Builder()
.url(url)
.post(requestBody) //默认为GET请求，可以不写
.build();
final Call call = client.newCall(request);
Response response = call.execute();
System.out.println(response.body().string());
}

通过addFormDataPart方法模拟表单方式上传文件

DELETE请求：

@Test
public void testDelete() throws IOException {
String url = String.format("%s%s", BASE_URL, api);
//请求参数
Request request = new Request.Builder()
.url(url)
.delete()
.build();
final Call call = client.newCall(request);
Response response = call.execute();
System.out.println(response.body().string());
}
请求的取消：

@Test
public void testCancelSysnc() throws IOException {
String api = "/api/files/1";
String url = String.format("%s%s", BASE_URL, api);
Request request = new Request.Builder()
.url(url)
.get()
.build();
final Call call = client.newCall(request);
Response response = call.execute();
long start = System.currentTimeMillis();
//测试连接的取消
while (true) {
//1分钟获取不到结果就取消请求
if (System.currentTimeMillis() - start > 1000) {
call.cancel();
System.out.println("task canceled");
break;
}
}

System.out.println(response.body().string());
}
调用cancel方法进行取消 测试结果：

HttpClient超时设置：
在HttpClient4.3+版本以上，超时设置通过RequestConfig进行设置

private CloseableHttpClient httpClient = HttpClientBuilder.create().build();
private RequestConfig requestConfig = RequestConfig.custom()
.setSocketTimeout(60 * 1000)
.setConnectTimeout(60 * 1000).build();
String api = "/api/files/1";
String url = String.format("%s%s", BASE_URL, api);
HttpGet httpGet = new HttpGet(url);
httpGet.setConfig(requestConfig); //设置超时时间
超时时间是设置在请求类型HttpGet上，而不是HttpClient上

OkHttp超时设置：
直接在OkHttp上进行设置

private OkHttpClient client = new OkHttpClient.Builder()
.connectTimeout(60, TimeUnit.SECONDS)//设置连接超时时间
.readTimeout(60, TimeUnit.SECONDS)//设置读取超时时间
.build();
小结：
如果client是单例模式，HttpClient在设置超时方面来的更灵活，针对不同请求类型设置不同的超时时间，OkHttp一旦设置了超时时间，所有请求类型的超时时间也就确定

总结：

OkHttp和HttpClient在性能和使用上不分伯仲，根据实际业务选择即可。