Secara amnya pada platform Java, kami akan menggunakan Apache HttpClient sebagai klien Http untuk menghantar permintaan HTTP dan memproses respons. Sebagai contoh, anda boleh menyepadukan klien http dengan perkhidmatan pihak ketiga seperti perkhidmatan SSO, dan juga merangkak data di Internet. OKHttp adalah serupa dengan HttpClient Ia juga merupakan klien Http Ia menyediakan sokongan untuk HTTP/2 dan SPDY, dan menyediakan penyatuan sambungan, pemampatan GZIP dan fungsi caching respons HTTP
OkHttp kini merupakan perpustakaan rangkaian yang sangat popular , ia mempunyai ciri berikut:
1 Menyokong HTTP/2, membenarkan semua permintaan dengan alamat hos yang sama berkongsi sambungan soket yang sama
2
3. Pemampatan GZIP telus mengurangkan saiz data tindak balas4 Cache kandungan tindak balas untuk mengelakkan beberapa permintaan pendua sepenuhnyaPenggunaan asas OkHttpHantar permintaan Asynchronous http://square.github.io/okhttp/
<dependency>
<groupId>com.squareup.okhttp3</groupId>
<artifactId>okhttp</artifactId>
<version>3.10.0</version>
</dependency>
<dependency>
<groupId>com.alibaba</groupId>
<artifactId>fastjson</artifactId>
<version>1.2.60</version>
</dependency>package com.loginsimpl.utils;
import com.alibaba.fastjson.JSON;
import okhttp3.*;
import javax.net.ssl.SSLContext;
import javax.net.ssl.SSLSocketFactory;
import javax.net.ssl.TrustManager;
import javax.net.ssl.X509TrustManager;
import java.io.IOException;
import java.net.URLEncoder;
import java.security.SecureRandom;
import java.security.cert.X509Certificate;
import java.util.LinkedHashMap;
import java.util.Map;
import java.util.concurrent.Semaphore;
import java.util.concurrent.TimeUnit;
public class OkHttpUtils {
private static volatile OkHttpClient okHttpClient = null;
private static volatile Semaphore semaphore = null;
private Map<String, String> headerMap;
private Map<String, String> paramMap;
private String url;
private Request.Builder request;
/**
* 初始化okHttpClient，并且允许https访问
*/
private OkHttpUtils() {
if (okHttpClient == null) {
synchronized (OkHttpUtils.class) {
if (okHttpClient == null) {
TrustManager[] trustManagers = buildTrustManagers();
okHttpClient = new OkHttpClient.Builder()
.connectTimeout(15, TimeUnit.SECONDS)
.writeTimeout(20, TimeUnit.SECONDS)
.readTimeout(20, TimeUnit.SECONDS)
.sslSocketFactory(createSSLSocketFactory(trustManagers), (X509TrustManager) trustManagers[0])
.hostnameVerifier((hostName, session) -> true)
.retryOnConnectionFailure(true)
.build();
addHeader("User-Agent", "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_12_6) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/63.0.3239.132 Safari/537.36");
}
}
}
}
/**
* 用于异步请求时，控制访问线程数，返回结果
*
* @return
*/
private static Semaphore getSemaphoreInstance() {
//只能1个线程同时访问
synchronized (OkHttpUtils.class) {
if (semaphore == null) {
semaphore = new Semaphore(0);
}
}
return semaphore;
}
/**
* 创建OkHttpUtils
*
* @return
*/
public static OkHttpUtils builder() {
return new OkHttpUtils();
}
/**
* 添加url
*
* @param url
* @return
*/
public OkHttpUtils url(String url) {
this.url = url;
return this;
}
/**
* 添加参数
*
* @param key 参数名
* @param value 参数值
* @return
*/
public OkHttpUtils addParam(String key, String value) {
if (paramMap == null) {
paramMap = new LinkedHashMap<>(16);
}
paramMap.put(key, value);
return this;
}
/**
* 添加请求头
*
* @param key 参数名
* @param value 参数值
* @return
*/
public OkHttpUtils addHeader(String key, String value) {
if (headerMap == null) {
headerMap = new LinkedHashMap<>(16);
}
headerMap.put(key, value);
return this;
}
/**
* 初始化get方法
*
* @return
*/
public OkHttpUtils get() {
request = new Request.Builder().get();
StringBuilder urlBuilder = new StringBuilder(url);
if (paramMap != null) {
urlBuilder.append("?");
try {
for (Map.Entry<String, String> entry : paramMap.entrySet()) {
urlBuilder.append(URLEncoder.encode(entry.getKey(), "utf-8")).
append("=").
append(URLEncoder.encode(entry.getValue(), "utf-8")).
append("&");
}
} catch (Exception e) {
e.printStackTrace();
}
urlBuilder.deleteCharAt(urlBuilder.length() - 1);
}
request.url(urlBuilder.toString());
return this;
}
/**
* 初始化post方法
*
* @param isJsonPost true等于json的方式提交数据，类似postman里post方法的raw
* false等于普通的表单提交
* @return
*/
public OkHttpUtils post(boolean isJsonPost) {
RequestBody requestBody;
if (isJsonPost) {
String json = "";
if (paramMap != null) {
json = JSON.toJSONString(paramMap);
}
requestBody = RequestBody.create(MediaType.parse("application/json; charset=utf-8"), json);
} else {
FormBody.Builder formBody = new FormBody.Builder();
if (paramMap != null) {
paramMap.forEach(formBody::add);
}
requestBody = formBody.build();
}
request = new Request.Builder().post(requestBody).url(url);
return this;
}
/**
* 同步请求
*
* @return
*/
public String sync() {
setHeader(request);
try {
Response response = okHttpClient.newCall(request.build()).execute();
assert response.body() != null;
return response.body().string();
} catch (IOException e) {
e.printStackTrace();
return "请求失败：" + e.getMessage();
}
}
/**
* 异步请求，有返回值 (限流的,同一时间只允许一个访问,其他等待)
*/
public String async() {
StringBuilder buffer = new StringBuilder("");
setHeader(request);
okHttpClient.newCall(request.build()).enqueue(new Callback() {
@Override
public void onFailure(Call call, IOException e) {
buffer.append("请求出错：").append(e.getMessage());
}
@Override
public void onResponse(Call call, Response response) throws IOException {
assert response.body() != null;
buffer.append(response.body().string());
getSemaphoreInstance().release();
}
});
try {
getSemaphoreInstance().acquire();
} catch (InterruptedException e) {
e.printStackTrace();
}
return buffer.toString();
}
/**
* 异步请求，带有接口回调
*
* @param callBack
*/
public void async(ICallBack callBack) {
setHeader(request);
okHttpClient.newCall(request.build()).enqueue(new Callback() {
@Override
public void onFailure(Call call, IOException e) {
callBack.onFailure(call, e.getMessage());
}
@Override
public void onResponse(Call call, Response response) throws IOException {
assert response.body() != null;
callBack.onSuccessful(call, response.body().string());
}
});
}
/**
* 为request添加请求头
*
* @param request
*/
private void setHeader(Request.Builder request) {
if (headerMap != null) {
try {
for (Map.Entry<String, String> entry : headerMap.entrySet()) {
request.addHeader(entry.getKey(), entry.getValue());
}
} catch (Exception e) {
e.printStackTrace();
}
}
}
/**
* 生成安全套接字工厂，用于https请求的证书跳过
*
* @return
*/
private static SSLSocketFactory createSSLSocketFactory(TrustManager[] trustAllCerts) {
SSLSocketFactory ssfFactory = null;
try {
SSLContext sc = SSLContext.getInstance("SSL");
sc.init(null, trustAllCerts, new SecureRandom());
ssfFactory = sc.getSocketFactory();
} catch (Exception e) {
e.printStackTrace();
}
return ssfFactory;
}
private static TrustManager[] buildTrustManagers() {
return new TrustManager[]{
new X509TrustManager() {
@Override
public void checkClientTrusted(X509Certificate[] chain, String authType) {
}
@Override
public void checkServerTrusted(X509Certificate[] chain, String authType) {
}
@Override
public X509Certificate[] getAcceptedIssuers() {
return new X509Certificate[]{};
}
}
};
}
/**
* 自定义一个接口回调
*/
public interface ICallBack {
void onSuccessful(Call call, String data);
void onFailure(Call call, String errorMsg);
}
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