Java OkHttp3工具類

okhttp3現在基本都在用的一個底層網絡框架。這篇博客主要的目的就是將OKHttp3這個框架在開發中能用到的地方都記錄下來，也當一個工具文檔爲日後使用時查找方便。

vOkHttpUtils

import com.google.gson.Gson;
import lombok.extern.slf4j.Slf4j;
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;

/**
 * @Author
 * @Date 2024/3
 * @Des
 */
@Slf4j
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，並且允許https訪問
     */
    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");
                }
            }
        }
    }

    /**
     * 用於異步請求時，控制訪問線程數，返回結果
     *
     * @return
     */
    private static Semaphore getSemaphoreInstance() {
        //只能1個線程同時訪問
        synchronized (OkHttpUtils.class) {
            if (semaphore == null) {
                semaphore = new Semaphore(0);
            }
        }
        return semaphore;
    }

    /**
     * 創建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;
    }

    /**
     * 添加參數
     *
     * @param key   參數名
     * @param value 參數值
     * @return
     */
    public OkHttpUtils addParam(String key, String value) {
        if (paramMap == null) {
            paramMap = new LinkedHashMap<>(16);
        }
        paramMap.put(key, value);
        return this;
    }

    /**
     * 添加請求頭
     *
     * @param key   參數名
     * @param value 參數值
     * @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等於json的方式提交數據，類似postman裏post方法的raw
     *                   false等於普通的表單提交
     * @return
     */
    public OkHttpUtils post(boolean isJsonPost) {
        RequestBody requestBody;
        if (isJsonPost) {
            String json = "";
            if (paramMap != null) {
                json = GsonUtils.toJSONString(paramMap);
                // 如果沒有GsonUtils工具類就用下面這行代碼
                // json = new Gson().toJson(value)
            }
            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;
    }

    /**
     * 同步請求
     *
     * @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 "請求失敗：" + e.getMessage();
        }
    }

    /**
     * 異步請求，有返回值
     */
    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("請求出錯：").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();
    }

    /**
     * 異步請求，帶有接口回調
     *
     * @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());
            }
        });
    }

    /**
     * 爲request添加請求頭
     *
     * @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();
            }
        }
    }


    /**
     * 生成安全套接字工廠，用於https請求的證書跳過
     *
     * @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[]{};
                    }
                }
        };
    }

    /**
     * 自定義一個接口回調
     */
    public interface ICallBack {

        void onSuccessful(Call call, String data);

        void onFailure(Call call, String errorMsg);

    }
}

v使用示例

public static void main(String[] args) {
    // get請求，方法順序按照這種方式，切記選擇post/get一定要放在倒數第二，同步或者異步倒數第一，纔會正確執行
    OkHttpUtils.builder().url("請求地址，http/https都可以")
            // 有參數的話添加參數，可多個
            .addParam("參數名", "參數值")
            .addParam("參數名", "參數值")
            // 也可以添加多個
            .addHeader("Content-Type", "application/json; charset=utf-8")
            .get()
            // 可選擇是同步請求還是異步請求
            //.async();
            .sync();

    // post請求，分爲兩種，一種是普通表單提交，一種是json提交
    OkHttpUtils.builder().url("請求地址，http/https都可以")
            // 有參數的話添加參數，可多個
            .addParam("參數名", "參數值")
            .addParam("參數名", "參數值")
            // 也可以添加多個
            .addHeader("Content-Type", "application/json; charset=utf-8")
            // 如果是true的話，會類似於postman中post提交方式的raw，用json的方式提交，不是表單
            // 如果是false的話傳統的表單提交
            .post(true)
            .sync();
    
    // 選擇異步有兩個方法，一個是帶回調接口，一個是直接返回結果
    OkHttpUtils.builder().url("")
            .post(false)
            .async();

    OkHttpUtils.builder().url("").post(false).async(new OkHttpUtils.ICallBack() {
        @Override
        public void onSuccessful(Call call, String data) {
            // 請求成功後的處理
        }

        @Override
        public void onFailure(Call call, String errorMsg) {
            // 請求失敗後的處理
        }
    });
}

v源碼地址

https://github.com/toutouge/javademosecond/tree/master/hellolearn