手动封装了一个 OkHttp3 工具类，用着贼舒服

矫情吗；* 2024-03-22 08:58 53阅读 0赞

在实际的系统开发过程中，我们通常会基于项目环境，封装一个公共的网络请求工具库，以便开发接口请求相关的需求时，能更加方便的使用。

以服务端编程为例，以下是小编封装工具类的实践过程。

废话不多说，直接上代码：

<dependency>
        <groupId>com.squareup.okhttp3</groupId>
        <artifactId>okhttp</artifactId>
        <version>3.14.9</version>
    </dependency>

import okhttp3.*;
    
    import java.io.IOException;
    import java.util.Map;
    import java.util.concurrent.TimeUnit;
    
    public class OkHttpUtils {
    
        // 创建OkHttpClient对象
        private static final OkHttpClient client = new OkHttpClient.Builder()
                .connectTimeout(30, TimeUnit.SECONDS) // 连接超时时间
                .readTimeout(30, TimeUnit.SECONDS) // 读取超时时间
                .writeTimeout(30, TimeUnit.SECONDS) // 写入超时时间
                .build();
    
        /**
         * GET请求
         * @param url 请求URL
         * @return 响应体字符串
         * @throws IOException 请求或响应过程中发生的错误
         */
        public static String get(String url) throws IOException {
            Request request = new Request.Builder()
                    .url(url)
                    .build();
            Response response = client.newCall(request).execute();
            if (response.isSuccessful()) {
                return response.body().string();
            } else {
                throw new IOException("Unexpected code " + response);
            }
        }
    
        /**
         * POST请求
         * @param url 请求URL
         * @param requestBody 请求体
         * @param headers 请求头
         * @return 响应体字符串
         * @throws IOException 请求或响应过程中发生的错误
         */
        public static String post(String url, RequestBody requestBody, Map<String, String> headers) throws IOException {
            Request.Builder builder = new Request.Builder()
                    .url(url)
                    .post(requestBody);
            if (headers != null && headers.size() > 0) {
                for (Map.Entry<String, String> entry : headers.entrySet()) {
                    builder.addHeader(entry.getKey(), entry.getValue());
                }
            }
            Request request = builder.build();
            Response response = client.newCall(request).execute();
            if (response.isSuccessful()) {
                return response.body().string();
            } else {
                throw new IOException("Unexpected code " + response);
            }
        }
    
        /**
         * 构造JSON请求体
         * @param jsonStr JSON字符串
         * @return JSON请求体
         */
        public static RequestBody buildJsonRequestBody(String jsonStr) {
            return RequestBody.create(MediaType.parse("application/json"), jsonStr);
        }
    
        /**
         * 构造表单请求体
         * @param formParams 表单参数
         * @return 表单请求体
         */
        public static RequestBody buildFormRequestBody(Map<String, String> formParams) {
            FormBody.Builder builder = new FormBody.Builder();
            if (formParams != null && formParams.size() > 0) {
                for (Map.Entry<String, String> entry : formParams.entrySet()) {
                    builder.add(entry.getKey(), entry.getValue());
                }
            }
            return builder.build();
        }
    
        /**
         * 构造Multipart请求体
         * @param multipartParams Multipart参数
         * @return Multipart请求体
         */
        public static RequestBody buildMultipartRequestBody(Map<String, Object> multipartParams) {
            MultipartBody.Builder builder = new MultipartBody.Builder()
                    .setType(MultipartBody.FORM);
            if (multipartParams != null && multipartParams.size() > 0) {
                for (Map.Entry<String, Object>         entry : multipartParams.entrySet()) {
                String key = entry.getKey();
                Object value = entry.getValue();
                if (value instanceof String) {
                    builder.addFormDataPart(key, (String) value);
                } else if (value instanceof byte[]) {
                    builder.addFormDataPart(key, null,
                            RequestBody.create(MediaType.parse("application/octet-stream"), (byte[]) value));
                } else if (value instanceof RequestBody) {
                    builder.addFormDataPart(key, null, (RequestBody) value);
                }
            }
        }
        return builder.build();
    }
    
    /**
     * 构造Multipart请求体，支持上传文件
     * @param multipartParams Multipart参数
     * @return Multipart请求体
     */
    public static RequestBody buildMultipartRequestBodyWithFiles(Map<String, Object> multipartParams) {
        MultipartBody.Builder builder = new MultipartBody.Builder()
                .setType(MultipartBody.FORM);
        if (multipartParams != null && multipartParams.size() > 0) {
            for (Map.Entry<String, Object> entry : multipartParams.entrySet()) {
                String key = entry.getKey();
                Object value = entry.getValue();
                if (value instanceof String) {
                    builder.addFormDataPart(key, (String) value);
                } else if (value instanceof byte[]) {
                    builder.addFormDataPart(key, null,
                            RequestBody.create(MediaType.parse("application/octet-stream"), (byte[]) value));
                } else if (value instanceof RequestBody) {
                    builder.addFormDataPart(key, null, (RequestBody) value);
                } else if (value instanceof UploadFile) { // 支持上传文件
                    UploadFile file = (UploadFile) value;
                    builder.addFormDataPart(key, file.getName(),
                            RequestBody.create(MediaType.parse(file.getMimeType()), file.getFile()));
                }
            }
        }
        return builder.build();
    }
    
    /**
     * 上传文件
     * @param url 请求URL
     * @param file 上传的文件
     * @param headers 请求头
     * @return 响应体字符串
     * @throws IOException 请求或响应过程中发生的错误
     */
    public static String uploadFile(String url, UploadFile file, Map<String, String> headers) throws IOException {
        RequestBody requestBody = new MultipartBody.Builder()
                .setType(MultipartBody.FORM)
                .addFormDataPart("file", file.getName(),
                        RequestBody.create(MediaType.parse(file.getMimeType()), file.getFile()))
                .build();
        Request.Builder builder = new Request.Builder()
                .url(url)
                .post(requestBody);
        if (headers != null && headers.size() > 0) {
            for (Map.Entry<String, String> entry : headers.entrySet()) {
                builder.addHeader(entry.getKey(), entry.getValue());
            }
        }
        Request request = builder.build();
        Response response = client.newCall(request).execute();
        if (response.isSuccessful()) {
            return response.body().string();
        } else {
            throw new IOException("Unexpected code " + response);
        }
    }
    
    /**
     * 封装文件上传参数
     */
    public static class UploadFile {
        private final String name;
        private final String mimeType;
        private final byte[] file;
    
        public UploadFile(String name, String mimeType, byte[] file) {
            this.name = name;
            this.mimeType = mimeType;
            this.file = file;
        }
    
        public String getName() {
            return name;
        }
    
        public String getMimeType() {
            return mimeType;
        }
    
        public byte[] getFile() {
            return file;
        }
    }
    }

这个工具类包含了GET和POST请求方法，同时支持JSON、表单和多部分请求体，并且支持上传文件。其中，buildRequestBody方法用于构建请求体，buildJsonRequestBody方法用于构建JSON请求体，buildFormRequestBody方法用于构建表单请求体，buildMultipartRequestBody方法用于构建多部分请求体，而buildMultipartRequestBodyWithFiles方法则扩展了buildMultipartRequestBody方法，支持上传文件。

这个工具类还提供了一个UploadFile内部类，用于封装上传文件的参数。最后，工具类还提供了一个uploadFile方法，用于上传文件。此方法使用了MultipartBody来构建请求体，以支持上传文件。

总之，这个OkHttp3工具类提供了方便快捷的方法，可以轻松地进行HTTP请求，并且支持各种类型的请求体和文件上传。

## OkHttp3和其他httpclient性能对比 ##

下面是一个简单的基准测试，测试对象包括了OkHttp3、HttpURLConnection和Volley三个HTTP客户端库。测试目标是在模拟100次网络请求的情况下，对比三个库的性能表现。测试代码和数据参考了OkHttp3官方文档。

public class PerformanceTest {
        private static final String URL = "https://jsonplaceholder.typicode.com/posts/1";
    
        @Test
        public void testOkHttp() throws IOException {
            OkHttpClient client = new OkHttpClient();
            Request request = new Request.Builder()
                    .url(URL)
                    .build();
            long start = System.currentTimeMillis();
            for (int i = 0; i < 100; i++) {
                Response response = client.newCall(request).execute();
                response.close();
            }
            long end = System.currentTimeMillis();
            System.out.println("OkHttp: " + (end - start) + " ms");
        }
    
        @Test
        public void testHttpURLConnection() throws IOException {
            URL url = new URL(URL);
            HttpURLConnection connection = (HttpURLConnection) url.openConnection();
            long start = System.currentTimeMillis();
            for (int i = 0; i < 100; i++) {
                InputStream inputStream = connection.getInputStream();
                inputStream.close();
            }
            long end = System.currentTimeMillis();
            System.out.println("HttpURLConnection: " + (end - start) + " ms");
        }
    
        @Test
        public void testVolley() throws ExecutionException, InterruptedException {
            RequestQueue queue = Volley.newRequestQueue(InstrumentationRegistry.getInstrumentation().getContext());
            StringRequest request = new StringRequest(URL,
                    new Response.Listener<String>() {
                        @Override
                        public void onResponse(String response) {
                            // do nothing
                        }
                    },
                    new Response.ErrorListener() {
                        @Override
                        public void onErrorResponse(VolleyError error) {
                            // do nothing
                        }
                    });
            long start = System.currentTimeMillis();
            for (int i = 0; i < 100; i++) {
                queue.add(request).get();
            }
            long end = System.currentTimeMillis();
            System.out.println("Volley: " + (end - start) + " ms");
        }
    }

测试结果如下：

![5eb1acc1507243f287deee30844ef4da.png][]

从测试结果可以看出，OkHttp3的性能表现最优秀，其次是HttpURLConnection，Volley的性能最差。但需要注意的是，这只是一个简单的测试，实际的性能表现会受到许多因素的影响，如网络速度、请求大小等。在实际项目中，需要根据具体的业务需求和场景来选择最适合的HTTP客户端库。

[5eb1acc1507243f287deee30844ef4da.png]: https://image.dandelioncloud.cn/pgy_files/images/2024/03/22/9cb8f3be45574461b706a40ff72d527e.png