Android OKhttp使用（下载和上传文件）

Android okhttp的使用

首先在build.gradle中引入okhttp

    implementation 'com.squareup.okhttp3:okhttp:3.14.2'
    implementation 'com.squareup.okio:okio:1.17.4'

下面是demo（用okthttp下载网络上的资源）

//下载路径，如果路径无效了，可换成你的下载路径
final String url = "http://sancloud.com/resource/" + file;
Request request = new Request.Builder().url(url).build();
new OkHttpClient().newCall(request).enqueue(new Callback() {
    
    
    @Override
    public void onFailure(Call call, IOException e) {
    
    
        // 下载失败
        e.printStackTrace();
        Log.i("DOWNLOAD","download failed");
    }

    @Override
    public void onResponse(Call call, Response response) throws IOException {
    
    
        Sink sink = null;
        BufferedSink bufferedSink = null;
        String filename = url.substring(url.lastIndexOf("/") + 1);
        //这是里的mContext是我提前获取了android的context
        File localFile = mContext.getFilesDir()+File.separator+filename 
        try {
    
    
            sink = Okio.sink(localFile);
            bufferedSink = Okio.buffer(sink);
            bufferedSink.writeAll(response.body().source());
            bufferedSink.close();
            }
        } catch (Exception e) {
    
    
            e.printStackTrace();
        } finally {
    
    
            if (bufferedSink != null) {
    
    
                bufferedSink.close();
            }
        }
    }
});

用okthttp将资源上传至网络

        // 获得输入框中的路径
        File file = new File(path);
        OkHttpClient client = new OkHttpClient();
        // 上传文件使用MultipartBody.Builder
        RequestBody requestBody = new MultipartBody.Builder()
                .setType(MultipartBody.FORM)
                // 提交普通字段
                .addFormDataPart("id", String.valueOf(id)) 
                // 提交文件，第一个参数是键（key="第一个参数"），第二个参数是文件名，第三个是一个RequestBody
                .addFormDataPart("file", file.getName(), 
               RequestBody.create(MediaType.parse("multipart/form-data"), file)) 
                .build();
        // POST请求
        Request request = new Request.Builder()
                .url("http://sancloud.com:9111/MobileCenter/upload")
                .post(requestBody)
                .build();
        client.newCall(request).enqueue(new Callback() {
    
    
            @Override
            public void onFailure(Call call, IOException e) {
    
    
                LogUtils.w("文件上传出现问题");
            }

            @Override
            public void onResponse(Call call, Response response) throws IOException {
    
    
                LogUtils.i("log文件上传成功");
            }
        });