OKhttp实现文件资源下载

功能需求：将网络资源图片下载并存储至本地

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1、添加依赖

OKhttp相比HttpURLConnection和httpClient更高效方便。项目采用gradle构建，首先添加OKhttp相关依赖，依赖如下（可查看jar包的最新版本：http://search.maven.org/ ）：

dependencies {    
    compileOnly "***"
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    compile 'com.squareup.okhttp3:okhttp:3.4.1' 
}

2、方法定义（以网络图片下载为例）

• 传参：   

   1、网络URL参数：photoOnlinePath;

   2、本地存储路径：photoLocalPath

public void downloadPhoto(String photoOnlinePath, String photoLocalPath) {
    File myPath = new File(photoLocalPath);
    String directory = myPath.getParent();
    File mydirectory = new File(directory);
    if (!mydirectory.exists()) {
        //若此目录不存在，则创建之
        mydirectory.mkdirs();
    }
    OkHttpClient okHttpClient = new OkHttpClient();
    okhttp3.Request request = new okhttp3.Request.Builder().get().url(photoOnlinePath).build();
    try{
        Response response = okHttpClient.newCall(request).execute();
        if (!response.isSuccessful()) {
            logger.debug("http request {} connect failed", photoOnlinePath);
        } else {
            logger.info("http request {} connect success，start write in", photoOnlinePath);
            InputStream is;
            is = response.body().byteStream();
            FileOutputStream fos=null;
            try{
                fos = new FileOutputStream(myPath);
                int len;
                byte[] bytes = new byte[1024];
                while ((len = is.read(bytes)) != -1) {
                    fos.write(bytes, 0, len);
                }
            }catch (IOException oue){
                logger.debug("save photo {} to local dir {} failed!", photoOnlinePath, photoLocalPath);
            }finally {
                if (is != null) {
                    try{
                        is.close();
                    }catch (IOException isclose){
                        logger.error("close InputStream failed");
                    }
                }
                if (fos!=null){
                    try{
                        fos.close();
                    }catch (IOException fosclose){
                        logger.error("close FileOutputStream failed");
                    }
                }
            }
        }
    }catch (IOException e){
        logger.error("http request {} connect failed", photoOnlinePath);
    }
}