使用httpclient下载远程文件

有些时候我们需要使用httclient直接从网络获取一个文件
httpclient底层获取文件的方式仍然是封装的流,但是使用起来会比较方便，可以设置代理等web设施
示例代码如下

CloseableHttpClient client = HttpClients.createDefault();
RequestConfig config = null;
//使用代理

if(null != proxy && StringUtils.isNotBlank(proxy.ip) && proxy.port > 0){
    HttpHost proxy = new HttpHost(proxy.ip, proxy.port);  
    config = RequestConfig.custom().setProxy(proxy).build(); 
}else{
//没有代理，使用默认值
    config = RequestConfig.custom().build();
}
//目标文件url
HttpGet httpGet = new HttpGet(url);
httpGet.setConfig(config);
//下载需登陆，设置登陆后的cookie
httpGet.addHeader("Cookie", cookie);

try {
    HttpResponse respone = client.execute(httpGet);
    if(respone.getStatusLine().getStatusCode() != HttpStatus.SC_OK){
        return ;
    }
    HttpEntity entity = respone.getEntity();
    if(entity != null) {
        InputStream is = entity.getContent();
        File file = new File("目标文件生成路径");
        FileOutputStream fos = new FileOutputStream(file); 
        byte[] buffer = new byte[4096];
        int len = -1;
        while((len = is.read(buffer) )!= -1){
            fos.write(buffer, 0, len);
        }
        fos.close();
        is.close();
        files.add(file);
    }
} catch (Exception e) {
    
}finally{
    try {
        client.close();
    } catch (IOException e) {
        e.printStackTrace();
    }
}