java - 关闭 StreamReader

Question

从服务器获得响应(通过发送 http 请求)后，我尝试按如下方式获取内容:

HttpEntity entity = response.getEntity();

    if (entity == null) {
        ...
    }

    String content;
    try {
        Reader reader = new BufferedReader(new InputStreamReader(entity.getContent(), "UTF-8"));
        content = IOUtils.toString(reader);
        reader.close();
        EntityUtils.consume(entity);
    } catch (IOException e) {
        ...
    }

是否有必要关闭阅读器(reader.close())？或者 EntityUtils.consume(entity) 就足够了？

Answer 1

您可以使用try-with-resources-语句:

try(Reader reader = new BufferedReader(new InputStreamReader(entity.getContent(), "UTF-8"))) {
    content = IOUtils.toString(reader);
    EntityUtils.consume(entity);
} catch (IOException e) {
    ...
}

这已经为您关闭了阅读器。

对于 Java 6，您应该使用以下内容:

Reader reader = null;
try {
    reader = new BufferedReader(new InputStreamReader(entity.getContent(), "UTF-8"));
    content = IOUtils.toString(reader);
    EntityUtils.consume(entity);
} catch (IOException e) {
    ...
} finally {
    if(reader != null){
        try {
            reader.close();
        } catch(IOException e){
            // can not be closed
        }
    }
}