从大型文件处理的休息模板获取打开的输入流(Get opened input stream from rest template for large file processing)

从大型文件处理的休息模板获取打开的输入流(Get opened input stream from rest template for large file processing)

我正在寻找一种方法从rest模板获取打开的输入流 - 我试图使用ResponseExtractor，但是在返回之前流正在关闭，如下所示：

https://jira.spring.io/browse/SPR-7357

“请注意，您不能简单地从提取器中返回InputStream，因为到execute方法返回时，基础连接和流已经关闭”

我希望有一种方法，我不需要在其他模板中直接写入输出流。

I am looking for a way to get opened input stream from rest template - I was trying to used ResponseExtractor, but the stream is getting closed before returning, as written here:

https://jira.spring.io/browse/SPR-7357

"Note that you cannot simply return the InputStream from the extractor, because by the time the execute method returns, the underlying connection and stream are already closed"

I hope that there is a way and I will not have to write to my output stream directly in the rest template.

最满意答案

我没有找到办法做到这一点，该流正在关闭。 作为解决方法，我创建了以下代码：

public interface ResourceReader { void read(InputStream content); }

执行如下：

public class StreamResourceReader implements ResourceReader { private HttpServletResponse response; public StreamResourceReader(HttpServletResponse response) { this.response = response; } @Override public void read(InputStream content) { try { IOUtils.copy(content, response.getOutputStream()); } catch (IOException e) { throw new IllegalStateException(e); } } }

然后在控制器中：

@RequestMapping(value = "document/{objectId}") public void getDocumentContent(@PathVariable String objectId, HttpServletResponse response) { ResourceReader reader = new StreamResourceReader(response); service.readDocumentContent(objectId, reader); }

呼叫休息模板：

restTemplate.execute(uri, HttpMethod.GET, null, new StreamResponseExtractor(reader));

和字符串响应提取器：

@Override public ResponseEntity extractData(ClientHttpResponse response) throws IOException { reader.read(response.getBody()); return null; }

它就像一个魅力！ :)

I didn't find a way to do it, the stream is always getting closed. As a workaround I created the following code:

public interface ResourceReader { void read(InputStream content); }

with the following implementation:

public class StreamResourceReader implements ResourceReader { private HttpServletResponse response; public StreamResourceReader(HttpServletResponse response) { this.response = response; } @Override public void read(InputStream content) { try { IOUtils.copy(content, response.getOutputStream()); } catch (IOException e) { throw new IllegalStateException(e); } } }

then in controller:

@RequestMapping(value = "document/{objectId}") public void getDocumentContent(@PathVariable String objectId, HttpServletResponse response) { ResourceReader reader = new StreamResourceReader(response); service.readDocumentContent(objectId, reader); }

call to rest template:

restTemplate.execute(uri, HttpMethod.GET, null, new StreamResponseExtractor(reader));

and the string response extractor:

@Override public ResponseEntity extractData(ClientHttpResponse response) throws IOException { reader.read(response.getBody()); return null; }

and it works like a charm! :)