我有一个 REST 服务向我发送一个大的 ISO 文件,REST 服务没有问题。现在我已经编写了一个调用其余服务来获取文件的 Web 应用程序,在客户端(Web 应用程序)端我收到内存不足异常。下面是我的代码
HttpHeaders headers = new HttpHeaders();//1 Line
headers.setAccept(Arrays.asList(MediaType.APPLICATION_OCTET_STREAM));//2 Line
headers.set("Content-Type","application/json");//3 Line
headers.set("Cookie", "session=abc");//4 Line
HttpEntity statusEntity=new HttpEntity(headers);//5 Line
String uri_status=new String("http://"+ip+":8080/pcap/file?fileName={name}");//6 Line
ResponseEntity<byte[]>resp_status=rt.exchange(uri_status, HttpMethod.GET, statusEntity, byte[].class,"File5.iso");//7 Line
我在第 7 行收到内存不足异常,我想我将不得不缓冲并获取部分内容,但不知道如何从服务器获取该文件,该文件的大小约为 500 到 700 MB。谁能帮忙。
异常堆栈:
org.springframework.web.util.NestedServletException: Handler processing failed; nested exception is java.lang.OutOfMemoryError: Java heap space
org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:972)
org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:852)
org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:882)
org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:778)
javax.servlet.http.HttpServlet.service(HttpServlet.java:622)
javax.servlet.http.HttpServlet.service(HttpServlet.java:729)
org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
root cause
java.lang.OutOfMemoryError: Java heap space
java.util.Arrays.copyOf(Arrays.java:3236)
java.io.ByteArrayOutputStream.grow(ByteArrayOutputStream.java:118)
java.io.ByteArrayOutputStream.ensureCapacity(ByteArrayOutputStream.java:93)
java.io.ByteArrayOutputStream.write(ByteArrayOutputStream.java:153)
org.springframework.util.FileCopyUtils.copy(FileCopyUtils.java:113)
org.springframework.util.FileCopyUtils.copyToByteArray(FileCopyUtils.java:164)
org.springframework.http.converter.ByteArrayHttpMessageConverter.readInternal(ByteArrayHttpMessageConverter.java:58)
org.springframework.http.converter.ByteArrayHttpMessageConverter.readInternal(ByteArrayHttpMessageConverter.java:1)
org.springframework.http.converter.AbstractHttpMessageConverter.read(AbstractHttpMessageConverter.java:153)
org.springframework.web.client.HttpMessageConverterExtractor.extractData(HttpMessageConverterExtractor.java:81)
org.springframework.web.client.RestTemplate$ResponseEntityResponseExtractor.extractData(RestTemplate.java:627)
org.springframework.web.client.RestTemplate$ResponseEntityResponseExtractor.extractData(RestTemplate.java:1)
org.springframework.web.client.RestTemplate.doExecute(RestTemplate.java:454)
org.springframework.web.client.RestTemplate.execute(RestTemplate.java:409)
org.springframework.web.client.RestTemplate.exchange(RestTemplate.java:385)
com.pcap.webapp.HomeController.getPcapFile(HomeController.java:186)
我工作正常的服务器端 REST 服务代码是
@RequestMapping(value = URIConstansts.GET_FILE, produces = { MediaType.APPLICATION_OCTET_STREAM_VALUE}, method = RequestMethod.GET)
public void getFile(@RequestParam(value="fileName", required=false) String fileName,HttpServletRequest request,HttpServletResponse response) throws IOException{
byte[] reportBytes = null;
File result=new File("/home/arpit/Documents/PCAP/dummyPath/"+fileName);
if(result.exists()){
InputStream inputStream = new FileInputStream("/home/arpit/Documents/PCAP/dummyPath/"+fileName);
String type=result.toURL().openConnection().guessContentTypeFromName(fileName);
response.setHeader("Content-Disposition", "attachment; filename=" + fileName);
response.setHeader("Content-Type",type);
reportBytes=new byte[100];//New change
OutputStream os=response.getOutputStream();//New change
int read=0;
while((read=inputStream.read(reportBytes))!=-1){
os.write(reportBytes,0,read);
}
os.flush();
os.close();
}
原文由 arpit joshi 发布,翻译遵循 CC BY-SA 4.0 许可协议
我是这样做的。基于这个 Spring Jira 问题 的提示。
从前面提到的 Jira 问题:
春季 5 更新
Spring 5 引入了
WebClient
允许异步(例如非阻塞)http 请求的类。从文档:要在 Spring Boot 中获取
WebClient
,您需要以下依赖项:目前,我坚持使用
RestTemplate
因为我不想引入另一个依赖项只是为了访问WebClient
。