使用Java从服务器下载大文件时出错

我是Java中的文件处理新手 . 我编写了一个代码，可以从服务器下载文件 . 该代码适用于大小为70 MB的文件 . 如果下载大文件，则会抛出异常 .

SRVE0260E：服务器无法使用为您的应用程序指定的错误页面来处理下面打印的原始异常 . 原始异常：错误消息：java.lang.OutOfMemoryError错误代码：500目标Servlet：null错误堆栈：java.lang.OutOfMemoryError“at app.web.webcontroller.webAction.DownloadCsvAction.execute（DownloadCsvAction.java:49）”“at at org.apache.struts.action.RequestProcessor.processActionPerform（RequestProcessor.java:422）“”at org.apache.struts.action.RequestProcessor.process（RequestProcessor.java:228）“”at org.apache.struts.action . ActionServlet.process（ActionServlet.java:1164）“”at org.apache.struts.action.ActionServlet.doGet（ActionServlet.java:397）“”at javax.servlet.http.HttpServlet.service（HttpServlet.java:718） “”在com.ibm.ws的javax.servlet.http.HttpServlet.service（HttpServlet.java:831）“”com.ibm.ws.webcontainer.servlet.ServletWrapper.service（ServletWrapper.java:1530）“” .webcontainer.servlet.ServletWrapper.service（ServletWrapper.java:1470）“”at com.ibm.ws.webcontainer.filter.WebAppFilterChain.doFilter（WebAppFilterChain.java:131）“”at app.systemController.RequestTimer在com.ibm.ws.webcontainer.filter.FilterInstanceWrapper.doFilter（FilterInstanceWrapper.java:188）的app.systemController.RequestTimerFilter.doFilter（RequestTimerFilter.java:61）“”上的Filter.doFilter_http（RequestTimerFilter.java:73）“” “”com.ibm.ws.webcontainer.filter.WebAppFilterChain.doFilter（WebAppFilterChain.java:116）“”at com.ibm.ws.webcontainer.filter.WebAppFilterChain._doFilter（WebAppFilterChain.java:77）“”at com .ibm.ws.webcontainer.filter.WebAppFilterManager.doFilter（WebAppFilterManager.java:858）“”在com.ibm.ws的com.ibm.ws.webcontainer.servlet.ServletWrapper.handleRequest（ServletWrapper.java:824）“” .webcontainer.servlet.ServletWrapper.handleRequest（ServletWrapper.java:458）“”在com.ibm.ws.webcontainer.servlet的com.ibm.ws.webcontainer.servlet.ServletWrapperImpl.handleRequest（ServletWrapperImpl.java:175）“” .cacheServletWrapper.handleRequest（CacheServletWrapper.java:91）“”在com.ibm.ws.webcon的com.ibm.ws.webcontainer.WebContainer.handleRequest（WebContainer.java:862）“” tainer.WSWebContainer.handleRequest（WSWebContainer.java:1583）“”at com.ibm.ws.webcontainer.channel.WCChannelLink.ready（WCChannelLink.java:178）“”at com.ibm.ws.http.channel.inbound . impl.HttpInboundLink.handleDiscrimination（HttpInboundLink.java:455）“”在com.ibm.ws.http的com.ibm.ws.http.channel.inbound.impl.HttpInboundLink.handleNewInformation(HttpInboundLink.java:384）“” . 在com.ibm.io上的com.ibm.ws.tcp.channel.impl.AioReadCompletionListener.futureCompleted(AioReadCompletionListener.java:165）“”中的channel.inbound.impl.HttpICLReadCallback.complete（HttpICLReadCallback.java:83）“” . 在com.ibm.io.async.AsyncFuture.completed（AsyncFuture . java：138）“”at com.ibm.io.async.ResultHandler.complete（ResultHandler.java:204）“”at com.ibm.io.async.ResultHandler.runEventProcessingLoop（ResultHandler.java:775）“”at com .ibm.io.async.Result处理程序$ 2.run（ResultHandler.java:905）“”在com.ibm.ws.util.ThreadPool $ Worker.run（ThreadPool.java:1550）“错误页面异常：错误消息：java.lang.IllegalStateException：SRVE0199E： OutputStream已经获得错误代码：0目标Servlet：null错误堆栈：java.lang.IllegalStateException：SRVE0199E：OutputStream已经“在com.ibm.ws.webcontainer.srt.SRTServletResponse.getWriter（SRTServletResponse.java:719）”处获得org.apache.jasper.runtime.JspWriterImpl.initOut（JspWriterImpl.java:187）“”org.apache.jasper.runtime.JspWriterImpl.flushBuffer(JspWriterImpl.java:175）“”at org.apache.jasper.runtime . PageContextImpl.release（PageContextImpl.java:262）“”org.apache.jasper.runtime.JspFactoryImpl.internalReleasePageContext（JspFactoryImpl.java:177）“”at org.apache.jasper.runtime.JspFactoryImpl.releasePageContext（JspFactoryImpl.java： 137）“”在com.ibm._jsp._Error500._jspService（_Error500.java:177）“”at com.ibm.ws.jsp.runtime.HttpJspBase.service（HttpJspBase.java:98）“”at ja vax.servlet.http.HttpServlet.service（HttpServlet.java:831）“”at atcom.ibm.ws.webcontainer.servlet.ServletWrapper.service（ServletWrapper.java:1530）“”在com.ibm的com.ibm.ws.webcontainer.servlet.ServletWrapper.service（ServletWrapper.java:1470）“” . ws.webcontainer.filter.WebAppFilterChain.doFilter（WebAppFilterChain.java:104）“”位于com.ibm.ws.webcontainer的com.ibm.ws.webcontainer.filter.WebAppFilterChain._doFilter（WebAppFilterChain.java:77）“” . filter.WebAppFilterManager.doFilter（WebAppFilterManager.java:858）“”位于com.ibm.ws.webcontainer.servlet.ServletWrapper的com.ibm.ws.webcontainer.servlet.ServletWrapper.handleRequest（ServletWrapper.java:824）“” . handleRequest（ServletWrapper.java:458）“”at com.ibm.ws.webcontainer.servlet.ServletWrapperImpl.handleRequest（ServletWrapperImpl.java:175）“”at com.ibm.wsspi.webcontainer.servlet.GenericServletWrapper.handleRequest（GenericServletWrapper . java：121）“”at com.ibm.ws.jsp.webcontainerext.AbstractJSPExtensionServletWrapper.handleRequest（AbstractJSPExtensionServletWrapper.java:239）“”at com.ibm.ws.webcontaine r.webapp.WebAppRequestDispatcher.forward（WebAppRequestDispatcher.java:330）“”位于com.ibm.ws.webcontainer.servlet的com.ibm.ws.webcontainer.webapp.WebApp.sendError（WebApp.java:3209）“” . ServletWrapper.handleRequest（ServletWrapper.java:987）“”at com.ibm.ws.webcontainer.servlet.ServletWrapper.handleRequest（ServletWrapper.java:458）“”at com.ibm.ws.webcontainer.servlet.ServletWrapperImpl.handleRequest（ ServletWrapperImpl.java:175）“”at com.ibm.ws.webcontainer.servlet.CacheServletWrapper.handleRequest（CacheServletWrapper.java:91）“”at com.ibm.ws.webcontainer.WebContainer.handleRequest（WebContainer.java:862） “”com.ibm.ws.webcontainer.WSWebContainer.handleRequest（WSWebContainer.java:1583）“”at com.ibm.ws.webcontainer.channel.WCChannelLink.ready（WCChannelLink.java:178）“”at com.ibm .ws.http.channel.inbound.impl.HttpInboundLink.handleDiscrimination（HttpInboundLink.java:455）“”在com.ibm.ws.http.channel.inbound.impl.HttpInboundLink.handleNewInformation（HttpInboundLink.java:384）“”在com .ibm.ws.http.channel.inbound.impl.HttpICLReadCallback.complete（HttpICLReadCallback.java:83）“”在com.ibm.ws.tcp.channel.impl.AioReadCompletionListener.futureCompleted（AioReadCompletionListener.java:165）“” at com.ibm.io.async.AbstractAsyncFuture.invokeCallback（AbstractAsyncFuture.java:217）“”at com.ibm.io.async.AsyncChannelFuture.fireCompletionActions（AsyncChannelFuture.java:161）“”at com.ibm.io.async .AsyncFuture.completed（AsyncFuture.java:138）“”at com.ibm.io.async.ResultHandler.complete（ResultHandler.java:204）“”at com.ibm.io.async.ResultHandler.runEventProcessingLoop（ResultHandler.java ：775）“”在com.ibm.io.async.ResultHandler $ 2.run（ResultHandler.java:905）“”在com.ibm.ws.util.ThreadPool $ Worker.run（ThreadPool.java:1550）“

此异常将打印在下载的文件中，而不是原始数据 .

response.setHeader("Content-Disposition","attachment;filename=\""+fileName+"\"");
        response.setContentType("application/octet-stream");
         File downloadFile = new File(fileUrl\fileName);
         OutputStream out = response.getOutputStream();
         FileInputStream in = new FileInputStream(downloadFile); 
         int size=(int)downloadFile.length()+1;
         byte[] buffer = new byte[size];
         int length;
         while ((length = in.read(buffer)) != -1){
            out.write(buffer, 0, length);
         }
         in.close();
         out.flush();

另外在代码段中，请告诉我是否有任何方法可以优化我的代码以使其更快 .