Struts2 流下载有问题，大侠们请出手相助

小可同学 2010-12-21 07:56:17

我用iText生成PDF文件,这问题真的很头疼，一直在疼，问题能解决了，就打会CF去，休息休息。

/*action*/

public String pdf() {

	try {

		Document document = new Document();

		ByteArrayOutputStream os = new ByteArrayOutputStream();

		PdfWriter.getInstance(document, os);

		document.open();

		document.add(new Paragraph("Hello World"));

		document.close();

		os.close();

		pdfStream = new ByteArrayInputStream(os.toByteArray());

	} catch (Exception e) {

		e.printStackTrace();

	}

	return "pdf";

}

/*struts.xml*/

<action name="pdf_*" class="action.PdfAction" method="{1}">

	<result name="pdf" type="stream">

		<param name="contentType">application/pdf</param>

		<param name="inputName">pdfStream</param>

		<param name="contentDisposition">filename="demo.pdf"</param>

		<param name="bufferSize">1024</param>

	</result>

</action>

/*页面*/

<s:form action="pdf_pdf" method="post">

	<s:submit value="下载Demo_pdf文件"/>

</s:form>

页面点击下载的时候出异常：

java.lang.IllegalStateException: getWriter() has already been called for this response

	org.apache.catalina.connector.Response.getOutputStream(Response.java:579)

	org.apache.catalina.connector.ResponseFacade.getOutputStream(ResponseFacade.java:183)

	org.apache.struts2.dispatcher.StreamResult.doExecute(StreamResult.java:278)

	org.apache.struts2.dispatcher.StrutsResultSupport.execute(StrutsResultSupport.java:186)

	com.opensymphony.xwork2.DefaultActionInvocation.executeResult(DefaultActionInvocation.java:373)

	com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:277)

	com.opensymphony.xwork2.interceptor.DefaultWorkflowInterceptor.doIntercept(DefaultWorkflowInterceptor.java:176)

	com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:98)

	com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:248)

	com.opensymphony.xwork2.validator.ValidationInterceptor.doIntercept(ValidationInterceptor.java:263)

	org.apache.struts2.interceptor.validation.AnnotationValidationInterceptor.doIntercept(AnnotationValidationInterceptor.java:68)

	com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:98)

	com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:248)

	com.opensymphony.xwork2.interceptor.ConversionErrorInterceptor.intercept(ConversionErrorInterceptor.java:133)

	com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:248)

	com.opensymphony.xwork2.interceptor.ParametersInterceptor.doIntercept(ParametersInterceptor.java:207)

	com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:98)

	com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:248)

	com.opensymphony.xwork2.interceptor.ParametersInterceptor.doIntercept(ParametersInterceptor.java:207)

	com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:98)

	com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:248)

	com.opensymphony.xwork2.interceptor.StaticParametersInterceptor.intercept(StaticParametersInterceptor.java:190)

	com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:248)

	org.apache.struts2.interceptor.MultiselectInterceptor.intercept(MultiselectInterceptor.java:75)

	com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:248)

	org.apache.struts2.interceptor.CheckboxInterceptor.intercept(CheckboxInterceptor.java:94)

	com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:248)

	org.apache.struts2.interceptor.FileUploadInterceptor.intercept(FileUploadInterceptor.java:243)

	com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:248)

	com.opensymphony.xwork2.interceptor.ModelDrivenInterceptor.intercept(ModelDrivenInterceptor.java:100)

	com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:248)

	com.opensymphony.xwork2.interceptor.ScopedModelDrivenInterceptor.intercept(ScopedModelDrivenInterceptor.java:141)

	com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:248)

	org.apache.struts2.interceptor.debugging.DebuggingInterceptor.intercept(DebuggingInterceptor.java:267)

	com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:248)

	com.opensymphony.xwork2.interceptor.ChainingInterceptor.intercept(ChainingInterceptor.java:142)

	com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:248)

	com.opensymphony.xwork2.interceptor.PrepareInterceptor.doIntercept(PrepareInterceptor.java:166)

	com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:98)

	com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:248)

	com.opensymphony.xwork2.interceptor.I18nInterceptor.intercept(I18nInterceptor.java:176)

	com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:248)

	org.apache.struts2.interceptor.ServletConfigInterceptor.intercept(ServletConfigInterceptor.java:164)

	com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:248)

	com.opensymphony.xwork2.interceptor.AliasInterceptor.intercept(AliasInterceptor.java:190)

	com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:248)

	com.opensymphony.xwork2.interceptor.ExceptionMappingInterceptor.intercept(ExceptionMappingInterceptor.java:187)

	com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:248)

	org.apache.struts2.impl.StrutsActionProxy.execute(StrutsActionProxy.java:52)

	org.apache.struts2.dispatcher.Dispatcher.serviceAction(Dispatcher.java:485)

	org.apache.struts2.dispatcher.ng.ExecuteOperations.executeAction(ExecuteOperations.java:77)

	org.apache.struts2.dispatcher.ng.filter.StrutsPrepareAndExecuteFilter.doFilter(StrutsPrepareAndExecuteFilter.java:91)