在 Struts2 中提交响应后无法调用 sendRedirect()
Cannot call sendRedirect() after the response has been committed in Struts2
我在一个小型网络应用程序中使用 struts2 和 jasper 报告。尝试导出报告时出现以下错误。报告导出成功，但日志中打印错误，struts执行操作后也无法重定向到成功页面。
我已经通过互联网搜索了这个，但我无法澄清这一点。谁能帮我澄清一下。
ERROR Dispatcher - Exception occurred during processing request: Cannot call sendRedirect() after the response has been committed
java.lang.IllegalStateException: Cannot call sendRedirect() after the response has been committed
at org.apache.catalina.connector.ResponseFacade.sendRedirect(ResponseFacade.java:482)
at javax.servlet.http.HttpServletResponseWrapper.sendRedirect(HttpServletResponseWrapper.java:137)
at org.springframework.security.web.context.SaveContextOnUpdateOrErrorResponseWrapper.sendRedirect (SaveContextOnUpdateOrErrorResponseWrapper.java:74)
at org.apache.struts2.dispatcher.ServletRedirectResult.sendRedirect(ServletRedirectResult.java:243)
at org.apache.struts2.dispatcher.ServletRedirectResult.doExecute(ServletRedirectResult.java:226)
at org.apache.struts2.dispatcher.StrutsResultSupport.execute(StrutsResultSupport.java:186)
at org.apache.struts2.dispatcher.ServletRedirectResult.execute(ServletRedirectResult.java:161)
at com.opensymphony.xwork2.DefaultActionInvocation.executeResult(DefaultActionInvocation.java:367)
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:271)
at org.apache.struts2.interceptor.debugging.DebuggingInterceptor.intercept(DebuggingInterceptor.java:256)
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:242)
at com.opensymphony.xwork2.interceptor.DefaultWorkflowInterceptor.doIntercept(DefaultWorkflowInterceptor.java:176)
at com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:98)
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:242)
at com.opensymphony.xwork2.validator.ValidationInterceptor.doIntercept(ValidationInterceptor.java:265)
at org.apache.struts2.interceptor.validation.AnnotationValidationInterceptor.doIntercept (AnnotationValidationInterceptor.java:68)
<struts>
<package name="user" namespace="/" extends="struts-default">
<action name="testJPReport" class="testUserSupport" method="exportReportAsPdf">
<result name="success">report.jsp</result>
</action>
</package>
</struts>
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans-3.1.xsd">
<bean id="testUserSupport"
class="net.lavanya.app.lav.report.web.TestUserAction">
</bean>
public class TestUserAction extends ExportSupport{
public String exportReportAsPdf() {
Map<String, Object> param = new HashMap<>();
try {
DataBeanMaker dataBeanMaker = new DataBeanMaker();
ArrayList<Test> dataBeanList = dataBeanMaker.getTestDataBeanList();
processReport(ReportTypeEnum.PDF, dataBeanList, "test", param);
} catch (Exception exception) {
exception.printStackTrace();
}
return SUCCESS;
}
}
package net.test.app.report.web;
import com.opensymphony.xwork2.ActionSupport;
import net.sf.jasperreports.engine.*;
import net.sf.jasperreports.engine.data.JRBeanCollectionDataSource;
import net.sf.jasperreports.engine.design.JasperDesign;
import net.sf.jasperreports.engine.xml.JRXmlLoader;
import org.apache.struts2.interceptor.ServletRequestAware;
import org.apache.struts2.interceptor.ServletResponseAware;
import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.InputStream;
import java.util.List;
import java.util.Map;
public class ExportSupport extends ActionSupport implements ServletResponseAware, ServletRequestAware {
private HttpServletResponse httpServletResponse;
private HttpServletRequest httpServletRequest;
private String contentType = "APPLICATION/OCTET-STREAM";
@Override
public void setServletResponse(HttpServletResponse httpServletResponse) {
this.httpServletResponse = httpServletResponse;
}
@Override
public void setServletRequest(HttpServletRequest httpServletRequest) {
this.httpServletRequest = httpServletRequest;
}
public void processReport(ReportTypeEnum reportTypeEnum, List<?> beansList, String reportName, Map<String, Object> parameters) throws Exception {
switch (reportTypeEnum) {
case PDF:
processReportAsPDF(beansList, reportName, parameters);
break;
default:
throw new RuntimeException("Un supported report type");
}
}
private void processReportAsPDF(List<?> beansList, String reportName, Map<String, Object> parameters) throws Exception {
System.out.println(">>>>>>>Start processing of pdf report!");
JRBeanCollectionDataSource beanColDataSource = new JRBeanCollectionDataSource(beansList);
JasperDesign jasperDesign = JRXmlLoader.load(getJasperFilePath(reportName));
JasperReport jasperReport = JasperCompileManager.compileReport(jasperDesign);
JasperPrint jasperPrint = JasperFillManager.fillReport(jasperReport, parameters, beanColDataSource);
setResponseHeaderData(reportName, ReportTypeEnum.PDF);
ServletOutputStream sos = httpServletResponse.getOutputStream();
JasperExportManager.exportReportToPdfStream(jasperPrint, sos);
sos.flush();
sos.close();
httpServletResponse.getOutputStream().flush();
httpServletResponse.getOutputStream().close();
System.out.println(">>>>>>>End processing of pdf report!");
return;
}
private InputStream getJasperFilePath(String reportName) throws FileNotFoundException {
System.out.println(">>>>>>> Path : " + httpServletRequest.getSession().getServletContext().getRealPath("/reports/" + reportName + ".jrxml"));
return new FileInputStream(httpServletRequest.getSession().getServletContext().getRealPath("/reports/" + reportName + ".jrxml"));
}
private void setResponseHeaderData(String reportName, ReportTypeEnum reportTypeEnum) {
httpServletResponse.setContentType(contentType);
StringBuilder headerBuilder = new StringBuilder();
headerBuilder.append("Attachment;Filename=").append("\"").append(reportName).append(".").
append(reportTypeEnum.getReportType()).append("\"");
httpServletResponse.setHeader("Content-Disposition", headerBuilder.toString());
System.out.println(">>>>>>>End of setting response headers for report download");
}
}
我在您的代码中找不到 sendRedirect。
任何方式请考虑每个 HTTP 请求只有一个 HTTP 响应您可能需要在客户端的一些 JavaScript 解决方案。
导出操作，或通常 stream 结果类型操作应如下所示：
@Action(value = "sample-export", results = { @Result(name = "success", type = "stream", params = {
"inputName", "inputStream",
"contentType", "${exportContentType}; charset=UTF-8",
"Content-Disposition", "attachment; filename=\"${filename}\"",
"contentDisposition","attachment; filename=\"${filename}\"",
"bufferSize", "2048" }) })
public String export() throws ClientException {
inputStream = exportInputStream();
return SUCCESS;
}
//Setter and getters for inputStream (java.io.InputStream)
如您所见，返回成功不会也不应该将用户重定向到新页面，用户发送请求并获得流（例如 PDF）作为结果。
如果您想要重定向，您需要通过 javascript 执行更多操作，或者更改下载步骤，请参阅 Is it possible in Struts 2 to have a result that downloads a file (stream) *and* redirects? 这可能会有所帮助。
通过更改下载步骤，我的意思是您可以将文件保存在服务器上的临时位置，将用户重定向到最终页面并将下载内容 link 放在那里。
我在一个小型网络应用程序中使用 struts2 和 jasper 报告。尝试导出报告时出现以下错误。报告导出成功，但日志中打印错误，struts执行操作后也无法重定向到成功页面。
我已经通过互联网搜索了这个，但我无法澄清这一点。谁能帮我澄清一下。
ERROR Dispatcher - Exception occurred during processing request: Cannot call sendRedirect() after the response has been committed
java.lang.IllegalStateException: Cannot call sendRedirect() after the response has been committed
at org.apache.catalina.connector.ResponseFacade.sendRedirect(ResponseFacade.java:482)
at javax.servlet.http.HttpServletResponseWrapper.sendRedirect(HttpServletResponseWrapper.java:137)
at org.springframework.security.web.context.SaveContextOnUpdateOrErrorResponseWrapper.sendRedirect (SaveContextOnUpdateOrErrorResponseWrapper.java:74)
at org.apache.struts2.dispatcher.ServletRedirectResult.sendRedirect(ServletRedirectResult.java:243)
at org.apache.struts2.dispatcher.ServletRedirectResult.doExecute(ServletRedirectResult.java:226)
at org.apache.struts2.dispatcher.StrutsResultSupport.execute(StrutsResultSupport.java:186)
at org.apache.struts2.dispatcher.ServletRedirectResult.execute(ServletRedirectResult.java:161)
at com.opensymphony.xwork2.DefaultActionInvocation.executeResult(DefaultActionInvocation.java:367)
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:271)
at org.apache.struts2.interceptor.debugging.DebuggingInterceptor.intercept(DebuggingInterceptor.java:256)
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:242)
at com.opensymphony.xwork2.interceptor.DefaultWorkflowInterceptor.doIntercept(DefaultWorkflowInterceptor.java:176)
at com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:98)
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:242)
at com.opensymphony.xwork2.validator.ValidationInterceptor.doIntercept(ValidationInterceptor.java:265)
at org.apache.struts2.interceptor.validation.AnnotationValidationInterceptor.doIntercept (AnnotationValidationInterceptor.java:68)
<struts>
<package name="user" namespace="/" extends="struts-default">
<action name="testJPReport" class="testUserSupport" method="exportReportAsPdf">
<result name="success">report.jsp</result>
</action>
</package>
</struts>
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans-3.1.xsd">
<bean id="testUserSupport"
class="net.lavanya.app.lav.report.web.TestUserAction">
</bean>
public class TestUserAction extends ExportSupport{
public String exportReportAsPdf() {
Map<String, Object> param = new HashMap<>();
try {
DataBeanMaker dataBeanMaker = new DataBeanMaker();
ArrayList<Test> dataBeanList = dataBeanMaker.getTestDataBeanList();
processReport(ReportTypeEnum.PDF, dataBeanList, "test", param);
} catch (Exception exception) {
exception.printStackTrace();
}
return SUCCESS;
}
}
package net.test.app.report.web;
import com.opensymphony.xwork2.ActionSupport;
import net.sf.jasperreports.engine.*;
import net.sf.jasperreports.engine.data.JRBeanCollectionDataSource;
import net.sf.jasperreports.engine.design.JasperDesign;
import net.sf.jasperreports.engine.xml.JRXmlLoader;
import org.apache.struts2.interceptor.ServletRequestAware;
import org.apache.struts2.interceptor.ServletResponseAware;
import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.InputStream;
import java.util.List;
import java.util.Map;
public class ExportSupport extends ActionSupport implements ServletResponseAware, ServletRequestAware {
private HttpServletResponse httpServletResponse;
private HttpServletRequest httpServletRequest;
private String contentType = "APPLICATION/OCTET-STREAM";
@Override
public void setServletResponse(HttpServletResponse httpServletResponse) {
this.httpServletResponse = httpServletResponse;
}
@Override
public void setServletRequest(HttpServletRequest httpServletRequest) {
this.httpServletRequest = httpServletRequest;
}
public void processReport(ReportTypeEnum reportTypeEnum, List<?> beansList, String reportName, Map<String, Object> parameters) throws Exception {
switch (reportTypeEnum) {
case PDF:
processReportAsPDF(beansList, reportName, parameters);
break;
default:
throw new RuntimeException("Un supported report type");
}
}
private void processReportAsPDF(List<?> beansList, String reportName, Map<String, Object> parameters) throws Exception {
System.out.println(">>>>>>>Start processing of pdf report!");
JRBeanCollectionDataSource beanColDataSource = new JRBeanCollectionDataSource(beansList);
JasperDesign jasperDesign = JRXmlLoader.load(getJasperFilePath(reportName));
JasperReport jasperReport = JasperCompileManager.compileReport(jasperDesign);
JasperPrint jasperPrint = JasperFillManager.fillReport(jasperReport, parameters, beanColDataSource);
setResponseHeaderData(reportName, ReportTypeEnum.PDF);
ServletOutputStream sos = httpServletResponse.getOutputStream();
JasperExportManager.exportReportToPdfStream(jasperPrint, sos);
sos.flush();
sos.close();
httpServletResponse.getOutputStream().flush();
httpServletResponse.getOutputStream().close();
System.out.println(">>>>>>>End processing of pdf report!");
return;
}
private InputStream getJasperFilePath(String reportName) throws FileNotFoundException {
System.out.println(">>>>>>> Path : " + httpServletRequest.getSession().getServletContext().getRealPath("/reports/" + reportName + ".jrxml"));
return new FileInputStream(httpServletRequest.getSession().getServletContext().getRealPath("/reports/" + reportName + ".jrxml"));
}
private void setResponseHeaderData(String reportName, ReportTypeEnum reportTypeEnum) {
httpServletResponse.setContentType(contentType);
StringBuilder headerBuilder = new StringBuilder();
headerBuilder.append("Attachment;Filename=").append("\"").append(reportName).append(".").
append(reportTypeEnum.getReportType()).append("\"");
httpServletResponse.setHeader("Content-Disposition", headerBuilder.toString());
System.out.println(">>>>>>>End of setting response headers for report download");
}
}
我在您的代码中找不到 sendRedirect。
任何方式请考虑每个 HTTP 请求只有一个 HTTP 响应您可能需要在客户端的一些 JavaScript 解决方案。
导出操作，或通常 stream 结果类型操作应如下所示：
@Action(value = "sample-export", results = { @Result(name = "success", type = "stream", params = {
"inputName", "inputStream",
"contentType", "${exportContentType}; charset=UTF-8",
"Content-Disposition", "attachment; filename=\"${filename}\"",
"contentDisposition","attachment; filename=\"${filename}\"",
"bufferSize", "2048" }) })
public String export() throws ClientException {
inputStream = exportInputStream();
return SUCCESS;
}
//Setter and getters for inputStream (java.io.InputStream)
如您所见，返回成功不会也不应该将用户重定向到新页面，用户发送请求并获得流（例如 PDF）作为结果。
如果您想要重定向，您需要通过 javascript 执行更多操作，或者更改下载步骤，请参阅 Is it possible in Struts 2 to have a result that downloads a file (stream) *and* redirects? 这可能会有所帮助。 通过更改下载步骤，我的意思是您可以将文件保存在服务器上的临时位置，将用户重定向到最终页面并将下载内容 link 放在那里。