这是我的索引页面：
<%@ page language="java" contentType="text/html; charset=ISO-8859-1"
pageEncoding="ISO-8859-1"%>
<%@ taglib prefix="s" uri="/struts-tags" %>
<html>
<head>
<meta http-equiv="SContent-Type" content="text/html; charset=ISO-8859-1">
<title>Insert title here</title>
</head>
<body>
<s:form action="clickupload" method="post" enctype="multipart/form-data" >
<s:file name="myFile"></s:file>
<s:submit value="Upload"/>
</s:form>
</body>
</html>
struts.xml中
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE struts PUBLIC
"-//Apache Software Foundation//DTD Struts Configuration 2.3//EN"
"http://struts.apache.org/dtds/struts-2.3.dtd">
<struts>
<include file="struts-default.xml"/>
<constant name="struts.enable.DynamicMethodInvocation" value="false" />
<constant name="struts.devMode" value="true" />
<package name="uploadSnew" namespace="/" extends="struts-default">
<action name="clickupload" class="tryupload.UploadNewFile" method="execute">
<interceptor-ref name="basicStack"/>
<interceptor-ref name="fileUpload">
<param name="maximumSize">2048000</param>
<param name="allowedTypes">image/jpeg,image/gif</param >
</interceptor-ref>
<result name="success" >/success.jsp</result>
<result name="error">/error.jsp</result>
<result name="input">/index.jsp</result>
</action>
</package>
</struts>
当我上传文件并提交时，显示：
Struts Problem Report
Struts has detected an unhandled exception:
Messages:
File: java/io/File.java
Line number: 291
--------------------------------------------------------------------------------
踪迹
java.lang.NullPointerException
java.io.File.<init>(File.java:291)
tryupload.UploadNewFile.execute(UploadNewFile.java:32)
sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
java.lang.reflect.Method.invoke(Method.java:606)
ognl.OgnlRuntime.invokeMethod(OgnlRuntime.java:870)
ognl.OgnlRuntime.callAppropriateMethod(OgnlRuntime.java:1293)
ognl.ObjectMethodAccessor.callMethod(ObjectMethodAccessor.java:68)
com.opensymphony.xwork2.ognl.accessor.XWorkMethodAccessor.callMethodWithDebugInfo(XWorkMethodAccessor.java:117)
com.opensymphony.xwork2.ognl.accessor.XWorkMethodAccessor.callMethod(XWorkMethodAccessor.java:108)
ognl.OgnlRuntime.callMethod(OgnlRuntime.java:1369)
ognl.ASTMethod.getValueBody(ASTMethod.java:90)
ognl.SimpleNode.evaluateGetValueBody(SimpleNode.java:212)
ognl.SimpleNode.getValue(SimpleNode.java:258)
ognl.Ognl.getValue(Ognl.java:494)
ognl.Ognl.getValue(Ognl.java:458)
com.opensymphony.xwork2.ognl.OgnlUtil$2.execute(OgnlUtil.java:309)
com.opensymphony.xwork2.ognl.OgnlUtil.compileAndExecute(OgnlUtil.java:340)
com.opensymphony.xwork2.ognl.OgnlUtil.getValue(OgnlUtil.java:307)
com.opensymphony.xwork2.DefaultActionInvocation.invokeAction(DefaultActionInvocation.java:423)
com.opensymphony.xwork2.DefaultActionInvocation.invokeActionOnly(DefaultActionInvocation.java:287)
com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:250)
org.apache.struts2.interceptor.FileUploadInterceptor.intercept(FileUploadInterceptor.java:326)
com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:244)
org.apache.struts2.interceptor.DeprecationInterceptor.intercept(DeprecationInterceptor.java:41)
com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:244)
com.opensymphony.xwork2.interceptor.ConversionErrorInterceptor.intercept(ConversionErrorInterceptor.java:138)
com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:244)
com.opensymphony.xwork2.interceptor.ParametersInterceptor.doIntercept(ParametersInterceptor.java:229)
com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:98)
com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:244)
com.opensymphony.xwork2.interceptor.ParametersInterceptor.doIntercept(ParametersInterceptor.java:229)
com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:98)
com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:244)
org.apache.struts2.interceptor.MultiselectInterceptor.intercept(MultiselectInterceptor.java:73)
com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:244)
org.apache.struts2.interceptor.DateTextFieldInterceptor.intercept(DateTextFieldInterceptor.java:125)
com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:244)
org.apache.struts2.interceptor.CheckboxInterceptor.intercept(CheckboxInterceptor.java:91)
com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:244)
com.opensymphony.xwork2.interceptor.PrepareInterceptor.doIntercept(PrepareInterceptor.java:171)
com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:98)
com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:244)
org.apache.struts2.interceptor.ServletConfigInterceptor.intercept(ServletConfigInterceptor.java:164)
com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:244)
com.opensymphony.xwork2.interceptor.ExceptionMappingInterceptor.intercept(ExceptionMappingInterceptor.java:189)
com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:244)
org.apache.struts2.impl.StrutsActionProxy.execute(StrutsActionProxy.java:54)
org.apache.struts2.dispatcher.Dispatcher.serviceAction(Dispatcher.java:564)
org.apache.struts2.dispatcher.FilterDispatcher.doFilter(FilterDispatcher.java:434)
org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:239)
org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:219)
org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:106)
org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:502)
org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:142)
org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:79)
org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:617)
org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:88)
org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:518)
org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1091)
org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:668)
org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1527)
org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.run(NioEndpoint.java:1484)
java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
java.lang.Thread.run(Thread.java:724)
You are seeing this page because development mode is enabled. Development mode, or devMode, enables extra debugging behaviors and reports to assist developers. To disable this mode, set:
struts.devMode=false
in your WEB-INF/classes/struts.properties file.
My console:
Sep 30, 2015 10:16:29 PM org.apache.struts2.interceptor.FileUploadInterceptor warn
WARNING: Content-Type not allowed: myFile "FiveFingerDeathPunch.jpg" "upload_1a24317f_cf06_45b2_be8d_1b56d56eab1e_00000000.tmp" image/pjpeg
Server path:E:\.metadata\.plugins\org.eclipse.wst.server.core\tmp0\wtpwebapps\tryupload\
Filename:null
UploadNewFile - 我的动作类：
package tryupload;
import java.io.File;
import java.io.IOException;
import javax.servlet.http.HttpServletRequest;
import org.apache.commons.io.FileUtils;
import com.opensymphony.xwork2.ActionSupport;
import org.apache.struts2.interceptor.ServletRequestAware;
public class UploadNewFile extends ActionSupport implements ServletRequestAware {
/**
*
*/
private static final long serialVersionUID = 1L;
private HttpServletRequest servletRequest;
private File myFile;
private String myFileContentType;
private String myFileFileName;
public File getMyFile() {
return myFile;
}
public void setMyFile(File myFile) {
this.myFile = myFile;
}
public String getMyFileFileName() {
return myFileFileName;
}
public void setMyFileFileName(String myFileFileName) {
this.myFileFileName = myFileFileName;
}
public String getMyFileContentType() {
return myFileContentType;
}
public void setMyFileContentType(String myFileContentType) {
this.myFileContentType = myFileContentType;
}
public String execute() throws Exception {
/*File saveFilePath = new File("WebContent/images" +myFileFileName);
System.out.println("Filename:"+myFileFileName);
*/
try {
String filePath = servletRequest.getSession().getServletContext().getRealPath("/");
System.out.println("Server path:" + filePath);
System.out.println("Filename:"+myFileFileName);
File fileToCreate = new File(filePath, this.myFileFileName);
FileUtils.copyFile(this.myFile, fileToCreate);
}
catch (IOException ex) {
System.out.println("Couldn't save file: " + ex.getMessage());
ex.getStackTrace();
addActionError(ex.getMessage());
return ERROR;
}
return SUCCESS;
}
@Override
public void setServletRequest(HttpServletRequest servletRequest) {
// TODO Auto-generated method stub
this.servletRequest = servletRequest;
}
}
答案 0 :(得分：1)
要正确处理多部分请求，FileUpload Interceptor必须在之前运行其他拦截器，否则会搞乱。然后从
更改顺序<interceptor-ref name="basicStack"/>
<interceptor-ref name="fileUpload">
<param name="maximumSize">2048000</param>
<param name="allowedTypes">image/jpeg,image/gif</param >
</interceptor-ref>
到
<interceptor-ref name="fileUpload">
<param name="maximumSize">2048000</param>
<param name="allowedTypes">image/jpeg,image/gif</param >
</interceptor-ref>
<interceptor-ref name="basicStack"/>
足以让它发挥作用。 Read more