剛開始學Struts2，下午參照黑弓老師的視頻寫一個簡單的
文件上傳
模塊，結果弄了一下午，File，FileName和ContentType全為null，實在搞不懂了，大家幫我看看，謝謝了！！
先貼代碼：
Fileupload.jsp代碼
<%@ page language="java" contentType="text/html; charset=UTF-8"?
??? pageEncoding="UTF-8"%>?
<%@taglib prefix="s" uri="/struts-tags" %>?
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">?
<html>?
<head>?
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">?
<title><s:text name="loginPage" /></title>?
</head>?
<body>?
??? <s:form action="fileUpload" method="post" enctype="multipart/form-data">?
??????? 選擇文件：?
??????? <s:file name="upload"></s:file>?
??????? <s:submit></s:submit>?
??? </s:form>?
</body>?
</html>?
----------------------------
Uploadaction.java代碼
public class UploadAction extends ActionSupport {?
?
??? private File upload;?
??? private String uploadContentType;?
??? private String uploadFileName;?
?
??? public File getUpload() {?
??????? return upload;?
??? }?
?
??? public void setUpload(File upload) {?
??????? this.upload = upload;?
??? }?
?
??? public String getUploadContentType() {?
??????? return uploadContentType;?
??? }?
?
??? public void setUploadContentType(String uploadContentType) {?
??????? this.uploadContentType = uploadContentType;?
??? }?
?
??? public String getUploadFileName() {?
??????? return uploadFileName;?
??? }?
?
?
??? public void setUploadFileName(String uploadFileName) {?
??????? this.uploadFileName = uploadFileName;?
??? }?
?
??? public String execute() throws Exception {?
??????? System.out.println(uploadContentType + " : " + uploadFileName + "\n");?
??????? FileInputStream fis = new FileInputStream(upload);?
??????? FileOutputStream fos = new FileOutputStream("D:/" + uploadFileName);?
??????? byte[] buffer = new byte[1024];?
??????? int length = 0;?
??????? while((length = fis.read(buffer)) != -1) {?
??????????? fos.write(buffer, 0, length);?
??????? }?
??????? fis.close();?
??????? fos.close();?
??????? return null;?
??? }?
}?
------------------------
Struts.xml代碼
<?xml version="1.0" encoding="UTF-8" ?>?
<!DOCTYPE struts PUBLIC?
??? "-//Apache Software Foundation//DTD Struts Configuration 2.3//EN"?
??? "struts-2.3.dtd">?
<struts>?
??? <constant name="struts.devMode" value="true"></constant>?
??? <constant name="struts.configuration.xml.reload" value="true"></constant>?
??? <constant name="struts.custom.i18n.resources" value="mess"></constant>?
??? <constant name="struts.i18n.encoding" value="UTF-8"></constant>?
??? <constant name="struts.multipart.saveDir" value="/tmp"></constant>?
?
??? <package name="lee" extends="struts-default">?
??????? <action name="fileUpload" class="com.tt.www.action.UploadAction">?
??????????? <result name="input">/fileUpload.jsp</result>?
??????? </action>?
??????? <action name="login" class="com.tt.www.action.LoginAction">?
??????????? <result name="input">/login.jsp</result>?
??????????? <result name="success">/success.jsp</result>?
??????????? <result name="error">/error.jsp</result>?
??????? </action>?
??? </package>?
</struts>?
----------------------
導入的Jar包有：
-----------------------
錯誤提示為：
Struts Problem Report
Struts has detected an unhandled exception:
Messages:
File: java/io/FileInputStream.java
Line number: 103
Stacktraces
java.lang.NullPointerException
??? java.io.FileInputStream.(FileInputStream.java:103)
??? com.abchina.www.action.UploadAction.execute(UploadAction.java:19)
??? sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
??? sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
??? sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
??? java.lang.reflect.Method.invoke(Method.java:597)
??? com.opensymphony.xwork2.DefaultActionInvocation.invokeAction(DefaultActionInvocation.java:453)
??? com.opensymphony.xwork2.DefaultActionInvocation.invokeActionOnly(DefaultActionInvocation.java:292)
??? com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:255)
??? org.apache.struts2.interceptor.debugging.DebuggingInterceptor.intercept(DebuggingInterceptor.java:256)
??? com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:249)
??? 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:249)
??? com.opensymphony.xwork2.validator.ValidationInterceptor.doIntercept(ValidationInterceptor.java:265)
??? 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:249)
??? com.opensymphony.xwork2.interceptor.ConversionErrorInterceptor.intercept(ConversionErrorInterceptor.java:138)
??? com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:249)
??? com.opensymphony.xwork2.interceptor.ParametersInterceptor.doIntercept(ParametersInterceptor.java:211)
??? com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:98)
??? com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:249)
??? com.opensymphony.xwork2.interceptor.ParametersInterceptor.doIntercept(ParametersInterceptor.java:211)
??? com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:98)
??? com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:249)
??? com.opensymphony.xwork2.interceptor.StaticParametersInterceptor.intercept(StaticParametersInterceptor.java:190)
??? com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:249)
??? org.apache.struts2.interceptor.MultiselectInterceptor.intercept(MultiselectInterceptor.java:75)
??? com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:249)
??? org.apache.struts2.interceptor.CheckboxInterceptor.intercept(CheckboxInterceptor.java:90)
??? com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:249)
??? org.apache.struts2.interceptor.FileUploadInterceptor.intercept(FileUploadInterceptor.java:320)
??? com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:249)
??? com.opensymphony.xwork2.interceptor.ModelDrivenInterceptor.intercept(ModelDrivenInterceptor.java:100)
??? com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:249)
??? com.opensymphony.xwork2.interceptor.ScopedModelDrivenInterceptor.intercept(ScopedModelDrivenInterceptor.java:141)
??? com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:249)
??? com.opensymphony.xwork2.interceptor.ChainingInterceptor.intercept(ChainingInterceptor.java:145)
??? com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:249)
??? 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:249)
??? com.opensymphony.xwork2.interceptor.I18nInterceptor.intercept(I18nInterceptor.java:176)
??? com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:249)
??? org.apache.struts2.interceptor.ServletConfigInterceptor.intercept(ServletConfigInterceptor.java:164)
??? com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:249)
??? com.opensymphony.xwork2.interceptor.AliasInterceptor.intercept(AliasInterceptor.java:192)
??? com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:249)
??? com.opensymphony.xwork2.interceptor.ExceptionMappingInterceptor.intercept(ExceptionMappingInterceptor.java:187)
??? com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:249)
??? org.apache.struts2.impl.StrutsActionProxy.execute(StrutsActionProxy.java:54)
??? org.apache.struts2.dispatcher.Dispatcher.serviceAction(Dispatcher.java:511)
??? org.apache.struts2.dispatcher.ng.ExecuteOperations.executeAction(ExecuteOperations.java:77)
??? org.apache.struts2.dispatcher.ng.filter.StrutsPrepareAndExecuteFilter.doFilter(StrutsPrepareAndExecuteFilter.java:91)
??? org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243)
??? org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
??? org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:225)
??? org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:169)
??? org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:472)
??? org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:168)
??? org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:98)
??? org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:927)
??? org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118)
??? org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:407)
??? org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:999)
??? org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:565)
??? org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:307)
??? java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886)
??? java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908)
??? java.lang.Thread.run(Thread.java:619)
先貼代碼：
Fileupload.jsp代碼
<%@ page language="java" contentType="text/html; charset=UTF-8"?
??? pageEncoding="UTF-8"%>?
<%@taglib prefix="s" uri="/struts-tags" %>?
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">?
<html>?
<head>?
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">?
<title><s:text name="loginPage" /></title>?
</head>?
<body>?
??? <s:form action="fileUpload" method="post" enctype="multipart/form-data">?
??????? 選擇文件：?
??????? <s:file name="upload"></s:file>?
??????? <s:submit></s:submit>?
??? </s:form>?
</body>?
</html>?
----------------------------
Uploadaction.java代碼
public class UploadAction extends ActionSupport {?
?
??? private File upload;?
??? private String uploadContentType;?
??? private String uploadFileName;?
?
??? public File getUpload() {?
??????? return upload;?
??? }?
?
??? public void setUpload(File upload) {?
??????? this.upload = upload;?
??? }?
?
??? public String getUploadContentType() {?
??????? return uploadContentType;?
??? }?
?
??? public void setUploadContentType(String uploadContentType) {?
??????? this.uploadContentType = uploadContentType;?
??? }?
?
??? public String getUploadFileName() {?
??????? return uploadFileName;?
??? }?
?
?
??? public void setUploadFileName(String uploadFileName) {?
??????? this.uploadFileName = uploadFileName;?
??? }?
?
??? public String execute() throws Exception {?
??????? System.out.println(uploadContentType + " : " + uploadFileName + "\n");?
??????? FileInputStream fis = new FileInputStream(upload);?
??????? FileOutputStream fos = new FileOutputStream("D:/" + uploadFileName);?
??????? byte[] buffer = new byte[1024];?
??????? int length = 0;?
??????? while((length = fis.read(buffer)) != -1) {?
??????????? fos.write(buffer, 0, length);?
??????? }?
??????? fis.close();?
??????? fos.close();?
??????? return null;?
??? }?
}?
------------------------
Struts.xml代碼
<?xml version="1.0" encoding="UTF-8" ?>?
<!DOCTYPE struts PUBLIC?
??? "-//Apache Software Foundation//DTD Struts Configuration 2.3//EN"?
??? "struts-2.3.dtd">?
<struts>?
??? <constant name="struts.devMode" value="true"></constant>?
??? <constant name="struts.configuration.xml.reload" value="true"></constant>?
??? <constant name="struts.custom.i18n.resources" value="mess"></constant>?
??? <constant name="struts.i18n.encoding" value="UTF-8"></constant>?
??? <constant name="struts.multipart.saveDir" value="/tmp"></constant>?
?
??? <package name="lee" extends="struts-default">?
??????? <action name="fileUpload" class="com.tt.www.action.UploadAction">?
??????????? <result name="input">/fileUpload.jsp</result>?
??????? </action>?
??????? <action name="login" class="com.tt.www.action.LoginAction">?
??????????? <result name="input">/login.jsp</result>?
??????????? <result name="success">/success.jsp</result>?
??????????? <result name="error">/error.jsp</result>?
??????? </action>?
??? </package>?
</struts>?
----------------------
導入的Jar包有：
-----------------------
錯誤提示為：
Struts Problem Report
Struts has detected an unhandled exception:
Messages:
File: java/io/FileInputStream.java
Line number: 103
Stacktraces
java.lang.NullPointerException
??? java.io.FileInputStream.(FileInputStream.java:103)
??? com.abchina.www.action.UploadAction.execute(UploadAction.java:19)
??? sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
??? sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
??? sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
??? java.lang.reflect.Method.invoke(Method.java:597)
??? com.opensymphony.xwork2.DefaultActionInvocation.invokeAction(DefaultActionInvocation.java:453)
??? com.opensymphony.xwork2.DefaultActionInvocation.invokeActionOnly(DefaultActionInvocation.java:292)
??? com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:255)
??? org.apache.struts2.interceptor.debugging.DebuggingInterceptor.intercept(DebuggingInterceptor.java:256)
??? com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:249)
??? 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:249)
??? com.opensymphony.xwork2.validator.ValidationInterceptor.doIntercept(ValidationInterceptor.java:265)
??? 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:249)
??? com.opensymphony.xwork2.interceptor.ConversionErrorInterceptor.intercept(ConversionErrorInterceptor.java:138)
??? com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:249)
??? com.opensymphony.xwork2.interceptor.ParametersInterceptor.doIntercept(ParametersInterceptor.java:211)
??? com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:98)
??? com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:249)
??? com.opensymphony.xwork2.interceptor.ParametersInterceptor.doIntercept(ParametersInterceptor.java:211)
??? com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:98)
??? com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:249)
??? com.opensymphony.xwork2.interceptor.StaticParametersInterceptor.intercept(StaticParametersInterceptor.java:190)
??? com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:249)
??? org.apache.struts2.interceptor.MultiselectInterceptor.intercept(MultiselectInterceptor.java:75)
??? com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:249)
??? org.apache.struts2.interceptor.CheckboxInterceptor.intercept(CheckboxInterceptor.java:90)
??? com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:249)
??? org.apache.struts2.interceptor.FileUploadInterceptor.intercept(FileUploadInterceptor.java:320)
??? com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:249)
??? com.opensymphony.xwork2.interceptor.ModelDrivenInterceptor.intercept(ModelDrivenInterceptor.java:100)
??? com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:249)
??? com.opensymphony.xwork2.interceptor.ScopedModelDrivenInterceptor.intercept(ScopedModelDrivenInterceptor.java:141)
??? com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:249)
??? com.opensymphony.xwork2.interceptor.ChainingInterceptor.intercept(ChainingInterceptor.java:145)
??? com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:249)
??? 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:249)
??? com.opensymphony.xwork2.interceptor.I18nInterceptor.intercept(I18nInterceptor.java:176)
??? com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:249)
??? org.apache.struts2.interceptor.ServletConfigInterceptor.intercept(ServletConfigInterceptor.java:164)
??? com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:249)
??? com.opensymphony.xwork2.interceptor.AliasInterceptor.intercept(AliasInterceptor.java:192)
??? com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:249)
??? com.opensymphony.xwork2.interceptor.ExceptionMappingInterceptor.intercept(ExceptionMappingInterceptor.java:187)
??? com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:249)
??? org.apache.struts2.impl.StrutsActionProxy.execute(StrutsActionProxy.java:54)
??? org.apache.struts2.dispatcher.Dispatcher.serviceAction(Dispatcher.java:511)
??? org.apache.struts2.dispatcher.ng.ExecuteOperations.executeAction(ExecuteOperations.java:77)
??? org.apache.struts2.dispatcher.ng.filter.StrutsPrepareAndExecuteFilter.doFilter(StrutsPrepareAndExecuteFilter.java:91)
??? org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243)
??? org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
??? org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:225)
??? org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:169)
??? org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:472)
??? org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:168)
??? org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:98)
??? org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:927)
??? org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118)
??? org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:407)
??? org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:999)
??? org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:565)
??? org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:307)
??? java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886)
??? java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908)
??? java.lang.Thread.run(Thread.java:619)
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