我正在尝试使用 Struts 2 文件上传，但在我看来它不起作用。下面是我的代码。
UploadAction.java:
public class UploadAction extends ActionSupport{
private File file;
private String orgFileName;
private String orgContentType;
public void setUpload(File file){
this.file=file;
}
public void setUploadContentType(String contentType){
this.orgContentType=contentType;
}
public void setUploadFileName(String fileName){
this.orgFileName=fileName;
}
@Override
public String execute(){
if(file==null)
{
System.out.println("No file....");
}
System.out.println(orgContentType);
System.out.println(orgFileName);
return SUCCESS;
}
}
struts.xml:
<constant name="struts.multipart.maxSize" value="20971520" />
<constant name="struts2.multipart.saveDir" value="C:/users/sabertooth/desktop/upload" />
<include file="example.xml"/>
<!-- Configuration for the default package. -->
<package name="default" extends="struts-default">
<action name="upload" class="UploadAction">
<result name="success">/example/HelloWorld.jsp</result>
</action>
</package>
我也在尝试设置 struts2.multipart.saveDir 属性，正如您在上面看到的那样，但是当我读取服务器日志时，我看到了这一行
unable to find `struts.multipart.saveDir` defaulting to `javax.servlet.dir`
此外，文件对象为空，因为没有文件...在控制台上打印出来。 我不知道这里出了什么问题。
编辑:
fileupload.jsp:
<%@page contentType="text/html" pageEncoding="UTF-8"%>
<%@ taglib prefix="s" uri="/struts-tags" %>
<!DOCTYPE html>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>JSP Page</title>
</head>
<body>
<h1>upload file below</h1>
<s:form action="upload" method="post" enctype="multipart/form-data">
<input type="file" name="file" id="uploadfile" />
<input type="submit" id="submit" />
</s:form>
</body>
</html>
最佳答案
除了更改 saveDir(确实没有必要，而且很危险)，您没有遵循 Action 类中的约定:私有(private)变量的名称必须与其 Getters 和 Setters 的名称相匹配;最后，在页面中，您通过指向私有(private)变量而不是 setter 来匹配名称。将其更改为:
public class UploadAction extends ActionSupport{
private File upload;
private String uploadFileName;
private String uploadContentType;
public void setUpload(File upload){
this.upload=upload;
}
public void setUploadContentType(String uploadContentType){
this.uploadContentType=uploadContentType;
}
public void setUploadFileName(String uploadFileName){
this.uploadFileName=uploadFileName;
}
@Override
public String execute(){
if(upload==null)
{
System.out.println("No file....");
}
System.out.println(uploadContentType);
System.out.println(uploadFileName);
return SUCCESS;
}
}
JSP
<s:form action="upload" method="post" enctype="multipart/form-data">
<input type="file" name="upload" id="uploadfile" />
<input type="submit" id="submit" />
</s:form>
关于java - Struts 2 文件上传 : File object being null，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/20733554/