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File Upload Interceptor

See this page for more examples and advanced configuration

Interceptor that is based off of {@link MultiPartRequestWrapper}, which is automatically applied for any request that includes a file. It adds the following parameters, where [File Name] is the name given to the file uploaded by the HTML form:

You can get access to these files by merely providing setters in your action that correspond to any of the three patterns above, such as setDocument(File document), setDocumentContentType(String contentType), etc.
See the example code section.

This interceptor will add several field errors, assuming that the action implements {@link ValidationAware}. These error messages are based on several i18n values stored in, a default i18n file processed for all i18n requests. You can override the text of these messages by providing text for the following keys:


Extending the Interceptor

You can extend this interceptor and override the acceptFile method to provide more control over which files are supported and which are not.


Example action mapping:

 <action name="doUpload" class="com.example.UploadAction">
     <interceptor-ref name="fileUpload"/>
     <interceptor-ref name="basicStack"/>
     <result name="success">good_result.jsp</result>

Notice the interceptor configuration in the preceding example.

Example JSP form tags:

   <s:form action="doUpload" method="post" enctype="multipart/form-data">
       <s:file name="upload" label="File"/>

You must set the encoding to multipart/form-data in the form where the user selects the file to upload.

Example Action class:

    package com.example;

    import com.opensymphony.xwork2.ActionSupport;

    public UploadAction extends ActionSupport {
       private File file;
       private String contentType;
       private String filename;

       public void setUpload(File file) {
          this.file = file;

       public void setUploadContentType(String contentType) {
          this.contentType = contentType;

       public void setUploadFileName(String filename) {
          this.filename = filename;

       public String execute() {
          return SUCCESS;

Setting parameters example:

<interceptor-ref name="fileUpload">
  <param name="allowedTypes">

This part is optional and would be done in place of the

<interceptor-ref name="fileUpload"/>

line in the action mapping example above.