Available since Struts 6.4.0 as replacement forFile Upload Interceptor
Seethis page for more examples and advanced configuration.
Interceptor that is based off ofMultiPartRequestWrapper, which is automatically applied for any request that includes a file. If an action implementsorg.apache.struts2.action.UploadedFilesAware interface, the interceptor will passinformation and content of uploaded files using the callback methodwithUploadedFiles(List<UploadedFile>).
See the example code section.
This interceptor will add several field errors, assuming that the action implementsValidationAware. These error messages are based on several i18n values stored instruts-messages.properties, a default i18n file processed for all i18n requests. You can override the text of these messages by providing text for the following keys:
struts.messages.error.uploading - a general error that occurs when the file could not be uploadedstruts.messages.error.file.too.large - occurs when the uploaded file is too largestruts.messages.error.content.type.not.allowed - occurs when the uploaded file does not match the expected content types specifiedstruts.messages.error.file.extension.not.allowed - occurs when the uploaded file does not match the expected file extensions specifiedmaximumSize (optional) - the maximum size (in bytes) that the interceptor will allow a file reference to be seton the action. Note, this isnot related to the various properties found in struts.properties. Default to approximately 2MB.allowedTypes (optional) - a comma separated list of content types (ie:text/html) that the interceptor will allowa file reference to be set on the action. If none is specified allow all types to be uploaded.allowedExtensions (optional) - a comma separated list of file extensions (ie:.html) that the interceptor will allowa file reference to be set on the action. If none is specified allow all extensions to be uploaded.You can extend this interceptor and override the acceptFile method to provide more control over which files are supported and which are not.
Seethis page for more examples and advanced configuration.
Example action mapping:
<actionname="doUpload"class="com.example.UploadAction"><interceptor-refname="actionFileUpload"/><interceptor-refname="basicStack"/><resultname="success">good_result.jsp</result></action>Notice the interceptor configuration in the preceding example.
Example JSP form tags:
<s:formaction="doUpload"method="post"enctype="multipart/form-data"><s:filename="upload"label="File"/><s:submit/></s:form>You must set the encoding tomultipart/form-data in the form where the user selects the file to upload.
Example Action class:
publicclassUploadActionextendsActionSupportimplementsUploadedFilesAware{privateUploadedFileuploadedFile;privateStringcontentType;privateStringfileName;privateStringoriginalName;@OverridepublicvoidwithUploadedFiles(List<UploadedFile>uploadedFiles){if(!uploadedFiles.isEmpty()){this.uploadedFile=uploadedFiles.get(0);this.fileName=uploadedFile.getName();this.contentType=uploadedFile.getContentType();this.originalName=uploadedFile.getOriginalName();}}publicStringexecute(){//do something with the filereturnSUCCESS;}}Setting parameters example:
<interceptor-refname="actionFileUpload"><paramname="allowedTypes"> image/png,image/gif,image/jpeg</param></interceptor-ref>This part is optional and would be done in place of the<interceptor-ref name="actionFileUpload"/> line in the action mapping example above.