【Struts 2】文件上传

前台页面：

请选择要上传的文件：<s:form action="UploadAction" method="post" enctype="multipart/form-data"><s:textfield name="username" label="上传人："></s:textfield><s:file name="file"></s:file><s:submit value="上传"></s:submit></s:form>

UploadAction：

public class UploadAction extends ActionSupport {private String username;private String fileName;private File file;private String fileContentType;public String getUsername() {return username;}public void setUsername(String username) {this.username = username;}public String getFileName() {return fileName;}public void setFileName(String fileName) {this.fileName = fileName;}public File getFile() {return file;}public void setFile(File file) {this.file = file;}public String getFileContentType() {return fileContentType;}public void setFileContentType(String fileContentType) {this.fileContentType = fileContentType;}public String execute() throws Exception {fileName=file.getName();String savepath=ServletActionContext.getRequest().getRealPath("/upload");InputStream is=new FileInputStream(file);File destFile=new File(savepath,fileName);OutputStream os=new FileOutputStream(destFile);byte[] buffer=new byte[400];int length=0;while((length=is.read(buffer))!=-1){os.write(buffer,0,length);}is.close();os.close();return SUCCESS;}}

结果页面：

上传成功！<br>上传人：<s:property value="username"/><br>文件名：<s:property value="fileName"/><br>文件类型：<s:property value="fileContentType"/>

Struts2在上传时，先将文件保存到默认的临时目录中，然后再服务器端将临时文件写入到服务器端目录中，
效果：