在Struts2中为我们提供了比较简单的文件上传方式.
首先引入commons-fileupload-x.jar、commons-io-x.jar 这两个jar包,然后引入Struts2相关jar包
接下来新建一个jsp文件:写一个文件上传表单,这里需要特别注意要在form加上enctype="multipart/form-data" method="post" .
<form action="/admin/center/brandAction!addBrandProcess" enctype="multipart/form-data" method="post"> <table width="90%" border="0" cellspacing="2" cellpadding="3" align="center"> <tr bgcolor="f5f5f5"> <td width="22%"> <div align="right">图片:</div> </td> <td width="78%"><input type="file" name="uploadFile" /> </td> </tr> <tr bgcolor="f5f5f5"> <td colspan="2"> <div align="center"> <input type="submit" value=" 确 定 "> </div> </td> </tr> </table> </form>
下一步:添加我们的Action类:
package gd.hz.shopping.action; import java.io.File; import java.io.IOException; import java.text.SimpleDateFormat; import java.util.Date; import java.util.UUID; import org.apache.commons.io.FileUtils; import org.apache.struts2.ServletActionContext; import org.springframework.context.annotation.Scope; import org.springframework.stereotype.Controller; import com.opensymphony.xwork2.ActionSupport; @Controller("brandAction") @Scope("prototype") public class Test extends ActionSupport { private static final long serialVersionUID = 1L; //此属性对应于表单中文件字段的名称 private File uploadFile; //下面的这两个属性的命名必须遵守上定的规则,即为"表单中文件字段的名称" + "相应的后缀" private String uploadFileContentType; // 得到上传的文件的数据类型, private String uploadFileFileName; // 得到上传的文件的名称 public File getUploadFile() { return uploadFile; } public void setUploadFile(File uploadFile) { this.uploadFile = uploadFile; } public String getUploadFileContentType() { return uploadFileContentType; } public void setUploadFileContentType(String uploadFileContentType) { this.uploadFileContentType = uploadFileContentType; } public String getUploadFileFileName() { return uploadFileFileName; } public void setUploadFileFileName(String uploadFileFileName) { this.uploadFileFileName = uploadFileFileName; } public String addBrandProcess() throws IOException { String realPath = ServletActionContext.getServletContext().getRealPath("/images"); SimpleDateFormat date = new SimpleDateFormat("/yyyy/MM/dd"); String dateTime = date.format(new Date()); realPath += dateTime; uploadFileFileName = UUID.randomUUID().toString() + uploadFileFileName.substring(uploadFileFileName.lastIndexOf('.')); System.out.println(uploadFileContentType); //控制图片类型 if(uploadFileContentType.equals("image/gif") || uploadFileContentType.equals("image/jpeg") || uploadFileContentType.equals("image/png") || uploadFileContentType.equals("image/bmp") || uploadFileContentType.equals("image/x-icon") || uploadFileContentType.equals("image/pjpeg")) { //判断文件是否为空,并且文件不能大于2M if(uploadFile != null && uploadFile.length() < 2097152) { //根据 parent 抽象路径名和 child 路径名字符串创建一个新 File 实例。 File filePath = new File(new File(realPath), uploadFileFileName); //判断路径是否存在 if(!filePath.getParentFile().exists()) { //如果不存在,则递归创建此路径 filePath.getParentFile().mkdirs(); } System.out.println(uploadFileFileName); System.out.println(filePath.getParentFile()); //将文件保存到硬盘上,Struts2会帮我们自动删除临时文件 try { FileUtils.copyFile(uploadFile, filePath); } catch (IOException e) { System.out.println("图片上传失败"); e.printStackTrace(); } } } return "success"; } }
上面还是要遵守约定大于配置,注意名称的命名,uploadFileContentType和uploadFileFileName必须遵守Struts2的规则.
Struts2默认文件的上传大小是2M,当大于2M时会抛出异常,这里我们可以在struts.xml文件里做如下配置,控制上传文件的大小:<struts> <constant name="struts.multipart.maxSize" value="10485761"/> </struts>