在Struts2中,上传文件时,只要使用java.io.File类来描述上传文件即可,比直接使用Commons-FileUpload组件要简单的多。
上传单个文件:
如果上传的是单个文件,则在Action类中定义一个File类型的变量。该变量的名字与JSP页面上的标签的name属性相对应,只有这样Struts2才能使客户端上传的文件自动与Action类中的相应的属性进行关联处理。
上传多个文件:
如果上传的是多个文件,这时在JSP页面中的所有的标签的name属性值都必须相同,这时Action中相对应的属性就要使用List或File[]用来表示多个文件的信息。
保存文件相关属性的变量设置如下:
private List
private List
private List
以下是一个使用Struts 2上传多个文件的例子,把上传的文件重新用生成的随机数命名:
Struts2上传文件相关代码
public class UploadFilesAction extends ActionSupport {
private List upload;
private List uploadContentType;
private List uploadFileName;
private String uploadPath;
private String result;
private boolean success;
private String msg;
public boolean isSuccess() {
return success;
}
public String getMsg() {
return msg;
}
public String getResult() {
return result;
}
public void setUpload(List upload) {
this.upload = upload;
}
public void setUploadContentType(List uploadContentType) {
this.uploadContentType = uploadContentType;
}
public void setUploadFileName(List uploadFileName) {
this.uploadFileName = uploadFileName;
}
public void setUploadPath(String uploadPath) {
this.uploadPath = uploadPath;
}
public String execute() throws Exception {
for (int i = 0; i < uploadFileName.size(); i++) {
Random random = new Random();
String filename = uploadFileName.get(i);
//把上传的文件用生成的随机数重新命名
//并判断生成的文件名是否已经存在
//如果存在,则继续生成随机数命名,直到找打还没使用的随机数为止
filename = uploadPath + random.nextLong()
\+ filename.substring(filename.lastIndexOf("."));
while (new File(filename).exists()) {
filename = uploadPath + random.nextLong()
\+ filename.substring(filename.lastIndexOf("."));
}
FileOutputStream fos = new FileOutputStream(filename);
InputStream is = new FileInputStream(upload.get(i));
byte[] buffer = new byte[8192];
int count = 0;
while ((count = is.read(buffer)) > 0) {
fos.write(buffer, 0, count);
}
fos.close();
is.close();
}
success=true;
msg = "文件上传成功!";
return "result";
}
}
在struts.xml文件中可做如下配置: