我有一个jsf表单,其中包含用户的电子邮件地址,简要说明和图像。当file == null时,完全忽略下面的else语句。如果没有上传图片,我想要告诉用户他们必须上传图片时出错。我该如何做到这一点?
import org.primefaces.model.UploadedFile;
private UploadedFile file;
public UploadedFile getFile() {
return file;
}
public void setFile(UploadedFile file) {
this.file = file;
}
public String upload() {
if (file!=null ) {
try {
System.out.println(file.getFileName());
InputStream fin2 = file.getInputstream();
Connection con = DataConnect.getConnection();
PreparedStatement pre = con.prepareStatement("insert into PICTURE_TABLE (EMAIL_ADDRESS,PRICE,ITEM_DESC,PICTURES,DATE) values(?,?,?,?,?)");
pre.setString(1, email);
pre.setString(2, price);
pre.setString(3,itemDesc);
pre.setBinaryStream(4, fin2, file.getSize());
pre.setString(5,time);
pre.executeUpdate();
System.out.println("Inserting Successfully!");
}
catch (Exception e) {
System.out.println("Exception-File Upload." + e.getMessage());
return "imageFail";
}
}
else{
FacesMessage msg = new FacesMessage("Please select image!!");
FacesContext.getCurrentInstance().addMessage(null, msg);
}
这是我正在使用的jsf标签。
<h:form enctype="multipart/form-data"