📅  最后修改于: 2020-11-11 06:27:20             🧑  作者: Mango
以下示例显示了如何使用Spring Web MVC Framework在表单中使用错误处理和验证器。首先,让我们拥有一个运行良好的Eclipse IDE,并考虑以下步骤,以使用Spring Web Framework开发基于动态表单的Web应用程序。
Step | Description |
---|---|
1 | Create a project with a name HelloWeb under a package com.tutorialspoint as explained in the Spring MVC – Hello World chapter. |
2 | Create Java classes Student, StudentController and StudentValidator under the com.tutorialspoint package. |
3 | Create view files addStudent.jsp, result.jsp under the jsp sub-folder. |
4 | The final step is to create the content of the source and configuration files and export the application as explained below. |
package com.tutorialspoint;
public class Student {
private Integer age;
private String name;
private Integer id;
public void setAge(Integer age) {
this.age = age;
}
public Integer getAge() {
return age;
}
public void setName(String name) {
this.name = name;
}
public String getName() {
return name;
}
public void setId(Integer id) {
this.id = id;
}
public Integer getId() {
return id;
}
}
package com.tutorialspoint;
import org.springframework.validation.Errors;
import org.springframework.validation.ValidationUtils;
import org.springframework.validation.Validator;
public class StudentValidator implements Validator {
@Override
public boolean supports(Class> clazz) {
return Student.class.isAssignableFrom(clazz);
}
@Override
public void validate(Object target, Errors errors) {
ValidationUtils.rejectIfEmptyOrWhitespace(errors,
"name", "required.name","Field name is required.");
}
}
package com.tutorialspoint;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Qualifier;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.validation.BindingResult;
import org.springframework.validation.Validator;
import org.springframework.validation.annotation.Validated;
import org.springframework.web.bind.WebDataBinder;
import org.springframework.web.bind.annotation.InitBinder;
import org.springframework.web.bind.annotation.ModelAttribute;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.servlet.ModelAndView;
@Controller
public class StudentController {
@Autowired
@Qualifier("studentValidator")
private Validator validator;
@InitBinder
private void initBinder(WebDataBinder binder) {
binder.setValidator(validator);
}
@RequestMapping(value = "/addStudent", method = RequestMethod.GET)
public ModelAndView student() {
return new ModelAndView("addStudent", "command", new Student());
}
@ModelAttribute("student")
public Student createStudentModel() {
return new Student();
}
@RequestMapping(value = "/addStudent", method = RequestMethod.POST)
public String addStudent(@ModelAttribute("student") @Validated Student student,
BindingResult bindingResult, Model model) {
if (bindingResult.hasErrors()) {
return "addStudent";
}
model.addAttribute("name", student.getName());
model.addAttribute("age", student.getAge());
model.addAttribute("id", student.getId());
return "result";
}
}
在这里,对于第一个服务方法student() ,我们在ModelAndView对象中传递了一个名称为“ command”的空白Studentobject,因为如果您使用的是