详解SpringBoot构建的Web项目如何在服务端校验表单输入

<?xml version="1.0" encoding="UTF-8"?>

  4.0.0

  org.example
  validating-form-input
  1.0-SNAPSHOT

  
    org.springframework.boot
    spring-boot-starter-parent
    1.5.1.RELEASE
  

  
    1.8
  

  
    
      
        org.springframework.boot
        spring-boot-maven-plugin
      
    
  

  
    
    
      org.springframework.boot
      spring-boot-starter-thymeleaf
    

    
    
      org.hibernate
      hibernate-validator
    

    
    
      org.apache.tomcat.embed
      tomcat-embed-el
    

    
    
      org.springframework.boot
      spring-boot-starter-test
      test
    
  

package hello;

import javax.validation.constraints.Min;
import javax.validation.constraints.NotNull;
import javax.validation.constraints.Size;

/**
 * Created by IntelliJ IDEA.
 * User: duqi
 * Date: 2017/2/28
 * Time: 21:53
 */
public class PersonForm {

  @NotNull
  @Size(min = 2, max = 30)
  private String name;

  @NotNull
  @Min(18)
  private Integer age;

  public String getName() {
    return name;
  }

  public Integer getAge() {
    return age;
  }

  public void setName(String name) {
    this.name = name;
  }

  public void setAge(Integer age) {
    this.age = age;
  }

  public String toString() {
    return "Person(Name: " + this.name + ", Age: " + this.age + ")";
  }
}

package hello;

import org.springframework.stereotype.Controller;
import org.springframework.validation.BindingResult;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.servlet.config.annotation.ViewControllerRegistry;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurerAdapter;

import javax.validation.Valid;

/**
 * Created by IntelliJ IDEA.
 * User: duqi
 * Date: 2017/3/2
 * Time: 14:07
 */
@Controller
public class WebController extends WebMvcConfigurerAdapter {

  @Override
  public void addViewControllers(ViewControllerRegistry registry) {
    registry.addViewController("/results").setViewName("results");
  }

  @GetMapping("/")
  public String showForm(PersonForm personForm) {
    return "form";
  }

  @PostMapping("/")
  public String checkPersonInfo(@Valid PersonForm personForm, BindingResult bindingResult) {
    if (bindingResult.hasErrors()) {
      return "form";
    }

    return "redirect:/results";
  }
}

  
  


  

    

      

        
Name:
        

        
Name Error
      
      

        
Age:
        

        
Age Error
      
      

        
Submit
      
    
  

  
  


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package hello;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;

/**
 * Created by IntelliJ IDEA.
 * User: duqi
 * Date: 2017/3/2
 * Time: 15:50
 */
@SpringBootApplication
public class Application {

  public static void main(String[] args) {
    SpringApplication.run(Application.class, args);
  }
}