spring 4.0 注解数据验证2

在spring 4.0 注解数据验证1中有基本的数据验证方法。还是那个POJO：

package com.suyin.pojo;

import java.lang.reflect.Field;

import org.hibernate.validator.constraints.NotBlank;

public class People {

    private int id;

    @NotBlank
    private String name;

    private String address;

    private int age;

    public final int getId() {
        return id;
    }

    public final void setId(int id) {
        this.id = id;
    }

    public final String getName() {
        return name;
    }

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

    public final String getAddress() {
        return address;
    }

    public final void setAddress(String address) {
        this.address = address;
    }

    public final int getAge() {
        return age;
    }

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

    @Override
    public String toString() {
        return "People [id=" + id + ", name=" + name + ", address=" + address
                + ", age=" + age + "]";
    }

    public People set(String name, Object obj) {
        try {
            Field f = this.getClass().getDeclaredField(name);
            f.setAccessible(true);
            f.set(this, obj);
        } catch (NoSuchFieldException | SecurityException
                | IllegalArgumentException | IllegalAccessException e) {
            e.printStackTrace();
        }
        return this;
    }

}

有如下需求： 添加时要保证name不为空；修改时要保证name和address不为空。这怎么办？

spring4.0 提供了解决方案。先写两个标志接口 First和Second，类似于java.io.Serializable，如下：

package com.suyin.my.va;

public interface First {}

和

package com.suyin.my.va;

public interface Second {}

改造People如下：

package com.suyin.pojo;

import java.lang.reflect.Field;

import org.hibernate.validator.constraints.Email;
import org.hibernate.validator.constraints.NotBlank;

import com.suyin.my.va.First;
import com.suyin.my.va.Second;

public class People {

    private int id;

    @NotBlank(groups= {First.class,Second.class})
    private String name;

    @NotBlank(groups= {Second.class})
    private String address;

    private int age;

    public final int getId() {
        return id;
    }

    public final void setId(int id) {
        this.id = id;
    }

    public final String getName() {
        return name;
    }

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

    public final String getAddress() {
        return address;
    }

    public final void setAddress(String address) {
        this.address = address;
    }

    public final int getAge() {
        return age;
    }

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

    @Override
    public String toString() {
        return "People [id=" + id + ", name=" + name + ", address=" + address
                + ", age=" + age + "]";
    }

    public People set(String name, Object obj) {
        try {
            Field f = this.getClass().getDeclaredField(name);
            f.setAccessible(true);
            f.set(this, obj);
        } catch (NoSuchFieldException | SecurityException
                | IllegalArgumentException | IllegalAccessException e) {
            e.printStackTrace();
        }
        return this;
    }

}

在name上加了  @NotBlank(groups= {First.class,Second.class})

在address上加了 @NotBlank(groups= {Second.class})

可以猜测当遇到 First标志时会验证name，在遇到Second标志时会验证name和address。 那么现在只要告诉spring验证时使用First还是Second标志就可以了。

在Controller中有方法

    @RequestMapping(value="/add")
    public String add(@Validated(First.class) People p,BindingResult result, HttpServletRequest request) {
        if(result.hasErrors()) {
            System.out.println(result.getFieldErrors());
            return "error";
        }
        this.peopleService.add(p);
        return "people/detail";
    }    

    @RequestMapping("/update")
    public String update(@Validated(Second.class) People p,BindingResult result,HttpServletRequest request) {
        if(result.hasErrors()) {
            System.out.println(result.getFieldErrors());
            return "error";
        }
        this.peopleService.update(p);
        return "people/detail";
    }

在每个方法参数People p之前，把原来的@Valid改为了@Validated，并且分别加上了参数First.class和Second.class。