spring的Vlidator注解

例如：

package com.aaa.maven.entity;

import org.hibernate.validator.constraints.NotBlank;

import javax.validation.constraints.Pattern;
import javax.validation.constraints.Size;
import java.util.Date;

public class Book {
    private Integer id;
    @NotBlank(message = "用户名不能为空")
    private String bname;

    @Pattern(regexp = "^([0-9]){1,5}$",message = "必须是数字",flags = Pattern.Flag.CASE_INSENSITIVE)
    private String price;

    @NotBlank
    @Size(min = 4,max = 20,message = "请输入4-20之间的字符串")
    private String publish;
    private Date   bdate;

    public Integer getId() {
        return id;
    }

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

    public String getBname() {
        return bname;
    }

    public void setBname(String bname) {
        this.bname = bname;
    }


    public String getPrice() {
        return price;
    }

    public void setPrice(String price) {
        this.price = price;
    }

    public String getPublish() {
        return publish;
    }

    public void setPublish(String publish) {
        this.publish = publish;
    }

    public Date getBdate() {
        return bdate;
    }

    public void setBdate(Date bdate) {
        this.bdate = bdate;
    }

}