4-2 买家类目-dao（下）

查询出来的对象ProductCategory就已经有updateTime和createTime了，然而你只是把对象的categoryType给修改了一下，修改之后就执行save方法保存了。所以它还是原来的时间。如果有一个自动更新时间的目的，那就增加一个注解

@DynamicUpdate //动态更新时间.
public class ProductCategory{

package com.imooc.sell.dataobject;

//import javax.persistence.Table;


import org.hibernate.annotations.DynamicUpdate;
import org.hibernate.annotations.Proxy;

import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import java.util.Date;

/**
 * 类目
 * Created by zhongzh
 * 2018-05-20 9:31
 * s_product_category
 */
//@Table(name = "s_product_category")
@Entity//把数据库映射成对象
@Proxy(lazy = false)
@DynamicUpdate //动态更新时间.
public class ProductCategory{
     /** 类目id. */
     @Id//Id是主键,自增类型的。
     //@GeneratedValue//相当于调用了native策略
     //@GeneratedValue(strategy = GenerationType.AUTO)
     @GeneratedValue(strategy = GenerationType.IDENTITY)
     private Integer categoryId;//字段名的命名方式也是一样的，把下划线改成为空。
     /** 类目名字. */
     private String categoryName;

     /** 类目编号. */
     private Integer categoryType;
     /** 创建时间. */
     private Date createTime;
     /** 修改时间. */
     private Date updateTime;
    //不要忘了Getter和Setter方法
    public Integer getCategoryId() {
        return categoryId;
    }

    public void setCategoryId(Integer categoryId) {
        this.categoryId = categoryId;
    }

    public String getCategoryName() {
        return categoryName;
    }

    public void setCategoryName(String categoryName) {
        this.categoryName = categoryName;
    }

    public Integer getCategoryType() {
        return categoryType;
    }

    public void setCategoryType(Integer categoryType) {
        this.categoryType = categoryType;
    }

    public Date getCreateTime() {
        return createTime;
    }

    public void setCreateTime(Date createTime) {
        this.createTime = createTime;
    }

    public Date getUpdateTime() {
        return updateTime;
    }

    public void setUpdateTime(Date updateTime) {
        this.updateTime = updateTime;
    }

    @Override
    public String toString() {
        return "ProductCategory{" +
                "categoryId=" + categoryId +
                ", categoryName='" + categoryName + '\'' +
                ", categoryType=" + categoryType +
                '}';
    }
}

更新之前

Hibernate: select productcat0_.category_id as category1_0_0_, productcat0_.category_name as category2_0_0_, productcat0_.category_type as category3_0_0_, productcat0_.create_time as create_t4_0_0_, productcat0_.update_time as update_t5_0_0_ from product_category productcat0_ where productcat0_.category_id=?
Hibernate: select productcat0_.category_id as category1_0_0_, productcat0_.category_name as category2_0_0_, productcat0_.category_type as category3_0_0_, productcat0_.create_time as create_t4_0_0_, productcat0_.update_time as update_t5_0_0_ from product_category productcat0_ where productcat0_.category_id=?

更新之后

---

    @Test
    public void saveTest(){
        ProductCategory productCategory = repository.getOne(2);
        //ProductCategory productCategory = new ProductCategory();
        //productCategory.setCategoryId(2);
        //productCategory.setCategoryName("女生最爱");
        //productCategory.setCategoryType(3);
        //productCategory.setCategoryName("男生最爱");
        //productCategory.setCategoryType(4);
        //productCategory.setCategoryName("老少咸宜");
        //productCategory.setCategoryType(5);
        productCategory.setCategoryType(11);
        repository.save(productCategory);
    }

Hibernate: select productcat0_.category_id as category1_0_0_, productcat0_.category_name as category2_0_0_, productcat0_.category_type as category3_0_0_, productcat0_.create_time as create_t4_0_0_, productcat0_.update_time as update_t5_0_0_ from product_category productcat0_ where productcat0_.category_id=?
Hibernate: select productcat0_.category_id as category1_0_0_, productcat0_.category_name as category2_0_0_, productcat0_.category_type as category3_0_0_, productcat0_.create_time as create_t4_0_0_, productcat0_.update_time as update_t5_0_0_ from product_category productcat0_ where productcat0_.category_id=?
Hibernate: update product_category set category_type=? where category_id=?

更新之后

---

老司机带来干货了！！！！！

实体类对象不用再写getter和setter方法了。在pom.xml引进