[SSM Distributed Architecture E-commerce Project-04] Use Spring4's generic injection to encapsulate BaseService

Almost every service requires the following methods:

1、 queryById
2、 queryAll
3、 queryOne
4、 queryListByWhere
5、 queryPageListByWhere
6、 save
7、 update
8、 deleteById
9、 deleteByIds
10、deleteByWhere

When encapsulating BaseService, you will encounter the following problems:
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So we can do it this way:
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package com.taotao.manage.service;

import java.util.Date;
import java.util.List;

import org.springframework.beans.factory.annotation.Autowired;

import com.github.abel533.entity.Example;
import com.github.abel533.mapper.Mapper;
import com.github.pagehelper.PageHelper;
import com.github.pagehelper.PageInfo;
import com.taotao.manage.pojo.BasePojo;

public abstract class BaseService<T extends BasePojo> {

    //@Autowired
    //private Mapper<T> mapper;

    public abstract Mapper<T> getMapper();

    /**
     * 根据id查询数据
     * 
     * @param id
     * @return
     */
    public T queryById(Long id) {
        return this.getMapper().selectByPrimaryKey(id);
    }

    /**
     * 查询所有数据
     * 
     * @return
     */
    public List<T> queryAll() {
        return this.getMapper().select(null);
    }

    /**
     * 根据条件查询一条数据，如果有多条数据会抛出异常
     * 
     * @param record
     * @return
     */
    public T queryOne(T record) {
        return this.getMapper().selectOne(record);
    }

    /**
     * 根据条件查询数据列表
     * 
     * @param record
     * @return
     */
    public List<T> queryListByWhere(T record) {
        return this.getMapper().select(record);
    }

    /**
     * 分页查询
     * 
     * @param page
     * @param rows
     * @param record
     * @return
     */
    public PageInfo<T> queryPageListByWhere(Integer page, Integer rows, T record) {
        // 设置分页条件
        PageHelper.startPage(page, rows);
        List<T> list = this.queryListByWhere(record);
        return new PageInfo<T>(list);
    }

    /**
     * 新增数据，返回成功的条数
     * 
     * @param record
     * @return
     */
    public Integer save(T record) {
        record.setCreated(new Date());
        record.setUpdated(record.getCreated());
        return this.getMapper().insert(record);
    }

    /**
     * 新增数据，使用不为null的字段，返回成功的条数
     * 
     * @param record
     * @return
     */
    public Integer saveSelective(T record) {
        record.setCreated(new Date());
        record.setUpdated(record.getCreated());
        return this.getMapper().insertSelective(record);
    }

    /**
     * 修改数据，返回成功的条数
     * 
     * @param record
     * @return
     */
    public Integer update(T record) {
        return this.getMapper().updateByPrimaryKey(record);
    }

    /**
     * 修改数据，使用不为null的字段，返回成功的条数
     * 
     * @param record
     * @return
     */
    public Integer updateSelective(T record) {
        record.setUpdated(new Date());
        return this.getMapper().updateByPrimaryKeySelective(record);
    }

    /**
     * 根据id删除数据
     * 
     * @param id
     * @return
     */
    public Integer deleteById(Long id) {
        return this.getMapper().deleteByPrimaryKey(id);
    }

    /**
     * 批量删除
     * @param clazz
     * @param property
     * @param values
     * @return
     */
    public Integer deleteByIds(Class<T> clazz, String property, List<Object> values) {
        Example example = new Example(clazz);
        example.createCriteria().andIn(property, values);
        return this.getMapper().deleteByExample(example);
    }

    /**
     * 根据条件做删除
     * 
     * @param record
     * @return
     */
    public Integer deleteByWhere(T record) {
        return this.getMapper().delete(record);
    }


}

Use BaseService to transform ItemCatService

package com.taotao.manage.service;

import java.util.List;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import com.github.abel533.mapper.Mapper;
import com.taotao.manage.mapper.ItemCatMapper;
import com.taotao.manage.pojo.ItemCat;

@Service
public class ItemCatService extends BaseService<ItemCat>{


    @Autowired
    private ItemCatMapper itemCatMapper;

//    public List<ItemCat> queryItemCat(Long parentId) {
//        ItemCat record = new ItemCat();
//        record.setParentId(parentId);
//        return this.itemCatMapper.select(record );
//    }

    @Override
    public Mapper<ItemCat> getMapper() {
        // TODO Auto-generated method stub
        return this.itemCatMapper;
    }

}