Mini MyBatis-Plus(下)

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最核心的内容前两篇已经讲完了，这一篇只有代码：

先看demo目录下的三个文件：

DemoApplication.java

package com.example.demo;

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

@SpringBootApplication
public class DemoApplication {

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

}

User.java

package com.example.demo;

import com.example.demo.mybatisplus.annotations.TableName;
import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;

import java.util.Date;

/**
 * @author mx
 */
@Data
@TableName("t_user")
@AllArgsConstructor
@NoArgsConstructor
public class User {
    private Long id;
    private String name;
    private Integer age;
    private Date birthday;
}

UserMapper.java

package com.example.demo;

import com.example.demo.mybatisplus.AbstractBaseMapper;

/**
 * @author mx
 */
public class UserMapper extends AbstractBaseMapper {
}

mybatisplus下AbstractBaseMapper.java

package com.example.demo.mybatisplus;

import com.example.demo.mybatisplus.annotations.TableName;
import com.example.demo.mybatisplus.core.JdbcTemplate;
import com.example.demo.mybatisplus.query.QueryWrapper;
import com.example.demo.mybatisplus.query.SqlParam;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.lang.reflect.Field;
import java.lang.reflect.ParameterizedType;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import java.util.Map;

/**
 * Mapper基类
 *
 * @author mx
 */
public abstract class AbstractBaseMapper {

    private static Logger logger = LoggerFactory.getLogger(AbstractBaseMapper.class);

    private JdbcTemplate jdbcTemplate = new JdbcTemplate();

    private Class beanClass;

    private final String TABLE_NAME;

    private static final String DEFAULT_LOGICAL_TYPE = " and ";

    public AbstractBaseMapper() {
        // DO对象的Class
        beanClass = (Class) ((ParameterizedType) this.getClass()
                .getGenericSuperclass())
                .getActualTypeArguments()[0];
        // DO对应的表名 TODO 非空判断及默认处理
        TABLE_NAME = beanClass.getAnnotation(TableName.class).value();
    }

    public T select(QueryWrapper queryWrapper) {
        List list = this.list(queryWrapper);
        if (!list.isEmpty()) {
            return list.get(0);
        }

        return null;
    }

    public List list(QueryWrapper queryWrapper) {
        StringBuilder sqlBuilder = new StringBuilder("SELECT * FROM ").append(TABLE_NAME).append(" WHERE ");

        List