mybatisPlus（插件扩展）

	/**
	 * 测试分页插件
	 */
	@Test
	public void testPage() {
		
		Page<Employee> page = new Page<>(1,1);
		
		List<Employee > emps = 
				employeeMapper.selectPage(page, null);
		System.out.println(emps);
				
		System.out.println("===============获取分页相关的一些信息======================");
		
		System.out.println("总条数:" +page.getTotal());
		System.out.println("当前页码: "+  page.getCurrent());
		System.out.println("总页码:" + page.getPages());
		System.out.println("每页显示的条数:" + page.getSize());
		System.out.println("是否有上一页: " + page.hasPrevious());
		System.out.println("是否有下一页: " + page.hasNext());
		
		//将查询的结果封装到page对象中
		page.setRecords(emps);
				
	}

package com.atguigu.mp.mapper;

import com.atguigu.mp.beans.Employee;
import com.baomidou.mybatisplus.mapper.BaseMapper;

/**
 * <p>
 *  Mapper 接口
 * </p>
 *
 * @author weiyunhui
 * @since 2018-06-21
 */
public interface EmployeeMapper extends BaseMapper<Employee> {
	
	int  deleteAll();
}

package com.atguigu.mp.injector;

import org.apache.ibatis.builder.MapperBuilderAssistant;
import org.apache.ibatis.mapping.SqlSource;
import org.apache.ibatis.session.Configuration;

import com.baomidou.mybatisplus.entity.TableInfo;
import com.baomidou.mybatisplus.mapper.AutoSqlInjector;

/**
 * 自定义全局操作
 */
public class MySqlInjector  extends AutoSqlInjector{
	
	/**
	 * 扩展inject 方法，完成自定义全局操作
	 */
	@Override
	public void inject(Configuration configuration, MapperBuilderAssistant builderAssistant, Class<?> mapperClass,
			Class<?> modelClass, TableInfo table) {
		//将EmployeeMapper中定义的deleteAll， 处理成对应的MappedStatement对象，加入到configuration对象中。
		
		//注入的SQL语句
		String sql = "delete from " +table.getTableName();
		//注入的方法名   一定要与EmployeeMapper接口中的方法名一致
		String method = "deleteAll" ;
		
		//构造SqlSource对象
		SqlSource sqlSource = languageDriver.createSqlSource(configuration, sql, modelClass);
		
		//构造一个删除的MappedStatement
		this.addDeleteMappedStatement(mapperClass, method, sqlSource);
		
	}
}

package com.atguigu.mp.beans;

import com.baomidou.mybatisplus.annotations.KeySequence;
import com.baomidou.mybatisplus.annotations.TableField;
import com.baomidou.mybatisplus.annotations.TableId;
import com.baomidou.mybatisplus.annotations.TableLogic;
import com.baomidou.mybatisplus.enums.FieldFill;
import com.baomidou.mybatisplus.enums.IdType;

//@KeySequence(value="seq_user",clazz=Integer.class)
public class User extends Parent {
	//@TableId(type=IdType.INPUT)
	private Integer id  ;

	private String name ;
	
	@TableLogic   // 逻辑删除属性
	private Integer logicFlag ;
	public Integer getId() {
		return id;
	}
	public void setId(Integer id) {
		this.id = id;
	}
	public String getName() {
		return name;
	}
	public void setName(String name) {
		this.name = name;
	}
	public Integer getLogicFlag() {
		return logicFlag;
	}
	public void setLogicFlag(Integer logicFlag) {
		this.logicFlag = logicFlag;
	}
	@Override
	public String toString() {
		return "User [id=" + id + ", name=" + name + ", logicFlag=" + logicFlag + "]";
	}
	
}

package com.atguigu.mp.beans;

import com.baomidou.mybatisplus.annotations.KeySequence;
import com.baomidou.mybatisplus.annotations.TableField;
import com.baomidou.mybatisplus.annotations.TableId;
import com.baomidou.mybatisplus.annotations.TableLogic;
import com.baomidou.mybatisplus.enums.FieldFill;
import com.baomidou.mybatisplus.enums.IdType;

//@KeySequence(value="seq_user",clazz=Integer.class)
public class User extends Parent {
	//@TableId(type=IdType.INPUT)
	private Integer id  ;
	
    //需要被自动填充的字段
	@TableField(fill=FieldFill.INSERT_UPDATE)
	private String name ;
	
	@TableLogic   // 逻辑删除属性
	private Integer logicFlag ;
	public Integer getId() {
		return id;
	}
	public void setId(Integer id) {
		this.id = id;
	}
	public String getName() {
		return name;
	}
	public void setName(String name) {
		this.name = name;
	}
	public Integer getLogicFlag() {
		return logicFlag;
	}
	public void setLogicFlag(Integer logicFlag) {
		this.logicFlag = logicFlag;
	}
	@Override
	public String toString() {
		return "User [id=" + id + ", name=" + name + ", logicFlag=" + logicFlag + "]";
	}
	
}

package com.atguigu.mp.metaObjectHandler;

import org.apache.ibatis.reflection.MetaObject;

import com.baomidou.mybatisplus.mapper.MetaObjectHandler;

/**
 * 自定义公共字段填充处理器
 */
public class MyMetaObjectHandler extends MetaObjectHandler {
	
	/**
	 * 插入操作 自动填充
	 */
	@Override
	public void insertFill(MetaObject metaObject) {
		//获取到需要被填充的字段的值
		Object fieldValue = getFieldValByName("name", metaObject);
		if(fieldValue == null) {
			System.out.println("*******插入操作 满足填充条件*********");
			setFieldValByName("name", "weiyunhui", metaObject);
		}
		
	}
	/**
	 * 修改操作 自动填充
	 */
	@Override
	public void updateFill(MetaObject metaObject) {
		Object fieldValue = getFieldValByName("name", metaObject);
		if(fieldValue == null) {
			System.out.println("*******修改操作 满足填充条件*********");
			setFieldValByName("name", "weiyh", metaObject);
		}
	}

}