xml對映檔案的標頭檔案：

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE mapper 
	PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" 
	"http://mybatis.org/dtd/mybatis-3-mapper.dtd">

Book實體類（成員變數與資料庫的一張表的屬性一一對應）：

package com.cm.entity;

import java.util.Date;

import com.mysql.cj.xdevapi.Result;

/**
 * 圖書實體
 */
 

public class Book {
    /**
     * 編號
     */
    private int id;
    /**
     * 書名
     */
    private String title;
    /**
     * 價格
     */
    private double price;
    /**
     * 出版日期
     */
    private Date publishDate;

    public Book(int id, String title, double price, Date publishDate) {
        this
 
.id = id;
        this.title = title;
        this.price = price;
        this.publishDate = publishDate;
    }
    
    public Book() {
    }

    public int getId() {
        return id;
    }

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

    public String getTitle() {
        return
 
 title;
    }

    public void setTitle(String title) {
        this.title = title;
    }

    public double getPrice() {
        return price;
    }

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

    public Date getPublishDate() {
        return publishDate;
    }

    public void setPublishDate(Date publishDate) {
        this.publishDate = publishDate;
    }
    
    public String toString() {
    	String result = "id:" + id
    			+ " title:" + title
    			+ " price:" + price
    			+ " publishDate:" + publishDate;
    	return result;
    }
}

BookDAO介面（定義了對Book所對應的表的各種操作，但沒有實現）:

package com.cm.dao;

import java.util.List;

import org.apache.ibatis.annotations.Param;

import com.cm.entity.Book;



/**
 * 圖書資料訪問介面
 */
public interface BookDAO {
    /**
     * 獲得所有圖書
     */
    public List<Book> getAllBooks();
    /**
     * 根據圖書編號獲得圖書物件
     */
    public Book getBookById(@Param("id") int id);
    /**
     * 新增圖書
     */
    public int add(Book entity);
    /**
     * 根據圖書編號刪除圖書
     */
    public int delete(int id);
    /**
     * 更新圖書
     */
    public int update(Book entity);
}

BookMapper.xml例項（用sql語句實現dao介面的方法）：

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE mapper 
	PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" 
	"http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.cm.dao.BookDAO">
	<select id="getAllBooks" resultType="com.cm.entity.Book">
		select id, title, price, publishDate from books
	</select>
	<select id="getBookById">
		select id, title, price, publishDate from books where id=#{id}
	</select>
	<insert id="add">
        insert into books(title,price,publishDate)
        values(#{title},#{price},#{publishDate})
    </insert>
    <delete id="delete">
        delete from books where id=#{id}
    </delete>
    <update id="update">
        update books set title=#{title},price=#{price},publishDate=#{publishDate}
        where id=#{id}
    </update>
</mapper>

<mapper namespace = “dao介面完整的包名和介面名”>
<select>用於sql查詢語句
<insert>用於sql新增語句
<update>用於sql更新語句
<delete>用於sql刪除語句