Detailed explanation of ibatis learning for Java project construction

driver=com.mysql.jdbc.Driver
url=jdbc:mysql://127.0.0.1:3306/test
username=root
password=root

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE sqlMapConfig PUBLIC "-//ibatis.apache.org//DTD SQL Map Config 2.0//EN"
"http://ibatis.apache.org/dtd/sql-map-config-2.dtd">
<sqlMapConfig>
	<!-- 引用JDBC属性的配置文件 -->
	<properties resource="com/ligang/SqlMap.properties"/>
	<!-- 使用JDBC的事务管理 -->
	<transactionManager type="JDBC">
		<!-- 数据源 -->
		<dataSource type="SIMPLE">
			<property name="JDBC.Driver" value="${driver}"/>
			<property name="JDBC.ConnectionURL" value="${url}"/>
			<property name="JDBC.Username" value="${username}"/>
			<property name="JDBC.Password" value="${password}"/>
		</dataSource>
	</transactionManager>
	<!-- 这里可以写多个实体的映射文件 -->
	<sqlMap resource="com/ligang/Student.xml"/>
</sqlMapConfig>

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE sqlMap PUBLIC "-//ibatis.apache.org//DTD SQL Map 2.0//EN"
"http://ibatis.apache.org/dtd/sql-map-2.dtd">
<sqlMap>
	<!-- 通过typeAlias使得我们在下面使用Student实体类的时候不需要写包名 -->
	<typeAlias alias="Student" type="com.ligang.Student"/>
	
	<!-- id表示select里的sql语句，resultClass表示返回结果的类型 -->
	<select id="findAll" resultClass="Student">
		select * from student
	</select>
	<!-- parameterClass表示参数的内容 -->
	<select id="findByID" parameterClass="String" resultClass="Student">
		select * from student where id = #id#
	</select>
	
	<insert id="insertStudent" parameterClass="Student">
		insert into Student(id,name,age,address) values(#id#,#name#,#age#,#address#)
		<!-- 返回自动增长值 -->
		<selectKey resultClass="String" keyProperty="id">
			select @@identity as inserted
		</selectKey>
	</insert>
	<delete id="deleteStudentByID" parameterClass="String">
		delete from student where id = #id#
	</delete>
	<delete id="deleteStudent" parameterClass="Student">
		delete from Student where id = #id#
	</delete>
	<update id="updateStudent" parameterClass="Student">
		update student set name=#name#,age=#age#,address=#address# where id = #id#
	</update>
	<!-- 模糊查询，使用$代替#。此种方法就是去掉了类型检查，使用字符串连接，不过可能会有sql注入风险-->
	<select id="selectByLike" parameterClass="String" resultClass="Student">
		select * from student where name like &#39;%$name$%&#39;
	</select>
	<!-- 多条件组合查询 -->
	<!-- 方法一(对象构造查询参数) -->
	<!-- 项目中在写ibatis中的sql语句时，where user_id in (#user_id_list# )，运行时总是不行，这里不该用#，而应该用$，区别如下：
		1.#是把传入的数据当作字符串，如#user_id_list#传入的是1,2,则sql语句生成是这样，in (&#39;1,2&#39;) ,当然不可以
		2.$传入的数据直接生成在sql里，如#user_id_list#传入的是1,2,则sql语句生成是这样，in(1,2) 这就对了． 
		3.#方式能够很大程度防止sql注入． 
		4.$方式无法方式sql注入． 
		5.$方式一般用于传入数据库对象．例如传入表名. 
		6.一般能用#的就别用$. 
		直观的说 
		#str# 出来的效果是 &#39;str&#39; 
		$str$ 出来的效果是 str 
		另外 ##只能用在特定的几个地方 $$可以用在任何地方 比如 order by $str$ 
		你甚至可以直接写 $str$ 把 order by 这个字串放在str里传进来 -->
	<select id="findByCon1" parameterClass="Student" resultClass="Student">
		select * from student where name like &#39;%$name$%&#39; and age >= #age#
	</select>
	<!-- 方法二(map封装查询参数) -->
	<parameterMap class="java.util.HashMap" id="paramMap">
		<parameter property="name"/>
		<parameter property="age"/>
	</parameterMap>
	<select id="findByCon2" parameterMap="paramMap" resultClass="Student">
		select * from student where name like ? and age >= ?
	</select>
</sqlMap>

package com.ligang;
import java.io.IOException;
import java.io.Reader;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import com.ibatis.common.resources.Resources;
import com.ibatis.sqlmap.client.SqlMapClient;
import com.ibatis.sqlmap.client.SqlMapClientBuilder;
public class StudentDaoImpl implements StudentDao {
	public static SqlMapClient sqlMapClient = null;
	static{
		try {
			Reader reader = Resources.getResourceAsReader("com/ligang/SqlMapConfig.xml");
			sqlMapClient = SqlMapClientBuilder.buildSqlMapClient(reader);
		} catch (IOException e) {
			e.printStackTrace();
		}
	}
	public List<Student> findAll() {
		List<Student> list = null;
		try {
			list = sqlMapClient.queryForList("findAll");
		} catch (SQLException e) {
			e.printStackTrace();
		}
		return list;
	}
	public Student findByID(String id){
		Student student = null;
		try {
			 student = (Student) sqlMapClient.queryForObject("findByID", id);
		} catch (SQLException e) {
			e.printStackTrace();
		}
		return student;
	}
	public void addStudent(Student student){
		try {
			sqlMapClient.insert("insertStudent",student);
		} catch (SQLException e) {
			e.printStackTrace();
		}
	}
	public void deleteStudentByID(String id){
		try {
			sqlMapClient.delete("deleteStudentByID",id);
		} catch (SQLException e) {
			e.printStackTrace();
		}
	}
	public void deleteStudent(Student student){
		try {
			sqlMapClient.delete("deleteStudent",student);
		} catch (SQLException e) {
			e.printStackTrace();
		}
	}
	public void updateStudent(Student student){
		try {
			sqlMapClient.update("updateStudent", student);
		} catch (SQLException e) {
			e.printStackTrace();
		}
	}
	public List<Student> findByCon(String name){
		List<Student> stuList = new ArrayList<Student>();
		try {
			stuList = sqlMapClient.queryForList("selectByLike",name);
		} catch (SQLException e) {
			e.printStackTrace();
		}
		return stuList;
	}
	public List<Student> findByCon(Student student){
		List<Student> stuList = new ArrayList<Student>();
		try {
			stuList = sqlMapClient.queryForList("findByCon1",student);
		} catch (SQLException e) {
			e.printStackTrace();
		}
		return stuList;
	}
	public List<Student> findByCon(Map map){
		List<Student> stuList = new ArrayList<Student>();
		try {
			stuList = sqlMapClient.queryForList("findByCon2",map);
		} catch (SQLException e) {
			e.printStackTrace();
		}
		return stuList;
	}
}