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The main content of this article is a brief introduction to ibatis and how to build a JAVA project through iBatis. It also includes a related example. Friends in need can refer to it.
Introduction to IBATIS
ibatis is an open source project of Apache, an ORM solution. The biggest feature of ibatis is that it is small and easy to use.
Using the ORM mechanism provided by ibatis, for business logic implementers, they are faced with pure Java objects. This layer is basically consistent with implementing ORM through Hibernate.
iBatis is a persistence layer framework based on SQL mapping that supports Java and .NET. Compared with "one-stop" ORM solutions such as Hibernate and ApacheOJB, iBatis is a "semi-automated" ORM implementation.
1. JAR package dependency
ibatis-2.3.4.726.jar
mysql-connector-java -5.0.8-bin.jar
##2. SqlMap.properties
driver=com.mysql.jdbc.Driver url=jdbc:mysql://127.0.0.1:3306/test username=root password=root
3. SqlMapConfig.xml
<?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>
4. Student.xml
<?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$代替#。此种方法就是去掉了类型检查,使用字符串连接,不过可能会有sql注入风险--> <select id="selectByLike" parameterClass="String" resultClass="Student"> select * from student where name like '%$name$%' </select> <!-- 多条件组合查询 --> <!-- 方法一(对象构造查询参数) --> <!-- 项目中在写ibatis中的sql语句时,where user_id in (#user_id_list# ),运行时总是不行,这里不该用#,而应该用$,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 ('1,2') ,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 'str' $str$ 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 '%$name$%' 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>
5. JAVA code
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; } }
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