第一个通过的ibatis操作mysql的实际例子_MySQL
iBATIS
bitsCN.com步骤如下:
1,在eclipse中新建一个工程ibatisnew,然后把mysql和ibatis的jar包导入进去。这两个包(ibatis-2.3.4.726.jar+mysql-connector-java-5.0.8-bin.jar)可以从网上下载,直接拷贝到WEB-INF/lib目录下。
2,建立SqlMapConfig.xml文件
这个文件包含了数据库的配置,和各个数据表对应的xml的引用部分。
文件名:SqlMapConfig.xml
文件内容:
nbsp;
PUBLIC "-//ibatis.apache.org//DTD SQL Map Config 2.0//EN"
"http://ibatis.apache.org/dtd/sql-map-config-2.dtd">
3,建立SqlMapConfig.xml中引用的User.xml文件,
这个文件对应数据库中的user表,在这个文件中可以定义别名,可以写sql语句。
文件名:User.xml
文件内容:
nbsp;
PUBLIC "-//ibatis.apache.org//DTD SQL Map 2.0//EN"
"http://ibatis.apache.org/dtd/sql-map-2.dtd">
4,建立user.xml文件中指定的class的文件
这个文件就是一个javabean,和数据库的表的字段相对应,有set和get方法。
文件名;User.java
文件内容:
package test_ibatis;
import java.sql.Date;
public class User {
@Override
public String toString() {
// TODO Auto-generated method stub
String str = "id = " + this.id;
str += " name = " + this.name;
str += " birthday = " + this.birthday;
str += " money = " + this.money;
return str;
}
private int id;
private String name;
private Date birthday;
private float money;
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public Date getBirthday() {
return birthday;
}
public void setBirthday(Date birthday) {
this.birthday = birthday;
}
public float getMoney() {
return money;
}
public void setMoney(float money) {
this.money = money;
}
}
5,建立DAO程序和实现程序
接口名:IUserDAO.java
内容:
package test_ibatis;
import java.util.List;
public interface IUserDAO {
public List
}
实现类:IUserDAOImpl.java
内容:
package test_ibatis;
import java.io.IOException;
import java.io.Reader;
import java.sql.SQLException;
import java.util.List;
import com.ibatis.common.resources.Resources;
import com.ibatis.sqlmap.client.SqlMapClient;
import com.ibatis.sqlmap.client.SqlMapClientBuilder;
public class IUserDAOImpl implements IUserDAO {
private static SqlMapClient client = null;
static {
try {
Reader reader = Resources.getResourceAsReader("test_ibatis/SqlMapConfig.xml");
client = SqlMapClientBuilder.buildSqlMapClient(reader);
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
public List
// TODO Auto-generated method stub
try {
return client.queryForList("selectAllUsers");
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return null;
}
}
1,实现类中要使用ibatis提供的功能,先从xml文件中读取配置,构造SqlMapClient的对象。
2,具体的实现方法,通过调用SqlMapClient提供的方法,指定xml中的id即可执行对应的sql,并返回结果。
6,测试class
文件名:UserDAO.java
文件内容:
package test_ibatis;
public class UserDAO {
/**
* @param args
*/
public static void main(String[] args) {
// TODO Auto-generated method stub
IUserDAO dao = new IUserDAOImpl();
for (User user : dao.getAllUser()) {
System.out.println(user);
}
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