java mybatis框架如何配置

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE configuration PUBLIC "-//mybatis.org//DTD Config 3.0//EN"
"http://mybatis.org/dtd/mybatis-3-config.dtd">
 
<configuration>
<!-- 加载类路径下的属性文件 -->
<properties resource="db.properties"/>
 
<!-- 设置一个默认的连接环境信息 -->
<environments default="mysql_developer">
<!-- 连接环境信息，取一个任意唯一的名字 -->
<environment id="mysql_developer">
<!-- mybatis使用jdbc事务管理方式 -->
<transactionManager type="jdbc"/>
<!-- mybatis使用连接池方式来获取连接 -->
<dataSource type="pooled">
<!-- 配置与数据库交互的4个必要属性 -->
<property name="driver" value="${mysql.driver}"/>
<property name="url" value="${mysql.url}"/>
<property name="username" value="${mysql.username}"/>
<property name="password" value="${mysql.password}"/>
</dataSource>
</environment>
<!-- 连接环境信息，取一个任意唯一的名字 -->
<environment id="oracle_developer">
<!-- mybatis使用jdbc事务管理方式 -->
<transactionManager type="jdbc"/>
<!-- mybatis使用连接池方式来获取连接 -->
<dataSource type="pooled">
<!-- 配置与数据库交互的4个必要属性 -->
<property name="driver" value="${oracle.driver}"/>
<property name="url" value="${oracle.url}"/>
<property name="username" value="${oracle.username}"/>
<property name="password" value="${oracle.password}"/>
</dataSource>
</environment>
</environments>
</configuration>

public static SqlSessionFactory getSqlSessionFactoryUsingJavaAPI() {
    if (javaSqlSessionFactory == null) {
        try {
            DataSource dataSource = DataSourceFactory.getDataSource();
            TransactionFactory transactionFactory = new JdbcTransactionFactory();
            Environment environment = new Environment("development", transactionFactory, dataSource);
            Configuration configuration = new Configuration(environment);
            configuration.getTypeAliasRegistry().registerAlias("student", Student.class);
            configuration.getTypeHandlerRegistry().register(PhoneTypeHandler.class);
            configuration.addMapper(StudentMapper.class);
            javaSqlSessionFactory = new SqlSessionFactoryBuilder().build(configuration);
 
        } catch (Exception e) {
            throw new RuntimeException(e);
        }
    }
    return javaSqlSessionFactory;
}