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1.1数据源(连接池)使用
数据源为提高程序性能出现
实例化数据源,初始化连接资源
使用资源时从数据源中获取
使用完毕将连接资源归还给数据源
常见数据源:DBCP C3P0 BoneCP Druid
1.1数据源开发步骤
1导入数据源的坐标和数据库驱动坐标
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>5.1.47</version>
</dependency>
<dependency>
<groupId>c3p0</groupId>
<artifactId>c3p0</artifactId>
<version>0.9.1.2</version>
</dependency>
<dependency>
<groupId>com.alibaba</groupId>
<artifactId>druid</artifactId>
<version>1.1.10</version>
</dependency>
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>4.12</version>
<scope>test</scope>
</dependency>
2 创建数据源对象
@Test
//测试手动创建 c3p0数据源
public void dataSourceTest() throws Exception {
ComboPooledDataSource dataSource = new ComboPooledDataSource();
dataSource.setDriverClass("com.mysql.jdbc.Driver");
dataSource.setJdbcUrl("jdbc:mysql://localhost:3306/test");
dataSource.setUser("root");
dataSource.setPassword("root");
Connection connection = dataSource.getConnection();
System.out.println(connection);
connection.close();
}
@Test
public void druidTest() throws Exception{
DruidDataSource druidDataSource = new DruidDataSource();
druidDataSource.setDriverClassName("com.mysql.jdbc.Driver");
druidDataSource.setUrl("jdbc:mysql://localhost:3306/test");
druidDataSource.setUsername("root");
druidDataSource.setPassword("root");
DruidPooledConnection connection = druidDataSource.getConnection();
System.out.println(connection);
connection.close();
}
2 设置数据源基本的连接数据
1.2 抽取jdbc.properties配置文件
1.在resources下新建jdbc.properties配置文件
2.配置
jdbc.driver=com.mysql.jdbc.Driver
jdbc.url=jdbc:mysql://localhost:3306/test
jdbc.user=root
jdbc.password=root
3.读取properties配置文件
@Test //测试c3p0数据源(使用properties配置文件)
public void c3p0Test() throws Exception {
ResourceBundle jdbc = ResourceBundle.getBundle("jdbc");
String driver = jdbc.getString("jdbc.driver");
String url = jdbc.getString("jdbc.url");
String user = jdbc.getString("jdbc.user");
String password = jdbc.getString("jdbc.password");
ComboPooledDataSource dataSource = new ComboPooledDataSource();
dataSource.setDriverClass(driver);
dataSource.setJdbcUrl(url);
dataSource.setUser(user);
dataSource.setPassword(password);
Connection connection = dataSource.getConnection();
System.out.println(connection);
connection.close();
}
1.3 Spring配置数据源
可以将dataSource的创建权交给Spring容器
1.导入Spring 坐标
2.创建配置文件
<bean id="druidDataSource" class="com.alibaba.druid.pool.DruidDataSource">
<property name="driverClassName" value="com.mysql.jdbc.Driver"></property>
<property name="url" value="jdbc:mysql://localhost:3306/test"></property>
<property name="username" value="root"></property>
<property name="password" value="root"></property>
</bean>
3.从Spring容器中获取bean
@Test
public void testSpringContext() throws Exception {
ApplicationContext app=new ClassPathXmlApplicationContext("applicationContext.xml");
DruidDataSource druidDataSource = app.getBean(DruidDataSource.class);
DruidPooledConnection connection = druidDataSource.getConnection();
System.out.println(connection);
connection.close();
}
1.4 Spring加载properties配置文件
1.配置.xml
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:context="http://www.springframework.org/schema/context"
xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd">
<context:property-placeholder location="classpath:jdbc.properties"/>
<bean id="druidDataSource" class="com.alibaba.druid.pool.DruidDataSource">
<property name="driverClassName" value="${jdbc.driver}"></property>
<property name="url" value="${jdbc.url}"></property>
<property name="username" value="${jdbc.user}"></property>
<property name="password" value="${jdbc.password}"></property>
</bean>
</beans>