Spring 注入数据源
一、在项目中添加dataSource所用到的包
dbcp数据源所需包:
commons-dbcp.jar
commons-pool.jar
C3P0数据源所需包:
c3p0-0.9.1.2.jar
二、在需要用到数据源的类中添加DataSource属性和相应的set方法。
public class StudentDaoImpl implements IStudentDao { //数据库类DataSource在javax.sql包下 private DataSource dataSource; public void save(Student student) { Connection conn=null; try { //通过getConnection()方法得到数据库连接 conn = dataSource.getConnection(); //后面的代码和JDBC一样 PreparedStatement pStat = conn.prepareStatement("insert into student values (?,?)"); pStat.setInt(1, student.getId()); pStat.setString(2, student.getName()); pStat.executeUpdate(); } catch (SQLException e) { e.printStackTrace(); }finally{ try { conn.close(); } catch (SQLException e) { e.printStackTrace(); } } System.out.println("save:"+student.getName()); } //为dataSource属性添加set方法,这样Spring才能把具体的数据源对象注入进来 public void setDataSource(DataSource dataSource) { this.dataSource = dataSource; } }
三、在Spring配置文件中添加DataSource的bean,并注入到用到DataSource的类中
<?xml version="1.0" encoding="UTF-8"?> <beans xmlns="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-2.5.xsd"> <!-- 数据源:C3P0 --> <bean id="dataSource" destroy-method="close" class="com.mchange.v2.c3p0.ComboPooledDataSource"> <!-- 基本属性:数据库驱动类、连接字符串、用户名、密码 --> <property name="driverClass" value="oracle.jdbc.OracleDriver" /> <property name="jdbcUrl" value="jdbc:oracle:thin:@localhost:1521:ORCL" /> <property name="user" value="hib" /> <property name="password" value="hib" /> <!-- 连接数、最小连接数、最大连接数、最大空闲时间 --> <property name="initialPoolSize" value="200"></property> <property name="minPoolSize" value="50"></property> <property name="maxPoolSize" value="300"></property> <property name="maxIdleTime" value="60"></property> </bean> <!-- dbcp数据源配置 --> <!-- <bean id="dataSource" destroy-method="close" class="org.apache.commons.dbcp.BasicDataSource"> <property name="driverClassName" value="oracle.jdbc.OracleDriver"/> <property name="url" value="jdbc:oracle:thin:@localhost:1521:ORCL"/> <property name="username" value="hib"/> <property name="password" value="hib"/> </bean> --> <bean id="studentDao" class="com.startspring.dao.impl.StudentDaoImpl"> <!-- 把dataSource注入给studentDao --> <property name="dataSource" ref="dataSource"></property> </bean> <bean id="studentService" class="com.startspring.service.impl.StudentServiceImpl"> <property name="studentDao" ref="studentDao" /> </bean> <bean id="start" class="com.startspring.Start"> <property name="studentService" ref="studentService" /> </bean> </beans>
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补充:把数据源的属性值写到properties文件中。
一、在项目里添加properties文件,如下:
oracle_c3p0.properties:
jdbc.driverClass=oracle.jdbc.OracleDriver
jdbc.url=jdbc:oracle:thin:@localhost:1521:ORCL
jdbc.user=hib
jdbc.password=hib
key值可以随便起,value值就是数据源的属性值
二、在Spring配置文件中添加propertyConfigurer bean,并把属性值用占位符代替,如下:
<?xml version="1.0" encoding="UTF-8"?> <beans xmlns="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-2.5.xsd"> <!-- 添加propertyConfigurer bean 这个类也是Spring提供的 --> <bean id="propertyConfigurer" class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer"> <!-- 把properties文件的路径注入给location属性,前面要加classpath: --> <property name="location" value="classpath:oracle_c3p0.properties"/> </bean> <!-- 数据源:C3P0 --> <bean id="dataSource" destroy-method="close" class="com.mchange.v2.c3p0.ComboPooledDataSource"> <!-- 现在可以使用${} 占位符了,Spring会去取相应的value值 --> <property name="driverClass" value="${jdbc.driverClass}" /> <property name="jdbcUrl" value="${jdbc.url}" /> <property name="user" value="${jdbc.user}" /> <property name="password" value="${jdbc.password}" /> </bean> <bean id="studentDao" class="com.startspring.dao.impl.StudentDaoImpl"> <!-- 把dataSource注入给studentDao --> <property name="dataSource" ref="dataSource"></property> </bean> <bean id="studentService" class="com.startspring.service.impl.StudentServiceImpl"> <property name="studentDao" ref="studentDao" /> </bean> <bean id="start" class="com.startspring.Start"> <property name="studentService" ref="studentService" /> </bean> </beans>