Spring加载外部的properties文件的简单实践

注意：

使用xml配置关注 1.1 1.2 1.5

使用配置类配置关注 1.1 1.3 1.4 1.5

1.1 新建jdbc.properties

jdbc.driver=com.mysql.jdbc.Driver
jdbc.url=jdbc:mysql://localhost:3306/test?serverTimezone=UTC&characterEncoding=UTF-8
jdbc.username=root
jdbc.password=root

1.2 新建applicationContext.xml )

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:context="http://www.springframework.org/schema/context"
       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.xsd
                http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd">

    <!-- 加载外部的properties文件 -->
    <context:property-placeholder location="classpath:jdbc.properties"></context:property-placeholder>

    <bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource">
        <property name="driverClass" value="${jdbc.driver}" ></property>
        <property name="jdbcUrl" value="${jdbc.url}"></property>
        <property name="user" value="${jdbc.username}"></property>
        <property name="password" value="${jdbc.password}"></property>
    </bean>
</beans>

 

1.3  新建DataSourceConfiguration.java  （数据源类 注意文件中的Bean配置）

package com.zhan.config;

import com.mchange.v2.c3p0.ComboPooledDataSource;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.PropertySource;

import javax.sql.DataSource;
import java.beans.PropertyVetoException;

@PropertySource("classpath:jdbc.properties")
public class DataSourceConfiguration {
    @Value("${jdbc.driver}")
    private String driver;

    @Value("${jdbc.url}")
    private String url;

    @Value("${jdbc.username}")
    private String user;

    @Value("${jdbc.password}")
    private String password;

    @Bean("dataSource") //Spring会将当前方法的返回值以指定名称存储到Spring容器中
    public DataSource getDataSource() {
        ComboPooledDataSource dataSource = new ComboPooledDataSource();
        try {
            dataSource.setDriverClass(driver);
            dataSource.setJdbcUrl(url);
            dataSource.setUser(user);
            dataSource.setPassword(password);
        } catch (PropertyVetoException e) {
            e.printStackTrace();
        }
        return dataSource;
    }
}

 

1.4 编写配置类 SpringConfiguration.java

package com.zhan.config;


import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Import;

@Configuration
@ComponentScan("com.zhan")
@Import({DataSourceConfiguration.class})
public class SpringConfiguration {


}

 

1.5 编写Junit测试类

package com.zhan.test;

import com.zhan.config.SpringConfiguration;
import com.zhan.service.UserService;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.test.context.ContextConfiguration;
import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;

@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration(value="classpath:applicationContext.xml")
//@ContextConfiguration(classes = {SpringConfiguration.class})
@ComponentScan("com.zhan")
public class SpringJunitTest {
    @Autowired
    private UserService userService;

    @Test
    public void test1(){
        userService.save();
    }
}