Spring 实战学习笔记（第三章 Bean的高级装配）

一、开发环境、测试环境与生产环境加载不同数据的配置方式

　　1.@Profile注解应用　　

　　　@Profile注解配置方式，

　　　　1）配置在类上（只有prod或者dev profile激活时，才会创建对应的bean）　

package com.myapp;

import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Profile;
import org.springframework.jdbc.datasource.embedded.EmbeddedDatabaseBuilder;

import javax.sql.DataSource;

@Configuration
@Profile("dev")
public class DevelopmentProfileConfig {

    @Bean(destroyMethod = "shutdown")
    public DataSource dataSource() {
        return new EmbeddedDatabaseBuilder()
                .addScript("classpath:schema.sql")
                .addScript("classpath:test-data.sql")
                .build();
    }
}

package com.myapp;

import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Profile;
import org.springframework.jndi.JndiObjectFactoryBean;

import javax.sql.DataSource;

@Configuration
@Profile("prod")
public class ProductionProfileConfig {

    @Bean(destroyMethod = "shutdown")
    public DataSource jndiDataSource() {
        JndiObjectFactoryBean jndiObjectFactoryBean = new JndiObjectFactoryBean();
        jndiObjectFactoryBean.setJndiName("jdbc/myDS");
        jndiObjectFactoryBean.setResourceRef(true);
        jndiObjectFactoryBean.setProxyInterface(javax.sql.DataSource.class);
        return (DataSource) jndiObjectFactoryBean.getObject();
    }
}

　　　　2）配置在方法上（3.1之后版本开始支持，之前版本不支持，只有当规定的profile激活时，相应的bean才会被创建，没有指定profile的bean始终都会被创建）

package com.myapp;

import javax.sql.DataSource;

import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Profile;
import org.springframework.jdbc.datasource.embedded.EmbeddedDatabaseBuilder;
import org.springframework.jdbc.datasource.embedded.EmbeddedDatabaseType;
import org.springframework.jndi.JndiObjectFactoryBean;

@Configuration
public class DataSourceConfig {
  
  @Bean(destroyMethod = "shutdown")
  @Profile("dev")
  public DataSource embeddedDataSource() {
    return new EmbeddedDatabaseBuilder()
        .setType(EmbeddedDatabaseType.H2)
        .addScript("classpath:schema.sql")
        .addScript("classpath:test-data.sql")
        .build();
  }

  @Bean
  @Profile("prod")
  public DataSource jndiDataSource() {
    JndiObjectFactoryBean jndiObjectFactoryBean = new JndiObjectFactoryBean();
    jndiObjectFactoryBean.setJndiName("jdbc/myDS");
    jndiObjectFactoryBean.setResourceRef(true);
    jndiObjectFactoryBean.setProxyInterface(javax.sql.DataSource.class);
    return (DataSource) jndiObjectFactoryBean.getObject();
  }

}

　　2、基于xml配置方式

<?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:jdbc="http://www.springframework.org/schema/jdbc"
  xmlns:jee="http://www.springframework.org/schema/jee" xmlns:p="http://www.springframework.org/schema/p"
  xsi:schemaLocation="
    http://www.springframework.org/schema/jee
    http://www.springframework.org/schema/jee/spring-jee.xsd
    http://www.springframework.org/schema/jdbc
    http://www.springframework.org/schema/jdbc/spring-jdbc.xsd
    http://www.springframework.org/schema/beans
    http://www.springframework.org/schema/beans/spring-beans.xsd">

  <beans profile="dev">
    <jdbc:embedded-database id="dataSource" type="H2">
      <jdbc:script location="classpath:schema.sql" />
      <jdbc:script location="classpath:test-data.sql" />
    </jdbc:embedded-database>
  </beans>
  
  <beans profile="prod">
    <jee:jndi-lookup id="dataSource"
      lazy-init="true"
      jndi-name="jdbc/myDatabase"
      resource-ref="true"
      proxy-interface="javax.sql.DataSource" />
  </beans>
</beans>

二、激活profile

　　Spring在确定那个profile处于激活状态是，需要依赖两个独立的属性：spring.profiles.active和spring.profiles.default。优先级spring.profiles.active > spring.profiles.default

如果这两个参数都没有设置的情况下，profile不会激活，只会创建没有定义在profile中的bean

　　profile激活方式：

　　1）作为DispatcherServlet的初始化参数；

　　2）作为Web应用的上下文参数；

　　3）作为JNDI条目；

　　4）作为环境变量；

　　5）作为JVM的系统属性；

　　6）在继承测试类上，使用@ActiveProfiles注解设置

在Servlet上下文中配置如下：

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" 
  xmlns="http://java.sun.com/xml/ns/javaee" 
  xsi:schemaLocation="http://java.sun.com/xml/ns/javaee 
  http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd" id="WebApp_ID" version="2.5">
  <display-name>SpringDemo</display-name>
  <context-param>
      <param-name>contextConfigLocation</param-name>
      <param-value>/WEB-INF/spring/root-context.xml</param-value>
  </context-param>
  <context-param>
      <param-name>spring.profiles.default</param-name>
      <param-value>dev</param-value>
  </context-param>
  <listener>
      <listener-class>
          org.springframework.web.context.ContextLoaderListener
      </listener-class>
  </listener>
  <servlet>
      <servlet-name>appServlet</servlet-name>
      <servlet-class>
          org.springframework.web.servlet.DispatcherServlet
      </servlet-class>
      <init-param>
          <param-name>spring.profiles.default</param-name>
          <param-value>dev</param-value>
      </init-param>
      <load-on-startup>1</load-on-startup>
  </servlet>
  
  <servlet-mapping>
      <servlet-name>appServlet</servlet-name>
      <url-pattern>/</url-pattern>
  </servlet-mapping>
</web-app>

spring.profiles.active和spring.profiles.default支持同时激活多个profile，可以通过列出多个profile名称，并以逗号分隔来实现