第一种:实现ApplicationListener<ContextRefreshedEvent>接口
package bdc.base;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import javax.annotation.Resource;
import org.springframework.context.ApplicationListener;
import org.springframework.context.event.ContextRefreshedEvent;
import bdc.ws.dao.CommonDao;
import bdc.ws.entity.RsaKey;
//@Component 使用这个注解或者采用bean注入<bean id="afterSpringBegin" class="bdc.base.AfterSpringBegin"></bean>
public class AfterSpringBegin implements
ApplicationListener<ContextRefreshedEvent> {
@Resource
private CommonDao commonDao;
public static final Map<String, RsaKey> KEY_RSA = new HashMap<String, RsaKey>();
@Override
public void onApplicationEvent(ContextRefreshedEvent event) {
if (event.getApplicationContext().getParent() == null) {
try {
List<RsaKey> selectAllRsaKey = commonDao.selectAllRsaKey();
for (int i = 0; i < selectAllRsaKey.size(); i++) {
KEY_RSA.put(selectAllRsaKey.get(i).getUserOrg(),selectAllRsaKey.get(i));
}
} catch (Exception e) {
e.printStackTrace();
}
}
}
}
第二种使用@PostConstruct注解
@Component
public class TuneNetInterface {
private static Client client;
private static QName opName;
@Value("${WebUrl}")
private String WebUrl;
@Value("${operation}")
private String operation;
@PostConstruct
public void init() { //以下为具体逻辑
JaxWsDynamicClientFactory factory = JaxWsDynamicClientFactory
.newInstance(BusFactory.newInstance().createBus());
client = factory.createClient(WebUrl);
Endpoint endpoint = client.getEndpoint();
opName = new QName(endpoint.getService().getName().getNamespaceURI(),
operation);
BindingInfo bindingInfo = endpoint.getEndpointInfo().getBinding();
if (bindingInfo.getOperation(opName) == null) {
for (BindingOperationInfo operationInfo : bindingInfo.getOperations()) {
if (operation.equals(operationInfo.getName().getLocalPart())) {
opName = operationInfo.getName();
break;
}
}
}
}
public static Object[] request(String content) throws Exception {
return client.invoke(opName, content);
}
}
第三种:使用@Configuration注解
package com.dxz.demo.configuration;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Scope;
@Configuration
//添加自动扫描注解,basePackages为TestBean包路径
@ComponentScan(basePackages = "com.dxz.demo.configuration")
public class TestConfiguration {
public TestConfiguration() {
System.out.println("TestConfiguration容器启动初始化。。。");
}
/*// @Bean注解注册bean,同时可以指定初始化和销毁方法
// @Bean(name="testNean",initMethod="start",destroyMethod="cleanUp")
@Bean
@Scope("prototype")
public TestBean testBean() {
return new TestBean();
}*/
}
从Spring3.0,@Configuration用于定义配置类,可替换xml配置文件,被注解的类内部包含有一个或多个被@Bean注解的方法,这些方法将会被AnnotationConfigApplicationContext或AnnotationConfigWebApplicationContext类进行扫描,并用于构建bean定义,初始化Spring容器。
注意:@Configuration注解的配置类有如下要求:
@Configuration不可以是final类型;
@Configuration不可以是匿名类;
嵌套的configuration必须是静态类。
一、用@Configuration加载spring
1.1、@Configuration配置spring并启动spring容器
1.2、@Configuration启动容器+@Bean注册Bean
1.3、@Configuration启动容器+@Component注册Bean
1.4、使用 AnnotationConfigApplicationContext 注册 AppContext 类的两种方法
1.5、配置Web应用程序(web.xml中配置AnnotationConfigApplicationContext)
二、组合多个配置类
2.1、在@configuration中引入spring的xml配置文件
2.2、在@configuration中引入其它注解配置
2.3、@configuration嵌套(嵌套的Configuration必须是静态类)
三、@EnableXXX注解
四、@Profile逻辑组配置
五、使用外部变量
一、@Configuation加载Spring方法
1.1、@Configuration配置spring并启动spring容器
@Configuration标注在类上,相当于把该类作为spring的xml配置文件中的<beans>,作用为:配置spring容器(应用上下文)
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package com.dxz.demo.configuration;
import org.springframework.context.annotation.Configuration;
@Configuration
public class TestConfiguration {
public TestConfiguration() {
System.out.println("TestConfiguration容器启动初始化。。。");
}
}
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相当于:
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<?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" xmlns:jdbc="http://www.springframework.org/schema/jdbc"
xmlns:jee="http://www.springframework.org/schema/jee" xmlns:tx="http://www.springframework.org/schema/tx"
xmlns:util="http://www.springframework.org/schema/util" xmlns:task="http://www.springframework.org/schema/task" xsi:schemaLocation="
http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-4.0.xsd
http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.0.xsd
http://www.springframework.org/schema/jdbc http://www.springframework.org/schema/jdbc/spring-jdbc-4.0.xsd
http://www.springframework.org/schema/jee http://www.springframework.org/schema/jee/spring-jee-4.0.xsd
http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-4.0.xsd
http://www.springframework.org/schema/util http://www.springframework.org/schema/util/spring-util-4.0.xsd
http://www.springframework.org/schema/task http://www.springframework.org/schema/task/spring-task-4.0.xsd" default-lazy-init="false">
</beans>
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主方法进行测试:
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package com.dxz.demo.configuration;
import org.springframework.context.ApplicationContext;
import org.springframework.context.annotation.AnnotationConfigApplicationContext;
public class TestMain {
public static void main(String[] args) {
// @Configuration注解的spring容器加载方式,用AnnotationConfigApplicationContext替换ClassPathXmlApplicationContext
ApplicationContext context = new AnnotationConfigApplicationContext(TestConfiguration.class);
// 如果加载spring-context.xml文件:
// ApplicationContext context = new
// ClassPathXmlApplicationContext("spring-context.xml");
}
}
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从运行主方法结果可以看出,spring容器已经启动了:
SpringBoot项目初始化1、 创建自定义类实现 CommandLineRunner接口,重写run()方法。springboot启动之后会默认去扫描所有实现了CommandLineRunner的类,并运行其run()方法。
@Component
@Order(2) //通过order值的大小来决定启动的顺序
public class AskForLeave implements CommandLineRunner {
@Override
public void run(String... args) throws Exception {
askForLeave();
}
public void askForLeave(){
System.out.println("项目启动了,执行了方法");
}
}
2、创建自定义类实现ApplicationRunner 接口,重写run()方法。
@Component
@Order(3)
public class Hello implements ApplicationRunner {
@Override
public void run(ApplicationArguments args) throws Exception {
hello();
}
public void hello(){
System.out.println("项目又启动了,这次使用的是:继承 ApplicationRunner");
}
}
关于二者的区别:
其实并没有什么区别,如果想获取更加详细的参数的时候,可以选择使用ApplicationRunner接口。其参数类型为:ApplicationArguments 。