网站推广的网站作用,郑州 服装 网站建设,自己做装修效果的网站,熟练做网站需要了解什么Configuration
从Spring3.0#xff0c;Configuration用于定义配置类#xff0c;可替换xml配置文件#xff0c;被注解的类内部包含有一个或多个被Bean注解的方法#xff0c;这些方法将会被AnnotationConfigApplicationContext或AnnotationConfigWebApplicationContext类进行…Configuration
从Spring3.0Configuration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配置文件中的作用为配置spring容器(应用上下文)
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。。。);}
}?xml version1.0 encodingUTF-8?
beans xmlnshttp://www.springframework.org/schema/beans xmlns:xsihttp://www.w3.org/2001/XMLSchema-instancexmlns:contexthttp://www.springframework.org/schema/context xmlns:jdbchttp://www.springframework.org/schema/jdbc xmlns:jeehttp://www.springframework.org/schema/jee xmlns:txhttp://www.springframework.org/schema/txxmlns:utilhttp://www.springframework.org/schema/util xmlns:taskhttp://www.springframework.org/schema/task xsi:schemaLocationhttp://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-4.0.xsdhttp://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.0.xsdhttp://www.springframework.org/schema/jdbc http://www.springframework.org/schema/jdbc/spring-jdbc-4.0.xsdhttp://www.springframework.org/schema/jee http://www.springframework.org/schema/jee/spring-jee-4.0.xsdhttp://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-4.0.xsdhttp://www.springframework.org/schema/util http://www.springframework.org/schema/util/spring-util-4.0.xsdhttp://www.springframework.org/schema/task http://www.springframework.org/schema/task/spring-task-4.0.xsd default-lazy-initfalse/beanspackage 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ClassPathXmlApplicationContextApplicationContext context new AnnotationConfigApplicationContext(TestConfiguration.class);// 如果加载spring-context.xml文件// ApplicationContext context new// ClassPathXmlApplicationContext(spring-context.xml);}
}1.2、Configuration启动容器Bean注册BeanBean下管理bean的生命周期 Bean标注在方法上(返回某个实例的方法)等价于spring的xml配置文件中的作用为注册bean对象
bean类
package com.dxz.demo.configuration;public class TestBean {private String username;private String url;private String password;public void sayHello() {System.out.println(TestBean sayHello...);}public String toString() {return username: this.username ,url: this.url ,password: this.password;}public void start() {System.out.println(TestBean 初始化。。。);}public void cleanUp() {System.out.println(TestBean 销毁。。。);}
}package com.dxz.demo.configuration;import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Scope;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(nametestBean,initMethodstart,destroyMethodcleanUp)BeanScope(prototype)public TestBean testBean() {return new TestBean();}
}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ClassPathXmlApplicationContextApplicationContext context new AnnotationConfigApplicationContext(TestConfiguration.class);// 如果加载spring-context.xml文件// ApplicationContext context new// ClassPathXmlApplicationContext(spring-context.xml);//获取beanTestBean tb (TestBean) context.getBean(testBean);tb.sayHello();}
}注 (1)、Bean注解在返回实例的方法上如果未通过Bean指定bean的名称则默认与标注的方法名相同 (2)、Bean注解默认作用域为单例singleton作用域可通过Scope(“prototype”)设置为原型作用域 (3)、既然Bean的作用是注册bean对象那么完全可以使用Component、Controller、Service、Ripository等注解注册bean当然需要配置ComponentScan注解进行自动扫描。 Bean下管理bean的生命周期 可以使用基于 Java 的配置来管理 bean 的生命周期。Bean 支持两种属性即 initMethod 和destroyMethod这些属性可用于定义生命周期方法。在实例化 bean 或即将销毁它时容器便可调用生命周期方法。生命周期方法也称为回调方法因为它将由容器调用。使用 Bean 注释注册的 bean 也支持 JSR-250 规定的标准 PostConstruct 和 PreDestroy 注释。如果您正在使用 XML 方法来定义 bean那么就应该使用 bean 元素来定义生命周期回调方法。以下代码显示了在 XML 配置中通常使用 bean 元素定义回调的方法。
Configuration
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(nametestBean,initMethodstart,destroyMethodcleanUp)Scope(prototype)public TestBean testBean() {return new TestBean();}
}public class TestMain {public static void main(String[] args) {ApplicationContext context new AnnotationConfigApplicationContext(TestConfiguration.class);TestBean tb (TestBean) context.getBean(testBean);tb.sayHello();System.out.println(tb);TestBean tb2 (TestBean) context.getBean(testBean);tb2.sayHello();System.out.println(tb2);}
}分析
结果中的1表明initMethod生效
结果中的2表明Scope(“prototype”)生效 1.3、Configuration启动容器Component注册Bean bean类
package com.dxz.demo.configuration;import org.springframework.stereotype.Component;//添加注册bean的注解
Component
public class TestBean {private String username;private String url;private String password;public void sayHello() {System.out.println(TestBean sayHello...);}public String toString() {return username: this.username ,url: this.url ,password: this.password;}public void start() {System.out.println(TestBean 初始化。。。);}public void cleanUp() {System.out.println(TestBean 销毁。。。);}
}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(nametestNean,initMethodstart,destroyMethodcleanUp)BeanScope(prototype)public TestBean testBean() {return new TestBean();}*/
}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ClassPathXmlApplicationContextApplicationContext context new AnnotationConfigApplicationContext(TestConfiguration.class);// 如果加载spring-context.xml文件// ApplicationContext context new// ClassPathXmlApplicationContext(spring-context.xml);//获取beanTestBean tb (TestBean) context.getBean(testBean);tb.sayHello();}
}sayHello()方法都被正常调用。 1.4、使用 AnnotationConfigApplicationContext 注册 AppContext 类的两种方法 1.4.1、 配置类的注册方式是将其传递给 AnnotationConfigApplicationContext 构造函数
public static void main(String[] args) {// Configuration注解的spring容器加载方式用AnnotationConfigApplicationContext替换ClassPathXmlApplicationContextApplicationContext context new AnnotationConfigApplicationContext(TestConfiguration.class);//获取beanTestBean tb (TestBean) context.getBean(testBean);tb.sayHello();}1.4.2、 AnnotationConfigApplicationContext 的register 方法传入配置类来注册配置类
public static void main(String[] args) {ApplicationContext ctx new AnnotationConfigApplicationContext();ctx.register(AppContext.class)
}1.5、配置Web应用程序(web.xml中配置AnnotationConfigApplicationContext) 过去您通常要利用 XmlWebApplicationContext 上下文来配置 Spring Web 应用程序即在 Web 部署描述符文件 web.xml 中指定外部 XML 上下文文件的路径。XMLWebApplicationContext 是 Web 应用程序使用的默认上下文类。以下代码描述了 web.xml 中指向将由 ContextLoaderListener 监听器类载入的外部 XML 上下文文件的元素。
web-appcontext-paramparam-namecontextConfigLocation/param-nameparam-value/WEB-INF/applicationContext.xml/param-value/context-paramlistenerlistener-classorg.springframework.web.context.ContextLoaderListener/listener-class/listenerservletservlet-namesampleServlet/servlet-nameservlet-classorg.springframework.web.servlet.DispatcherServlet/servlet-class/servlet...
/web-app现在您要将 web.xml 中的上述代码更改为使用 AnnotationConfigApplicationContext 类。切记XmlWebApplicationContext 是 Spring 为 Web 应用程序使用的默认上下文实现因此您永远不必在您的web.xml 文件中显式指定这个上下文类。现在您将使用基于 Java 的配置因此在配置 Web 应用程序时需要在web.xml 文件中指定 AnnotationConfigApplicationContext 类。上述代码将修改如下
web-appcontext-paramparam-namecontextClass/param-nameparam-valueorg.springframework.web.context.support.AnnotationConfigWebApplicationContext/param-value/context-paramcontext-paramparam-namecontextConfigLocation/param-nameparam-valuedemo.AppContext/param-value/context-paramlistenerlistener-classorg.springframework.web.context.ContextLoaderListener/listener-class/listenerservletservlet-namesampleServlet/servlet-nameservlet-classorg.springframework.web.servlet.DispatcherServlet/servlet-classinit-paramparam-namecontextClass/param-nameparam-valueorg.springframework.web.context.support.AnnotationConfigWebApplicationContext/param-value/init-param/servlet...
/web-app以上修改后的 web.xml 现在定义了 AnnotationConfigWebApplicationContext 上下文类并将其作为上下文参数和 servlet 元素的一部分。上下文配置位置现在指向 AppContext 配置类。这非常简单。下一节将演示 bean 的生命周期回调和范围的实现。
1.6、Configuation总结 Configuation等价于
Bean等价于
ComponentScan等价于context:component-scan base-package“com.dxz.demo”/
二、组合多个配置类
2.1、在configuration中引入spring的xml配置文件
package com.dxz.demo.configuration2;import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.ImportResource;Configuration
ImportResource(classpath:applicationContext-configuration.xml)
public class WebConfig {
}package com.dxz.demo.configuration2;public class TestBean2 {private String username;private String url;private String password;public void sayHello() {System.out.println(TestBean2 sayHello...);}public String toString() {return TestBean2 username: this.username ,url: this.url ,password: this.password;}public void start() {System.out.println(TestBean2 初始化。。。);}public void cleanUp() {System.out.println(TestBean2 销毁。。。);}
}package com.dxz.demo.configuration2;import org.springframework.context.ApplicationContext;
import org.springframework.context.annotation.AnnotationConfigApplicationContext;public class TestMain2 {public static void main(String[] args) {// Configuration注解的spring容器加载方式用AnnotationConfigApplicationContext替换ClassPathXmlApplicationContextApplicationContext context new AnnotationConfigApplicationContext(WebConfig.class);// 如果加载spring-context.xml文件// ApplicationContext context new// ClassPathXmlApplicationContext(spring-context.xml);// 获取beanTestBean2 tb (TestBean2) context.getBean(testBean2);tb.sayHello();}
}2.2、在configuration中引入其它注解配置
package com.dxz.demo.configuration2;import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Import;
import org.springframework.context.annotation.ImportResource;import com.dxz.demo.configuration.TestConfiguration;Configuration
ImportResource(classpath:applicationContext-configuration.xml)
Import(TestConfiguration.class)
public class WebConfig {
}package com.dxz.demo.configuration2;import org.springframework.context.ApplicationContext;
import org.springframework.context.annotation.AnnotationConfigApplicationContext;import com.dxz.demo.configuration.TestBean;public class TestMain2 {public static void main(String[] args) {// Configuration注解的spring容器加载方式用AnnotationConfigApplicationContext替换ClassPathXmlApplicationContextApplicationContext context new AnnotationConfigApplicationContext(WebConfig.class);// 如果加载spring-context.xml文件// ApplicationContext context new// ClassPathXmlApplicationContext(spring-context.xml);// 获取beanTestBean2 tb2 (TestBean2) context.getBean(testBean2);tb2.sayHello();TestBean tb (TestBean) context.getBean(testBean);tb.sayHello();}
}2.3、configuration嵌套嵌套的Configuration必须是静态类 通过配置类嵌套的配置类达到组合多个配置类的目的。但注意内部类必须是静态类。
上代码
package com.dxz.demo.configuration3;import org.springframework.stereotype.Component;Component
public class TestBean {private String username;private String url;private String password;public void sayHello() {System.out.println(TestBean sayHello...);}public String toString() {return username: this.username ,url: this.url ,password: this.password;}public void start() {System.out.println(TestBean start);}public void cleanUp() {System.out.println(TestBean destory);}
}package com.dxz.demo.configuration3;public class DataSource {private String dbUser;private String dbPass;public String getDbUser() {return dbUser;}public void setDbUser(String dbUser) {this.dbUser dbUser;}public String getDbPass() {return dbPass;}public void setDbPass(String dbPass) {this.dbPass dbPass;}Overridepublic String toString() {return DataSource [dbUser dbUser , dbPass dbPass ];}
}package com.dxz.demo.configuration3;import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.Configuration;Configuration
ComponentScan(basePackages com.dxz.demo.configuration3)
public class TestConfiguration {public TestConfiguration() {System.out.println(TestConfiguration容器启动初始化。。。);}Configurationstatic class DatabaseConfig {BeanDataSource dataSource() {return new DataSource();}}
}package com.dxz.demo.configuration3;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ClassPathXmlApplicationContextsApplicationContext context new AnnotationConfigApplicationContext(TestConfiguration.class);//beanTestBean tb (TestBean) context.getBean(testBean);tb.sayHello();DataSource ds (DataSource) context.getBean(dataSource);System.out.println(ds);}
}3、EnableXXX注解 配合Configuration使用包括 EnableAsync, EnableScheduling, EnableTransactionManagement, EnableAspectJAutoProxy, EnableWebMvc。
EnableAspectJAutoProxy—《spring AOP 之Aspect注解》
EnableScheduling–《Spring 3.1新特性之二Enable*注解的源码,spring源码分析之定时任务Scheduled注解》
4、Profile逻辑组配置 见《Spring的PropertySource EnvironmentPropertySourcePropertySourcesPlaceholderConfigurerValue配合使用》
5、使用外部变量 1、PropertySource Environment通过PropertySource注解将properties配置文件中的值存储到Spring的 Environment中Environment接口提供方法去读取配置文件中的值参数是properties文件中定义的key值。 2、PropertySourcePropertySourcesPlaceholderConfigurerValue
