Basic Configuration
- Enable Component Scan Configuration
java class profile mode package Com.springapp.mvc.application; import org.springframework.context.annotation.componentscan;import org.springframework.context.annotation.configuration; /** * created by xuc on 2018/1/7. * Configuration Class */@ComponentScan (basepackages = {"COM.SPRINGAPP.MVC"}) @ configurationpublic class application {} Note: Here @configuration for declaring the class as a profile class, @ Componentscan to enable scanning for claims, if the underlying package properties are not configured, the current package is scanned by default, otherwise the package XML file for the scan base package definition is configured <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 " 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 "> <context:component-scan base-package=" Com.springapp.mvc "/> <bean class=" Org.springframework.web.servlet.view.InternalResourceViewResolver "> <property name= "prefix" value= "/web-inf/pages/"/> <property name= "suffix" value= ". jsp"/> </bean></beans>
In most cases we use component scans to load beans, but sometimes when using a third-party framework, some configuration classes need to be specified, in which case the manual configuration is more appropriate Java class assembly mode package com.springapp.mvc.application; import com.springapp.mvc.easyBean.Braves;import com.springapp.mvc.easyBean.Sword;import org.springframework.context.annotation.bean;import org.springframework.context.annotation.componentscan; import org.springframework.context.annotation.configuration; /** * created by xuc on 2018/1/7. * Configuration Class */@ComponentScan (basepackages = {"Com.springapp.mvc" }) @Configurationpublic class Application { @Bean (name = "Braves") Public braves braves () { return new braves (Sword ()); } @Bean public braves braves1 () { BRaves braves = new braves (); Braves.setsword (Sword ()); return braves; } @Bean Public sword sword () { Return new sword (); }} Note : The configuration file class is declared here first, and then by @bean annotations on the method, spring will know that the method will return a bean and register it in the spring context. @Bean Note If you configure the Name property, the Bean's ID is the value, otherwise the default is the same as the method name. The Braves () and Braves1 () methods implement constructor injection and set mode injection   ; xml file Configuration Method <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 " 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 "> <context:component-scan base-package= "Com.springapp.mvc"/> <bean class= " Com.springapp.mvc.easyBean.Sword " id=" Sword "></bean> <bean class=" Com.springapp.mvc.easyBean.Braves " id=" Braves "> <constructor-arg ref=" Sword "></constructor-arg> </bean> <bean class=" Com.springapp.mvc.easyBean.Braves " id=" braves1 "> <property name=" Sword " ref= "Sword" ></property> </bean> <bean class= " Org.springframework.web.servlet.view.InternalResourceViewResolver "> <property name= "prefix" value= "/web-inf/pages/"/> <property name= "suffix" value= ". jsp"/> </bean></beans> braves beans and braves1 beans respectively implement constructor injection and set mode injection.
- Java class and XML file hybrid configuration (single or multiple)
java class configuration package com.springapp.mvc.application; import com.springapp.mvc.easyBean.Sword;import org.springframework.context.annotation.*; /** * created by xuc on 2018/1/7. * Configuration Class */@ComponentScan ( basepackages = {"Com.springapp.mvc"}) @Configuration @import (application1.class) @ImportResource (" Classpath:mvc-dispatcher-servlet.xml ") public class application { @Bean Public sword sword () { Return new sword (); }} Note: Here @import annotations for the import configuration Java class, @ImportResource annotations for the import configuration XML file, where you can configure multiple, through the well-spaced nbsp XML file Configuration <beans xmlns= "Http://www.springframework.org/schema/beans" &NBSP;XMLNS: Xsi= "Http://www.w3.org/2001/XMLSchema-instance" xmlns:context= "http://www.springFramework.org/schema/context " 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 "> <context:component-scan base-package=" Com.springapp.mvc "/> <import resource= "Mvc-dispatcher-servlet1.xml" ></import> < bean class= "Com.springapp.mvc.application.Application" ></bean> <bean class= "Org.springframework.web.servlet.view.InternalResourceViewResolver" > < Property name= "prefix" value= "/web-inf/pages/"/> <property name= " Suffix " value=". jsp "/> </bean></beans> Conditional configuration
- spring profile for cross-environment configuration
1. Configure profile bean & nbsp java class configuration Package com.springapp.mvc.application; import ... /** * created by xuc on 2018/1/7. * Configuration Class */@ComponentScan (basepackages = {" Com.springapp.mvc "}) @Configurationpublic class Application { @Bean Public braves braves (iarms arms) { return new braves (arms); } @Bean @Profile ("Dev") Public sword sword () { Return new sword (); } @Bean @Profile ("test") Public machete machete () { Return new machete (); }} NOTE: Use @profile annotations to declare which environment the bean belongs to (commonFor database connection operations) xml file Configuration <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 " 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 "> <context:component-scan base-package= "Com.springapp.mvc"/> <beans profile= "Dev" > <bean class= "Com.springapp.mvc.easyBean.Sword" ></bean> </beans> <beans profile= "test" > <BEAN&NBSP;CLass= "Com.springapp.mvc.easyBean.Machete" ></bean> </beans> <beans > <bean class= " Org.springframework.web.servlet.view.InternalResourceViewResolver "> < Property name= "prefix" value= "/web-inf/pages/"/> <property name= "suffix" value= ". JSP"/> </bean> </beans></ beans> 2. Activate Spring profile<web-app version = "2.4" xmlns= "HTTP://JAVA.SUN.COM/XML/NS/J2EE" xmlns:xsi= "http://www.w3.org/2001/ Xmlschema-instance " xsi:schemalocation=" http://java.sun.com/xml/ns/j2ee http:// Java.sun.com/xml/ns/j2ee/web-app_2_4.xsd "> <display-name>Spring MVC application</display-name> &NBSP;≪context-param> <param-name>spring.profiles.default</param-name> <param-value>dev</param-value> </context-param> <servlet> <servlet-name>mvc-dispatcher</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> & nbsp <load-on-startup>1</load-on-startup> </servlet> < servlet-mapping> <servlet-name>mvc-dispatcher</servlet-name> <url-pattern>/</url-pattern> &NBSP;</SERVLET-MAPPING></WEB-APP≫ Note: In Web Apps, just configure Spring.profiles.default or Spring.profiles.active, the former is the default which is active 3. Test &NBSP ; in the case of "dev", there will only be sword beans, and using the machete bean will report the Class no exception!
- Condition Implementing a conditional registration bean
Define a class that implements the condition interface, implements the matches () method, and verifies the validation in the method Packag E com.springapp.mvc.application; import org.springframework.context.annotation.condition;import org.springframework.context.annotation.ConditionContext;import org.springframework.core.env.environment;import org.springframework.core.type.annotatedtypemetadata; /** * Created by xuc on 2018/1/7. * condition determine if bean is creating */public class AppCondition implements Condition { @Override Public boolean matches (conditioncontext conditioncontext, annotatedtypemetadata Annotatedtypemetadata) { environment environment = Conditioncontext.getenvironment (); if (environment.acceptsprofiles ("dev") | | environment.acceptsprofiles ("test")) { &NBSP; return true; } return false; &N Bsp }} NOTE: @profile Note The value check is implemented through condition, Profilecondition for its implementation class as follows: @Retention (retentionpolicy.runtime) @Target ({elementtype.type, Elementtype.method}) @Documented @conditional (profilecondition.class) public @interface profile { /** * the set of profiles for which the annotated component should be registered. */ String[] value (); } class ProfileCondition implements Condition { @Override public boolean matches (conditioncontext context, annotatedtypemetadata Metadata) { if (context.getenvironment () != null) {   multivaluemap<string, object> attrs = metadata.getallannotationattributes ( Profile.class.getName ()); if (attrs != null) { for (Object value : attrs.get ("value")) { if (Context.getenvironment () Acceptsprofiles (((string[)) value)) { return true; } } Return fals e; } } return true; } }
- Bean Injection ambiguity problem
1. Add @primary annotation to the bean to be injected, declaring that the bean is a priority injection package com.springapp.mvc.application; import com.springapp.mvc.easybean.braves;import com.springapp.mvc.easybean.iarms;import com.springapp.mvc.easybean.machete;import com.springapp.mvc.easybean.sword;import org.springframework.context.annotation.*; /** * created by xuc on 2018/1/7. * Configuration Class */@ComponentScan (basepackages = {"Com.springapp.mvc"}) @Configurationpublic class Application { @Bean @Conditional (appcondition.class) public braves braves (iarms arms) { return new braves (arms); } @Bean @Profile ("Dev") & nbsp @Primary Public sword sword () { Return new sword (); }&NBSp @Bean @Profile ("test") Public machete machete () { Return new machete (); }} &NBSP;&NBSP ; 2. Add @qualifier annotations to injected beans package com.springapp.mvc.application; import com.springapp.mvc.easybean.braves;import com.springapp.mvc.easybean.iarms;import com.springapp.mvc.easybean.machete;import Com.springapp.mvc.easybean.sword;import org.springframework.beans.factory.annotation.qualifier;import org.springframework.context.annotation.*; /** * Created by xuc on 2018/1/7. * Configuration Class */@ComponentScan (basepackages = {"COM.SPRINGAPP.MVC"}) @ configurationpublic class application { @Bean @Qualifier ("sword") Public braves braves (IARMS&NBsp;arms) { return new braves (arms); } @Bean @ Profile ("Dev") Public sword sword () { return new Sword (); } @Bean @Profile ("test") Public machete machete () { Return new machete (); }} &N Bsp NOTE: If there are multiple (that is, multiple priority) here, you can customize the annotations
| Scope |
Describe |
| Singleton |
This scope restricts the definition of the bean to a single instance of each Spring IoC container (the default). |
| Prototype |
This scope restricts the definition of a single bean to any number of object instances. |
| Request |
This scope restricts the bean's definition to an HTTP request. Valid only in the context of Web-aware Spring ApplicationContext. |
| Session |
This scope restricts the bean's definition to an HTTP session. Valid only in the context of Web-aware Spring ApplicationContext. |
| Global-session |
This scope restricts the bean's definition to a global HTTP session. Valid only in the context of Web-aware Spring ApplicationContext. |
package com.springapp.mvc.application; import com.springapp.mvc.easybean.braves;import com.springapp.mvc.easyBean.IArms;import com.springapp.mvc.easyBean.Machete;import Com.springapp.mvc.easybean.sword;import org.springframework.beans.factory.annotation.qualifier;import org.springframework.context.annotation.*;import Org.springframework.web.context.webapplicationcontext; /** * created by xuc on 2018/1/7. * Configuration Class */@ComponentScan (basepackages = {"COM.SPRINGAPP.MVC"}) @ configurationpublic class application { @Bean public braves Braves (iarms arms) { return new braves (arms); } @ bean @Profile ("Dev") @Scope (value = webapplicationcontext.scope_global_session , PROXYMODE&NBSP;=&NBSP;SCOPEDPROXYMODE.target_class) Public sword sword () { return new Sword (); } @Bean @Profile ("test") Public machete machete () { Return new machete (); }} &N Bsp Note: The Sword bean is redefined here through @scope annotations as a session-level scope, because sword is loaded as a priority when using Braves, and the Proxymode claims proxy class, is to inject the session-level sword into a single-class Braves by the form of deferred injection. If this is the interface: "Proxymode = scopedproxymode.interfaces" github Address: Https://github.com/xc83415134/spring_bean_demo environment: Idea, Spring4.0 reference: "Spring Combat"
Spring Use Tour (i)----Bean Assembly
