Spring boot injects configuration properties into the Bean class

I. Use of @ConfigurationProperties annotations

Look at the configuration file, my configuration is in Yaml format:

// file application.ymlmy:  servers:    - dev.bar.com    - foo.bar.com - jiaobuchong.com

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Now I'm going to inject the above configuration properties into a Java bean class, looking at the Code:

Import org.springframework.boot.context.properties.ConfigurationProperties;Import org.springframework.stereotype.Component;import java.util.ArrayList; import java.util.List; /** * File:MyConfig.java * Created by Jiaobuchong on 12/29/15. */ @Component //do not add this annotation, the use of @autowired can not be injected into the @ Configurationproperties (prefix =  "my") //the prefix in the configuration file public class  Myconfig {private list<string> servers = new ArrayList <String> (); public list<string> getservers () { return this.servers;}       

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Write a controller below to Test:

/** * file: Hellocontroller * Created by Jiaobuchong on 2015/12/4. */ @RequestMapping ( "/test")  @RestController public class hellocontroller { @Autowired Span class= "hljs-keyword" >private myconfig myconfig;  @RequestMapping ( "/config")  Public Object getconfig () {return myconfig.getservers ();}}  

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Run Application.java's Main method below to See:

@Configuration//a class is a configuration class, spring boot automatically loads this class-related feature when it sweeps to this annotation, such as the configuration< on the class when configuring AOP and interceptors as described in the previous article Span class= "hljs-annotation" > @EnableAutoConfiguration //enable automatic configuration of the framework to be able to conduct the configuration, To boot and run the application, automatically load the configuration according to the imported Starter-pom  @ComponentScan // Scan component @ComponentScan (value = "com.spriboot.controller") Configure the path of the scan component public class application { Public static void main (String[] Args) {//start the spring boot project's unique portal springapplication app = new Springapplication (application.class); App.setbannermode (Banner.Mode.OFF); App.run (args); }

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In the address bar of the browser, type:
Localhost:8080/test/config get:
["dev.bar.com", "foo.bar.com", "jiaobuchong.com"]

Ii. @ConfigurationProperties and @enableconfigurationproperties annotations used together

The general steps for configuring with YAML in spring boot are,
1. YAML configuration file, Here are the assumptions:

my:  webserver:    #HTTP 监听端口    port: 80    #嵌入Web服务器的线程池配置    threadPool:      maxThreads: 100 minThreads: 8 idleTimeout: 60000

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2.

File Mywebserverconfigurationproperties.javaimport org.springframework.boot.context.properties.ConfigurationProperties; @ConfigurationProperties (prefix ="my.webserver")PublicClass Mywebserverconfigurationproperties {Privateint port;Private ThreadPool ThreadPool;PublicIntGetport () {Return port; }PublicvoidSetport (int Port) {This.port = port; }Public ThreadPoolGetthreadpool () {Return threadPool; }PublicvoidSetthreadpool (ThreadPool ThreadPool) {This.threadpool = threadPool; }PublicStaticClass ThreadPool {Privateint maxthreads;Privateint minthreads;Privateint idleTimeout;PublicIntGetidletimeout () {Return idleTimeout; }PublicvoidSetidletimeout (int IdleTimeout) {this.idletimeout = idleTimeout;} public int getMaxThreads () {return maxthreads; } public void setMaxThreads (int maxthreads) {this.maxthreads = maxthreads;} public int getminthreads () {return minthreads; } public void setMinThreads (int minthreads) {this.minthreads = minthreads;}}}     

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3.

File:MyWebServerConfiguration.javaimport org.springframework.context.annotation.Configuration; import org.springframework.boot.context.properties.enableconfigurationproperties;< Span class= "hljs-annotation" > @Configuration  @EnableConfigurationProperties ( Mywebserverconfigurationproperties.class) public class mywebserverconfiguration { @Autowired private mywebserverconfigurationproperties properties; /** * Below you can refer to the configuration in the Mywebserverconfigurationproperties class */void setmyconfig () {String port = properties.getport (); Span class= "hljs-comment" >//.....} }

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The @enableconfigurationproperties Annotation is automatically applied to your project so, any beans Annotated with @ConfigurationProperties'll be configured from the environment Properties. This is the style of the configuration works particularly well with the Springapplication external YAML Configuration. (quoted from spring Boot official Manual)

Iii. @Bean Configuring Third-party components (third-party Configuration)

Create a bean class:

File Threadpoolbean.java/** * Created by Jiaobuchong on 1/4/16. */PublicClassThreadpoolbean {Privateint maxthreads;Privateint minthreads;Privateint idleTimeout;PublicIntGetMaxThreads () {Return maxthreads; }PublicvoidSetMaxThreads (int Maxthreads) {this.maxthreads = maxthreads;} public int getMinThreads () {return minthreads; } public void setMinThreads (int minthreads) {this.minthreads = minthreads;} public int getidletimeout () {return idleTimeout; } public void setIdleTimeout (int idleTimeout) {this.idletimeout = idleTimeout;}}    

Refer to the configuration classes written in the second part of the previous section: Mywebserverconfiguration.java and mywebserverconfigurationproperties.java, and YAML configuration files, Now modify the Mywebserverconfiguration.java class:

Import com.jiaobuchong.springboot.domain.ThreadPoolBean;Import org.springframework.beans.factory.annotation.Autowired;Import org.springframework.boot.context.properties.EnableConfigurationProperties;Import org.springframework.context.annotation.Bean;Import org.springframework.context.annotation.Configuration;/** * Created by Jiaobuchong on 1/4/16. */@ConfigurationThis is a configuration class, similar to the @service, @Component Effect. Spring will scan to this class, @Bean will take effect, register Threadpoolbean This return value class in the spring context@EnableConfigurationProperties (mywebserverconfigurationproperties. Class)With this annotation, the configuration of this class is mywebserverconfigurationproperties to the context, and the @ used in this classautowiredannotation injection to take effectPublicClassmywebserverconfiguration { @SuppressWarnings ( "springjavaautowiringinspection") Span class= "hljs-comment" >//add This annotation so that the IDE does not report: Could not autowire  @Autowired private mywebserverconfigurationproperties properties;  @Bean //@Bean annotations on a method, the return value is an instance of a class and declares the return value (returning an Object) is a bean in the spring context public threadpoolbean getthreadbean () { Mywebserverconfigurationproperties.threadpool ThreadPool = Properties.getthreadpool (); Threadpoolbean Threadpoolbean = new threadpoolbean (); threadpoolbean.setidletimeout ( Threadpool.getidletimeout ()); Threadpoolbean.setmaxthreads (threadpool.getmaxthreads ()); Threadpoolbean.setminthreads (threadpool.getminthreads ()); return threadpoolbean;}          

The class identified by the @configuration annotation, typically as a configuration class, is similar to an XML file, which indicates that bean metadata is configured in that class, which acts like a application-context.xml configuration file in spring, and @ A bean tag, which resembles a bean instance declared in the XML file.

Write a controller test:

Import com.jiaobuchong.springboot.domain.ThreadPoolBean;Import org.springframework.beans.factory.annotation.Autowired;import org.springframework.web.bind.annotation.RequestMapping; import org.springframework.web.bind.annotation.RestController; /** * Created by Jiaobuchong on 2015/12/4. */ @RequestMapping ( "/first")  @RestController  Public class hellocontroller { @Autowired private threadpoolbean threadpoolbean;  @RequestMapping ("/testbean ") public Object getthreadbean () {return threadpoolbean;}}    

Run Application.java's main method,
In the browser, type: Http://localhost:8080/first/testbean
The resulting return value is:
{"maxthreads": +, "minthreads": 8, "idleTimeout": 60000}

http://blog.csdn.net/jiaobuchong/article/details/50442709

Spring boot injects configuration properties into the Bean class