Spring Boot 学习起步 六、SpringApplication

SpringApplication

spring boot通过调用SpringApplication.run启动应用.

//Application.java
package demo;

import org.springframework.boot.SpringApplication;

public class Application {

    public static void main(String[] args) {
        SpringApplication.run(ApplicationConfig.class, args);
    }

}

runa方法可以接受多个Java Configuration(@Configuration)作为入参

//AppConfig.java
package demo;

import org.springframework.beans.factory.annotation.Value;
import org.springframework.boot.autoconfigure.EnableAutoConfiguration;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.filter.CharacterEncodingFilter;
import org.springframework.web.servlet.DispatcherServlet;

@Configuration
@ComponentScan
@EnableAutoConfiguration
public class AppConfig {
    @Value("${characterEncoding}")
    String characterEncoding;

    @Bean
    public DispatcherServlet dispatcherServlet() {
        return new DispatcherServlet();
    }

    @Bean
    public CharacterEncodingFilter characterEncodingFilter() {
        CharacterEncodingFilter filter = new CharacterEncodingFilter();
        filter.setEncoding(characterEncoding);
        filter.setForceEncoding(true);
        return filter;
    }
}

#application.properties
characterEncoding = UTF-8

• 上面的AppConfig声明了2个bean,一个DispatcherServlet,一个CharacterEncodingFilter,characterEncodingFilter从配置文件中读取编码作为参数;

• 实际开发中可以根据项目需要定义任意多个bean,方法名会作为beanname,返回类型作为beantype;

• 也可以通过如下方式对bean进行定制:

  @Bean(name="xxx")
  @Scope(ConfigurableBeanFactory.SCOPE_PROTOTYPE)
  public Object foo(){
      return new Object();
  }

• 定制banner
  可以通过如下方式禁用banner的显示

  public static void main(String[] args) {
  SpringApplication app = new SpringApplication(MySpringConfiguration.class);
  app.setShowBanner(false);
  app.run(args);
  }

  也可以通过在classpath下添加banner.txt或者在配置文件中指定 banner.location,实现banner的定制.