SpringBoot之自定义Banner详解

 https://www.bootschool.net/ascii http://www.network-science.de/ascii/ http://patorjk.com/software/taag/ http://www.degraeve.com/img2txt.php

 public static void main(String[] args) { SpringApplication springApplication = new SpringApplication(Application.class); //开启Banner打印方式(OFF：关闭，CONSOLE：控制台输出，LOG：日志输出) springApplication.setBannerMode(Mode.LOG); springApplication.run(args); } 

 private Banner printBanner(ConfigurableEnvironment environment) { //是否开启Banner模式 if (this.bannerMode == Mode.OFF) { return null; } else { ResourceLoader resourceLoader = this.resourceLoader != null ? this.resourceLoader : new DefaultResourceLoader((ClassLoader)null); SpringApplicationBannerPrinter bannerPrinter = new SpringApplicationBannerPrinter((ResourceLoader)resourceLoader, this.banner); return this.bannerMode == Mode.LOG ? bannerPrinter.print(environment, this.mainApplicationClass, logger) : bannerPrinter.print(environment, this.mainApplicationClass, System.out); } } 

 Banner print(Environment environment, Class sourceClass, Log logger) { //调用getBanner()方法 Banner banner = this.getBanner(environment); try { logger.info(this.createStringFromBanner(banner, environment, sourceClass)); } catch (UnsupportedEncodingException var6) { logger.warn("Failed to create String for banner", var6); } return new SpringApplicationBannerPrinter.PrintedBanner(banner, sourceClass); } 

 private Banner getBanner(Environment environment) { SpringApplicationBannerPrinter.Banners banners = new SpringApplicationBannerPrinter.Banners(); //先获取image类型的banner banners.addIfNotNull(this.getImageBanner(environment)); //在获取text类型的banner banners.addIfNotNull(this.getTextBanner(environment)); if (banners.hasAtLeastOneBanner()) { // 如果至少有一个，则返回 // Banners 也实现了 Banner 接口，运用了组合模式，实际上可同时打印图片和文本 banner。 return banners; } else { // 返回自定义的banner(this.fallbackBanner) 或者 springboot默认的banner(DEFAULT_BANNER) // 默认的banner类：SpringBootBanner。 // 自定义的banner：需要我们仿照SpringBootBanner去自定义一个类 //this.fallbackBanner: 表示自定义的banner，此参数可在springboot启动类的main方法中设置,后续会介绍 //   public static void main(String[] args) { //        SpringApplication springApplication = new SpringApplication(Application.class); //        springApplication.setBanner(new MyBanner());//自定义的banner //        springApplication.run(args); //   } return this.fallbackBanner != null ? this.fallbackBanner : DEFAULT_BANNER; } } 

 //获取Text类型的banner private Banner getTextBanner(Environment environment) { //先从spring.banner.location路径中去取，如果没有，默认banner.txt String location = environment.getProperty("spring.banner.location", "banner.txt"); Resource resource = this.resourceLoader.getResource(location); try { if (resource.exists() && !resource.getURL().toExternalForm().contains("liquibase-core")) { return new ResourceBanner(resource); } } catch (IOException var5) {} return null; } //获取image类型的banner private Banner getImageBanner(Environment environment) { String location = environment.getProperty("spring.banner.image.location"); if (StringUtils.hasLength(location)) { Resource resource = this.resourceLoader.getResource(location); return resource.exists() ? new ImageBanner(resource) : null; } else { String[] var3 = IMAGE_EXTENSION; int var4 = var3.length; for(int var5 = 0; var5 < var4; ++var5) { String ext = var3[var5]; Resource resource = this.resourceLoader.getResource("banner." + ext); if (resource.exists()) { return new ImageBanner(resource); } } return null; } } 

 spring.banner.location=classpath:banner1.png-600 spring.banner.image.margin=2 spring.banner.image.height=76 spring.banner.charset=UTF-8 spring.banner.image.invert=false spring.banner.image.location=banner1.png-600 spring.main.banner-mode=console spring.main.show-banner=true 

 import org.springframework.boot.Banner; import org.springframework.boot.ansi.AnsiColor; import org.springframework.boot.ansi.AnsiOutput; import org.springframework.boot.ansi.AnsiStyle; import org.springframework.core.env.Environment; import java.io.PrintStream; /** 自定义banner类 * @author hb * @date 2021-09-09 10:39 */ public class MyBanner implements Banner { private static final String[] BANNER = new String[]{"", "  .   ____          _            __ _ _", " /\\\\ / ___'_ __ _ _(_)_ __  __ _ \\ \\ \\ \\", "( ( )\\___ | '_ | '_| | '_ \\/ _` | \\ \\ \\ \\", " \\\\/  ___)| |_)| | | | | || (_| |  ) ) ) )", "  '  |____| .__|_| |_|_| |_\\__, | / / / /", " =========|_|==============|___/=/_/_/_/"}; public MyBanner() { } @Override public void printBanner(Environment environment, Class sourceClass, PrintStream out) { String[] bannerArray = BANNER; int bannerLength = bannerArray.length; for(int i = 0; i <bannerLength; ++i) { String line = bannerArray[i]; out.println(line); } out.println(AnsiOutput.toString(new Object[]{AnsiColor.GREEN, " :: Spring Boot :: ", AnsiColor.DEFAULT,  AnsiStyle.FAINT})); out.println(); } } 

 @SpringBootApplication public class Application extends SpringBootServletInitializer { public static void main(String[] args) { SpringApplication springApplication = new SpringApplication(Application.class); //添加自定义banner springApplication.setBanner(new MyBanner()); springApplication.run(args); } } 

 AnsiColor： 用来设定字符的前景色 AnsiBackground： 用来设定字符的背景色 AnsiStyle： 用来控制加粗、斜体、下划线等等。 

 ${application.version}   与 MANIFEST.MF文件中相同的版本号，比如1.5.4.RELEASE ${application.formatted-version}   格式化过的版本号就是加个v然后用括号包起来，比如(v1.5.4.RELEASE) ${application.title} ${spring-boot.version} Spring Boot的版本 ${spring-boot.formatted-version} 格式化过的版本