Spring Boot Devtools：检测自动重启并应用配置

1 回答

• 0

  这是一个想法：

  它's confusing to explain, but you'将看到下面的代码 . 当Spring-Boot在其依赖项中以 devtools 开始时，它首先启动，然后立即重新启动第一次通过 devtools . 您可以动态添加命令行参数来跟踪重新启动并更改 devtools 重新启动时使用的Spring配置文件：

  @SpringBootApplication
  public class App {
      public static void main(String[] args)
              throws ParseException, IOException, NoSuchFieldException, SecurityException, IllegalArgumentException, IllegalAccessException {
  
          String profile = "";
  
          //(1) Very first time - Spring Boot doesn't really load, it only kick start devtool then restarts.
          if (args.length == 0) {
              args = new String[] { "spring-boot-loaded" };
              profile = "no-devtools-yet";
          } 
  
          //(2) The first time the application loads with devtools
          else if (args.length == 1 && args[0].equals("spring-boot-loaded")) {
              args = new String[] { "spring-boot-loaded", "devtools-loaded" };
              profile = "devtools";
              Field argsField = Restarter.class.getDeclaredField("args");
              argsField.setAccessible(true);
              argsField.set(Restarter.getInstance(), args);
          } 
  
          //(3) This is the first restart - You don't want to re-initialized the database here
          else {
              profile = "devtools-reloaded";
          }
  
          new SpringApplicationBuilder() //
                  .sources(App.class)//
                  .profiles(profile) //
                  .run(args);
      }
  }
  

  粗略的部分是 Restarter 保留原始参数（在本例中为"no-devtools-yet"） . 因此，当 devtools 首次启动时，您需要替换 Restarter 的内部参数

  回复于 2024-05-02T06:02:24+08:00