官方文档：JetBrains插件开发生命周期

1.IDEA预加载

<extensions defaultExtensionNs="com.intellij">
  <preloadingActivity implementation="com.example.CatPreloadingActivity"/>
</extensions>

2.IDEA启动时

<extensions defaultExtensionNs="com.intellij">
    <startupActivity implementation="com.example.plugin_demo.MyApplicationComponent"/>
</extensions>

public class MyApplicationComponent implements StartupActivity {
    @Override
    public void runActivity(@NotNull Project project) {

    }
}

3.IDEA启动后

<extensions defaultExtensionNs="com.intellij">
  <postStartupActivity implementation="com.example.CatStartupActivity"/>
</extensions>

public class MyApplicationComponent extends ShelveChangesManager.PostStartupActivity {
    @Override
    public void runActivity(@NotNull Project project) {
        System.out.println("启动成");
        firstPluginTest1.notify(project,"启动成功", NotificationType.INFORMATION);
    }
}