CommandLineRunner 接口可以實現當服務啟動時預先加載一些功能，比如參數預先加載等。當需要實現多個功能預先加載時，需要使用`@Order`來指定加載的順序。 ```java public @interface Order { int value() default 2147483647; //該值越小，越先被執行 } ``` 使用步驟如下： **1. 創建SpringBoot項目** **2. 創建三個類來實現CommandLineRunner接口** （1）CommandLineRunnerDriver1。 ```java import org.springframework.boot.CommandLineRunner; import org.springframework.core.annotation.Order; import org.springframework.stereotype.Component; @Component @Order(value = 1) public class CommandLineRunnerDriver1 implements CommandLineRunner { @Override public void run(String... args) throws Exception { System.out.println("CommandLineRunnerDriver1執行成功！"); } } ``` （2）CommandLineRunnerDriver2。 ```java import org.springframework.boot.CommandLineRunner; import org.springframework.core.annotation.Order; import org.springframework.stereotype.Component; @Component @Order(value = 2) public class CommandLineRunnerDriver2 implements CommandLineRunner { @Override public void run(String... args) throws Exception { System.out.println("CommandLineRunnerDriver2執行成功！"); } } ``` （3）CommandLineRunnerDriver3。 ```java import org.springframework.boot.CommandLineRunner; import org.springframework.core.annotation.Order; import org.springframework.stereotype.Component; @Component @Order(value = 3) public class CommandLineRunnerDriver3 implements CommandLineRunner { @Override public void run(String... args) throws Exception { System.out.println("CommandLineRunnerDriver3執行成功！"); } } ``` **3. 運行啟動類，預加載的順序如下** ``` CommandL ineRunnerDriver1執行成功! CommandL ineRunnerDriver2執行成功! CommandL ineRunnerDriver3執行成功! ```