#35 springboot: environment variables - command line

springboot/external/src/main/java/hello/CommandLineBean.java

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+package hello;
+
+import jakarta.annotation.PostConstruct;
+import lombok.RequiredArgsConstructor;
+import lombok.extern.slf4j.Slf4j;
+import org.springframework.boot.ApplicationArguments;
+import org.springframework.stereotype.Component;
+
+import java.util.List;
+import java.util.Set;
+
+@Slf4j
+@Component
+@RequiredArgsConstructor
+public class CommandLineBean {
+
+    private final ApplicationArguments arguments;
+
+    @PostConstruct
+    public void init() {
+        log.info("source {}", List.of(arguments.getSourceArgs()));
+        log.info("optionNames {}", arguments.getOptionNames());
+        Set<String> optionNames = arguments.getOptionNames();
+        optionNames.forEach(
+                optionName -> log.info("option args {}={}", optionName, arguments.getOptionValues(optionName))
+        );
+    }
+}

springboot/external/src/test/java/hello/external/CommandLineV1.java

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+package hello.external;
+
+import lombok.extern.slf4j.Slf4j;
+
+import java.util.Arrays;
+
+@Slf4j
+public class CommandLineV1 {
+
+    // dataA dataB
+    public static void main(String[] args) {
+        Arrays.stream(args).forEach(arg -> log.info("arg = {}", arg));
+    }
+}

springboot/external/src/test/java/hello/external/CommandLineV2.java

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+package hello.external;
+
+import lombok.extern.slf4j.Slf4j;
+import org.springframework.boot.DefaultApplicationArguments;
+
+import java.util.Arrays;
+import java.util.List;
+import java.util.Set;
+
+@Slf4j
+public class CommandLineV2 {
+
+    // --url=devdb --username=dev --password=1234 mode=on
+    public static void main(String[] args) {
+        Arrays.stream(args).forEach(arg -> log.info("arg = {}", arg));
+
+        DefaultApplicationArguments appArgs = new DefaultApplicationArguments(args);
+        log.info("SourceArgs = {}", List.of(appArgs.getSourceArgs()));
+        log.info("NonOptionsArgs = {}", appArgs.getNonOptionArgs());
+        log.info("OptionsNames = {}", appArgs.getOptionNames());
+
+        Set<String> optionNames = appArgs.getOptionNames();
+        optionNames.forEach(
+                optionName -> log.info("option arg {}={}", optionName, appArgs.getOptionValues(optionName))
+        );
+
+        List<String> url = appArgs.getOptionValues("url");
+        List<String> username = appArgs.getOptionValues("username");
+        List<String> password = appArgs.getOptionValues("password");
+        List<String> mode = appArgs.getOptionValues("mode");
+        log.info("url={}", url);
+        log.info("username={}", username);
+        log.info("password={}", password);
+        log.info("mode={}", mode);
+
+    }
+}