Use type-safe constants in ExitStatus#isRunning

Signed-off-by: sjiwon <sjiwon4491@gmail.com>

Author: sjiwon

spring-batch-core/src/main/java/org/springframework/batch/core/ExitStatus.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2006-2023 the original author or authors.
+ * Copyright 2006-2025 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -29,6 +29,7 @@
  *
  * @author Dave Syer
  * @author Mahmoud Ben Hassine
+ * @author JiWon Seo
  *
  */
 public class ExitStatus implements Serializable, Comparable<ExitStatus> {
@@ -231,7 +232,7 @@ public ExitStatus replaceExitCode(String code) {
 	 * @return {@code true} if the exit code is {@code EXECUTING} or {@code UNKNOWN}.
 	 */
 	public boolean isRunning() {
-		return "EXECUTING".equals(this.exitCode) || "UNKNOWN".equals(this.exitCode);
+		return EXECUTING.exitCode.equals(this.exitCode) || UNKNOWN.exitCode.equals(this.exitCode);
 	}
 
 	/**

spring-batch-core/src/test/java/org/springframework/batch/core/ExitStatusTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2006-2024 the original author or authors.
+ * Copyright 2006-2025 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -33,6 +33,7 @@
 /**
  * @author Dave Syer
  * @author Mahmoud Ben Hassine
+ * @author JiWon Seo
  *
  */
 class ExitStatusTests {
@@ -153,7 +154,7 @@ void testAddExitDescription() {
 	}
 
 	@Test
-	void testAddExitDescriptionWIthStacktrace() {
+	void testAddExitDescriptionWithStacktrace() {
 		ExitStatus status = ExitStatus.EXECUTING.addExitDescription(new RuntimeException("Foo"));
 		assertNotSame(ExitStatus.EXECUTING, status);
 		String description = status.getExitDescription();
@@ -182,8 +183,15 @@ void testAddExitCodeWithDescription() {
 	}
 
 	@Test
-	void testUnknownIsRunning() {
+	void testIsRunning() {
+		// running statuses
+		assertTrue(ExitStatus.EXECUTING.isRunning());
 		assertTrue(ExitStatus.UNKNOWN.isRunning());
+		// non running statuses
+		assertFalse(ExitStatus.COMPLETED.isRunning());
+		assertFalse(ExitStatus.FAILED.isRunning());
+		assertFalse(ExitStatus.STOPPED.isRunning());
+		assertFalse(ExitStatus.NOOP.isRunning());
 	}
 
 	@Test