From 8a76d8767e7ce63de965fe7d69d380fd6bc5749e Mon Sep 17 00:00:00 2001
From: Azhwani <13301425+azhwani@users.noreply.github.com>
Date: Sat, 21 Jan 2023 16:16:18 +0100
Subject: [PATCH] BAEL-6044: Fix the IllegalArgumentException: No enum const
 class (#13171)

---
 .../exception/noenumconst/Priority.java       | 13 +++++++
 .../exception/noenumconst/PriorityUtils.java  | 21 +++++++++++
 .../noenumconst/PriorityUtilsUnitTest.java    | 36 +++++++++++++++++++
 3 files changed, 70 insertions(+)
 create mode 100644 core-java-modules/core-java-exceptions-4/src/main/java/com/baeldung/exception/noenumconst/Priority.java
 create mode 100644 core-java-modules/core-java-exceptions-4/src/main/java/com/baeldung/exception/noenumconst/PriorityUtils.java
 create mode 100644 core-java-modules/core-java-exceptions-4/src/test/java/com/baeldung/exception/noenumconst/PriorityUtilsUnitTest.java

diff --git a/core-java-modules/core-java-exceptions-4/src/main/java/com/baeldung/exception/noenumconst/Priority.java b/core-java-modules/core-java-exceptions-4/src/main/java/com/baeldung/exception/noenumconst/Priority.java
new file mode 100644
index 0000000000..ff9591b1e0
--- /dev/null
+++ b/core-java-modules/core-java-exceptions-4/src/main/java/com/baeldung/exception/noenumconst/Priority.java
@@ -0,0 +1,13 @@
+package com.baeldung.exception.noenumconst;
+
+public enum Priority {
+
+    HIGH("High"), MEDIUM("Medium"), LOW("Low");
+
+    private String name;
+
+    Priority(String name) {
+        this.name = name;
+    }
+
+}
diff --git a/core-java-modules/core-java-exceptions-4/src/main/java/com/baeldung/exception/noenumconst/PriorityUtils.java b/core-java-modules/core-java-exceptions-4/src/main/java/com/baeldung/exception/noenumconst/PriorityUtils.java
new file mode 100644
index 0000000000..8d7004bf39
--- /dev/null
+++ b/core-java-modules/core-java-exceptions-4/src/main/java/com/baeldung/exception/noenumconst/PriorityUtils.java
@@ -0,0 +1,21 @@
+package com.baeldung.exception.noenumconst;
+
+public class PriorityUtils {
+
+    public static Priority getByName(String name) {
+        return Priority.valueOf(name);
+    }
+
+    public static Priority getByUpperCaseName(String name) {
+        if (name == null || name.isEmpty()) {
+            return null;
+        }
+
+        return Priority.valueOf(name.toUpperCase());
+    }
+
+    public static void main(String[] args) {
+        System.out.println(getByName("Low"));
+    }
+
+}
diff --git a/core-java-modules/core-java-exceptions-4/src/test/java/com/baeldung/exception/noenumconst/PriorityUtilsUnitTest.java b/core-java-modules/core-java-exceptions-4/src/test/java/com/baeldung/exception/noenumconst/PriorityUtilsUnitTest.java
new file mode 100644
index 0000000000..1ff9c49015
--- /dev/null
+++ b/core-java-modules/core-java-exceptions-4/src/test/java/com/baeldung/exception/noenumconst/PriorityUtilsUnitTest.java
@@ -0,0 +1,36 @@
+package com.baeldung.exception.noenumconst;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertNull;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+
+import org.junit.jupiter.api.Test;
+
+class PriorityUtilsUnitTest {
+
+    @Test
+    void givenCustomName_whenUsingGetByName_thenThrowIllegalArgumentException() {
+        assertThrows(IllegalArgumentException.class, () -> PriorityUtils.getByName("Low"));
+    }
+
+    @Test
+    void givenCustomName_whenUsingGetByUpperCaseName_thenReturnEnumConstant() {
+        assertEquals(Priority.HIGH, PriorityUtils.getByUpperCaseName("High"));
+    }
+
+    @Test
+    void givenInvalidCustomName_whenUsingGetByUpperCaseName_thenThrowIllegalArgumentException() {
+        assertThrows(IllegalArgumentException.class, () -> PriorityUtils.getByUpperCaseName("invalid"));
+    }
+
+    @Test
+    void givenEmptyName_whenUsingGetByUpperCaseName_thenReturnNull() {
+        assertNull(PriorityUtils.getByUpperCaseName(""));
+    }
+
+    @Test
+    void givenNull_whenUsingGetByUpperCaseName_thenReturnNull() {
+        assertNull(PriorityUtils.getByUpperCaseName(null));
+    }
+
+}