Add StringUtility#camelCaseToUpperCase

eclipse-scout · Oct 8, 2021 · 865c2d1 · 865c2d1
1 parent f4e7ec4
commit 865c2d1
Show file tree

Hide file tree

Showing 2 changed files with 40 additions and 0 deletions.
diff --git a/....rt.platform.test/src/test/java/org/eclipse/scout/rt/platform/util/StringUtilityTest.java b/....rt.platform.test/src/test/java/org/eclipse/scout/rt/platform/util/StringUtilityTest.java
@@ -737,6 +737,19 @@ public void testLowercaseFirst() {
     assertEquals("fOO BAR", StringUtility.lowercaseFirst("FOO BAR"));
   }
 
+  @Test
+  public void testCamelCaseToUpperCase() {
+    assertEquals(null, StringUtility.camelCaseToUpperCase(null));
+    assertEquals("", StringUtility.camelCaseToUpperCase(""));
+    assertEquals(" ", StringUtility.camelCaseToUpperCase(" "));
+    assertEquals("A", StringUtility.camelCaseToUpperCase("A"));
+    assertEquals("B", StringUtility.camelCaseToUpperCase("b"));
+    assertEquals("FOO", StringUtility.camelCaseToUpperCase("Foo"));
+    assertEquals("FOO", StringUtility.camelCaseToUpperCase("foo"));
+    assertEquals("FOO_BAR", StringUtility.camelCaseToUpperCase("FooBar"));
+    assertEquals("FOO_BAR", StringUtility.camelCaseToUpperCase("fooBar"));
+  }
+
   @Test
   public void testRandomId() {
     assertNotNull(StringUtility.randomId());

diff --git a/...pse.scout.rt.platform/src/main/java/org/eclipse/scout/rt/platform/util/StringUtility.java b/...pse.scout.rt.platform/src/main/java/org/eclipse/scout/rt/platform/util/StringUtility.java
@@ -1147,6 +1147,33 @@ public static String uppercaseFirst(String s) {
     return s.substring(0, 1).toUpperCase() + s.substring(1);
   }
 
+  /**
+   * Transforms a camel case formatted string to upper case with underlines string.
+   * <p>
+   * Examples:
+   * <ul>
+   * <li>foo -> FOO
+   * <li>fooBar -> FOO_BAR
+   * <li>FooBar -> FOO_BAR
+   * </ul>
+   */
+  public static String camelCaseToUpperCase(String s) {
+    if (isNullOrEmpty(s)) {
+      return s;
+    }
+    int len = s.length();
+    StringBuilder builder = new StringBuilder(len);
+    builder.append(Character.toUpperCase(s.charAt(0)));
+    for (int i = 1; i < len; i++) {
+      char c = s.charAt(i);
+      if (Character.isUpperCase(c)) {
+        builder.append('_');
+      }
+      builder.append(Character.toUpperCase(c));
+    }
+    return builder.toString();
+  }
+
   /**
    * Null-safe version of {@link String#split(String)}.
    * <p>