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tools/cldr/cldr-to-icu/src/main/java/org/unicode/icu/tool/cldrtoicu/ant/CleanOutputDirectoryTask.java

@@ -385,7 +385,7 @@ public static CleanOutputDirectoryTask fromXml(String fileName) {
 
             NodeList outputDirectories = root.getElementsByTagName("outputDirectories");
             if (outputDirectories.getLength() != 1) {
-                System.err.println("Only one <outputDirectories> element allowed and required");
+                System.err.println("Exactly one <outputDirectories> element allowed and required");
                 return null;
             }
             CleanOutputDirectoryTask cleaner = new CleanOutputDirectoryTask();