diff --git a/pom.xml b/pom.xml
index c133ca2b..0ffa0e97 100644
--- a/pom.xml
+++ b/pom.xml
@@ -78,6 +78,11 @@
       <artifactId>httpclient5</artifactId>
       <version>${httpclient5.version}</version>
     </dependency>
+    <dependency>
+      <groupId>commons-io</groupId>
+      <artifactId>commons-io</artifactId>
+      <version>${commons-io.version}</version>
+    </dependency>
     <dependency>
       <groupId>org.apache.commons</groupId>
       <artifactId>commons-lang3</artifactId>
@@ -94,11 +99,6 @@
       <version>${slf4j.version}</version>
       <scope>test</scope>
     </dependency>
-    <dependency>
-      <groupId>commons-io</groupId>
-      <artifactId>commons-io</artifactId>
-      <version>${commons-io.version}</version>
-    </dependency>
     <dependency>
       <groupId>org.apache.maven</groupId>
       <artifactId>maven-artifact</artifactId>
diff --git a/src/main/java/org/hisp/dhis/util/UidUtils.java b/src/main/java/org/hisp/dhis/util/UidUtils.java
index e3be0fbf..f6df815c 100644
--- a/src/main/java/org/hisp/dhis/util/UidUtils.java
+++ b/src/main/java/org/hisp/dhis/util/UidUtils.java
@@ -34,18 +34,17 @@
 
 @NoArgsConstructor(access = AccessLevel.PRIVATE)
 public class UidUtils {
-  private static final String letters = "abcdefghijklmnopqrstuvwxyz" + "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
+  private static final String ALPHABET = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ";
+  private static final String DIGITS = "0123456789";
+  private static final String ALLOWED_CHARS = ALPHABET + DIGITS;
 
-  private static final String ALLOWED_CHARS = "0123456789" + letters;
-
-  private static final int NUMBER_OF_CODEPOINTS = ALLOWED_CHARS.length();
+  private static final int CHAR_LENGTH = ALLOWED_CHARS.length();
+  private static final int UID_LENGTH = 11;
 
   private static final Pattern UID_PATTERN = Pattern.compile("^[a-zA-Z]{1}[a-zA-Z0-9]{10}$");
 
-  private static final int CODESIZE = 11;
-
   /**
-   * Generates a UID according to the following rules:
+   * Generates a UID according to the following rules.
    *
    * <ul>
    *   <li>Alphanumeric characters only.
@@ -53,10 +52,10 @@ public class UidUtils {
    *   <li>First character is alphabetic.
    * </ul>
    *
-   * @return a UID.
+   * @return a UID string.
    */
   public static String generateUid() {
-    return generateCode(CODESIZE);
+    return generateCode(UID_LENGTH);
   }
 
   /**
@@ -82,10 +81,10 @@ public static String generateCode(int codeSize) {
 
     // First char should be a letter
 
-    randomChars[0] = letters.charAt(r.nextInt(letters.length()));
+    randomChars[0] = ALPHABET.charAt(r.nextInt(ALPHABET.length()));
 
     for (int i = 1; i < codeSize; ++i) {
-      randomChars[i] = ALLOWED_CHARS.charAt(r.nextInt(NUMBER_OF_CODEPOINTS));
+      randomChars[i] = ALLOWED_CHARS.charAt(r.nextInt(CHAR_LENGTH));
     }
 
     return new String(randomChars);