Object instead of procedural utility class – example

OpenLMIS · Nov 21, 2017 · b5223be · b5223be
1 parent 6f1e373
commit b5223be
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Showing 3 changed files with 15 additions and 9 deletions.
diff --git a/...a/org/openlmis/cce/util/StringHelper.java → ...g/openlmis/cce/util/LowerCaseStrings.java b/...a/org/openlmis/cce/util/StringHelper.java → ...g/openlmis/cce/util/LowerCaseStrings.java
@@ -15,18 +15,25 @@
 
 package org.openlmis.cce.util;
 
+import java.util.Collection;
 import java.util.List;
 import java.util.stream.Collectors;
 
-public class StringHelper {
+public class LowerCaseStrings {
+
+  private final List<String> strings;
 
   /**
    * Make every string in given list lowerCase.
    */
-  public static List<String> lowerCase(List<String> strings) {
-    return strings.stream()
+  public LowerCaseStrings(Collection<String> strings) {
+    this.strings =  strings.stream()
         .map(String::toLowerCase)
         .collect(Collectors.toList());
   }
 
+  public List<String> asList() {
+    return strings;
+  }
+
 }
diff --git a/src/main/java/org/openlmis/cce/web/validator/CsvHeaderValidator.java b/src/main/java/org/openlmis/cce/web/validator/CsvHeaderValidator.java
@@ -18,14 +18,13 @@
 import static org.openlmis.cce.i18n.CsvUploadMessageKeys.ERROR_UPLOAD_HEADER_INVALID;
 import static org.openlmis.cce.i18n.CsvUploadMessageKeys.ERROR_UPLOAD_HEADER_MISSING;
 import static org.openlmis.cce.i18n.CsvUploadMessageKeys.ERROR_UPLOAD_MISSING_MANDATORY_COLUMNS;
-import static org.openlmis.cce.util.StringHelper.lowerCase;
 
 import org.apache.commons.collections.ListUtils;
 import org.openlmis.cce.exception.ValidationMessageException;
+import org.openlmis.cce.util.LowerCaseStrings;
 import org.openlmis.cce.web.csv.model.ModelClass;
 import org.openlmis.cce.web.csv.model.ModelField;
 import org.springframework.stereotype.Component;
-
 import java.util.List;
 import java.util.stream.Collectors;
 
@@ -38,7 +37,7 @@ public class CsvHeaderValidator {
   public void validateHeaders(List<String> headers, ModelClass<?> modelClass,
                               boolean acceptExtraHeaders) {
     validateNullHeaders(headers);
-    List<String> lowerCaseHeaders = lowerCase(headers);
+    List<String> lowerCaseHeaders = new LowerCaseStrings(headers).asList();
     if (!acceptExtraHeaders) {
       validateInvalidHeaders(lowerCaseHeaders, modelClass);
     }
@@ -64,7 +63,7 @@ private void validateMandatoryFields(List<String> headers, ModelClass modelClass
 
   private void validateInvalidHeaders(List<String> headers, ModelClass modelClass) {
     List<String> fieldNames = getAllImportedFieldNames(modelClass);
-    List invalidHeaders = ListUtils.subtract(headers, lowerCase(fieldNames));
+    List invalidHeaders = ListUtils.subtract(headers, new LowerCaseStrings(fieldNames).asList());
     if (!invalidHeaders.isEmpty()) {
       throw new ValidationMessageException(ERROR_UPLOAD_HEADER_INVALID, invalidHeaders.toString());
     }

diff --git a/...g/openlmis/cce/util/StringHelperTest.java → ...enlmis/cce/util/LowerCaseStringsTest.java b/...g/openlmis/cce/util/StringHelperTest.java → ...enlmis/cce/util/LowerCaseStringsTest.java
@@ -21,14 +21,14 @@
 import java.util.Arrays;
 import java.util.List;
 
-public class StringHelperTest {
+public class LowerCaseStringsTest {
 
   private static final String STRING_A = "StringA";
   private static final String STRING_B = "StringB";
 
   @Test
   public void shouldLowerCaseAllStrings() {
-    List<String> strings = StringHelper.lowerCase(Arrays.asList(STRING_A, STRING_B));
+    List<String> strings = new LowerCaseStrings(Arrays.asList(STRING_A, STRING_B)).asList();
     assertEquals(STRING_A.toLowerCase(), strings.get(0));
     assertEquals(STRING_B.toLowerCase(), strings.get(1));
   }