returned value should be a list not a string

rest-api/src/main/java/lcsb/mapviewer/api/projects/overlays/OverlayRestImpl.java

@@ -102,12 +102,13 @@ public class OverlayRestImpl extends BaseRestImpl {
     return result;
   }
 
-  private String getDeprecatedColumns(Layout overlay) {
+  private List<String> getDeprecatedColumns(Layout overlay) {
     try {
-      String result = "";
+      List<String> result = new ArrayList<>();
       for (ColorSchemaColumn column : new ColorSchemaReader().getDeprecatedColumns(overlay)) {
-        result += column.name() + ",";
+        result.add(column.name());
       }
+      logger.debug(result);
       return result;
     } catch (IOException | InvalidColorSchemaException e) {
       throw new InvalidStateException(e);

web/src/test/java/lcsb/mapviewer/web/OverlayControllerIntegrationTest.java

 package lcsb.mapviewer.web;
 
-import static org.junit.Assert.*;
+import static org.junit.Assert.assertEquals;
 import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.*;
 import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.status;
 
@@ -1051,12 +1051,11 @@ public class OverlayControllerIntegrationTest extends ControllerIntegrationTest
     String response = mockMvc.perform(request)
         .andExpect(status().is2xxSuccessful())
         .andReturn().getResponse().getContentAsString();
-    String deprecatedColumns = new JsonParser()
+    int deprecatedColumns = new JsonParser()
         .parse(response)
-        .getAsJsonObject().get("deprecatedColumns").getAsString();
+        .getAsJsonObject().get("deprecatedColumns").getAsJsonArray().size();
 
-    assertNotNull(deprecatedColumns);
-    assertFalse(deprecatedColumns.isEmpty());
+    assertEquals(2, deprecatedColumns);
   }
 
 }