list of chemical sources doesn't contain null anymore

annotation/src/main/java/lcsb/mapviewer/annotation/data/Chemical.java

@@ -291,13 +291,17 @@ public class Chemical implements Serializable, TargettingStructure {
 
 	}
 
-	@Override
-	public Collection<MiriamData> getSources() {
-		List<MiriamData> sources = new ArrayList<>();
-		sources.add(getCasID());
-		sources.add(getChemicalId());
-		return sources;
-	}
+  @Override
+  public Collection<MiriamData> getSources() {
+    List<MiriamData> sources = new ArrayList<>();
+    if (getCasID() != null) {
+      sources.add(getCasID());
+    }
+    if (getChemicalId() != null) {
+      sources.add(getChemicalId());
+    }
+    return sources;
+  }
 
 	@Override
 	public Collection<Target> getTargets() {

service/src/main/java/lcsb/mapviewer/services/search/db/DbSearchService.java

@@ -44,5 +44,4 @@ public abstract class DbSearchService {
 		}
 		
 	}
-
 }

service/src/test/java/lcsb/mapviewer/services/search/db/AllSearchDbTests.java

@@ -10,8 +10,9 @@ import lcsb.mapviewer.services.search.db.mirna.MiRNAServiceTest;
 
 @RunWith(Suite.class)
 @SuiteClasses({ AllSearchDrugTests.class, //
-		ChemicalServiceTest.class, //
-		MiRNAServiceTest.class, //
+    ChemicalServiceTest.class, //
+    DbSearchServiceTest.class, //
+    MiRNAServiceTest.class, //
 })
 public class AllSearchDbTests {
 

service/src/test/java/lcsb/mapviewer/services/search/db/DbSearchServiceTest.java

+package lcsb.mapviewer.services.search.db;
+
+import org.junit.Test;
+import org.mockito.Mockito;
+
+import lcsb.mapviewer.annotation.data.Chemical;
+
+public class DbSearchServiceTest {
+
+  @Test
+  public void testCacheMiriamData() throws Exception {
+    Chemical chemical = new Chemical();
+    DbSearchService service = Mockito.mock(DbSearchService.class, Mockito.CALLS_REAL_METHODS);
+    service.cacheMiriamData(chemical);
+
+  }
+
+}