fixes and formatting

Author: SarahGrand

core/model-api/src/main/java/org/eclipse/rdf4j/model/Literal.java

@@ -56,11 +56,12 @@ enum BaseDirection {
 			this.suffix = suffix;
 		}
 
+		@Override
 		public String toString() {
 			return suffix;
 		}
 
-		public static BaseDirection fromString(String dir) {
+		public static BaseDirection fromString(final String dir) {
 			if (dir == null || dir.isEmpty())
 				return NONE;
 			if (dir.equals(LTR_SUFFIX))

core/model-api/src/main/java/org/eclipse/rdf4j/model/base/AbstractValueFactory.java

@@ -154,6 +154,7 @@ public Literal createLiteral(String label, String language, Literal.BaseDirectio
 
 		Objects.requireNonNull(label, "null label");
 		Objects.requireNonNull(language, "null language");
+		Objects.requireNonNull(baseDirection, "null baseDirection");
 
 		if (language.isEmpty()) {
 			throw new IllegalArgumentException("empty language tag");

core/model/src/main/java/org/eclipse/rdf4j/model/impl/SimpleLiteral.java

@@ -177,6 +177,7 @@ protected void setLanguage(String language) {
 	}
 
 	protected void setBaseDirection(BaseDirection baseDirection) {
+		Objects.requireNonNull(baseDirection, "null baseDirection");
 		this.baseDirection = baseDirection;
 		if (this.baseDirection != BaseDirection.NONE) {
 			setDatatype(CoreDatatype.RDF.DIRLANGSTRING);

core/sail/elasticsearch-store/src/main/java/org/eclipse/rdf4j/sail/elasticsearchstore/ElasticsearchDataStructure.java

@@ -244,7 +244,8 @@ private QueryBuilder getQueryBuilder(Resource subject, IRI predicate, Value obje
 					boolQueryBuilder
 							.must(QueryBuilders.termQuery("object_Lang", ((Literal) object).getLanguage().get()));
 					boolQueryBuilder
-							.must(QueryBuilders.termQuery("object_LangDir", ((Literal) object).getBaseDirection().toString()));
+							.must(QueryBuilders.termQuery("object_LangDir",
+									((Literal) object).getBaseDirection().toString()));
 				}
 			}
 		}

core/sail/lmdb/src/main/java/org/eclipse/rdf4j/sail/lmdb/model/LmdbLiteral.java

@@ -11,6 +11,7 @@
 package org.eclipse.rdf4j.sail.lmdb.model;
 
 import java.io.ObjectStreamException;
+import java.util.Objects;
 import java.util.Optional;
 
 import org.eclipse.rdf4j.model.IRI;
@@ -90,6 +91,8 @@ public LmdbLiteral(ValueStoreRevision revision, String label, String lang, BaseD
 
 	public LmdbLiteral(ValueStoreRevision revision, String label, String language, BaseDirection baseDirection,
 			long internalID) {
+		Objects.requireNonNull(language, "null language");
+		Objects.requireNonNull(baseDirection, "null baseDirection");
 		this.label = label;
 		this.language = language;
 		this.baseDirection = baseDirection;