Inline Field#equals check

README.md

@@ -166,3 +166,9 @@ decrease. (There are exceptions to this rule, e.g. when more code is deleted tha
 [sonarcloud-measure-maintainability]: https://sonarcloud.io/component_measures?id=tech.picnic.jolo%3Ajolo&metric=Maintainability
 [travisci-badge]: https://travis-ci.org/PicnicSupermarket/jolo.svg?branch=master
 [travisci-builds]: https://travis-ci.org/PicnicSupermarket/jolo
+
+## todo
+- make Loader implement Collector
+  - test against WMS Insight (locally)
+- Implement Copyable to replace prototype pattern or use immutables
+- Adopt Java modules

src/main/java/tech/picnic/jolo/Entity.java

@@ -2,7 +2,6 @@
 
 import static java.util.Arrays.stream;
 import static java.util.stream.Stream.concat;
-import static tech.picnic.jolo.Util.equalFieldNames;
 import static tech.picnic.jolo.Util.validate;
 
 import java.util.Arrays;
@@ -95,7 +94,9 @@ public String toString() {
    * the constructor with the extra argument is used to bring it into Java land.
    */
   public Entity<T, R> withExtraFields(Field<?>... extraFields) {
-    fields = concat(stream(fields), stream(extraFields)).toArray(Field<?>[]::new);
+    fields =
+        concat(stream(fields), stream(extraFields).filter(Objects::nonNull))
+            .toArray(Field<?>[]::new);
     return this;
   }
 
@@ -129,7 +130,9 @@ T load(Record record) {
      * record contains FOO.ID=1 and BAR.X=1, then without this measure, BAR.X would be used
      * instead of FOO.X.
      */
-    return record.into(resultFields).into(type);
+    T result = record.into(resultFields).into(type);
+    Objects.requireNonNull(result);
+    return result;
   }
 
   /**
@@ -157,8 +160,7 @@ private void check(Record record) {
           primaryKey.equals(record.field(primaryKey)),
           "Primary key column %s not found in result record",
           primaryKey);
-      resultFields =
-          stream(fields).filter(f -> equalFieldNames(f, record.field(f))).toArray(Field<?>[]::new);
+      resultFields = stream(fields).filter(f -> f.equals(record.field(f))).toArray(Field<?>[]::new);
     }
   }
 }

src/main/java/tech/picnic/jolo/ObjectGraph.java

@@ -39,7 +39,6 @@ final class ObjectGraph {
    * same entity and with the same ID already exists, the given object is ignored.
    */
   <E> void add(Entity<? extends E, ?> entity, long id, E object) {
-    requireNonNull(object);
     if (!entityAndIdToObject.contains(entity, id)) {
       entityAndIdToObject.put(entity, id, object);
     }

src/main/java/tech/picnic/jolo/Util.java

@@ -44,16 +44,6 @@ static <L extends Record, R extends Record> Optional<TableField<?, Long>> getOpt
     return Optional.of(getKey(from, keys.get(0).getFields(), "foreign"));
   }
 
-  static boolean equalFieldNames(@Nullable Field<?> left, @Nullable Field<?> right) {
-    if (left == null) {
-      return right == null;
-    }
-    if (right == null) {
-      return false;
-    }
-    return left.equals(right);
-  }
-
   @FormatMethod
   static void validate(boolean condition, String message, @Nullable Object... args) {
     if (!condition) {