Use interfaces when possible

Author: jeffgbutler

src/main/java/org/mybatis/dynamic/sql/select/AbstractHavingStarter.java

@@ -25,14 +25,14 @@
 import org.mybatis.dynamic.sql.SqlCriterion;
 import org.mybatis.dynamic.sql.VisitableCondition;
 
-public abstract class AbstractHavingStarter<F extends AbstractHavingFinisher<?>> {
+public interface AbstractHavingStarter<F extends AbstractHavingFinisher<?>> {
 
-    public <T> F having(BindableColumn<T> column, VisitableCondition<T> condition,
+    default <T> F having(BindableColumn<T> column, VisitableCondition<T> condition,
                         AndOrCriteriaGroup... subCriteria) {
         return having(column, condition, Arrays.asList(subCriteria));
     }
 
-    public <T> F having(BindableColumn<T> column, VisitableCondition<T> condition,
+    default <T> F having(BindableColumn<T> column, VisitableCondition<T> condition,
                         List<AndOrCriteriaGroup> subCriteria) {
         SqlCriterion sqlCriterion = ColumnAndConditionCriterion.withColumn(column)
                 .withCondition(condition)
@@ -42,11 +42,11 @@ public <T> F having(BindableColumn<T> column, VisitableCondition<T> condition,
         return initialize(sqlCriterion);
     }
 
-    public F having(SqlCriterion initialCriterion, AndOrCriteriaGroup... subCriteria) {
+    default F having(SqlCriterion initialCriterion, AndOrCriteriaGroup... subCriteria) {
         return having(initialCriterion, Arrays.asList(subCriteria));
     }
 
-    public F having(SqlCriterion initialCriterion, List<AndOrCriteriaGroup> subCriteria) {
+    default F having(SqlCriterion initialCriterion, List<AndOrCriteriaGroup> subCriteria) {
         SqlCriterion sqlCriterion = new CriteriaGroup.Builder()
                 .withInitialCriterion(initialCriterion)
                 .withSubCriteria(subCriteria)
@@ -55,9 +55,9 @@ public F having(SqlCriterion initialCriterion, List<AndOrCriteriaGroup> subCrite
         return initialize(sqlCriterion);
     }
 
-    protected abstract F having();
+    F having();
 
-    public F applyHaving(HavingApplier havingApplier) {
+    default F applyHaving(HavingApplier havingApplier) {
         F finisher = having();
         havingApplier.accept(finisher);
         return finisher;

src/main/java/org/mybatis/dynamic/sql/select/HavingDSL.java

@@ -17,11 +17,11 @@
 
 import org.mybatis.dynamic.sql.util.Buildable;
 
-public class HavingDSL extends AbstractHavingStarter<HavingDSL.StandaloneHavingFinisher> {
+public class HavingDSL implements AbstractHavingStarter<HavingDSL.StandaloneHavingFinisher> {
     private final StandaloneHavingFinisher havingFinisher = new StandaloneHavingFinisher();
 
     @Override
-    protected StandaloneHavingFinisher having() {
+    public StandaloneHavingFinisher having() {
         return havingFinisher;
     }
 

src/main/java/org/mybatis/dynamic/sql/select/QueryExpressionDSL.java

@@ -477,8 +477,8 @@ public SelectDSL<R> getSelectDSL() {
         }
     }
 
-    public class GroupByFinisher extends AbstractHavingStarter<QueryExpressionHavingBuilder>
-            implements Buildable<R>, SelectDSLOperations<R> {
+    public class GroupByFinisher implements AbstractHavingStarter<QueryExpressionHavingBuilder>,
+            Buildable<R>, SelectDSLOperations<R> {
         public SelectDSL<R> orderBy(SortSpecification... columns) {
             return orderBy(Arrays.asList(columns));
         }