#996 Add findOne() and findOneOrEmpty()

src/main/java/io/ebean/EbeanServer.java

@@ -14,6 +14,7 @@ import javax.persistence.PersistenceException;
 import java.util.Collection;
 import java.util.List;
 import java.util.Map;
+import java.util.Optional;
 import java.util.Set;
 import java.util.function.Consumer;
 import java.util.function.Predicate;
@@ -1066,7 +1067,7 @@ public interface EbeanServer {
    * This will throw a NonUniqueResultException if the query finds more than one result.
    * </p>
    * <p>
-   * Generally you are able to use {@link Query#findUnique()} rather than
+   * Generally you are able to use {@link Query#findOne()} rather than
    * explicitly calling this method. You could use this method if you wish to
    * explicitly control the transaction used for the query.
    * </p>
@@ -1076,7 +1077,22 @@ public interface EbeanServer {
    * @param transaction the transaction to use (can be null).
    * @return the list of fetched beans.
    * @throws NonUniqueResultException if more than one result was found
-   * @see Query#findUnique()
+   * @see Query#findOne()
+   */
+  @Nullable
+  <T> T findOne(Query<T> query, Transaction transaction);
+
+  /**
+   * Similar to findOne() but returns an Optional (rather than nullable).
+   */
+  <T> Optional<T> findOneOrEmpty(Query<T> query, Transaction transaction);
+
+  /**
+   * Synonym for findOne().
+   * <p>
+   * This proceeded findOne which was introduced to better match spring data.
+   * This will be deprecated at some future point.
+   * </p>
    */
   @Nullable
   <T> T findUnique(Query<T> query, Transaction transaction);

src/main/java/io/ebean/ExpressionList.java

@@ -12,6 +12,7 @@ import java.sql.Timestamp;
 import java.util.Collection;
 import java.util.List;
 import java.util.Map;
+import java.util.Optional;
 import java.util.Set;
 import java.util.function.Consumer;
 import java.util.function.Predicate;
@@ -266,6 +267,21 @@ public interface ExpressionList<T> {
    * @see Query#findUnique()
    */
   @Nullable
+  T findOne();
+
+  /**
+   * Execute the query returning an optional bean.
+   */
+  Optional<T> findOneOrEmpty();
+
+  /**
+   * Synonym for findOne().
+   * <p>
+   * This proceeded findOne which was introduced to better match spring data.
+   * This will be deprecated at some future point.
+   * </p>
+   */
+  @Nullable
   T findUnique();
 
   /**

src/main/java/io/ebean/Query.java

@@ -6,6 +6,7 @@ import javax.persistence.NonUniqueResultException;
 import java.sql.Timestamp;
 import java.util.List;
 import java.util.Map;
+import java.util.Optional;
 import java.util.Set;
 import java.util.function.Consumer;
 import java.util.function.Predicate;
@@ -854,6 +855,21 @@ public interface Query<T> {
    * @throws NonUniqueResultException if more than one result was found
    */
   @Nullable
+  T findOne();
+
+  /**
+   * Execute the query returning an optional bean.
+   */
+  Optional<T> findOneOrEmpty();
+
+  /**
+   * Synonym for findOne().
+   * <p>
+   * This proceeded findOne which was introduced to better match spring data.
+   * This will be deprecated at some future point.
+   * </p>
+   */
+  @Nullable
   T findUnique();
 
   /**

src/main/java/io/ebeaninternal/server/core/DefaultServer.java

@@ -104,6 +104,7 @@ import java.util.Collection;
 import java.util.Iterator;
 import java.util.List;
 import java.util.Map;
+import java.util.Optional;
 import java.util.Set;
 import java.util.concurrent.ConcurrentHashMap;
 import java.util.function.Consumer;
@@ -1175,6 +1176,16 @@ public final class DefaultServer implements SpiServer, SpiEbeanServer {
 
   @Override
   public <T> T findUnique(Query<T> query, Transaction transaction) {
+    return findOne(query, transaction);
+  }
+
+  @Override
+  public <T> Optional<T> findOneOrEmpty(Query<T> query, Transaction transaction) {
+    return Optional.ofNullable(findOne(query, transaction));
+  }
+
+  @Override
+  public <T> T findOne(Query<T> query, Transaction transaction) {
 
     SpiQuery<T> spiQuery = (SpiQuery<T>) query;
     spiQuery.checkIdEqualTo();

src/main/java/io/ebeaninternal/server/expression/DefaultExpressionList.java

@@ -34,6 +34,7 @@ import java.util.ArrayList;
 import java.util.Collection;
 import java.util.List;
 import java.util.Map;
+import java.util.Optional;
 import java.util.Set;
 import java.util.function.Consumer;
 import java.util.function.Predicate;
@@ -409,6 +410,16 @@ public class DefaultExpressionList<T> implements SpiExpressionList<T> {
     return query.findSingleAttributeList();
   }
 
+  @Override
+  public T findOne() {
+    return query.findOne();
+  }
+
+  @Override
+  public Optional<T> findOneOrEmpty() {
+    return query.findOneOrEmpty();
+  }
+
   @Override
   public T findUnique() {
     return query.findUnique();

src/main/java/io/ebeaninternal/server/expression/JunctionExpression.java

@@ -31,6 +31,7 @@ import java.sql.Timestamp;
 import java.util.Collection;
 import java.util.List;
 import java.util.Map;
+import java.util.Optional;
 import java.util.Set;
 import java.util.function.Consumer;
 import java.util.function.Predicate;
@@ -414,6 +415,16 @@ class JunctionExpression<T> implements SpiJunction<T>, SpiExpression, Expression
     return exprList.findSet();
   }
 
+  @Override
+  public T findOne() {
+    return exprList.findOne();
+  }
+
+  @Override
+  public Optional<T> findOneOrEmpty() {
+    return exprList.findOneOrEmpty();
+  }
+
   @Override
   public T findUnique() {
     return exprList.findUnique();

src/main/java/io/ebeaninternal/server/querydefn/DefaultOrmQuery.java

@@ -50,6 +50,7 @@ import java.util.HashMap;
 import java.util.Iterator;
 import java.util.List;
 import java.util.Map;
+import java.util.Optional;
 import java.util.Set;
 import java.util.function.Consumer;
 import java.util.function.Predicate;
@@ -1255,10 +1256,20 @@ public class DefaultOrmQuery<T> implements SpiQuery<T> {
   }
 
   @Override
-  public T findUnique() {
+  public T findOne() {
     return server.findUnique(this, null);
   }
 
+  @Override
+  public Optional<T> findOneOrEmpty() {
+    return server.findOneOrEmpty(this, null);
+  }
+
+  @Override
+  public T findUnique() {
+    return findOne();
+  }
+
   @Override
   public FutureIds<T> findFutureIds() {
     return server.findFutureIds(this, null);