#1956 - Add SqlQuery - mapTo( RowMapper) ... to deprecate findOne(RowMapper)

src/main/java/io/ebean/RowMapper.java

@@ -18,7 +18,7 @@ import java.sql.SQLException;
  * <pre>{@code
  *
  *    //
- *    // A mapper from ResultSet into our CustomerDto bean
+ *    // Map from ResultSet to CustomerDto bean
  *    //
  *    class CustomerMapper implements RowMapper<CustomerDto> {
  *
@@ -42,7 +42,8 @@ import java.sql.SQLException;
  *
  *  CustomerDto rob = DB.sqlQuery(sql)
  *    .setParameter(1, "Rob")
- *    .findOne(CUSTOMER_MAPPER);
+ *    .mapTo(CUSTOMER_MAPPER)
+ *    .findOne();
  *
  *
  * }</pre>

src/main/java/io/ebean/SqlQuery.java

@@ -75,17 +75,15 @@ public interface SqlQuery extends Serializable {
   SqlRow findOne();
 
   /**
-   * Execute the query returning a single result using the mapper.
-   *
-   * @param mapper Used to map each ResultSet row into the result object.
+   * Deprecated migrate to use {@link #mapTo(RowMapper)}
    */
+  @Deprecated
   <T> T findOne(RowMapper<T> mapper);
 
   /**
-   * Execute the query returning a list using the mapper.
-   *
-   * @param mapper Used to map each ResultSet row into the result object.
+   * Deprecated migrate to use {@link #mapTo(RowMapper)}
    */
+  @Deprecated
   <T> List<T> findList(RowMapper<T> mapper);
 
   /**
@@ -158,28 +156,14 @@ public interface SqlQuery extends Serializable {
   Long findSingleLong();
 
   /**
-   * Execute the query returning a list of scalar attribute values.
-   *
+   * Deprecated - migrate to <code>.mapToScalar(Long.class).findList()</code>.
    * <pre>{@code
    *
-   *   String sql =
-   *   " select (unit_price * order_qty) " +
-   *   " from o_order_detail " +
-   *   " where unit_price > ? " +
-   *   " order by (unit_price * order_qty) desc";
-   *
-   *   List<BigDecimal> lineAmounts =
-   *     DB.sqlQuery(sql)
-   *       .setParameter(42)
-   *       .findSingleAttributeList(BigDecimal.class);
-   *
-   * }</pre>
-   *
-   * <p>
-   * The attributeType can be any scalar type that Ebean supports (includes javax time types, Joda types etc).
-   *
-   * @param attributeType The type of the returned value
+   *    .mapToScalar(Long.class)
+   *    .findList();
+   * }
    */
+  @Deprecated
   <T> List<T> findSingleAttributeList(Class<T> attributeType);
 
   /**
@@ -312,14 +296,23 @@ public interface SqlQuery extends Serializable {
    * @param attributeType The type the result is returned as
    * @return The query to execute via findOne() findList() etc
    */
-  <T> ScalarQuery<T> mapToScalar(Class<T> attributeType);
+  <T> TypeQuery<T> mapToScalar(Class<T> attributeType);
+
+  /**
+   * Use a RowMapper to map the result to beans.
+   *
+   * @param mapper Maps rows to beans
+   * @param <T>    The type of beans mapped to
+   * @return The query to execute by findOne() findList() etc
+   */
+  <T> TypeQuery<T> mapTo(RowMapper<T> mapper);
 
   /**
    * Query mapping to single scalar values.
    *
    * @param <T> The type of the scalar values
    */
-  interface ScalarQuery<T> {
+  interface TypeQuery<T> {
 
     /**
      * Return the single value.

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

@@ -208,12 +208,25 @@ public class DefaultRelationalQuery implements SpiSqlQuery {
     return query;
   }
 
+  <T> T mapperFindOne(RowMapper<T> mapper) {
+    return server.findOneMapper(this, mapper);
+  }
+
+  <T> List<T> mapperFindList(RowMapper<T> mapper) {
+    return server.findListMapper(this, mapper);
+  }
+
   @Override
-  public <T> ScalarQuery<T> mapToScalar(Class<T> attributeType) {
+  public <T> TypeQuery<T> mapToScalar(Class<T> attributeType) {
     return new Scalar(attributeType);
   }
 
-  private class Scalar<T> implements SqlQuery.ScalarQuery<T> {
+  @Override
+  public <T> TypeQuery<T> mapTo(RowMapper<T> mapper) {
+    return new Mapper(mapper);
+  }
+
+  private class Scalar<T> implements SqlQuery.TypeQuery<T> {
 
     private final Class<T> type;
 
@@ -236,4 +249,28 @@ public class DefaultRelationalQuery implements SpiSqlQuery {
       return findSingleAttributeList(type);
     }
   }
+
+  private class Mapper<T> implements SqlQuery.TypeQuery<T> {
+
+    private final RowMapper<T> mapper;
+
+    Mapper(RowMapper<T> mapper) {
+      this.mapper = mapper;
+    }
+
+    @Override
+    public T findOne() {
+      return mapperFindOne(mapper);
+    }
+
+    @Override
+    public Optional<T> findOneOrEmpty() {
+      return Optional.ofNullable(findOne());
+    }
+
+    @Override
+    public List<T> findList() {
+      return mapperFindList(mapper);
+    }
+  }
 }