From 25e42c2737eb007d4bd735977ad3dc9eb89adcf9 Mon Sep 17 00:00:00 2001
From: Lukas Eder <lukas.eder@gmail.com>
Date: Wed, 16 Feb 2022 16:39:31 +0100
Subject: [PATCH] [jOOQ/jOOQ#12515] Support for RowN.mapping(Function<? super
 Object[], ? extends U>)

---
 jOOQ/src/main/java/org/jooq/RowN.java         | 25 +++++++++++++++++++
 .../src/main/java/org/jooq/impl/RowImplN.java | 15 +++++++++++
 2 files changed, 40 insertions(+)

diff --git a/jOOQ/src/main/java/org/jooq/RowN.java b/jOOQ/src/main/java/org/jooq/RowN.java
index c230e3a4b3..0ae4d37b6b 100644
--- a/jOOQ/src/main/java/org/jooq/RowN.java
+++ b/jOOQ/src/main/java/org/jooq/RowN.java
@@ -85,6 +85,31 @@ import org.jetbrains.annotations.NotNull;
  */
 public interface RowN extends Row, SelectField<Record> {
 
+    // ------------------------------------------------------------------------
+    // Mapping convenience methods
+    // ------------------------------------------------------------------------
+
+    /**
+     * A convenience method to define a local {@link Record} to custom type
+     * {@link RecordMapper} that can be used when projecting {@link Row} types
+     * in <code>SELECT</code> or <code>RETURNING</code> clauses.
+     * <p>
+     * Unlike {@link #mapping(Class, Function)}, this method attempts to work
+     * without an explicit {@link Class} reference for the underlying
+     * {@link Converter#toType()}, e.g. when nesting rows in arrays, the class
+     * literal is required for reflective array creation.
+     */
+    @NotNull
+    <U> SelectField<U> mapping(Function<? super Object[], ? extends U> function);
+
+    /**
+     * A convenience method to define a local {@link Record} to custom type
+     * {@link RecordMapper} that can be used when projecting {@link Row} types in
+     * <code>SELECT</code> or <code>RETURNING</code> clauses.
+     */
+    @NotNull
+    <U> SelectField<U> mapping(Class<U> uType, Function<? super Object[], ? extends U> function);
+
     // ------------------------------------------------------------------------
     // Generic comparison predicates
     // ------------------------------------------------------------------------
diff --git a/jOOQ/src/main/java/org/jooq/impl/RowImplN.java b/jOOQ/src/main/java/org/jooq/impl/RowImplN.java
index 699c65ebe9..e785110609 100644
--- a/jOOQ/src/main/java/org/jooq/impl/RowImplN.java
+++ b/jOOQ/src/main/java/org/jooq/impl/RowImplN.java
@@ -41,6 +41,7 @@ import static org.jooq.impl.DSL.row;
 
 import java.util.Arrays;
 import java.util.Collection;
+import java.util.function.Function;
 
 import org.jooq.BetweenAndStepN;
 import org.jooq.Comparator;
@@ -75,6 +76,20 @@ final class RowImplN extends AbstractRow<Record> implements RowN {
         super((FieldsImpl) fields);
     }
 
+    // ------------------------------------------------------------------------
+    // Mapping convenience methods
+    // ------------------------------------------------------------------------
+
+    @Override
+    public final <U> SelectField<U> mapping(Function<? super Object[], ? extends U> function) {
+        return rf().convertFrom(r -> r == null ? null : function.apply(r.intoArray()));
+    }
+
+    @Override
+    public final <U> SelectField<U> mapping(Class<U> uType, Function<? super Object[], ? extends U> function) {
+        return rf().convertFrom(uType, r -> r == null ? null : function.apply(r.intoArray()));
+    }
+
     // ------------------------------------------------------------------------
     // Generic comparison predicates
     // ------------------------------------------------------------------------