From afa4233b40c7f992df7c17c88ca51a5adb91af46 Mon Sep 17 00:00:00 2001
From: Lukas Eder <lukas.eder@datageekery.com>
Date: Wed, 26 Feb 2025 14:35:02 +0100
Subject: [PATCH] [jOOQ/jOOQ#18059] ArrayStoreException when using
 Converter<T[][], U[][]> with empty arrays

---
 .../src/main/java/org/jooq/ArrayConverter.java | 12 ++++++++----
 jOOQ/src/main/java/org/jooq/impl/Convert.java  | 18 ++++++++++++++++--
 2 files changed, 24 insertions(+), 6 deletions(-)

diff --git a/jOOQ/src/main/java/org/jooq/ArrayConverter.java b/jOOQ/src/main/java/org/jooq/ArrayConverter.java
index a70ffeaf56..d665eac86b 100644
--- a/jOOQ/src/main/java/org/jooq/ArrayConverter.java
+++ b/jOOQ/src/main/java/org/jooq/ArrayConverter.java
@@ -38,9 +38,10 @@
 package org.jooq;
 
 import static org.jooq.impl.Internal.arrayType;
+import static org.jooq.tools.reflect.Reflect.wrapper;
 
 import org.jooq.impl.AbstractContextConverter;
-import org.jooq.tools.Convert;
+import org.jooq.impl.Internal;
 
 /**
  * A {@link Converter} that can convert arrays based on a delegate converter
@@ -54,7 +55,10 @@ final class ArrayConverter<T, U> extends AbstractContextConverter<T[], U[]> {
     final ContextConverter<U, T> inverse;
 
     public ArrayConverter(ContextConverter<T, U> converter) {
-        super(arrayType(converter.fromType()), arrayType(converter.toType()));
+
+        // [#18059] Work with wrapper types, as we cannot represent Converter<int, U>,
+        //          so we shouldn't work with Converter<int[], U[]> either
+        super(arrayType(wrapper(converter.fromType())), arrayType(wrapper(converter.toType())));
 
         this.converter = converter;
         this.inverse = Converters.inverse(converter);
@@ -72,11 +76,11 @@ final class ArrayConverter<T, U> extends AbstractContextConverter<T[], U[]> {
 
     @Override
     public final U[] from(T[] t, ConverterContext scope) {
-        return Convert.convertArray(t, converter);
+        return Internal.convertArray(t, converter);
     }
 
     @Override
     public final T[] to(U[] t, ConverterContext scope) {
-        return Convert.convertArray(t, inverse);
+        return Internal.convertArray(t, inverse);
     }
 }
diff --git a/jOOQ/src/main/java/org/jooq/impl/Convert.java b/jOOQ/src/main/java/org/jooq/impl/Convert.java
index c0ef4304f7..e4c86e264a 100644
--- a/jOOQ/src/main/java/org/jooq/impl/Convert.java
+++ b/jOOQ/src/main/java/org/jooq/impl/Convert.java
@@ -137,6 +137,8 @@ import org.jooq.types.YearToSecond;
 import org.jooq.util.postgres.PostgresUtils;
 import org.jooq.util.xml.jaxb.InformationSchema;
 
+import org.jetbrains.annotations.NotNull;
+
 import jakarta.xml.bind.JAXB;
 
 /**
@@ -406,7 +408,7 @@ final class Convert {
     static final Object convertArray(Object[] from, Class<?> toClass) throws DataTypeException {
         if (from == null)
             return null;
-        else if (!toClass.isArray())
+        else if (!equalArrayDegree(from.getClass(), toClass))
             return convertArray(from, arrayType(toClass));
         else if (toClass == from.getClass())
             return from;
@@ -492,7 +494,19 @@ final class Convert {
         }
     }
 
-    static final <U> U[] convertCollection(Collection from, Class<? extends U[]> to){
+    private static boolean equalArrayDegree(Class<?> c1, Class<?> c2) {
+        Class<?> ct1 = c1.getComponentType();
+        Class<?> ct2 = c2.getComponentType();
+
+        if (ct1 == null && ct2 == null)
+            return true;
+        else if (ct1 == null || ct2 == null)
+            return false;
+        else
+            return equalArrayDegree(ct1, ct2);
+    }
+
+    static final <U> U[] convertCollection(Collection from, Class<? extends U[]> to) {
         return new ConvertAll<U[]>(to).from(from, converterContext());
     }