Visitor for {@link java.util.UUID} type. When it is created with logicalTypesEnabled enabled,

 * Avro schema is created with logical type uuid.

Author: MichalFoksa

avro/src/main/java/com/fasterxml/jackson/dataformat/avro/schema/StringVisitor.java

@@ -39,11 +39,7 @@ public Schema builtAvroSchema() {
             // should we construct JavaType for `Character.class` in case of primitive or... ?
             return AvroSchemaHelper.numericAvroSchema(NumberType.INT, _type);
         }
-        // [dataformats-binary#179]: need special help with UUIDs, to coerce into Binary
-        //   (could actually be
-        if (_type.hasRawClass(java.util.UUID.class)) {
-            return AvroSchemaHelper.createUUIDSchema();
-        }
+
         BeanDescription bean = _provider.getConfig().introspectClassAnnotations(_type);
         Schema schema = Schema.create(Schema.Type.STRING);
         // Stringable classes need to include the type

avro/src/main/java/com/fasterxml/jackson/dataformat/avro/schema/UUIDVisitor.java

@@ -0,0 +1,42 @@
+package com.fasterxml.jackson.dataformat.avro.schema;
+
+import com.fasterxml.jackson.databind.jsonFormatVisitors.JsonStringFormatVisitor;
+import com.fasterxml.jackson.databind.jsonFormatVisitors.JsonValueFormat;
+import org.apache.avro.LogicalTypes;
+import org.apache.avro.Schema;
+
+import java.util.Set;
+
+/**
+ * Visitor for {@link java.util.UUID} type. When it is created with logicalTypesEnabled enabled,
+ * Avro schema is created with logical type uuid.
+ *
+ * @since 2.19
+ */
+public class UUIDVisitor extends JsonStringFormatVisitor.Base
+        implements SchemaBuilder {
+    protected boolean _logicalTypesEnabled = false;
+
+
+    public UUIDVisitor(boolean logicalTypesEnabled) {
+        _logicalTypesEnabled = logicalTypesEnabled;
+    }
+
+    @Override
+    public void format(JsonValueFormat format) {
+        // Ideally, we'd recognize UUIDs, Dates etc if need be, here...
+    }
+
+    @Override
+    public void enumTypes(Set<String> enums) {
+        // Do nothing
+    }
+
+    @Override
+    public Schema builtAvroSchema() {
+        // [dataformats-binary#179]: need special help with UUIDs, to coerce into Binary
+        //   (could actually be
+        Schema schema = AvroSchemaHelper.createUUIDSchema();
+        return this._logicalTypesEnabled ? LogicalTypes.uuid().addToSchema(schema) : schema;
+    }
+}

avro/src/main/java/com/fasterxml/jackson/dataformat/avro/schema/VisitorFormatWrapperImpl.java

@@ -214,6 +214,12 @@ public JsonStringFormatVisitor expectStringFormat(JavaType type)
             return v;
         }
 
+        if (type.hasRawClass(java.util.UUID.class)) {
+            UUIDVisitor v = new UUIDVisitor(this._logicalTypesEnabled);
+            _builder = v;
+            return v;
+        }
+
         StringVisitor v = new StringVisitor(_provider, type);
         _builder = v;
         return v;

avro/src/test/java/com/fasterxml/jackson/dataformat/avro/schema/UUIDVisitor_builtAvroSchemaTest.java

@@ -0,0 +1,45 @@
+package com.fasterxml.jackson.dataformat.avro.schema;
+
+import org.apache.avro.LogicalType;
+import org.apache.avro.Schema;
+import org.junit.Test;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+public class UUIDVisitor_builtAvroSchemaTest {
+
+    @Test
+    public void testLogicalTypesDisabled() {
+        // GIVEN
+        boolean logicalTypesEnabled = false;
+        UUIDVisitor uuidVisitor = new UUIDVisitor(logicalTypesEnabled);
+
+        // WHEN
+        Schema actualSchema = uuidVisitor.builtAvroSchema();
+
+        // THEN
+        assertThat(actualSchema.getType()).isEqualTo(Schema.Type.FIXED);
+        assertThat(actualSchema.getFixedSize()).isEqualTo(16);
+        assertThat(actualSchema.getName()).isEqualTo("UUID");
+        assertThat(actualSchema.getNamespace()).isEqualTo("java.util");
+        assertThat(actualSchema.getProp(LogicalType.LOGICAL_TYPE_PROP)).isNull();
+    }
+
+    @Test
+    public void testLogicalTypesEnabled() {
+        // GIVEN
+        boolean logicalTypesEnabled = true;
+        UUIDVisitor uuidVisitor = new UUIDVisitor(logicalTypesEnabled);
+
+        // WHEN
+        Schema actualSchema = uuidVisitor.builtAvroSchema();
+
+        // THEN
+        assertThat(actualSchema.getType()).isEqualTo(Schema.Type.FIXED);
+        assertThat(actualSchema.getFixedSize()).isEqualTo(16);
+        assertThat(actualSchema.getName()).isEqualTo("UUID");
+        assertThat(actualSchema.getNamespace()).isEqualTo("java.util");
+        assertThat(actualSchema.getProp(LogicalType.LOGICAL_TYPE_PROP)).isEqualTo("uuid");
+    }
+
+}