Adds fluent getters detection for immutables

mapstruct · thmasker · Jul 31, 2025 · Jul 31, 2025 · Aug 10, 2025 · Jul 31, 2025
commit e53da5054c674edb2de4fc913c26e9cd876f244b
diff --git a/processor/src/main/java/org/mapstruct/ap/spi/DefaultAccessorNamingStrategy.java b/processor/src/main/java/org/mapstruct/ap/spi/DefaultAccessorNamingStrategy.java
@@ -6,7 +6,6 @@
 package org.mapstruct.ap.spi;
 
 import java.util.regex.Pattern;
-
 import javax.lang.model.element.ExecutableElement;
 import javax.lang.model.element.TypeElement;
 import javax.lang.model.type.DeclaredType;
@@ -26,7 +25,7 @@
  */
 public class DefaultAccessorNamingStrategy implements AccessorNamingStrategy {
 
-    private static final Pattern JAVA_JAVAX_PACKAGE = Pattern.compile( "^javax?\\..*" );
+    protected static final Pattern JAVA_JAVAX_PACKAGE = Pattern.compile( "^javax?\\..*" );
 
     protected Elements elementUtils;
     protected Types typeUtils;

diff --git a/processor/src/main/java/org/mapstruct/ap/spi/ImmutablesAccessorNamingStrategy.java b/processor/src/main/java/org/mapstruct/ap/spi/ImmutablesAccessorNamingStrategy.java
@@ -6,6 +6,7 @@
 package org.mapstruct.ap.spi;
 
 import javax.lang.model.element.ExecutableElement;
+import javax.lang.model.type.TypeKind;
 
 import org.mapstruct.util.Experimental;
 
@@ -19,6 +20,17 @@
 @Experimental("The Immutables accessor naming strategy might change in a subsequent release")
 public class ImmutablesAccessorNamingStrategy extends DefaultAccessorNamingStrategy {
 
+    @Override
+    public boolean isGetterMethod(ExecutableElement method) {
+        return super.isGetterMethod( method ) || isFluentGetter( method );
+    }
+
+    private boolean isFluentGetter(ExecutableElement method) {
+        return method.getParameters().isEmpty() &&
+            method.getReturnType().getKind() != TypeKind.VOID &&
+            !JAVA_JAVAX_PACKAGE.matcher( method.getEnclosingElement().asType().toString() ).matches();
+    }
+
     @Override
     protected boolean isFluentSetter(ExecutableElement method) {
         return super.isFluentSetter( method ) &&

diff --git a/processor/src/test/java/org/mapstruct/ap/test/fluent/getters/Issue1601BuilderProvider.java b/processor/src/test/java/org/mapstruct/ap/test/fluent/getters/Issue1601BuilderProvider.java
@@ -0,0 +1,39 @@
+/*
+ * Copyright MapStruct Authors.
+ *
+ * Licensed under the Apache License version 2.0, available at http://www.apache.org/licenses/LICENSE-2.0
+ */
+package org.mapstruct.ap.test.fluent.getters;
+
+import javax.lang.model.element.Name;
+import javax.lang.model.element.TypeElement;
+
+import org.mapstruct.ap.spi.BuilderInfo;
+import org.mapstruct.ap.spi.BuilderProvider;
+import org.mapstruct.ap.spi.ImmutablesBuilderProvider;
+
+public class Issue1601BuilderProvider extends ImmutablesBuilderProvider implements BuilderProvider {
+
+    @Override
+    protected BuilderInfo findBuilderInfo(TypeElement typeElement) {
+        Name name = typeElement.getQualifiedName();
+        if ( name.toString().endsWith( ".Item" ) ) {
+            BuilderInfo info = findBuilderInfoForImmutables( typeElement );
+            if ( info != null ) {
+                return info;
+            }
+        }
+
+        return super.findBuilderInfo( typeElement );
+    }
+
+    @Override
+    protected BuilderInfo findBuilderInfoForImmutables(TypeElement typeElement) {
+        TypeElement immutableElement = asImmutableElement( typeElement );
+        if ( immutableElement != null ) {
+            return super.findBuilderInfo( immutableElement );
+        }
+        return null;
+    }
+
+}
diff --git a/processor/src/test/java/org/mapstruct/ap/test/fluent/getters/Issue1601Test.java b/processor/src/test/java/org/mapstruct/ap/test/fluent/getters/Issue1601Test.java
@@ -0,0 +1,47 @@
+/*
+ * Copyright MapStruct Authors.
+ *
+ * Licensed under the Apache License version 2.0, available at http://www.apache.org/licenses/LICENSE-2.0
+ */
+package org.mapstruct.ap.test.fluent.getters;
+
+import org.mapstruct.ap.spi.AccessorNamingStrategy;
+import org.mapstruct.ap.spi.BuilderProvider;
+import org.mapstruct.ap.spi.ImmutablesAccessorNamingStrategy;
+import org.mapstruct.ap.test.fluent.getters.domain.ImmutableItem;
+import org.mapstruct.ap.test.fluent.getters.domain.Item;
+import org.mapstruct.ap.test.fluent.getters.dto.ImmutableItemDto;
+import org.mapstruct.ap.test.fluent.getters.dto.ItemDto;
+import org.mapstruct.ap.testutil.IssueKey;
+import org.mapstruct.ap.testutil.ProcessorTest;
+import org.mapstruct.ap.testutil.WithClasses;
+import org.mapstruct.ap.testutil.WithServiceImplementation;
+import org.mapstruct.ap.testutil.WithServiceImplementations;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+@WithClasses({
+    ItemMapper.class,
+    Item.class,
+    ItemDto.class,
+    ImmutableItem.class,
+    ImmutableItemDto.class
+})
+@IssueKey("1601")
+@WithServiceImplementations({
+    @WithServiceImplementation(provides = BuilderProvider.class, value = Issue1601BuilderProvider.class),
+    @WithServiceImplementation(provides = AccessorNamingStrategy.class, value = ImmutablesAccessorNamingStrategy.class)
+})
+public class Issue1601Test {
+
+    @ProcessorTest
+    public void shouldIncludeBuildType() {
+        var item = ImmutableItemDto.builder().id( "test" ).build();
+
+        var target = ItemMapper.INSTANCE.map( item );
+
+        assertThat( target ).isNotNull();
+        assertThat( target.id() ).isEqualTo( "test" );
+    }
+
+}
diff --git a/processor/src/test/java/org/mapstruct/ap/test/fluent/getters/ItemMapper.java b/processor/src/test/java/org/mapstruct/ap/test/fluent/getters/ItemMapper.java
@@ -0,0 +1,21 @@
+/*
+ * Copyright MapStruct Authors.
+ *
+ * Licensed under the Apache License version 2.0, available at http://www.apache.org/licenses/LICENSE-2.0
+ */
+package org.mapstruct.ap.test.fluent.getters;
+
+import org.mapstruct.Builder;
+import org.mapstruct.Mapper;
+import org.mapstruct.ap.test.fluent.getters.domain.Item;
+import org.mapstruct.ap.test.fluent.getters.dto.ItemDto;
+import org.mapstruct.factory.Mappers;
+
+@Mapper(builder = @Builder)
+public abstract class ItemMapper {
+
+    public static final ItemMapper INSTANCE = Mappers.getMapper( ItemMapper.class );
+
+    public abstract Item map(ItemDto itemDTO);
+
+}
diff --git a/processor/src/test/java/org/mapstruct/ap/test/fluent/getters/domain/ImmutableItem.java b/processor/src/test/java/org/mapstruct/ap/test/fluent/getters/domain/ImmutableItem.java
@@ -0,0 +1,101 @@
+/*
+ * Copyright MapStruct Authors.
+ *
+ * Licensed under the Apache License version 2.0, available at http://www.apache.org/licenses/LICENSE-2.0
+ */
+package org.mapstruct.ap.test.fluent.getters.domain;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Objects;
+
+public final class ImmutableItem extends Item {
+
+    private final String id;
+
+    private ImmutableItem(String id) {
+        this.id = id;
+    }
+
+    @Override
+    public String id() {
+        return id;
+    }
+
+    public ImmutableItem withId(String value) {
+        if ( Objects.equals( this.id, value ) ) {
+            return this;
+        }
+        return new ImmutableItem( value );
+    }
+
+    @Override
+    public boolean equals(Object another) {
+        if ( this == another ) {
+            return true;
+        }
+        return another instanceof ImmutableItem && id.equals( ( (ImmutableItem) another ).id );
+    }
+
+    @Override
+    public int hashCode() {
+        int h = 5381;
+        h += ( h << 5 ) + id.hashCode();
+        return h;
+    }
+
+    @Override
+    public String toString() {
+        return "Item{id=" + id + "}";
+    }
+
+    public static ImmutableItem copyOf(Item instance) {
+        if ( instance instanceof ImmutableItem ) {
+            return (ImmutableItem) instance;
+        }
+        return ImmutableItem.builder().from( instance ).build();
+    }
+
+    public static Builder builder() {
+        return new Builder();
+    }
+
+    public static final class Builder {
+
+        private static final long INIT_BIT_ID = 0x1L;
+        private long initBits = 0x1L;
+
+        private String id;
+
+        private Builder() {
+        }
+
+        public Builder from(Item instance) {
+            id( instance.id() );
+            return this;
+        }
+
+        public Builder id(String id) {
+            this.id = id;
+            initBits &= ~INIT_BIT_ID;
+            return this;
+        }
+
+        public ImmutableItem build() {
+            if ( initBits != 0 ) {
+                throw new IllegalStateException( formatRequiredAttributesMessage() );
+            }
+            return new ImmutableItem( id );
+        }
+
+        private String formatRequiredAttributesMessage() {
+            List<String> attributes = new ArrayList<>();
+            if ( ( initBits & INIT_BIT_ID ) != 0 ) {
+                attributes.add( "id" );
+            }
+            return "Cannot build Item, some of required attributes are not set " + attributes;
+        }
+
+    }
+
+}
diff --git a/processor/src/test/java/org/mapstruct/ap/test/fluent/getters/domain/Item.java b/processor/src/test/java/org/mapstruct/ap/test/fluent/getters/domain/Item.java
@@ -0,0 +1,7 @@
+package org.mapstruct.ap.test.fluent.getters.domain;
+
+public abstract class Item {
+
+    public abstract String id();
+
+}
diff --git a/processor/src/test/java/org/mapstruct/ap/test/fluent/getters/dto/ImmutableItemDto.java b/processor/src/test/java/org/mapstruct/ap/test/fluent/getters/dto/ImmutableItemDto.java
@@ -0,0 +1,101 @@
+/*
+ * Copyright MapStruct Authors.
+ *
+ * Licensed under the Apache License version 2.0, available at http://www.apache.org/licenses/LICENSE-2.0
+ */
+package org.mapstruct.ap.test.fluent.getters.dto;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Objects;
+
+public final class ImmutableItemDto extends ItemDto {
+
+    private final String id;
+
+    private ImmutableItemDto(String id) {
+        this.id = id;
+    }
+
+    @Override
+    public String id() {
+        return id;
+    }
+
+    public ImmutableItemDto withId(String value) {
+        if ( Objects.equals( this.id, value ) ) {
+            return this;
+        }
+        return new ImmutableItemDto( value );
+    }
+
+    @Override
+    public boolean equals(Object another) {
+        if ( this == another ) {
+            return true;
+        }
+        return another instanceof ImmutableItemDto && id.equals( ( (ImmutableItemDto) another ).id );
+    }
+
+    @Override
+    public int hashCode() {
+        int h = 5381;
+        h += ( h << 5 ) + id.hashCode();
+        return h;
+    }
+
+    @Override
+    public String toString() {
+        return "ItemDTO{id=" + id + "}";
+    }
+
+    public static ImmutableItemDto copyOf(ItemDto instance) {
+        if ( instance instanceof ImmutableItemDto ) {
+            return (ImmutableItemDto) instance;
+        }
+        return ImmutableItemDto.builder().from( instance ).build();
+    }
+
+    public static Builder builder() {
+        return new Builder();
+    }
+
+    public static final class Builder {
+
+        private static final long INIT_BIT_ID = 0x1L;
+        private long initBits = 0x1L;
+
+        private String id;
+
+        private Builder() {
+        }
+
+        public Builder from(ItemDto instance) {
+            id( instance.id() );
+            return this;
+        }
+
+        public Builder id(String id) {
+            this.id = id;
+            initBits &= ~INIT_BIT_ID;
+            return this;
+        }
+
+        public ImmutableItemDto build() {
+            if ( initBits != 0 ) {
+                throw new IllegalStateException( formatRequiredAttributesMessage() );
+            }
+            return new ImmutableItemDto( id );
+        }
+
+        private String formatRequiredAttributesMessage() {
+            List<String> attributes = new ArrayList<>();
+            if ( ( initBits & INIT_BIT_ID ) != 0 ) {
+                attributes.add( "id" );
+            }
+            return "Cannot build ItemDTO, some of required attributes are not set " + attributes;
+        }
+
+    }
+
+}
diff --git a/processor/src/test/java/org/mapstruct/ap/test/fluent/getters/dto/ItemDto.java b/processor/src/test/java/org/mapstruct/ap/test/fluent/getters/dto/ItemDto.java
@@ -0,0 +1,7 @@
+package org.mapstruct.ap.test.fluent.getters.dto;
+
+public abstract class ItemDto {
+
+    public abstract String id();
+
+}