Expected behavior
Generated code calls @AfterMapping method only once. Here is the generated output for MapStruct 1.5.5:
@Generated(
value = "org.mapstruct.ap.MappingProcessor",
date = "2024-08-19T16:21:29+0200",
comments = "version: 1.5.5.Final, compiler: javac, environment: Java 21.0.2 (Oracle Corporation)"
)
class MappingExample$SimpleSourceDestinationMapperImpl extends MappingExample.SimpleSourceDestinationMapper {
@Override
MappingExample.SimpleDestination sourceToDestination(MappingExample.SimpleSource source) {
if ( source == null ) {
return null;
}
MappingExample.SimpleDestination.SimpleDestinationBuilder simpleDestination = MappingExample.SimpleDestination.builder();
simpleDestination.name( source.getName() );
simpleDestination.description( source.getDescription() );
afterMapping( source );
return simpleDestination.build();
}
}Actual behavior
@AfterMapping method is called before and after using the build() method of the builder pattern.
@Generated(
value = "org.mapstruct.ap.MappingProcessor",
date = "2024-08-19T16:24:57+0200",
comments = "version: 1.6.0, compiler: javac, environment: Java 21.0.2 (Oracle Corporation)"
)
class MappingExample$SimpleSourceDestinationMapperImpl extends MappingExample.SimpleSourceDestinationMapper {
@Override
MappingExample.SimpleDestination sourceToDestination(MappingExample.SimpleSource source) {
if ( source == null ) {
return null;
}
MappingExample.SimpleDestination.SimpleDestinationBuilder simpleDestination = MappingExample.SimpleDestination.builder();
simpleDestination.name( source.getName() );
simpleDestination.description( source.getDescription() );
afterMapping( source );
SimpleDestination simpleDestinationResult = simpleDestination.build();
afterMapping( source );
return simpleDestinationResult;
}
}Steps to reproduce the problem
pom.xml
<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>com.example</groupId>
<artifactId>test-mapstruct-issue</artifactId>
<version>1.0-SNAPSHOT</version>
<properties>
<maven.compiler.source>21</maven.compiler.source>
<maven.compiler.target>21</maven.compiler.target>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
</properties>
<dependencies>
<dependency>
<groupId>org.mapstruct</groupId>
<artifactId>mapstruct</artifactId>
<version>1.6.0</version>
</dependency>
<dependency>
<groupId>org.projectlombok</groupId>
<artifactId>lombok</artifactId>
<version>1.18.34</version>
</dependency>
<dependency>
<groupId>org.projectlombok</groupId>
<artifactId>lombok-mapstruct-binding</artifactId>
<version>0.2.0</version>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-compiler-plugin</artifactId>
<version>3.11.0</version>
<configuration>
<annotationProcessorPaths>
<path>
<groupId>org.mapstruct</groupId>
<artifactId>mapstruct-processor</artifactId>
<version>1.6.0</version>
</path>
<path>
<groupId>org.projectlombok</groupId>
<artifactId>lombok</artifactId>
<version>1.18.34</version>
</path>
<path>
<groupId>org.projectlombok</groupId>
<artifactId>lombok-mapstruct-binding</artifactId>
<version>0.2.0</version>
</path>
</annotationProcessorPaths>
</configuration>
</plugin>
</plugins>
</build>
</project>Code example:
import lombok.Builder;
import lombok.Data;
import org.mapstruct.AfterMapping;
import org.mapstruct.Mapper;
public class MappingExample {
@Data
public static class SimpleSource {
private String name;
private String description;
}
@Data
@Builder
public static final class SimpleDestination {
private final String name;
private final String description;
}
@Mapper
abstract static class SimpleSourceDestinationMapper {
abstract SimpleDestination sourceToDestination(SimpleSource source);
@AfterMapping
void afterMapping(SimpleSource simpleSource) {
// do something
}
}
}MapStruct Version
MapStruct 1.6.0
Expected behavior
Generated code calls
@AfterMappingmethod only once. Here is the generated output for MapStruct 1.5.5:Actual behavior
@AfterMappingmethod is called before and after using the build() method of the builder pattern.Steps to reproduce the problem
pom.xml
Code example:
MapStruct Version
MapStruct 1.6.0