I have a Project domain which I want to map on a ProjectDTO using modelmapper. The Project domain contains a List of Locations. In the DTO, I don’t want the Location domains, just the ids of the locations.
public class Project {
private List<Location> locations
}
public class Location {
private Long id;
private String name;
}
public class ProjectDTO {
private List<Long> assignedLocations;
}
So I followed the tutorial of Link and created a custom converter:
public Converter<List<Location>, List<Long>> locationToLongConverter = new Converter<List<Location>, List<Long>>() {
@Override
public List<Long> convert(MappingContext<List<Location>, List<Long>> context) {
List<Location> source = context.getSource();
List<Long> destination = context.getDestination();
for (Location location : source) {
destination.add(location.getId());
}
return destination;
}
};
Then, I created the PropertyMap to tell modelmapp to use the converter for that field:
PropertyMap<Project, ProjectDTO> itemDTOMap = new PropertyMap<Project, ProjectDTO>() {
@Override
protected void configure() {
using(locationToLongConverter).map(source.getLocations()).setAssignedLocations(null);
}
};
Finally, I created a bean in my SpringBootApplication class:
@Bean
public ModelMapper modelMapper() {
ModelMapper mapper = new ModelMapper();
mapper.addMappings(projectConverter.getItemDTOMap());
return mapper;
}
But it is not working, I get errors when starting the application.
nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [org.modelmapper.ModelMapper]: Factory method 'modelMapper' threw exception; nested exception is org.modelmapper.ConfigurationException: ModelMapper configuration errors:
1) Failed to configure mappings
1 error
at org.springframework.beans.factory.support.ConstructorResolver.createArgumentArray(ConstructorResolver.java:798) ~[spring-beans-5.2.5.RELEASE.jar:5.2.5.RELEASE]
at org.springframework.beans.factory.support.ConstructorResolver.autowireConstructor(ConstructorResolver.java:228) ~[spring-beans-5.2.5.RELEASE.jar:5.2.5.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.autowireConstructor(AbstractAutowireCapableBeanFactory.java:1358) ~[spring-beans-5.2.5.RELEASE.jar:5.2.5.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:1204) ~[spring-beans-5.2.5.RELEASE.jar:5.2.5.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:557) ~[spring-beans-5.2.5.RELEASE.jar:5.2.5.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:517) ~[spring-beans-5.2.5.RELEASE.jar:5.2.5.RELEASE]
at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:323) ~[spring-beans-5.2.5.RELEASE.jar:5.2.5.RELEASE]
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:222) ~[spring-beans-5.2.5.RELEASE.jar:5.2.5.RELEASE]
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:321) ~[spring-beans-5.2.5.RELEASE.jar:5.2.5.RELEASE]
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:202) ~[spring-beans-5.2.5.RELEASE.jar:5.2.5.RELEASE]
at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:882) ~[spring-beans-5.2.5.RELEASE.jar:5.2.5.RELEASE]
at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:878) ~[spring-context-5.2.5.RELEASE.jar:5.2.5.RELEASE]
at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:550) ~[spring-context-5.2.5.RELEASE.jar:5.2.5.RELEASE]
at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.refresh(ServletWebServerApplicationContext.java:141) ~[spring-boot-2.2.6.RELEASE.jar:2.2.6.RELEASE]
at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:747) ~[spring-boot-2.2.6.RELEASE.jar:2.2.6.RELEASE]
at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:397) ~[spring-boot-2.2.6.RELEASE.jar:2.2.6.RELEASE]
at org.springframework.boot.SpringApplication.run(SpringApplication.java:315) ~[spring-boot-2.2.6.RELEASE.jar:2.2.6.RELEASE]
at org.springframework.boot.SpringApplication.run(SpringApplication.java:1226) ~[spring-boot-2.2.6.RELEASE.jar:2.2.6.RELEASE]
at org.springframework.boot.SpringApplication.run(SpringApplication.java:1215) ~[spring-boot-2.2.6.RELEASE.jar:2.2.6.RELEASE]
at de.qedcon.moscowmule.MoscowMuleApplication.main(MoscowMuleApplication.java:25) ~[classes/:na]
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:na]
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:na]
at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:na]
at java.base/java.lang.reflect.Method.invoke(Method.java:566) ~[na:na]
at org.springframework.boot.devtools.restart.RestartLauncher.run(RestartLauncher.java:49) ~[spring-boot-devtools-2.2.6.RELEASE.jar:2.2.6.RELEASE]
Caused by: org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'locationManagementServiceImpl' defined in file [D:DevelopmentqedconmoscowmuletargetclassesdeqedconmoscowmulelocationmanagementserviceLocationManagementServiceImpl.class]: Unsatisfied dependency expressed through constructor parameter 5; nested exception is org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'userManagementServiceImpl' defined in file [D:DevelopmentqedconmoscowmuletargetclassesdeqedconmoscowmuleusermanagementserviceUserManagementServiceImpl.class]: Unsatisfied dependency expressed through constructor parameter 3; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'modelMapper' defined in de.qedcon.moscowmule.MoscowMuleApplication: Bean instantiation via factory method failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [org.modelmapper.ModelMapper]: Factory method 'modelMapper' threw exception; nested exception is org.modelmapper.ConfigurationException: ModelMapper configuration errors:
1) Failed to configure mappings
1 error
at org.springframework.beans.factory.support.ConstructorResolver.createArgumentArray(ConstructorResolver.java:798) ~[spring-beans-5.2.5.RELEASE.jar:5.2.5.RELEASE]
at org.springframework.beans.factory.support.ConstructorResolver.autowireConstructor(ConstructorResolver.java:228) ~[spring-beans-5.2.5.RELEASE.jar:5.2.5.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.autowireConstructor(AbstractAutowireCapableBeanFactory.java:1358) ~[spring-beans-5.2.5.RELEASE.jar:5.2.5.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:1204) ~[spring-beans-5.2.5.RELEASE.jar:5.2.5.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:557) ~[spring-beans-5.2.5.RELEASE.jar:5.2.5.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:517) ~[spring-beans-5.2.5.RELEASE.jar:5.2.5.RELEASE]
at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:323) ~[spring-beans-5.2.5.RELEASE.jar:5.2.5.RELEASE]
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:222) ~[spring-beans-5.2.5.RELEASE.jar:5.2.5.RELEASE]
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:321) ~[spring-beans-5.2.5.RELEASE.jar:5.2.5.RELEASE]
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:202) ~[spring-beans-5.2.5.RELEASE.jar:5.2.5.RELEASE]
at org.springframework.beans.factory.config.DependencyDescriptor.resolveCandidate(DependencyDescriptor.java:276) ~[spring-beans-5.2.5.RELEASE.jar:5.2.5.RELEASE]
at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1290) ~[spring-beans-5.2.5.RELEASE.jar:5.2.5.RELEASE]
at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:1210) ~[spring-beans-5.2.5.RELEASE.jar:5.2.5.RELEASE]
at org.springframework.beans.factory.support.ConstructorResolver.resolveAutowiredArgument(ConstructorResolver.java:885) ~[spring-beans-5.2.5.RELEASE.jar:5.2.5.RELEASE]
at org.springframework.beans.factory.support.ConstructorResolver.createArgumentArray(ConstructorResolver.java:789) ~[spring-beans-5.2.5.RELEASE.jar:5.2.5.RELEASE]
... 24 common frames omitted
Caused by: org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'userManagementServiceImpl' defined in file [D:DevelopmentqedconmoscowmuletargetclassesdeqedconmoscowmuleusermanagementserviceUserManagementServiceImpl.class]: Unsatisfied dependency expressed through constructor parameter 3; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'modelMapper' defined in de.qedcon.moscowmule.MoscowMuleApplication: Bean instantiation via factory method failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [org.modelmapper.ModelMapper]: Factory method 'modelMapper' threw exception; nested exception is org.modelmapper.ConfigurationException: ModelMapper configuration errors:
1) Failed to configure mappings
1 error
at org.springframework.beans.factory.support.ConstructorResolver.createArgumentArray(ConstructorResolver.java:798) ~[spring-beans-5.2.5.RELEASE.jar:5.2.5.RELEASE]
at org.springframework.beans.factory.support.ConstructorResolver.autowireConstructor(ConstructorResolver.java:228) ~[spring-beans-5.2.5.RELEASE.jar:5.2.5.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.autowireConstructor(AbstractAutowireCapableBeanFactory.java:1358) ~[spring-beans-5.2.5.RELEASE.jar:5.2.5.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:1204) ~[spring-beans-5.2.5.RELEASE.jar:5.2.5.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:557) ~[spring-beans-5.2.5.RELEASE.jar:5.2.5.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:517) ~[spring-beans-5.2.5.RELEASE.jar:5.2.5.RELEASE]
at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:323) ~[spring-beans-5.2.5.RELEASE.jar:5.2.5.RELEASE]
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:222) ~[spring-beans-5.2.5.RELEASE.jar:5.2.5.RELEASE]
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:321) ~[spring-beans-5.2.5.RELEASE.jar:5.2.5.RELEASE]
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:202) ~[spring-beans-5.2.5.RELEASE.jar:5.2.5.RELEASE]
at org.springframework.beans.factory.config.DependencyDescriptor.resolveCandidate(DependencyDescriptor.java:276) ~[spring-beans-5.2.5.RELEASE.jar:5.2.5.RELEASE]
at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1290) ~[spring-beans-5.2.5.RELEASE.jar:5.2.5.RELEASE]
at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:1210) ~[spring-beans-5.2.5.RELEASE.jar:5.2.5.RELEASE]
at org.springframework.beans.factory.support.ConstructorResolver.resolveAutowiredArgument(ConstructorResolver.java:885) ~[spring-beans-5.2.5.RELEASE.jar:5.2.5.RELEASE]
at org.springframework.beans.factory.support.ConstructorResolver.createArgumentArray(ConstructorResolver.java:789) ~[spring-beans-5.2.5.RELEASE.jar:5.2.5.RELEASE]
... 38 common frames omitted
Caused by: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'modelMapper' defined in de.qedcon.moscowmule.MoscowMuleApplication: Bean instantiation via factory method failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [org.modelmapper.ModelMapper]: Factory method 'modelMapper' threw exception; nested exception is org.modelmapper.ConfigurationException: ModelMapper configuration errors:
1) Failed to configure mappings
1 error
at org.springframework.beans.factory.support.ConstructorResolver.instantiate(ConstructorResolver.java:656) ~[spring-beans-5.2.5.RELEASE.jar:5.2.5.RELEASE]
at org.springframework.beans.factory.support.ConstructorResolver.instantiateUsingFactoryMethod(ConstructorResolver.java:484) ~[spring-beans-5.2.5.RELEASE.jar:5.2.5.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.instantiateUsingFactoryMethod(AbstractAutowireCapableBeanFactory.java:1338) ~[spring-beans-5.2.5.RELEASE.jar:5.2.5.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:1177) ~[spring-beans-5.2.5.RELEASE.jar:5.2.5.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:557) ~[spring-beans-5.2.5.RELEASE.jar:5.2.5.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:517) ~[spring-beans-5.2.5.RELEASE.jar:5.2.5.RELEASE]
at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:323) ~[spring-beans-5.2.5.RELEASE.jar:5.2.5.RELEASE]
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:222) ~[spring-beans-5.2.5.RELEASE.jar:5.2.5.RELEASE]
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:321) ~[spring-beans-5.2.5.RELEASE.jar:5.2.5.RELEASE]
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:202) ~[spring-beans-5.2.5.RELEASE.jar:5.2.5.RELEASE]
at org.springframework.beans.factory.config.DependencyDescriptor.resolveCandidate(DependencyDescriptor.java:276) ~[spring-beans-5.2.5.RELEASE.jar:5.2.5.RELEASE]
at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1290) ~[spring-beans-5.2.5.RELEASE.jar:5.2.5.RELEASE]
at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:1210) ~[spring-beans-5.2.5.RELEASE.jar:5.2.5.RELEASE]
at org.springframework.beans.factory.support.ConstructorResolver.resolveAutowiredArgument(ConstructorResolver.java:885) ~[spring-beans-5.2.5.RELEASE.jar:5.2.5.RELEASE]
at org.springframework.beans.factory.support.ConstructorResolver.createArgumentArray(ConstructorResolver.java:789) ~[spring-beans-5.2.5.RELEASE.jar:5.2.5.RELEASE]
... 52 common frames omitted
Caused by: org.springframework.beans.BeanInstantiationException: Failed to instantiate [org.modelmapper.ModelMapper]: Factory method 'modelMapper' threw exception; nested exception is org.modelmapper.ConfigurationException: ModelMapper configuration errors:
1) Failed to configure mappings
1 error
at org.springframework.beans.factory.support.SimpleInstantiationStrategy.instantiate(SimpleInstantiationStrategy.java:185) ~[spring-beans-5.2.5.RELEASE.jar:5.2.5.RELEASE]
at org.springframework.beans.factory.support.ConstructorResolver.instantiate(ConstructorResolver.java:651) ~[spring-beans-5.2.5.RELEASE.jar:5.2.5.RELEASE]
... 66 common frames omitted
Caused by: org.modelmapper.ConfigurationException: ModelMapper configuration errors:
1) Failed to configure mappings
1 error
at org.modelmapper.internal.Errors.throwConfigurationExceptionIfErrorsExist(Errors.java:241) ~[modelmapper-2.3.0.jar:na]
at org.modelmapper.internal.ExplicitMappingBuilder.build(ExplicitMappingBuilder.java:244) ~[modelmapper-2.3.0.jar:na]
at org.modelmapper.internal.ExplicitMappingBuilder.build(ExplicitMappingBuilder.java:96) ~[modelmapper-2.3.0.jar:na]
at org.modelmapper.internal.TypeMapImpl.addMappings(TypeMapImpl.java:92) ~[modelmapper-2.3.0.jar:na]
at org.modelmapper.internal.TypeMapStore.getOrCreate(TypeMapStore.java:124) ~[modelmapper-2.3.0.jar:na]
at org.modelmapper.ModelMapper.addMappings(ModelMapper.java:113) ~[modelmapper-2.3.0.jar:na]
at de.qedcon.moscowmule.MoscowMuleApplication.modelMapper(MoscowMuleApplication.java:38) ~[classes/:na]
at de.qedcon.moscowmule.MoscowMuleApplication$$EnhancerBySpringCGLIB$$1c0b08e7.CGLIB$modelMapper$0(<generated>) ~[classes/:na]
at de.qedcon.moscowmule.MoscowMuleApplication$$EnhancerBySpringCGLIB$$1c0b08e7$$FastClassBySpringCGLIB$$8262a926.invoke(<generated>) ~[classes/:na]
at org.springframework.cglib.proxy.MethodProxy.invokeSuper(MethodProxy.java:244) ~[spring-core-5.2.5.RELEASE.jar:5.2.5.RELEASE]
at org.springframework.context.annotation.ConfigurationClassEnhancer$BeanMethodInterceptor.intercept(ConfigurationClassEnhancer.java:331) ~[spring-context-5.2.5.RELEASE.jar:5.2.5.RELEASE]
at de.qedcon.moscowmule.MoscowMuleApplication$$EnhancerBySpringCGLIB$$1c0b08e7.modelMapper(<generated>) ~[classes/:na]
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:na]
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:na]
at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:na]
at java.base/java.lang.reflect.Method.invoke(Method.java:566) ~[na:na]
at org.springframework.beans.factory.support.SimpleInstantiationStrategy.instantiate(SimpleInstantiationStrategy.java:154) ~[spring-beans-5.2.5.RELEASE.jar:5.2.5.RELEASE]
... 67 common frames omitted
Caused by: java.lang.UnsupportedOperationException: null
at org.modelmapper.internal.asm.ClassVisitor.visitNestHostExperimental(ClassVisitor.java:158) ~[modelmapper-2.3.0.jar:na]
at org.modelmapper.internal.asm.ClassReader.accept(ClassReader.java:541) ~[modelmapper-2.3.0.jar:na]
at org.modelmapper.internal.asm.ClassReader.accept(ClassReader.java:391) ~[modelmapper-2.3.0.jar:na]
at org.modelmapper.internal.ExplicitMappingBuilder.visitPropertyMap(ExplicitMappingBuilder.java:259) ~[modelmapper-2.3.0.jar:na]
at org.modelmapper.PropertyMap.configure(PropertyMap.java:386) ~[modelmapper-2.3.0.jar:na]
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:na]
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:na]
at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:na]
at java.base/java.lang.reflect.Method.invoke(Method.java:566) ~[na:na]
at org.modelmapper.internal.ExplicitMappingBuilder.build(ExplicitMappingBuilder.java:227) ~[modelmapper-2.3.0.jar:na]
... 82 common frames omitted
Here the full ProjectConverter class:
@Service
@Getter @RequiredArgsConstructor
public class ProjectConverter {
public Converter<List<Location>, List<Long>> locationToLongConverter = new Converter<List<Location>, List<Long>>() {
@Override
public List<Long> convert(MappingContext<List<Location>, List<Long>> context) {
List<Location> source = context.getSource();
List<Long> destination = context.getDestination();
for (Location location : source) {
destination.add(location.getId());
}
return destination;
}
};
PropertyMap<Project, ProjectDTO> itemDTOMap = new PropertyMap<Project, ProjectDTO>() {
@Override
protected void configure() {
using(locationToLongConverter).map(Project::getLocations, ProjectDTO::setAssignedLocations);
}
};
}
Any ideas what I do wrong?
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Answer
This is a bug of ModelMapper, fixed on version 2.3.2 or later:
In addition, NPE problem on locationToLongConverter#convert() should be fixed:
final List<Long> destination = new ArrayList<>();
By the way, this code could be written more simply:
@Bean
public ModelMapper modelMapper() {
final Converter<List<Location>, List<Long>> locationConverter = ctx -> ctx.getSource().stream()
.map(Location::getId).collect(Collectors.toList());
final ModelMapper mapper = new ModelMapper();
mapper.typeMap(Project.class, ProjectDTO.class)
.addMappings(m -> {
m.using(locationConverter).map(Project::getLocations, ProjectDTO::setAssignedLocations);
});
return mapper;
}
(ProjectConverter.java is not required.)
refs: