Expected behavior
I have a mapper annotated DeepClone to perform a copy clone of some bean. I notice that the generated implementation on java.util.Date field it perform a simple a.setDate(b.getDate()). This could be ok for String or BigDecimal object that are immutable but old java Date object are not immutable that mean if I change b.getDate().setTime(1l) it will also update date in the bean a.
What I expect is that in case of DeepClone it produce the following code:
@Override
public BeanA clone(BeanA value) {
if ( value == null ) {
return null;
}
BeanA beanA = new BeanA();
if (source.getDate() != null) {
beanA.setDate(new Date(source.getDate().getTime())); // expected behaviour
}
return beanA;
}
Actual behavior
The generated code is
@Generated(
value = "org.mapstruct.ap.MappingProcessor",
date = "2025-09-16T10:12:55+0200",
comments = "version: 1.6.3, compiler: Eclipse JDT (IDE) 3.41.0.v20250213-1140, environment: Java 21.0.6 (Eclipse Adoptium)"
)
public class ICloneMapperImpl implements ICloneMapper {
@Override
public BeanA clone(BeanA value) {
if ( value == null ) {
return null;
}
BeanA beanA = new BeanA();
beanA.setDate(source.getDate());
return beanA;
}
}
Steps to reproduce the problem
Create the following classes
public class BeanA {
private Date date;
public Date getDate() { return date; }
public void setDate(Date value) { date = value; }
}
@Mapper(mappingControl = DeepClone.class)
public interface ICloneMapper {
BeanA clone(BeanA source);
}
MapStruct Version
MapStruct 1.6.3
Workaround
In the ICloneMapper I have to define a method like this:
default Date map(Date value) {
return value != null ? new Date(value.getTime()) : null;
}
to get the clone of date.
Expected behavior
I have a mapper annotated DeepClone to perform a copy clone of some bean. I notice that the generated implementation on java.util.Date field it perform a simple
a.setDate(b.getDate()). This could be ok for String or BigDecimal object that are immutable but old java Date object are not immutable that mean if I changeb.getDate().setTime(1l)it will also update date in the bean a.What I expect is that in case of DeepClone it produce the following code:
Actual behavior
The generated code is
Steps to reproduce the problem
Create the following classes
MapStruct Version
MapStruct 1.6.3
Workaround
In the ICloneMapper I have to define a method like this:
to get the clone of date.