BeanUtils. Copyproperties() vs. mapstruct

original text

BeanUtils.copyProperties() contrast mapstruct

List of articles

• • 1. The difference between deep copy and shallow copy
  • 2.BeanUtils Deep copy or shallow copy
  • 3.mapstruct Deep copy or shallow copy
  • 4.BeanUtils.copyProperties() VS mapstruct Performance comparison
  • Conclusion

1. Deep copy Difference from shallow copy

Shallow copy （shallowCopy） It just adds a pointer to an existing memory address ,

Deep copy （deepCopy） A pointer is added and a new memory is requested , Make the added pointer point to the new memory ,

The fundamental difference between deep copy and shallow copy is whether or not to get the copy entity of an object , Not references .
hypothesis B Copy the A, modify A When , see B Is there a change ：

If B And then it changed , The description is a shallow copy , Short hand ！（ Modify the same value in heap memory ）

If B There is no change , The description is a deep copy , Support oneself ！（ Modify different values in heap memory ）

2.BeanUtils Deep copy or shallow copy

Copying a simple object is a deep copy
When copying complex objects ( Object properties hold objects ) Is a shallow copy

3.mapstruct Deep copy or shallow copy

Copying a simple object is a deep copy
When copying complex objects ( Object properties hold objects ) Is a shallow copy

4.BeanUtils.copyProperties() VS mapstruct Performance comparison

Conclusion

BeanUtils.copyProperties() and mapstruct It's all shallow copies , The difference lies in their different performance ,mapstruct Better performance
The copy field needs to be changed , Or some special treatment mapstruct Provide better solutions