BeanUtils copyProperties to copy Arraylist

Question

I know that BeanUtils can copy a single object to other.

Is it possible to copy an arraylist.

For example:

 FromBean fromBean = new FromBean("fromBean", "fromBeanAProp", "fromBeanBProp");
 ToBean toBean = new ToBean("toBean", "toBeanBProp", "toBeanCProp");
 BeanUtils.copyProperties(toBean, fromBean);

How to achieve this?

List<FromBean > fromBeanList = new ArrayList<FromBean >();  
List<ToBean > toBeanList = new ArrayList<ToBean >();  
BeanUtils.copyProperties(toBeanList , fromBeanList );

Its not working for me. Can any one please help me.

Thanks in advance.

score 18 · Answer 1 · answered May 14 '15 at 11:19

18

If you have a list origin with data and list destination empty, the solution is:

    List<Object> listOrigin (with data)
    List<Object> listDestination= new ArrayList<Object>(); 

     for (Object source: listOrigin ) {
        Object target= new Object();
        BeanUtils.copyProperties(source , target);
        listDestination.add(target);
     }

answered May 14 '15 at 11:19

David Gonzalez

751
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2

This one is actually the correct implementation rather than the accepted answer.! – Md Faisal Mar 26 '17 at 12:50

score 9 · Accepted Answer · answered Oct 11 '13 at 07:08

9

If you have two lists of equals size then you can do the following

for (int i = 0; i < fromBeanList.size(); i++) {
     BeanUtils.copyProperties(toBeanList.get(i), fromBeanList.get(i));
}

answered Oct 11 '13 at 07:08

Evgeniy Dorofeev

133,369
30
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275

Ya now i did it like this But i want to know to copy fully at once thanks – Monicka Akilan Oct 11 '13 at 07:30
Don't forget that copyProperties only copies properties that have a public set method it does not use reflection. – Pedro Bacchini Jan 27 '20 at 16:52

score 2 · Answer 3 · edited Jun 07 '16 at 08:26

What you can do is to write your own generic copy class.

class CopyVector<S, T> {
    private Class<T> targetType;
    CopyVector(Class<T> targetType) {
        this.targetType = targetType;
    }
    Vector<T> copy(Vector<S> src) {
        Vector<T> target = new Vector<T>();
        for ( S s : src ) {
            T t = BeanUtils.instantiateClass(targetType);
            BeanUtils.copyProperties(s, t);
            target.add(t);
        }
        return target;
    }
}

A step further would also be to make the List type generic - this assumes you want to copy Vectors.

score 1 · Answer 4 · answered Oct 11 '13 at 07:10

1

you can try something like this

for(int i=0; i<fromBeanList.size(); i++){
  BeanUtils.copyProperties(toBeanList.get(i) , fromBeanList.get(i) );
}

Hope this helps..

Oops it is already explained by someone now..

anyways try it.

answered Oct 11 '13 at 07:10

Ashish

735
1
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15

score 0 · Answer 5 · answered Oct 11 '13 at 07:03

0

BeanUtils.copyProperties, It only copy the property of same name. So, In case of ArrayList you can't do that.

According to docs:

Copy property values from the origin bean to the destination bean for all cases where the property names are the same.

answered Oct 11 '13 at 07:03

Masudul

21,823
5
43
58

score 0 · Answer 6 · answered Feb 04 '20 at 15:23

In spring BeanUtils.copyProperties, arguments are just opposite than apache commons lib

for(FromBean fromBean: fromBeanList) {
    if(fromBean != null) {
        ToBean toBean = new ToBean();
        org.springframework.beans.BeanUtils.copyProperties(fromBean, toBean);
        toBeanList.add(toBean);
    }
}

martin robin A · Answer 7 · 2020-07-30T12:37:30.830

0

public List<"ToBean"> getAll() {
create an empty list of the Target folder

List<'ToBean>' toBeanList = new ArrayList<'ToBean'>();
Create a empty object of Target folder
ToBean toBean = new ToBean();
List<'FromBean > fromBeanList = beanRepository.findAll();
//Iterate Src Bean
for(fromBean : fromBeanList)
{
BeanUtils.copyProperties(fromBean , toBean );
toBeanList .add(toBean );
}
return toBeanList ; }

edited Jul 30 '20 at 12:37

answered Jul 30 '20 at 12:23

martin robin A

1
1

1

Welcome to Stack Overflow. I suggest you separate code and explanation into separate parts in your answer. Also format the code, refer to the [help page on Markdown](https://stackoverflow.com/editing-help) on how to do it. Possibly you also want to refer to [How do I write a good answer?](https://stackoverflow.com/help/how-to-answer). – Ivo Mori Jul 30 '20 at 12:46

score -1 · Answer 8 · edited Nov 25 '20 at 12:51

What i used just now :

     public static List<?\> copyPropertiesArray(List<?\> source, List<?\> destination,Class<?\> destinationClass) throws CopyPropertiesException {
                
                  try {
                    //the destination size must be the same as the source size and also it must be typed correctly (thus the need for the 3rd argument)         
                     destination=Collections.nCopies(source.size(),destinationClass.newInstance()); //initialize the desination list to same size as the source         
                       for (int i = 0; i < source.size(); i++) {                
                          BeanUtils.copyProperties(destination.get(i), source.get(i));
                       }

                       return destination;

                    } catch (IllegalAccessException | InvocationTargetException | InstantiationException e) {
                    
                       throw new Exception(e.getMessage());
    
                    }
            }

BeanUtils copyProperties to copy Arraylist

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