Getting Null while trying to map a response of list type to another object using dozzer mapping with custom converter

Question

i have searched everywhere but didn't get a solution for my problem. I have following class:

    class Output{
        private List<Response> response=new ArrayList<Response>();
        public List<Response> getResponse(){
return this.response;}
public void setResponse(final List<Response> response) { 
this.response= response;}
}
class Response
private String amount
public String getAmount(){ 
return this.amount;}
public void setAmount(String amount) { 
this.amount = amount;}
}

i have another set of class as

class Otherlist{
private List<Otherresponse> otherresponse=new ArrayList<Otherresponse>();
public List<Otherresponse> getOtherResponse(){
return this.otherresponse;}
public void setOtherResponse(final List<Otherresponse> otherresponse) { 
this.otherresponse= otherresponse;}
}

class Otherresponse{
private String  iamount
public String getIamount() { 
return iamount;}
public void setIamount(final String iamount) { 
this.iamount = iamount;}
}

The mapping xml looks like DozzerMapping.xml

<mapping>
<class-a>Response</class-a>
<class-b>Otherresponse</class-b>
<field>
<a>amount</a>
<b>iamount</b>
</field>
</mapping>

and i have a controller class where i receive the json response as a list of object.However i need to map the received list of object(Response class) to front end(Otherresponse class).I am not able to map the values from Response to Otherresponse .On printing the otherresponse object i am getting null.The controller class for mapping looks as following:

public class Controller{
Otherresponse otherresponse= this.dozerMapper.map(response.getBody(), Otherresponse.class)

}