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Copy constructor using reflection

I have a Base class with 100 fields and a Derived class with two more fields. I want all 100 fields to be accessible in the Derived class by calling getters in the base class, so I use inheritance, not composition. In Derived, I want to have a constructor that initializes everything from Base:

class Base {
  ... // 100 fields.
}

class Derived extends Base {
  ... // 2 more fields.
  Derived (Base base) {
    ... // Initialize here all 100 fields from base. Don't care about my 2 fields, can have default values.
  }
}
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2 answers

If you need to fill out a bean from another that has the same properties (more or less), you will surely find something here:

http://commons.apache.org/proper/commons-beanutils/

In particular

http://commons.apache.org/proper/commons-beanutils/javadocs/v1.9.1/apidocs/org/apache/commons/beanutils/BeanUtils.html

, BeanUtils.copyProperties(Object orig, Object dest) , , .

+4

a Constructor Base, , super .

public class Parent {

    public Parent(String field1, String field2) {
       // Creates parent.
    }
}

public class Child extends Parent {

     public Child(String field1, String field2)
     {
        super(field1, field2);
     }
}
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