Code refactoring - long base/super parameter list

Question

These articles detail nicely how to fix long constructors

• Long parameter list in constructor in Java
• What's the best way to refactor a method that has too many (6+) parameters?

But what they don't say is how would we solve the issue with a long super() or base() call? ie

LongConstructorClass(string s1, string s2, string s3, string s4, string s5) { }

InheritsLongConstructorClass() : base("foo","bar","foo","bar","foo") { }

Basically it annoys me when I have multiple constructors and each of them have a long base() call.

Answer 1

The ParameterObject design pattern can be used to combine multiple parameter values into a single object. Consider a design like:

public class MyClassOld { 
     MyClassOld(param1,param2,param3,param4) {...}  
}

Written as

public class ParamObject {
    ParamObject(param1,param2,param3,param4) { }
}

public class MyClassNew {
    MyClassNew(ParamObject p) {}
}

public class MyChildClassNew {
    MyChildClassNew(ParamObject p) { super(p); }
}

Now you can add a builder pattern for ParamObject to make constructing ParamObject easier.