So Many Things Forgotten

 I have an ArrayList<ArgTypes> 

public class ArgTypes 

{

// Instance

String argName;

ArgValueTypes argumentValueType;

double doubleValue;

boolean booleanValue;

int intValue;

// Constructor of each pair

public ArgTypes (String inputArgName, ArgValueTypes inputArgumentValueType, double target)

{

this.argName = inputArgName;

this.argumentValueType = inputArgumentValueType;

this.doubleValue = target;

}

};

doubleValy, booleanValue, and intValue in my C implementation of this code are a union that is a pointer to various variables.  My goal is to Double.ParseDouble a String and store the double into a variable for later reference.  In C, I store a double* and then use indirection to store the value where I want it.  What is the equivalent in Java.  Is there one?