package my.groovy.category;

import java.math.BigDecimal;
import java.math.BigInteger;

public class MyNumberCategory {
    /** A singleton Number instance to guarantee an exactly traceable return
     *  value for demonstrating the category method overriding issue. 
     */
    public static final Number POW_RETURN = Double.valueOf( 1.2345 );

    // When the base value is a Number sub-class that has a pow(int) method
    // (like BigDecimal or BigInteger), this method is not called in Groovy 1.5,
    // but was in Groovy 1.0. 
    //
    // The Groovy 1.0 behavior seems to be the desired behavior, you would like
    // to be able to have a category method augmenting all sub-classes of a
    // parent class (or interface even).  I did notice that Groovy 1.0 won't
    // work if the first argument of the category method is an interface type
    // versus a parent class.
    //
    public static Number pow( final Number base, final int exp ) {
        return POW_RETURN;
    }

    // Uncomment this method and the category works for instances of BigDecimal in Groovy 1.5
//    public static Number pow( final BigDecimal base, final int exp ) {
//        return POW_RETURN;
//    }

    // Uncomment this method and the category works for instances of BigInteger in Groovy 1.5
//    public static Number pow( final BigInteger base, final int exp ) {
//        return POW_RETURN;
//    }
}