Functional Composition in Java ver. 1

AbstractFunction.java

package functionalcomposition;

public abstract class AbstractFunction implements Function {
    @Override
    public Function compose(final Function f) {
        return new AbstractFunction() {
            @Override
            public double apply(double x) {
                return AbstractFunction.this.apply(f.apply(x));
            }
        };
    }

    @Override
    public abstract double apply(double x);
}

Function.java

package functionalcomposition;

public interface Function {
    Function compose(Function f);
    double apply(double x);
}

Main.java

package functionalcomposition;

public class Main {
    public static void main(String[] args) {
        Function f = new AbstractFunction() {
            @Override
            public double apply(double x) {
                return Math.exp(x);
            }
        };
        Function g = new AbstractFunction() {
            @Override
            public double apply(double x) {
                return Math.pow(x, 2);
            }
        };
        Function h = new AbstractFunction() {
            @Override
            public double apply(double x) {
                return -x+1;
            }
        };

        Function composed = f.compose(g).compose(h);
        System.out.println(composed.apply(10));
    }
}