E10.7 In Worked Example 10.1, make the process method a default method of the Sequence interface.

Worked Example 10.1 (four classes and an interface)

1)

/** This class analyzes the distribution of the last digit of values from a sequence. */ public class LastDigitDistribution { private int[] counters;

/** Constructs a distribution whose counters are set to zero. */ public LastDigitDistribution() { counters = new int[10]; }

/** Processes values from this sequence. @param seq the sequence from which to obtain the values @param valuesToProcess the number of values to process */ public void process(Sequence seq, int valuesToProcess) { for (int i = 1; i <= valuesToProcess; i++) { int value = seq.next(); int lastDigit = value % 10; counters[lastDigit]++; } }

/** Displays the counter values of this distribution. */ public void display() { for (int i = 0; i < counters.length; i++) { System.out.println(i + ": " + counters[i]); } } }

2)

public class RandomSequence implements Sequence { public int next() { return (int) (Integer.MAX_VALUE * Math.random()); } }

3)

public interface Sequence { int next(); public void process(Sequence seq, int valuesToProcess); }

4)

public class SequenceDemo { public static void main(String[] args) { LastDigitDistribution dist1 = new LastDigitDistribution(); dist1.process(new SquareSequence(), 1000); dist1.display(); System.out.println();

LastDigitDistribution dist2 = new LastDigitDistribution(); dist2.process(new RandomSequence(), 1000); dist2.display(); } }

5)

public class SquareSequence implements Sequence { private int n;

public int next() { n++; return n * n; } }