Create an interface Measurable that has a single method: int getMeasure()

Rewrite our old friend DataSetBook. Change its name to DataSetMeasurable. Replace all references to Book objects with Measurable objects.

To test your DataSetMeasurable, write two or more classes that implement Measurable. (I suggest keeping them very simple.) Write a tester that puts instances of both Measurable classes into a DataSetMeasurable.

Notice that DataSetBook could store only Book objects. But DataSetMeasurable can store anything implementing Measurable. If I have a Building class implementing Measurable, and a HeatSensor implementing Measurable, I can put Buildings and HeatSensors into one DataSetMeasurable object. Doing that probably isn't rational, but DataSetMeasurable is much more flexible than DataSetBook; so long as the objects we add to it are Measurable, it doesn't care if the application using it is sensible or not.

The starter file is the same one from our Inheritance lesson. You may start with this starter code or may start from your solution to the Inheritance lab. Either is acceptable.

we have already thoes cods :

package lab_start;

public class Book { private String author; private String title; private int pages;

public Book(String auth, String titl, int pag) { author = auth; title = titl; pages = pag; }

public int getPages() { return pages; }

@Override public String toString() { return "Book [author=" + author + ", title=" + title + ", pages=" + pages + "] "; }

@Override public boolean equals(Object obj) { if (this == obj) return true; if (obj == null) return false; if (getClass() != obj.getClass()) return false; Book other = (Book) obj; if (author == null) { if (other.author != null) return false; } else if (!author.equals(other.author)) return false; if (pages != other.pages) return false; if (title == null) { if (other.title != null) return false; } else if (!title.equals(other.title)) return false; return true; }

}

package lab_start;

import java.util.ArrayList;

public class DataSetBook { private ArrayList data;

public DataSetBook() { data = new ArrayList<>(); } public boolean add(Book objToAdd) { return data.add(objToAdd); } public int size() { return data.size(); } public Book getMin() { if (data.isEmpty()) { return null; } Book mEle = data.get(0); for (int i = 1; i < data.size(); i++) { if (mEle.getPages() > (data.get(i).getPages())) { mEle = data.get(i); } } return mEle; }

public Book getMax() { if (data.isEmpty()) { return null; } Book mEle = data.get(0); for (int i = 1; i < data.size(); i++) { if (mEle.getPages() < (data.get(i).getPages())) { mEle = data.get(i); } } return mEle; }

@Override public String toString() { return "DataSetBook [ size()=" + size() + " getMin()=" + getMin() + " getMax()=" + getMax() + " Books= " + data.toString() + "]"; } }