public class Book
{
private String name;
private String isbnNumber;
public Book(String name, String isbnNumber)
{
super();
this.name = name;
this.isbnNumber = isbnNumber;
}
public String getName()
{
return name;
}
public void setName(String name)
{
this.name = name;
}
public String getIsbnNumber()
{
return isbnNumber;
}
public void setIsbnNumber(String isbnNumber)
{
this.isbnNumber = isbnNumber;
}
@Override
public int hashCode()
{
final int prime = 31;
int result = 1;
result = prime * result
+ ((isbnNumber == null) ? 0 : isbnNumber.hashCode());
return result;
}
@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 (isbnNumber == null)
{
if (other.isbnNumber != null)
return false;
}
else if (!isbnNumber.equals(other.isbnNumber))
return false;
return true;
}
}
public class ObjectClassTest
{
public static void main(String[] args)
{
Book childrenStoryBook = new Book("Children Story",
"2000");
Book KidStoryBook = new Book("Kids Story", "2000");
System.out.println("childrenStoryBook.hashCode = "+childrenStoryBook.hashCode());
System.out.println("KidStoryBook.hashCode = "+KidStoryBook.hashCode());
/*
* This program displays objects are equal even
* though childrenStoryBook and KidStoryBook
* reference two distinct objects. They are
* considered equal because the objects compared
* contain the same ISBN number.
*/
if (childrenStoryBook.equals(KidStoryBook))
{
System.out.println("objects are equal");
}
else
{
System.out.println("objects are not equal");
}
}
}
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