Consider the following partially complete class: public class TestClass implemen
ID: 3735209 • Letter: C
Question
Consider the following partially complete class:
public class TestClass implements Comparable {
private String lastName;
private String firstName
public TestClass( String lastName, String firstName )
{
this.lastName = lastName;
this.firstName = firstName;
}
public String getLastName()
{
return this.lastName;
}
public String getFirstName()
{
return this.firstName;
}
public int compareTo( Object obj )
{
// complete the code here
}
}
Using the Comparable interface, write a compareTo( ) method that returns -1 if the private instance variable firstName occurs lexicographically before obj, 0 if the private instance variable firstName and obj are lexicographically the same, or 1 if the private instance variable firstName occurs lexicographically after obj. Use a getter method any time you need to use a private instance variable.
Explanation / Answer
TestClass.java
public class TestClass implements Comparable {
private String lastName;
private String firstName;
public TestClass( String lastName, String firstName )
{
this.lastName = lastName;
this.firstName = firstName;
}
public String getLastName()
{
return this.lastName;
}
public String getFirstName()
{
return this.firstName;
}
public int compareTo( Object obj )
{
// complete the code here
if(firstName.compareTo(((TestClass)obj).getFirstName()) > 0) {
return 1;
} else if(firstName.compareTo(((TestClass)obj).getFirstName()) < 0) {
return -1;
} else {
return 0;
}
}
}