1. public class Date {
       private int month;
       private int day;
       private int year;
   
       public Date()
       {
   	month = 1;
   	day = 1;
   	year = 1996;
       }
       public Date(int mon, int dy, int yr)
       {
   	month = mon;
   	day = dy;
   	year = yr;
       }
       public Date nextDay()
       {
   	Date next = new Date();
   	next.month = month;
   	next.day = day;
   	next.year = year;
   	if (month == 2)
   	    if (day < 28)
   		next.day++;
   	    else
   	    {
   		next.day = 1;
   		next.month = 3;
   	    }
   	else if (month == 4 || month == 6 || month == 9 || month == 11)
   	    if (day < 30) 
   		next.day++;
   	    else
   	    {
   		next.day = 1;
   		next.month = month++;
   	    }
   	else if (month == 12 && day == 31)
   	{
   	    next.month = 1;
   	    next.day = 1;
   	    next.year++;
   	}
   	else
   	    if (day < 31)
   		next.day++;
   	    else
   	    {
   		next.day = 1;
   		next.month = month++;
   	    }
   	return next;
       }
       public boolean before(Date second)
       {
   	if (second.year < year)
   	    return false;
   	if (second.year > year)
   	    return true;
   	if (second.month < month)
   	    return false;
   	if (second.month > month)
   	    return true;
   	if (second.day < day)
   	    return false;
   	if (second.day > day)
   	    return true;
   	return false;
       }
       public String toString()
       {
   	String hold;
   	hold = Integer.toString(month) + "/" + Integer.toString(day) + "/" + 
   						  Integer.toString(year);
   	return hold;
       }
   }
   
   

2. import java.io.PrintWriter;
   public class DateTest	{
       public static void main(String[] args)
       {
   	PrintWriter stdout = new PrintWriter(System.out,true);
   	Date first = new Date();
   	Date next = new Date(10,26,99);
   	Date later = next.nextDay().nextDay();
   	Date mine = new Date(11,29,99);
   	if (first.before(mine))
   	    stdout.println("Earlier");
   	else
   	    stdout.println("Later");
   	Date [] theDates = new Date[10];
   	theDates[0] = new Date(4,1,99);
   	theDates[1] = new Date(5,1,99);
   	theDates[2] = new Date(6,1,99);
   	for (int i = 0 ; i < 3 ; i++)
   	    stdout.println(theDates[i]);
       }
   }
   
   

3.     public class StringOps
       {
   	public static int countChar(String str, char find)
   	{
   	    int count = 0;
   	    for (int i = 0 ; i < str.length() ; i++)
   		if (str.charAt(i) == find)
   		    count++;
   	    return count;
   	}
   	public static String removeChar(String str, char remove)
   	{
   	    char hold;
   	    StringBuffer remstr = new StringBuffer();
   	    for (int i = 0 ; i < str.length() ; i++)
   	    {
   		hold = str.charAt(i);
   		if (hold != remove)
   		    remstr.append(hold);
   	    }
   	    String retstr = new String(remstr);
   	    return retstr;
   	}
       }
   
   

4. import java.io.PrintWriter;
   public class StringTest {
       public static void main(String[] args) {
   	PrintWriter stdout = new PrintWriter(System.out,true);
   	String road = "The road goes ever on and on";
   	int nume = StringOps.countChar(road,'e');
   	stdout.println("There are " + nume + "e's in the String.");
   	String nors = StringOps.removeChar(road,'r');
   	stdout.println("After removing r's the String is: " + nors);
       }
   }
   
   

5. import java.io.PrintWriter;
   
   public class Person {
       protected String name;
       protected String address;
   
       public Person() { }
       public Person(String nn,String aa) {
   	name = new String(nn);
   	address = new String(aa);
       }
       public void print() {
       	PrintWriter stdout = new PrintWriter(System.out,true);
   	stdout.println("Name:    " + name);
   	stdout.println("Address: " + address + "\n");
       }
   
   public class Employee extends Person {
       protected long SSN;
       protected int salary;
   
       public Employee() { }
       public Employee(String nn,String aa,long snum,int sal) {
   	super(nn,aa);
   	SSN = snum;
   	salary = sal;
       }
       public void print() {
   	PrintWriter stdout = new PrintWriter(System.out,true);
   	stdout.println("Name:    " + name);
   	stdout.println("Address: " + address);
   	stdout.println("SSN:     " + SSN);
   	stdout.println("Salary   " + salary + "\n");
       }
       public void raise(int percent) {
   	salary = salary + (int)(salary * percent * .01);
       }
   }
   
   

6. 1.  valid
   2.  valid
   3.  valid
   4.  invalid, because you cannot have a subclass reference point to a 
       superclass object 
   
   

7. import java.io.PrintWriter;
   public class PerEmplTest {
       public static void main(String[] args) {
      	Person [] list = new Person[4];
   	list[0] = new Person("Sam", "Bagshot Row");
   	list[1] = new Person("Saruman","Orthanc");
   	list[2] = new Employee("Merry","Buckland",111223333,62500);
   	list[3] = new Employee("Pippin","Great Smials",222334444,64000);
   	for (int i = 0 ; i < list.length ; i++)
   	    list[i].print();
       }
   }
   
   

8.         Name:    Sam
   	Address: Bagshot Row
   
   	Name:    Saruman
   	Address: Orthanc
   
   	Name:    Merry
   	Address: Buckland
   	SSN:     111223333
   	Salary   62500
   
   	Name:    Pippin
   	Address: Great Smials
   	SSN:     222334444
   	Salary   64000
   
   

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