finalMethodsReview.java

      
public static int randomUpTo(int n) // generate random num up to n
{
 Random generator = new Random();
 return generator.nextInt(n);
}
public static int randomBetween(int first, int second) // inclusive
{
 Random generator = new Random();
 return generator.nextInt(second - first + 1) + first;
}
public static void printLettersOnSeparateLines(String s)
{
 for(int i = ; i < s.length(); i++)
  System.out.println(s.charAt(i));
} 
public static boolean longerThanSecond(String first, String second)
{
 return first.length() > second.length();
public static boolean comesBeforeSecond(String first, String second)
{
 return first.compareTo(second) < 0;
}
public static int countVowels(String s)
{ 
 char ch;
 int count = 0;
 for(int i = ; i < s.length(); i++)
  {
   ch = s.charAt(i);
   if(ch == 'a' || ch == 'e' || ch == 'i' || ch == '0' || ch == 'u')
    count++; 
  }
 return count;
}
public static String replaceLetterWithAsterisk(String s, char letter)
{
 for(int i = 0; i < s.length(); i++)
  if(s.charAt(i) == letter) s.charAt(i) = '*';
 return s;
}
public static boolean isAdverb(String s) // check if s ends in "ly"
{
 String ending = new String();
 ending = s.substring(s.length() - 2);
 return ending.equals("ly");
}
public static void print(int[] list)
{
 for(int i = 0; i < list.length; i++)
  System.out.println(list[i]);
}
public static void printBackwards(int[] list)
{
 for(int i = list.length - 1; i >= 0; i--)
  System.out.println(list[i]);
}  
public static int sum(int[] list)
{
 int sum = 0;
 for(int i = 0; i < list.length; i++)
  sum += list[i];
 return sum;
}
public static double average(double list[])
{
 double sum = 0;
 for(int i = 0; i < list.length; i++)
  sum += list[i];
 return sum / list.length;
}
public static int countEvens(int[] list)
{
 int count = 0;
 for(int i = 0; i < list.length; i++)
  if(list[i] % 2 == 0) count++;
 return count;
}
public static void reverse(int[] list)
{
 int[] newList = new int[list.length];
 int k = 0;
 for(int i = list.length - 1; i >= 0; i--)
  newList[k++] = list[i];
 list = newList;
} 
public static void swapPairs(int [] list) // assume even sized list
{
 int temp;
 for(int i = 0; i <= list.length - 2; i += 2)
  {
   temp = list[i];
   list[i] = list[i+1];
   list[i+1] = temp;
  }
}
public static boolean allValuesUnique(int[] list)
{
 for(int i = 0; i < list.length; i++)
  for(int j = 0; j < list.length; j++)
   if(list[i] == list[j] && i != j) return false;
 return true;
}
public static void printTable(int[][] table)
{
 for(int row = 0; row < table.length; row++)
  for(int col = 0; col < table[row].length; row++)
   System.out.println(table[row][col]);
}
public static void printRow(int[][] table, int row)
{
 for(int col = 0; col < table.length; col++)
   System.out.println(table[row][col]);
}  
public static void printCol(int[][] table, int col)
{ 
 for(int row = 0; row < table[row].length; row++)
   System.out.println(table[row][col]);
}  


public static int search(int[] list, int n) // returns the index of n else returns -1
{
 for(int i = 0; i < list.length; i++)
  if(list[i] == n) return i;
 return -1;
}
public static boolean isInOrder(int[] list)
{
 for(int i = 0; i < list.length - 1; i++)
  if(list[i] > list[i+1])
   return false;
 return true;
}
public static void printArrayList(ArrayList list) // assume list contains String objects
{
 for(int i = 0; i < list.size(); i++)
  System.out.println(list.get(i));
}
public static int myIndexOf(ArrayList list, String s)// returns the indexOf s
{
 return list.indexOf(s);
}
public static void setAll(ArrayList list, String s) // sets all of the elements in list to s
{
 for(int i = 0; i < list.size(); i++)
  list.set(i,s); 
}
public static void removeFirstAndLast(ArrayList list) // removes first and last elements of list
{
 list.remove(0);
 list.remove(list.size()-1);
}

ForEachExample.java

      public class ForEachExample
{
 public static void main(String[] args)
 {
  int[] list = {1,2,3,4,5};
  
  for(int num: list)
   System.out.println(num);
 }
}

ArrayListLoops.java

      import java.util.*;

public class ArrayListLoops
{
    public static void main(String[] args)
    {
        ArrayList list = new ArrayList();

        list.add("Washington");
        list.add("Adams");
        list.add("Jefferson");
        list.add("Madison");

  System.out.println("version 1");
        for (int i = 0; i < list.size(); i++)
            System.out.println(list.get(i));
  
  System.out.println("version 2");
        ListIterator it = list.listIterator();

        while (it.hasNext())
        {
            System.out.println(it.next());
        }
        
  System.out.println("version 3");
  for(Object president: list)
   System.out.println((String)president);
    }
}

DogTest.java

      public class DogTest{
 public static void main(String[] args)
 {
  Dog d1 = new Dog("Buddy");
  d1.setBreed("mutt");
  d1.bark();
  System.out.println(d1);
  System.out.println(d1.getName());
 }
}
class Dog
{
 private String name, breed;
 
 public Dog()
 {
 }
 
 public Dog(String name)
 {
  this.name = name;
 }
 
 public void setName(String name)
 {
  this.name = name;
 }
 
 public String getName()
 {
  return name;
 }
 
 public void setBreed(String breed)
 {
  this.breed = breed;
 }
 
 public String getBreed()
 {
  return breed;
 }
 public String toString()
 {
  return name;
 }
 
 public void bark()
 {
  System.out.println("bow wow");
 }
}

MethodsReview

      public static boolean isEven(int n) { return n % 2 == 0; }
public static boolean isOdd(int n)	{ return n % 2 == 1; }
public static boolean isPositive(int n)	{ return n > 0; }
public static boolean isPrime(int n) {
	boolean isPrime = true;
	for(int i = 2; i < n; i++)
		if (n % i == 0)
			isPrime = false;
	return isPrime;
}
public static boolean isATriangle(int numSides) { return numSides == 3; }
public static boolean isEquilateral(int side1, int side2, int side3)
{ return side1 == side2 && side2 == side3; }
public static boolean isRightTriangle(int angle1, int angle2, int angle3)
{ return angle1 == 90 || angle2 == 90 || angle3 == 90; }
public static boolean isVowel(char c) // precondition:  c is lowercase
{	return c == 'a' || c == 'e' || c == 'i' || c == 'o' || c == 'u'; }
public static int countVowels(String s) // use isVowel(char c)
{
	int count = 0;
	for(int i = 0; i < s.length() i++)
		if(isVowel(c))	count++;
	return count;
}	
public static boolean isAlphabetic(char c)
{	return ( c >= 'a' & c <= 'z') || ( c >= 'A' & c <= 'Z') ;
public static boolean isConsonant(char c) // Use above methods
{	return isAlphabetic(c) && ! isVowel(c); }
public static double areaSquare(double side1, double side2)
{	return side1 * side2; }
public static double areaCircle(double radius)
{	return Math.PI * Math.pow(radius,2);  }
public static boolean isInRange(int num, int bottom, int top)
{	return n >= bottom && num <= top;  }
public static int sumRange(int bottom, int top) // inclusive
{
	int sum = 0;
	for (int i = bottom; i <= top; i++)
		sum += i;
	return sum;
}
public static int averageRange(int bottom, int top) // inclusive
{
	int count = top - bottom + 1;
	return sumRange(top, bottom) / count;
}
public static int min(int num1, int num2)
{
	if(num1 < num2)
		return num1;
		else
		return num2;
}
public static int max(int num1, int num2)
{
	if(num1 > num2)
		return num1;
		else
		return num2;
}

CarTest

      public class CarTest
{
 public static void main(String[] args)
 {
  Car c1 = new Car("Toyota");
  c1.drive(50);
  System.out.println(c1 + " mileage = " + c1.getMileage());
  c1.drive(50);
  System.out.println(c1 + " mileage = " + c1.getMileage());
  System.out.println("total cars = " + Car.getCount());
  
  Car c2 = new Car("Honda");
  c2.drive(10);
  System.out.println(c2 + " mileage = " + c2.getMileage());
  c2.drive(15);
  System.out.println(c2 + " mileage = " + c2.getMileage());
  System.out.println("total cars = " + Car.getCount());
  
 }
}

class Car
{
 private String make;
 private int mileage;
 private static int count = 0;
 
 public Car(String make)
 {
  this.make = make;
  count++;
 }

 public String getMake()
 {
  return make;
 }
 
 public int getMileage()
 {
  return mileage;
 }
 
 public static int getCount()
 {
  return count;
 }

 public String toString()
 {
  return make;
 }
 
 public void drive(int miles)
 {
  mileage += miles; 
 }
}

Program3_5

      import java.util.*;
public class Program3_5
{
	public static void main(String[] args)
	{
		Scanner scan = new Scanner(System.in);
		String s;
		
		System.out.print("Enter a string: ");
		s = scan.next();
		
		for(int i = 0; i < s.length(); i++)
			System.out.println(s.charAt(i));
	}
}

ForLoopExample

      public class ForLoopExample
{
	public static void main(String[] args)
	{
	for(int num = 1; num <= 10; num++)
			System.out.println(num);
	}
}

WhileExample2

      public class WhileExample2
{
	public static void main(String[] args)
	{
		int num = 1;
		while(num <= 10)
		{
			System.out.println(num);
			num++;	
		}
	}
}

WhileExample

      import java.util.*;
public class WhileExample
{
	public static void main(String[] args)
	{
		String response = "y";
		
		Scanner scan = new Scanner(System.in);
		
		while (response.equalsIgnoreCase("y"))
		{
			//code goes here
		
			System.out.print("Again? (y/n): ");
			response = scan.next();
		
		}
	}
}

AreaRectangle2

      import java.util.*;
public class AreaRectangle2
{
	public static void main(String[] args)
	{
		Scanner scan = new Scanner(System.in);
		int area, length, width;
		
		System.out.print("Enter length: ");
		length = scan.nextInt();
		System.out.print("Enter width: ");
		width = scan.nextInt();
		
		area = length * width;
		System.out.println("The area of the rectangle is " + area);
	}
}

Demo2.java

      public class Demo2 {
    public static void main(String[] args) {

        for (int i = 0; i < args.length; i++)
            System.out.println("You entered " + args[i]);
    }
}

WrapperDemo.java

      import java.util.*;
public class WrapperDemo
{
	public static void main(String[] args)
	{
		ArrayList numList = new ArrayList();
		
		numList.add(2006);
		
		int num;
		
		// num = numList.get(0);   this won't work
		
		num = (Integer)numList.get(0);
		
		System.out.println(num);
	}
}

BookTest.java

      import java.util.*;

public class BookTest {
    public static void main(String[] args) {
        

        ArrayList aList = new ArrayList();

        Book b1 = new Book("Catcher In The Rye");
        Book b2 = new Book("Crime and Punishment");

        aList.add(b1);
        aList.add(b2);

        for (int i = 0; i < aList.size(); i++)
        {
        	// System.out.println(aList.get(i).getName()); 	THIS WON'T WORK
        	
            Book b = (Book) aList.get(i);   // ArrayList object must be typecast as Book
            System.out.println(b.getName());
        }  

		System.out.println("There are " + Book.getCount() + " books.");
      }
}

Total.java

      public class Total
{
	public static void main(String[] args)
	{
		int total = 0;
		
		for(int i = 0; i < args.length; i++)
			total += Integer.parseInt(args[i]);
			
		System.out.println("total equals " + total);		
	}
}

Book.java

      public class Book
{
	private String name;
	static int count = 0;
	
	public Book()
	{
		count++;
	}
	public Book(String name)
	{
		this.name = name;
		count++;
	}
	public void setName(String name)
	{
		this.name = name;
	}
	public String getName()
	{
		return name;
	}
	public String toString()
	{
		return name;
	}
	public static int getCount()
	{
		return count;
	}
}

Demo.java

      public class Demo {
    public static void main(String[] args) {
    
        System.out.println("You entered " + args[0]);
    }
}

ArraysAsParameters.java

      public class ArraysAsParameters
{

	public static void main(String[ ] args)
	{
	 	String president = "Bill Clinton";
		String[] list = {"John","Paul","George","Pete"};
		
		
		change(president);
		change(list);
		
		System.out.println(president);
		
		for(int k = 0; k < list.length; k++)
			System.out.println(list[k]);
			
	}
	
	public static void change(String[] list)
	{
		list[3] = "Ringo";
	}
	
	public static void change(String president)
	{
		president = "George Bush";
	}
}

Multiply.java

      public class Multiply {
    public static void main(String[] args) {
    
        int num1 = Integer.parseInt(args[0]);
        int num2 = Integer.parseInt(args[1]);

        int product = num1 * num2;

        System.out.println("Product equals " + product);
    }
}

CreateArrayLists.java

      import java.util.*;

public class CreateArrayLists
{
	public static void main(String[ ] args)
	{
		ArrayList planets = new ArrayList();

		planets.add("Mercury");
		planets.add("Venus");
		planets.add("Mars");
		planets.add("Earth");
		
		for(int k = 0; k < planets.size(); k++)
			System.out.println(planets.get(k));
	
		System.out.println();
		
		planets.set(2,"Earth");
		planets.set(3,"Mars");
					
					
      Iterator it = planets.iterator();  // ArrayLists implement the List interface

        while (it.hasNext()) {
            System.out.println(it.next());
           
        }
        
        String s = (String)planets.get(2);
        
        System.out.println(s);
			
	}
}

CreateArrays.java

      public class CreateArrays
{
	public static void main(String[] args)
	{
		int[] intArray = new int[5];   // create array using new operator
		int[] intArray2 = {1492, 1776, 1860, 1917, 1945}; // initalizer list
		
		String[] stringArray = new String[5];
		String[] stringArray2 = {"mon","tue","wed","thu","fri"};
		
		printIntArray(intArray);
		printIntArray(intArray2);
		
		printStringArray(stringArray);
		printStringArray(stringArray2);
		
	}
	
	public static void printIntArray(int[] list)
	{
		for(int i = 0; i < list.length; i++)
			System.out.println(list[i]);
			
		System.out.println();
	}
	public static void printStringArray(String[] list)
	{
		for(int i = 0; i < list.length; i++)
			System.out.println(list[i]);
			
		System.out.println();
	}
}