Java Codelab: 1.2 Built-in Data Types

Java Codelab

1.2 Built-in Data Types

¤ Integers

· Literals

Write a literal representing the integer value zero.

0

Write a literal representing the long integer value twelve billion.

12000000000l

Write a hexadecimal integer literal representing the value fifteen.

0xF

· Constants 

Declare an integer constant,  MONTHS_IN_YEAR , whose value is  12 .

final int MONTHS_IN_YEAR = 12 ;

 Declare a constant MONTHS_IN_DECADE , whose value is the value of the constant  MONTHS_IN_YEAR (already declared) multiplied by  10 .

final int MONTHS_IN_DECADE  = MONTHS_IN_YEAR * 10 ;

Declarations

Declare an integer variable named  degreesCelsius .

int degreesCelsius;

Declare a short variable named  patientsAge .

short patientsAge

Declare a long integer variable named  grossNationalProduct .

long grossNationalProduct ;

Declare two integer variables named  profitStartOfQuarter and  cashFlowEndOfYear .

int profitStartOfQuarter, cashFlowEndOfYear ;

Declare and initialize the following variables:
 · monthOfYear , initialized to the value 11
 · companyRevenue , initialized to the value 5666777
 · firstClassTicketPrice , initialized to the value 6000
 · totalPopulation , initialized to the value 1222333

int monthOfYear = 11;
int companyRevenue = 5666777;
int firstClassTicketPrice = 6000;
int totalPopulation = 1222333;

· Operations

Write an expression that computes the sum of two variables  verbalScore and  mathScore (already declared and assigned values).

verbalScore + mathScore

Given the variables  taxablePurchases and  taxFreePurchases (already declared and assigned values), write an expression corresponding to the total amount purchased.

taxablePurchases + taxFreePurchases

Write an expression that computes the difference of the variables  endingTime and  startingTime .

endingTime - startingTime

Given the variables  fullAdmissionPrice and  discountAmount (already declared and assigned values), write an expression corresponding to the price of a discount admission.

fullAdmissionPrice - discountAmount

Given the variable  pricePerCase , write an expression corresponding to the price of a dozen cases.

pricePerCase * 12


Given the variables  costOfBusRental and  maxBusRiders of type  int , write an expression corresponding to the cost per rider (assuming the bus is full). (Do not worry about any fractional part of the expression-- let integer arithmetic, with truncation, act here.)

costOfBusRental / maxBusRiders


Write an expression that computes the remainder of the variable  principal when divided by the variable  divisor . (Assume both are type  int .)

principal % divisor

· Precedence

Write an expression that computes the average of the values  12 and  40 .

(12 + 40) / 2

Write an expression that computes the integer average of the int variables  exam1 and  exam2 (both declared and assigned values).

(exam1 + exam2) /2

¤ Floating Point

· Literals

Write a literal corresponding to the floating point value one-and-a-half.

1.5

Write a literal corresponding to the value of the first 6 digits of PI ("three point one four one five nine").

3.14159

·Declarations

Declare a  float variable named  price .

float price ;

Declare a  double variable named  netWeight . 

double netWeight ;


 Declare two  double variables, one named  length with a value of  3.5 and the other named  width with a value of  1.55 .

double length = 3.5, width = 1.55 ;

·Operations

Write an expression that computes the sum of two  double variables  total1 and  total2 , which have been already declared and assigned values.

total1 + total2

 Write an expression that computes the difference of two  double variables  salesSummer and  salesSpring , which have been already declared and assigned values. 

salesSummer - salesSpring

You are given two  double variables, already declared and assigned values, named  totalWeight , containing the weight of a shipment, and  weightOfBox , containing the weight of the box in which a product is shipped. Write an expression that calculates the net weight of the product.

totalWeight - weightOfBox

You are given two variables, already declared and assigned values, one of type  double , named  totalWeight , containing the weight of a shipment, and the other of type  int , named  quantity , containing the number of items in the shipment. Write an expression that calculates the weight of one item.

totalWeight / quantity

You are given two variables, already declared and assigned values, one of type  double , named  price , containing the price of an order, and the other of type  int , named  totalNumber , containing the number of orders. Write an expression that calculates the total price for all orders.

price * totalNumber

Java Codelab: 1.1 Your first program

Java Codelab

1.1 Your first program

Write a statement that prints  Hello, world to the screen.

System.out.println("Hello, world");

 Write a complete main  method that prints  Hello, world to the screen.  

public static void main(String[]args){
System.out.println("Hello, world");
}

 Suppose your name was Alan Turing. Write a statement that would print your last name, followed by a comma, followed by a space and your first name.  

System.out.print("Turing, Alan");

Suppose your name was George Gershwin. Write a complete main method that would print your last name, followed by a comma, followed by a space and your first name. 

public static void main(String[]args){
System.out.println("Gershwin, George");
}

Write a complete program whose class name is Hello and that displays  Hello, world on the screen.

public class Hello {
public static void main(String[]args){
System.out.println("Hello, world");
}
}