CMPT 125: Lecture 3 Data and Expressions

Save this PDF as:

Size: px
Start display at page:

Download "CMPT 125: Lecture 3 Data and Expressions"

Transcription

1 CMPT 125: Lecture 3 Data and Expressions Tamara Smyth, School of Computing Science, Simon Fraser University January 3,

2 Character Strings A character string is an object in Java, defined by the class String. Because they are used so frequently, Java allows the use of string literals, delimited by double quotes ("). We will return to the String class, for now let s look more closely at string literals. A string literal may include any valid character: "I like eggs and ham!" or no characters at all: "" CMPT 125: Data and Expressions, Lecture 3 2

3 The print and println Methods Recall from the program WiseWords, we invoked the println method as follows: System.out.println("No matter where you go..."); System.out.println("... there you are."); System.out represents an output device, or file, which by default is the monitor screen. The object s name is out and it is stored in the System class. The method println prints a character string to the screen. Each piece of data is sent to a method is called a parameter. The println takes a single parameter which is a character string. The print method is very similar to println but does not move to the beginning of a new line when completed. CMPT 125: Data and Expressions, Lecture 3 3

4 String Concatenation A string literal may not span multiple lines. //The following statement will not compile System.out.println("It was the best of times, it was the worst of times, it was the age of wisdom, it was the age of foolishness, it was the epoch of disbelief, it was the epoch of incredulity,..."); Use + to append, or concatenate one string to another: If you use an integer literal in a string concatenation, it will automatically convert 100 to 100. System.out.println("This is probably one of the longest " + "sentences ever to open novel. " + "It uses over " " words."); OUTPUT: This is probably one of the longest sentences ever to open a novel. It uses over 100 words. CMPT 125: Data and Expressions, Lecture 3 4

5 Concatenation vs. Arithmetic Addition Of course, the + operator is also used for arithmetic addition. The action performed by + depends on the data type of the parameter on which it operates. CODE: public class AdditionDemo { //The difference between concatenation and //arithmetic addition System.out.println("2 and 2 concatenated: " ); System.out.println("2 and 2 added: " + (2 + 2)); OUTPUT: 2 and 2 concatenated: 22 2 and 2 added: 4 First call to println: performs concatenation since operators are executed left to right. Second call to println: the parenthesis groups two numeric operands, (2+2), forcing this operation (addition) to happen first. This result, 4, is then concatenated with the preceding string. CMPT 125: Data and Expressions, Lecture 3 5

6 Escape Sequences An escape sequence can be used to represent a character that would otherwise cause compilation error. Eg: since Java uses the double quotation character (\") to represent a string, we must used an escape sequence if we wish to print this character type without confusing the compiler. System.out.println("This is a demonstration " + "of how \"Escape Sequences\" can be used \n" + "within a string literal to print on a diagonal: \n" + "one\n\t two\n\t\t three\n\t\t\t four\n\t\t\t\t five"); } }; OUTPUT: This is a demonstration of how Escape "Sequences" can be used within a string literal to print on a diagonal: one two three four five CMPT 125: Data and Expressions, Lecture 3 6

7 Java defines several Escape Sequences for printing special characters in string literals. Escape Sequence Meaning \b backspace \t tab \n newline \r carriage return \" double quote \ single quote \\ backlash CMPT 125: Data and Expressions, Lecture 3 7

8 Variables and Assignments A variable is a name for a location in memory used to hold a value of a particular data type. int x = 6; double cc1 = -2.1; 6 x 2.1 cc1 Figure 1: Variables that hold primitive values are like buckets A variable declaration instructs the compiler to reserve enough main memory space to hold that value type, and assigns a name by which we may refer to that location. CMPT 125: Data and Expressions, Lecture 3 8

9 Variable Declaration Each variable declaration consists of a type followed by a Variable Declarator. Type Variable Declarator int year = 2006; Identifier assignment operator value Figure 2: Variable Declaration. A variable declaration may consist of several variables of the same type, and may, or may not, include an initializing value: String yourname, myname = "Larry"; int count, minimum = 0, result; double rate; CMPT 125: Data and Expressions, Lecture 3 9

10 Assignment Statements It is an error to reference (or use) a variable before it is assigned a value (or initialized). A variable may be assigned a value using an assignment statement: rate = 0.5; When executed, the RHS of the assignment operator (=), is stored in the memory location indicated by the identifier. Identifier = Expression ; Figure 3: Basic Assignment. CMPT 125: Data and Expressions, Lecture 3 10

11 Changing a Variable Value A variable can store only one value of its declared type. A new assignment statement overwrites an old value. public class MySum { public static void main (String[] args) { int sum; sum = 7; sum = sum + 3; System.out.println( The sum is: + sum); } } OUTPUT: The sum is: 10 Java is strongly typed, meaning we cannot assign a value of one type to a variable of an incompatible type. CMPT 125: Data and Expressions, Lecture 3 11

12 Declaring Constants When values that do not change are used throughout a program, it is more meaningful to the programmer to give them names, rather than using a literal values. Constants are similar to variables, but they hold a particular value for the duration of their existence they cannot be changed. Constants are created by preceding the declaration with the final modifier. final double MAX_RATE = 0.07; It is conventional to use all uppercase letters for constant identifiers. CMPT 125: Data and Expressions, Lecture 3 12

13 Primitive Data Types Java distinguishes between two types of data 1. Primitive data: holds a value 2. Objects: holds a reference There are eight primitive data types in Java: four (4) subsets of integers two (2) subsets of floating point numbers a character data type a boolean data type Everything else is represented as objects. NOTE on Java 1.5 improvement: Primitive types are usually automatically converted to corresponding object types. Before Java 1.5, you had to convert between primitive types and Object types explicitly. CMPT 125: Data and Expressions, Lecture 3 13

14 Numeric Primitive Data Types Java has two basic types of numeric values: 1. integers (4 types) 2. floating points (with a fractional part) (2 types) Type # bits Min Value Max Value integer: byte short 16-32,768 32,767 int 32-2,147,483,648 2,147,483,647 long 64-9,223,372,036,854,775,808 9,223,372,036,854,775,807 floating point: float E+38 (7 s.f.) 3.4E+38 (7 s.f.) double E+308 (15 s.f.) 1.7E+308 (15 s.f.) Table 1: Numeric Primitive Data Types All numeric types are signed, i.e., they may store both positive and negative values. Generally, for floating point values, always use double to avoid problems related to round-off errors. CMPT 125: Data and Expressions, Lecture 3 14

15 Numeric Literals A numeric literal is composed of a series of digits followed by an optional suffix to indicate its type. The number 34 may be represented as follows: literal type 34 int (default) 34L (or 34l) long 34F (or 34f) float 34D (or 34d) double 34.0 double (default) Table 2: Numeric Literals. An integer literal defaults to type int and a floating point literal defaults to type double. CMPT 125: Data and Expressions, Lecture 3 15

16 Characters A character literal represents a single character and is expressed using single quotes: a, A, 7, %. Recall, string are expressed using double-quotes ( ). char yes_c = Y ; \\ char String yes_s = yes ; \\ string CMPT 125: Data and Expressions, Lecture 3 16

17 Character Set A character set is a list of characters in a particular order. A particular value is assigned to each character according to its position in the set. The ASCII (American Standard Code for Information Interchange) consists of 128 different characters values, each using 7 bits: 1. non-printing (or control) characters (NULL, ESC, TAB etc) 2. special symbols: &,, etc. 3. digits: punctuation:., ;,,, etc. 5. lowercase alphabetic characters a through z 6. uppercase alphabetic characters A through Z CMPT 125: Data and Expressions, Lecture 3 17

18 Unicode Character Set ASCII was extended from 7 to 8 bits doubling the number of possible characters. Still, this is not enough to support the world s alphabets. The Unicode character set, chosen by Java, uses 16 bits per character, supporting 65,536 unique characters. ASCII is a subset of Unicode. CMPT 125: Data and Expressions, Lecture 3 18

19 Booleans A boolean literal represents a logical value. The words true, false are reserved in Java. A boolean is defined in Java using the reserved word boolean. boolean opened = false; A boolean cannot be converted to any other type, nor can any other value be converted to a boolean. CMPT 125: Data and Expressions, Lecture 3 19

20 Expressions Expressions are combinations of operators and operands used to perform a calculation. Operands may be literals, constants, variables, or other sources of data. Operation Operator addition + subtraction - multiplication * division - modulus (remainder) % Table 3: Arithmetic Operations, defined for both integer and floating point. If either or both of the numeric operands are floating point values, the result will also be floating point. If both of the numeric operands are integers, the result will also be an integer. CMPT 125: Data and Expressions, Lecture 3 20

21 Integer Division CAUTION when using the division operator / : If both operands are integers, integer division will be performed, and the result will be an integer with any fractional part being discarded. public static void main(string arg[]) { System.out.println( Integer division: + 10/4); System.out.println( Floating point division: /4); System.out.println( Floating point division: + 10/4.0); System.out.println( Floating point division: /4.0); } OUTPUT: Integer division: 2 Floating point division: 2.5 Floating point division: 2.5 Floating point division: 2.5 CMPT 125: Data and Expressions, Lecture 3 21

22 Unary and Binary Operators A unary operator has only one operand, while a binary operator has two. The + and - can be either unary, representing positive and negative numbers) or binary, accomplishing addition and subtraction. CMPT 125: Data and Expressions, Lecture 3 22

23 Operator Precedence What is the result of the following expression? result = / 2; Operator precedence in Java generally follow the rules of algebra: multiplication, division and the modulo operator have equal precedence. addition and subtraction have equal precedence, which is lower than those listed above. operators with the same level of precedence are performed left to right. CMPT 125: Data and Expressions, Lecture 3 23

24 Forcing precedence using parentheses Precedence can be forced using parentheses. result = (14 + 8) / 2; //result = 11 If parentheses are nested, innermost expressions are evaluated first. result = 3 * ((18-4) / 2); //result = 21 Ensure that the number of left parentheses match the number of right parentheses. CMPT 125: Data and Expressions, Lecture 3 24

25 Precedence Among Java Operators Since the computed result is stored in the variable to the LHS of the assignment operator (=), the assignment operator has a lowest precedence of all. Precedence Operator Operation Associates Level 1 + unary plus R to L unary minus 2 multiplication L to R / division % remainder 3 + addition L to R subtraction + string concatenation 4 = assignment R to L CMPT 125: Data and Expressions, Lecture 3 25

26 Increment and decrement operators Two other useful arithmetic operators (for either integer or floating point): 1. increment operator (++): adds 1 to any value 2. decrement operator (--): subtracts 1 from any value The following two statements are equivalent: count++; cound = count + 1; The increment or decrement operators can be applied after or before a variable (postfix form or prefix form respectively) yielding different results: count = 15; total = count++; //The value of count is assigned and then //incremented, yielding: total = 15 or count = 15; total = ++count; //The value is incremented and then //assigned, yielding: total = 16 CMPT 125: Data and Expressions, Lecture 3 26

27 Assignment Operators Some assignment and arithmetic operations are very common and may be combined for convenience: total += 5; total += (sum - 12) / count; product *= num1 + num2; product %= (highest - 40) / 2; is equivalent to: total = total + 5; total = total + (sum - 12) / count; product = product * (num1 + num2); product = product % ((highest - 40) / 2); CMPT 125: Data and Expressions, Lecture 3 27

28 Data Conversion There are two types of conversion from one primitive type to another: 1. widening conversions: converting from one data type to one requiring the same or more memory space. There is no loss of information except from integer to floating point (where least significant digits may be lost). 2. narrowing conversions: converting from one data type to one that is smaller. Information is more likely to be lost (magnitude and precision). Narrowing is harrowing and should be avoided! A short (16 bits) to a char (16 bits) is considered narrowing because the sign bit is incorporated into the new character value. Since the character is unsigned, a negative integer will not be converted correctly. CMPT 125: Data and Expressions, Lecture 3 28

29 Techniques for Data Conversion 1. assignment conversion: assigning a value of one type to a variable of a new, compatible, type. int dollars = 6; double money; money = dollars; converts the value of dollars from int to double. 2. promotion: when an operand needs be promoted in order to accomplish an operation. dividing a floating point by an integer: int count = 2; float mass = ; mass = mass / count; passing an integer to an operator or method that expects a floating point concatenation of a number with a string (the number is promoted to a string). 3. casting: a Java operator specified by a type name in parentheses. double total = (double) count; CMPT 125: Data and Expressions, Lecture 3 29

30 Creating Objects Consider the two declarations: int num; String name; The first declaration creates a variable that holds an integer value and the second creates a variable that holds a reference to a String object. Neither of the two are are initializaed, and therefore are undefined, that is, they don t contain any data. num name Figure 4: A declaration creating empty variable holders. We may also create a reference that doesn t point to an object by using the null operator, a reserved word in Java. String name = null; CMPT 125: Data and Expressions, Lecture 3 30

31 Instantiation the new operator The new operator creates an instance of the class, and returns a reference to the newly created object. The new operator is followed by a call to the class constructor, a method with the same name as the class, allowing object initialization. Following these assignemnt statements num = 12; name = new String("Kurt Vonnegut"); the variables may be viewed as: num 20 name "Kurt Vonnegut" Figure 5: Instantiation. CMPT 125: Data and Expressions, Lecture 3 31

32 Shortcut notation Declaring an object reference and creating the object can be done in a single declaration statement: String name = new String("Kurt Vonnegut"); Because this kind of initialization is rather common, it can be done by shortcut notation to produce exactly the equivalent result: String name = "Kurt Vonnegut"; Once an object is instantiated, the dot operator may be used to access its methods or variables. len = name.length(); CMPT 125: Data and Expressions, Lecture 3 32

33 Aliases Multiple reference variables can refer to the same object. Consider two references str1 and str2 initially pointing to different objects. String str1 = string1 ; String str2 = string2 ; str1 = str2; The last assignemnt statement means there is now no longer any way of retrieving the object pointed to by ref1 creating a potential memory leak. Luckily Java has automatic garbage colloection, and can free this object from memory. If there are two references to an object, and one reference changes the object, this will also impact the other referenece. str2 = newstring ; Recall that str1 = str2, and this statement will change the contents of both! CMPT 125: Data and Expressions, Lecture 3 33

CSCI 2010 Principles of Computer Science. Data and Expressions 08/09/2013 CSCI

CSCI 2010 Principles of Computer Science. Data and Expressions 08/09/2013 CSCI CSCI 2010 Principles of Computer Science Data and Expressions 08/09/2013 CSCI 2010 1 Data Types, Variables and Expressions in Java We look at the primitive data types, strings and expressions that are

More information

Data and Expressions. Outline. Data and Expressions 12/18/2010. Let's explore some other fundamental programming concepts. Chapter 2 focuses on:

Data and Expressions. Outline. Data and Expressions 12/18/2010. Let's explore some other fundamental programming concepts. Chapter 2 focuses on: Data and Expressions Data and Expressions Let's explore some other fundamental programming concepts Chapter 2 focuses on: Character Strings Primitive Data The Declaration And Use Of Variables Expressions

More information

ECE 122 Engineering Problem Solving with Java

ECE 122 Engineering Problem Solving with Java ECE 122 Engineering Problem Solving with Java Lecture 3 Expression Evaluation and Program Interaction Outline Problem: How do I input data and use it in complicated expressions Creating complicated expressions

More information

A variable is a name for a location in memory A variable must be declared

A variable is a name for a location in memory A variable must be declared Variables A variable is a name for a location in memory A variable must be declared, specifying the variable's name and the type of information that will be held in it data type variable name int total;

More information

CONTENTS: Compilation Data and Expressions COMP 202. More on Chapter 2

CONTENTS: Compilation Data and Expressions COMP 202. More on Chapter 2 CONTENTS: Compilation Data and Expressions COMP 202 More on Chapter 2 Programming Language Levels There are many programming language levels: machine language assembly language high-level language Java,

More information

Chapter 2: Data and Expressions

Chapter 2: Data and Expressions Chapter 2: Data and Expressions CS 121 Department of Computer Science College of Engineering Boise State University January 15, 2015 Chapter 2: Data and Expressions CS 121 1 / 1 Chapter 2 Part 1: Data

More information

Chapter. Let's explore some other fundamental programming concepts

Chapter. Let's explore some other fundamental programming concepts Data and Expressions 2 Chapter 5 TH EDITION Lewis & Loftus java Software Solutions Foundations of Program Design 2007 Pearson Addison-Wesley. All rights reserved Data and Expressions Let's explore some

More information

Chapter 2: Data and Expressions

Chapter 2: Data and Expressions Chapter 2: Data and Expressions CS 121 Department of Computer Science College of Engineering Boise State University August 21, 2017 Chapter 2: Data and Expressions CS 121 1 / 51 Chapter 1 Terminology Review

More information

Chapter 2: Data and Expressions

Chapter 2: Data and Expressions Chapter 2: Data and Expressions CS 121 Department of Computer Science College of Engineering Boise State University April 21, 2015 Chapter 2: Data and Expressions CS 121 1 / 53 Chapter 2 Part 1: Data Types

More information

Introduction to Java Chapters 1 and 2 The Java Language Section 1.1 Data & Expressions Sections

Introduction to Java Chapters 1 and 2 The Java Language Section 1.1 Data & Expressions Sections Introduction to Java Chapters 1 and 2 The Java Language Section 1.1 Data & Expressions Sections 2.1 2.5 Instructor: Scott Kristjanson CMPT 125/125 SFU Burnaby, Fall 2013 2 Scope Introduce the Java programming

More information

Basics of Java Programming

Basics of Java Programming Basics of Java Programming Lecture 2 COP 3252 Summer 2017 May 16, 2017 Components of a Java Program statements - A statement is some action or sequence of actions, given as a command in code. A statement

More information

Expressions and Data Types CSC 121 Spring 2015 Howard Rosenthal

Expressions and Data Types CSC 121 Spring 2015 Howard Rosenthal Expressions and Data Types CSC 121 Spring 2015 Howard Rosenthal Lesson Goals Understand the basic constructs of a Java Program Understand how to use basic identifiers Understand simple Java data types

More information

Full file at

Full file at Java Programming: From Problem Analysis to Program Design, 3 rd Edition 2-1 Chapter 2 Basic Elements of Java At a Glance Instructor s Manual Table of Contents Overview Objectives s Quick Quizzes Class

More information

Module 2 - Part 2 DATA TYPES AND EXPRESSIONS 1/15/19 CSE 1321 MODULE 2 1

Module 2 - Part 2 DATA TYPES AND EXPRESSIONS 1/15/19 CSE 1321 MODULE 2 1 Module 2 - Part 2 DATA TYPES AND EXPRESSIONS 1/15/19 CSE 1321 MODULE 2 1 Topics 1. Expressions 2. Operator precedence 3. Shorthand operators 4. Data/Type Conversion 1/15/19 CSE 1321 MODULE 2 2 Expressions

More information

Program Fundamentals

Program Fundamentals Program Fundamentals /* HelloWorld.java * The classic Hello, world! program */ class HelloWorld { public static void main (String[ ] args) { System.out.println( Hello, world! ); } } /* HelloWorld.java

More information

Declaration and Memory

Declaration and Memory Declaration and Memory With the declaration int width; the compiler will set aside a 4-byte (32-bit) block of memory (see right) The compiler has a symbol table, which will have an entry such as Identifier

More information

Review Chapters 1 to 4. Instructor: Scott Kristjanson CMPT 125/125 SFU Burnaby, Fall 2013

Review Chapters 1 to 4. Instructor: Scott Kristjanson CMPT 125/125 SFU Burnaby, Fall 2013 Review Chapters 1 to 4 Instructor: Scott Kristjanson CMPT 125/125 SFU Burnaby, Fall 2013 Introduction to Java Chapters 1 and 2 The Java Language Section 1.1 Data & Expressions Sections 2.1 2.5 Instructor:

More information

Java Foundations: Introduction to Program Design & Data Structures, 4e John Lewis, Peter DePasquale, Joseph Chase Test Bank: Chapter 2

Java Foundations: Introduction to Program Design & Data Structures, 4e John Lewis, Peter DePasquale, Joseph Chase Test Bank: Chapter 2 Java Foundations Introduction to Program Design and Data Structures 4th Edition Lewis TEST BANK Full download at : https://testbankreal.com/download/java-foundations-introduction-toprogram-design-and-data-structures-4th-edition-lewis-test-bank/

More information

Expressions and Data Types CSC 121 Fall 2015 Howard Rosenthal

Expressions and Data Types CSC 121 Fall 2015 Howard Rosenthal Expressions and Data Types CSC 121 Fall 2015 Howard Rosenthal Lesson Goals Understand the basic constructs of a Java Program Understand how to use basic identifiers Understand simple Java data types and

More information

COMP Primitive and Class Types. Yi Hong May 14, 2015

COMP Primitive and Class Types. Yi Hong May 14, 2015 COMP 110-001 Primitive and Class Types Yi Hong May 14, 2015 Review What are the two major parts of an object? What is the relationship between class and object? Design a simple class for Student How to

More information

Primitive Data Types: Intro

Primitive Data Types: Intro Primitive Data Types: Intro Primitive data types represent single values and are built into a language Java primitive numeric data types: 1. Integral types (a) byte (b) int (c) short (d) long 2. Real types

More information

Chapter 2 Using Data. Instructor s Manual Table of Contents. At a Glance. Overview. Objectives. Teaching Tips. Quick Quizzes. Class Discussion Topics

Chapter 2 Using Data. Instructor s Manual Table of Contents. At a Glance. Overview. Objectives. Teaching Tips. Quick Quizzes. Class Discussion Topics Java Programming, Sixth Edition 2-1 Chapter 2 Using Data At a Glance Instructor s Manual Table of Contents Overview Objectives Teaching Tips Quick Quizzes Class Discussion Topics Additional Projects Additional

More information

Data Conversion & Scanner Class

Data Conversion & Scanner Class Data Conversion & Scanner Class Quick review of last lecture August 29, 2007 ComS 207: Programming I (in Java) Iowa State University, FALL 2007 Instructor: Alexander Stoytchev Numeric Primitive Data Storing

More information

Chapter 2 Elementary Programming

Chapter 2 Elementary Programming Chapter 2 Elementary Programming Part I 1 Motivations In the preceding chapter, you learned how to create, compile, and run a Java program. Starting from this chapter, you will learn how to solve practical

More information

CS5000: Foundations of Programming. Mingon Kang, PhD Computer Science, Kennesaw State University

CS5000: Foundations of Programming. Mingon Kang, PhD Computer Science, Kennesaw State University CS5000: Foundations of Programming Mingon Kang, PhD Computer Science, Kennesaw State University Overview of Source Code Components Comments Library declaration Classes Functions Variables Comments Can

More information

Data and Variables. Data Types Expressions. String Concatenation Variables Declaration Assignment Shorthand operators. Operators Precedence

Data and Variables. Data Types Expressions. String Concatenation Variables Declaration Assignment Shorthand operators. Operators Precedence Data and Variables Data Types Expressions Operators Precedence String Concatenation Variables Declaration Assignment Shorthand operators Review class All code in a java file is written in a class public

More information

Full file at

Full file at Java Programming, Fifth Edition 2-1 Chapter 2 Using Data within a Program At a Glance Instructor s Manual Table of Contents Overview Objectives Teaching Tips Quick Quizzes Class Discussion Topics Additional

More information

Getting started with Java

Getting started with Java Getting started with Java Magic Lines public class MagicLines { public static void main(string[] args) { } } Comments Comments are lines in your code that get ignored during execution. Good for leaving

More information

Visual C# Instructor s Manual Table of Contents

Visual C# Instructor s Manual Table of Contents Visual C# 2005 2-1 Chapter 2 Using Data At a Glance Instructor s Manual Table of Contents Overview Objectives s Quick Quizzes Class Discussion Topics Additional Projects Additional Resources Key Terms

More information

Lecture Notes. System.out.println( Circle radius: + radius + area: + area); radius radius area area value

Lecture Notes. System.out.println( Circle radius: + radius + area: + area); radius radius area area value Lecture Notes 1. Comments a. /* */ b. // 2. Program Structures a. public class ComputeArea { public static void main(string[ ] args) { // input radius // compute area algorithm // output area Actions to

More information

3. Java - Language Constructs I

3. Java - Language Constructs I Educational Objectives 3. Java - Language Constructs I Names and Identifiers, Variables, Assignments, Constants, Datatypes, Operations, Evaluation of Expressions, Type Conversions You know the basic blocks

More information

Program Elements -- Introduction

Program Elements -- Introduction Program Elements -- Introduction We can now examine the core elements of programming Chapter 3 focuses on: data types variable declaration and use operators and expressions decisions and loops input and

More information

Expressions and Data Types CSC 121 Spring 2017 Howard Rosenthal

Expressions and Data Types CSC 121 Spring 2017 Howard Rosenthal Expressions and Data Types CSC 121 Spring 2017 Howard Rosenthal Lesson Goals Understand the basic constructs of a Java Program Understand how to use basic identifiers Understand simple Java data types

More information

Objects and Types. COMS W1007 Introduction to Computer Science. Christopher Conway 29 May 2003

Objects and Types. COMS W1007 Introduction to Computer Science. Christopher Conway 29 May 2003 Objects and Types COMS W1007 Introduction to Computer Science Christopher Conway 29 May 2003 Java Programs A Java program contains at least one class definition. public class Hello { public static void

More information

A Java program contains at least one class definition.

A Java program contains at least one class definition. Java Programs Identifiers Objects and Types COMS W1007 Introduction to Computer Science Christopher Conway 29 May 2003 A Java program contains at least one class definition. public class Hello { public

More information

2: Basics of Java Programming

2: Basics of Java Programming 2: Basics of Java Programming CSC 1051 Algorithms and Data Structures I Dr. Mary-Angela Papalaskari Department of Computing Sciences Villanova University Course website: www.csc.villanova.edu/~map/1051/

More information

AYBUKE BUYUKCAYLI KORAY OZUYAR MUSTAFA SOYLU. Week 21/02/ /02/2007 Lecture Notes: ASCII

AYBUKE BUYUKCAYLI KORAY OZUYAR MUSTAFA SOYLU. Week 21/02/ /02/2007 Lecture Notes: ASCII AYBUKE BUYUKCAYLI KORAY OZUYAR MUSTAFA SOYLU Week 21/02/2007-23/02/2007 Lecture Notes: ASCII 7 bits = 128 characters 8 bits = 256characters Unicode = 16 bits Char Boolean boolean frag; flag = true; flag

More information

Operators and Expressions

Operators and Expressions Operators and Expressions Conversions. Widening and Narrowing Primitive Conversions Widening and Narrowing Reference Conversions Conversions up the type hierarchy are called widening reference conversions

More information

More Programming Constructs -- Introduction

More Programming Constructs -- Introduction More Programming Constructs -- Introduction We can now examine some additional programming concepts and constructs Chapter 5 focuses on: internal data representation conversions between one data type and

More information

COMP-202 Unit 2: Java Basics. CONTENTS: Using Expressions and Variables Types Strings Methods

COMP-202 Unit 2: Java Basics. CONTENTS: Using Expressions and Variables Types Strings Methods COMP-202 Unit 2: Java Basics CONTENTS: Using Expressions and Variables Types Strings Methods Assignment 1 Assignment 1 posted on WebCt and course website. It is due May 18th st at 23:30 Worth 6% Part programming,

More information

Chapter 2 Primitive Data Types and Operations. Objectives

Chapter 2 Primitive Data Types and Operations. Objectives Chapter 2 Primitive Data Types and Operations Prerequisites for Part I Basic computer skills such as using Windows, Internet Explorer, and Microsoft Word Chapter 1 Introduction to Computers, Programs,

More information

JAVA Programming Fundamentals

JAVA Programming Fundamentals Chapter 4 JAVA Programming Fundamentals By: Deepak Bhinde PGT Comp.Sc. JAVA character set Character set is a set of valid characters that a language can recognize. It may be any letter, digit or any symbol

More information

CSc 10200! Introduction to Computing. Lecture 2-3 Edgardo Molina Fall 2013 City College of New York

CSc 10200! Introduction to Computing. Lecture 2-3 Edgardo Molina Fall 2013 City College of New York CSc 10200! Introduction to Computing Lecture 2-3 Edgardo Molina Fall 2013 City College of New York 1 C++ for Engineers and Scientists Third Edition Chapter 2 Problem Solving Using C++ 2 Objectives In this

More information

JAVA OPERATORS GENERAL

JAVA OPERATORS GENERAL JAVA OPERATORS GENERAL Java provides a rich set of operators to manipulate variables. We can divide all the Java operators into the following groups: Arithmetic Operators Relational Operators Bitwise Operators

More information

LESSON 1. A C program is constructed as a sequence of characters. Among the characters that can be used in a program are:

LESSON 1. A C program is constructed as a sequence of characters. Among the characters that can be used in a program are: LESSON 1 FUNDAMENTALS OF C The purpose of this lesson is to explain the fundamental elements of the C programming language. C like other languages has all alphabet and rules for putting together words

More information

Java enum, casts, and others (Select portions of Chapters 4 & 5)

Java enum, casts, and others (Select portions of Chapters 4 & 5) Enum or enumerates types Java enum, casts, and others (Select portions of Chapters 4 & 5) Sharma Chakravarthy Information Technology Laboratory (IT Lab) Computer Science and Engineering Department The

More information

Zheng-Liang Lu Java Programming 45 / 79

Zheng-Liang Lu Java Programming 45 / 79 1 class Lecture2 { 2 3 "Elementray Programming" 4 5 } 6 7 / References 8 [1] Ch. 2 in YDL 9 [2] Ch. 2 and 3 in Sharan 10 [3] Ch. 2 in HS 11 / Zheng-Liang Lu Java Programming 45 / 79 Example Given a radius

More information

12/22/11. Java How to Program, 9/e. Help you get started with Eclipse and NetBeans integrated development environments.

12/22/11. Java How to Program, 9/e. Help you get started with Eclipse and NetBeans integrated development environments. Java How to Program, 9/e Education, Inc. All Rights Reserved. } Java application programming } Use tools from the JDK to compile and run programs. } Videos at www.deitel.com/books/jhtp9/ Help you get started

More information

4 Programming Fundamentals. Introduction to Programming 1 1

4 Programming Fundamentals. Introduction to Programming 1 1 4 Programming Fundamentals Introduction to Programming 1 1 Objectives At the end of the lesson, the student should be able to: Identify the basic parts of a Java program Differentiate among Java literals,

More information

Basic Computation. Chapter 2

Basic Computation. Chapter 2 Basic Computation Chapter 2 Outline Variables and Expressions The Class String Keyboard and Screen I/O Documentation and Style Variables Variables store data such as numbers and letters. Think of them

More information

CMPT 125: Lecture 4 Conditionals and Loops

CMPT 125: Lecture 4 Conditionals and Loops CMPT 125: Lecture 4 Conditionals and Loops Tamara Smyth, tamaras@cs.sfu.ca School of Computing Science, Simon Fraser University January 17, 2009 1 Flow of Control The order in which statements are executed

More information

COMP 110 Introduction to Programming. What did we discuss?

COMP 110 Introduction to Programming. What did we discuss? COMP 110 Introduction to Programming Fall 2015 Time: TR 9:30 10:45 Room: AR 121 (Hanes Art Center) Jay Aikat FB 314, aikat@cs.unc.edu Previous Class What did we discuss? COMP 110 Fall 2015 2 1 Today Announcements

More information

Chapter 6 Primitive types

Chapter 6 Primitive types Chapter 6 Primitive types Lesson page 6-1. Primitive types Question 1. There are an infinite number of integers, so it would be too ineffient to have a type integer that would contain all of them. Question

More information

Lesson 02 Data Types and Statements. MIT 12043, Fundamentals of Programming By: S. Sabraz Nawaz Senior Lecturer in MIT Department of MIT FMC, SEUSL

Lesson 02 Data Types and Statements. MIT 12043, Fundamentals of Programming By: S. Sabraz Nawaz Senior Lecturer in MIT Department of MIT FMC, SEUSL Lesson 02 Data Types and Statements MIT 12043, Fundamentals of Programming By: S. Sabraz Nawaz Senior Lecturer in MIT Department of MIT FMC, SEUSL Topics Covered Statements Variables Constants Data Types

More information

Information Science 1

Information Science 1 Information Science 1 Simple Calcula,ons Week 09 College of Information Science and Engineering Ritsumeikan University Topics covered l Terms and concepts from Week 8 l Simple calculations Documenting

More information

Programming with Java

Programming with Java Programming with Java Data Types & Input Statement Lecture 04 First stage Software Engineering Dep. Saman M. Omer 2017-2018 Objectives q By the end of this lecture you should be able to : ü Know rules

More information

CS313D: ADVANCED PROGRAMMING LANGUAGE

CS313D: ADVANCED PROGRAMMING LANGUAGE CS313D: ADVANCED PROGRAMMING LANGUAGE Computer Science department Lecture 2 : C# Language Basics Lecture Contents 2 The C# language First program Variables and constants Input/output Expressions and casting

More information

Learning objectives: Objects and Primitive Data. Introduction to Objects. A Predefined Object. The print versus the println Methods

Learning objectives: Objects and Primitive Data. Introduction to Objects. A Predefined Object. The print versus the println Methods CSI1102 Introduction to Software Design Chapter 2: Objects and Primitive Data Learning objectives: Objects and Primitive Data Introducing objects and their properties Predefined objects: System.out Variables

More information

Chapter 1 Introduction to java

Chapter 1 Introduction to java Chapter 1 Introduction to java History of java Java was created by by Sun Microsystems team led by James Gosling (1991) It was mainly used for home appliance, it later became a general purpose programming

More information

Professor: Sana Odeh Lecture 3 Python 3.1 Variables, Primitive Data Types & arithmetic operators

Professor: Sana Odeh Lecture 3 Python 3.1 Variables, Primitive Data Types & arithmetic operators 1 Professor: Sana Odeh odeh@courant.nyu.edu Lecture 3 Python 3.1 Variables, Primitive Data Types & arithmetic operators Review What s wrong with this line of code? print( He said Hello ) What s wrong with

More information

Lecture 3. More About C

Lecture 3. More About C Copyright 1996 David R. Hanson Computer Science 126, Fall 1996 3-1 Lecture 3. More About C Programming languages have their lingo Programming language Types are categories of values int, float, char Constants

More information

Chapter 3: Operators, Expressions and Type Conversion

Chapter 3: Operators, Expressions and Type Conversion 101 Chapter 3 Operators, Expressions and Type Conversion Chapter 3: Operators, Expressions and Type Conversion Objectives To use basic arithmetic operators. To use increment and decrement operators. To

More information

Lesson 02 Data Types and Statements. MIT 11053, Fundamentals of Programming By: S. Sabraz Nawaz Senior Lecturer in MIT Department of MIT FMC, SEUSL

Lesson 02 Data Types and Statements. MIT 11053, Fundamentals of Programming By: S. Sabraz Nawaz Senior Lecturer in MIT Department of MIT FMC, SEUSL Lesson 02 Data Types and Statements MIT 11053, Fundamentals of Programming By: S. Sabraz Nawaz Senior Lecturer in MIT Department of MIT FMC, SEUSL Topics Covered Statements Variables Data Types Arithmetic

More information

Chapter 2: Using Data

Chapter 2: Using Data Chapter 2: Using Data TRUE/FALSE 1. A variable can hold more than one value at a time. F PTS: 1 REF: 52 2. The legal integer values are -2 31 through 2 31-1. These are the highest and lowest values that

More information

Work relative to other classes

Work relative to other classes Work relative to other classes 1 Hours/week on projects 2 C BOOTCAMP DAY 1 CS3600, Northeastern University Slides adapted from Anandha Gopalan s CS132 course at Univ. of Pittsburgh Overview C: A language

More information

Operators. Java operators are classified into three categories:

Operators. Java operators are classified into three categories: Operators Operators are symbols that perform arithmetic and logical operations on operands and provide a meaningful result. Operands are data values (variables or constants) which are involved in operations.

More information

Object oriented programming. Instructor: Masoud Asghari Web page: Ch: 3

Object oriented programming. Instructor: Masoud Asghari Web page:   Ch: 3 Object oriented programming Instructor: Masoud Asghari Web page: http://www.masses.ir/lectures/oops2017sut Ch: 3 1 In this slide We follow: https://docs.oracle.com/javase/tutorial/index.html Trail: Learning

More information

Lecture 3: Variables and assignment

Lecture 3: Variables and assignment Lecture 3: Variables and assignment CSC 1051 Data Structures and Algorithms I Dr. Mary-Angela Papalaskari Department of Computing Sciences Villanova University Course website: www.csc.villanova.edu/~map/1051/

More information

Chapter 2 ELEMENTARY PROGRAMMING

Chapter 2 ELEMENTARY PROGRAMMING Chapter 2 ELEMENTARY PROGRAMMING Lecture notes for computer programming 1 Faculty of Engineering and Information Technology Prepared by: Iyad Albayouk ١ Objectives To write Java programs to perform simple

More information

Operators. Lecture 3 COP 3014 Spring January 16, 2018

Operators. Lecture 3 COP 3014 Spring January 16, 2018 Operators Lecture 3 COP 3014 Spring 2018 January 16, 2018 Operators Special built-in symbols that have functionality, and work on operands operand an input to an operator Arity - how many operands an operator

More information

Assoc. Prof. Dr. Marenglen Biba. (C) 2010 Pearson Education, Inc. All rights reserved.

Assoc. Prof. Dr. Marenglen Biba. (C) 2010 Pearson Education, Inc. All rights reserved. Assoc. Prof. Dr. Marenglen Biba (C) 2010 Pearson Education, Inc. All rights reserved. Java application A computer program that executes when you use the java command to launch the Java Virtual Machine

More information

Information Science 1

Information Science 1 Topics covered Information Science 1 Terms and concepts from Week 8 Simple calculations Documenting programs Simple Calcula,ons Expressions Arithmetic operators and arithmetic operator precedence Mixed-type

More information

Introduction To Java. Chapter 1. Origins of the Java Language. Origins of the Java Language. Objects and Methods. Origins of the Java Language

Introduction To Java. Chapter 1. Origins of the Java Language. Origins of the Java Language. Objects and Methods. Origins of the Java Language Chapter 1 Getting Started Introduction To Java Most people are familiar with Java as a language for Internet applications We will study Java as a general purpose programming language The syntax of expressions

More information

LECTURE 3 C++ Basics Part 2

LECTURE 3 C++ Basics Part 2 LECTURE 3 C++ Basics Part 2 OVERVIEW Operators Type Conversions OPERATORS Operators are special built-in symbols that have functionality, and work on operands. Operators are actually functions that use

More information

Prof. Navrati Saxena TA: Rochak Sachan

Prof. Navrati Saxena TA: Rochak Sachan JAVA Prof. Navrati Saxena TA: Rochak Sachan Operators Operator Arithmetic Relational Logical Bitwise 1. Arithmetic Operators are used in mathematical expressions. S.N. 0 Operator Result 1. + Addition 6.

More information

CHAPTER 3 Expressions, Functions, Output

CHAPTER 3 Expressions, Functions, Output CHAPTER 3 Expressions, Functions, Output More Data Types: Integral Number Types short, long, int (all represent integer values with no fractional part). Computer Representation of integer numbers - Number

More information

Chapter 2 Working with Data Types and Operators

Chapter 2 Working with Data Types and Operators JavaScript, Fourth Edition 2-1 Chapter 2 Working with Data Types and Operators At a Glance Instructor s Manual Table of Contents Overview Objectives Teaching Tips Quick Quizzes Class Discussion Topics

More information

CSC 1214: Object-Oriented Programming

CSC 1214: Object-Oriented Programming CSC 1214: Object-Oriented Programming J. Kizito Makerere University e-mail: jkizito@cis.mak.ac.ug www: http://serval.ug/~jona materials: http://serval.ug/~jona/materials/csc1214 e-learning environment:

More information

Chapter 2 Primitive Data Types and Operations

Chapter 2 Primitive Data Types and Operations Chapter 2 Primitive Data Types and Operations 2.1 Introduction You will be introduced to Java primitive data types and related subjects, such as variables constants, data types, operators, and expressions.

More information

1.00 Lecture 4. Promotion

1.00 Lecture 4. Promotion 1.00 Lecture 4 Data Types, Operators Reading for next time: Big Java: sections 6.1-6.4 Promotion increasing capacity Data Type Allowed Promotions double None float double long float,double int long,float,double

More information

Types and Expressions. Chapter 3

Types and Expressions. Chapter 3 Types and Expressions Chapter 3 Chapter Contents 3.1 Introductory Example: Einstein's Equation 3.2 Primitive Types and Reference Types 3.3 Numeric Types and Expressions 3.4 Assignment Expressions 3.5 Java's

More information

CSE 1001 Fundamentals of Software Development 1. Identifiers, Variables, and Data Types Dr. H. Crawford Fall 2018

CSE 1001 Fundamentals of Software Development 1. Identifiers, Variables, and Data Types Dr. H. Crawford Fall 2018 CSE 1001 Fundamentals of Software Development 1 Identifiers, Variables, and Data Types Dr. H. Crawford Fall 2018 Identifiers, Variables and Data Types Reserved Words Identifiers in C Variables and Values

More information

A complex expression to evaluate we need to reduce it to a series of simple expressions. E.g * 7 =>2+ 35 => 37. E.g.

A complex expression to evaluate we need to reduce it to a series of simple expressions. E.g * 7 =>2+ 35 => 37. E.g. 1.3a Expressions Expressions An Expression is a sequence of operands and operators that reduces to a single value. An operator is a syntactical token that requires an action be taken An operand is an object

More information

Chapter 2: Using Data

Chapter 2: Using Data Chapter 2: Using Data TRUE/FALSE 1. A variable can hold more than one value at a time. F PTS: 1 REF: 52 2. The legal integer values are -2 31 through 2 31-1. These are the highest and lowest values that

More information

Basic Operations jgrasp debugger Writing Programs & Checkstyle

Basic Operations jgrasp debugger Writing Programs & Checkstyle Basic Operations jgrasp debugger Writing Programs & Checkstyle Suppose you wanted to write a computer game to play "Rock, Paper, Scissors". How many combinations are there? Is there a tricky way to represent

More information

Java Notes. 10th ICSE. Saravanan Ganesh

Java Notes. 10th ICSE. Saravanan Ganesh Java Notes 10th ICSE Saravanan Ganesh 13 Java Character Set Character set is a set of valid characters that a language can recognise A character represents any letter, digit or any other sign Java uses

More information

Le L c e t c ur u e e 2 To T p o i p c i s c t o o b e b e co c v o e v r e ed e Variables Operators

Le L c e t c ur u e e 2 To T p o i p c i s c t o o b e b e co c v o e v r e ed e Variables Operators Course Name: Advanced Java Lecture 2 Topics to be covered Variables Operators Variables -Introduction A variables can be considered as a name given to the location in memory where values are stored. One

More information

COSC 236 Section 101 Computer Science 1 -- Prof. Michael A. Soderstrand

COSC 236 Section 101 Computer Science 1 -- Prof. Michael A. Soderstrand COSC 236 Section 101 Computer Science 1 -- Prof. Michael A. Soderstrand COSC 236 Web Site I have decided to keep this site for the whole semester I still hope to have blackboard up and running, but you

More information

Chapter 2: Using Data

Chapter 2: Using Data Chapter 2: Using Data Declaring Variables Constant Cannot be changed after a program is compiled Variable A named location in computer memory that can hold different values at different points in time

More information

cis20.1 design and implementation of software applications I fall 2007 lecture # I.2 topics: introduction to java, part 1

cis20.1 design and implementation of software applications I fall 2007 lecture # I.2 topics: introduction to java, part 1 topics: introduction to java, part 1 cis20.1 design and implementation of software applications I fall 2007 lecture # I.2 cis20.1-fall2007-sklar-leci.2 1 Java. Java is an object-oriented language: it is

More information

CIS 110: Introduction to Computer Programming

CIS 110: Introduction to Computer Programming CIS 110: Introduction to Computer Programming Lecture 3 Express Yourself ( 2.1) 9/16/2011 CIS 110 (11fa) - University of Pennsylvania 1 Outline 1. Data representation and types 2. Expressions 9/16/2011

More information

COMP6700/2140 Data and Types

COMP6700/2140 Data and Types COMP6700/2140 Data and Types Alexei B Khorev and Josh Milthorpe Research School of Computer Science, ANU February 2017 Alexei B Khorev and Josh Milthorpe (RSCS, ANU) COMP6700/2140 Data and Types February

More information

Building Java Programs

Building Java Programs Building Java Programs Chapter 2 Lecture 2-1: Expressions and Variables reading: 2.1-2.2 1 Data and expressions reading: 2.1 self-check: 1-4 videos: Ch. 2 #1 2 Data types type: A category or set of data

More information

Language Basics. /* The NUMBER GAME - User tries to guess a number between 1 and 10 */ /* Generate a random number between 1 and 10 */

Language Basics. /* The NUMBER GAME - User tries to guess a number between 1 and 10 */ /* Generate a random number between 1 and 10 */ Overview Language Basics This chapter describes the basic elements of Rexx. It discusses the simple components that make up the language. These include script structure, elements of the language, operators,

More information

MODULE 02: BASIC COMPUTATION IN JAVA

MODULE 02: BASIC COMPUTATION IN JAVA MODULE 02: BASIC COMPUTATION IN JAVA Outline Variables Naming Conventions Data Types Primitive Data Types Review: int, double New: boolean, char The String Class Type Conversion Expressions Assignment

More information

Numerical Data. CS 180 Sunil Prabhakar Department of Computer Science Purdue University

Numerical Data. CS 180 Sunil Prabhakar Department of Computer Science Purdue University Numerical Data CS 180 Sunil Prabhakar Department of Computer Science Purdue University Problem Write a program to compute the area and perimeter of a circle given its radius. Requires that we perform operations

More information

Values and Variables 1 / 30

Values and Variables 1 / 30 Values and Variables 1 / 30 Values 2 / 30 Computing Computing is any purposeful activity that marries the representation of some dynamic domain with the representation of some dynamic machine that provides

More information

CS 112 Introduction to Computing II. Wayne Snyder Computer Science Department Boston University

CS 112 Introduction to Computing II. Wayne Snyder Computer Science Department Boston University CS 112 Introduction to Computing II Wayne Snyder Department Boston University Today: Java basics: Compilation vs Interpretation Program structure Statements Values Variables Types Operators and Expressions

More information

A variable is a name that represents a value. For

A variable is a name that represents a value. For DECLARE A VARIABLE A variable is a name that represents a value. For example, you could have the variable myage represent the value 29. Variables can be used to perform many types of calculations. Before

More information

Java provides a rich set of operators to manipulate variables. We can divide all the Java operators into the following groups:

Java provides a rich set of operators to manipulate variables. We can divide all the Java operators into the following groups: Basic Operators Java provides a rich set of operators to manipulate variables. We can divide all the Java operators into the following groups: Arithmetic Operators Relational Operators Bitwise Operators

More information