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CSE110 Lecture 04

CSE110 Lecture 04

Principles of Programming with Java
Primitive Data Types
(202005)

B546a9b97d993392e4b22b74b99b91fe?s=128

Javier Gonzalez

May 22, 2017
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  1. CSE110 Principles of Programming with Java Lecture 04: Primitive Data

    Types Javier Gonzalez-Sanchez javiergs@asu.edu javiergs.engineering.asu.edu | javiergs.com Office Hours: By appointment
  2. Javier Gonzalez-Sanchez | CSE110 | Summer 2020 | 2 Summary

    class global variables methods statements instructions local variables
  3. Javier Gonzalez-Sanchez | CSE110 | Summer 2020 | 3 Identifiers

    • Identifiers are the words a programmer uses in a program • An identifier can be made up of letters, digits, the underscore character ( _ ), and the dollar sign • Identifiers cannot begin with a digit 3
  4. Javier Gonzalez-Sanchez | CSE110 | Summer 2020 | 4 Identifiers

    • Java is case sensitive, Total, total, and TOTAL are different identifiers • By convention, Java programmers use different case styles for different types of identifiers, such as: o title case for class names - Lincoln o upper case for constants – MAXIMUM o lower case the first letter for methods and variables 4
  5. Javier Gonzalez-Sanchez | CSE110 | Summer 2020 | 5 White

    Space • Spaces, blank lines, and tabs are called white space • White space is used to separate words and symbols in a program • Extra white space is ignored • Programs should be formatted to enhance readability, using consistent indentation
  6. Javier Gonzalez-Sanchez | CSE110 | Summer 2020 | 6 Spaces,

    Identifiers, and Keywords
  7. Javier Gonzalez-Sanchez | CSE110 | Summer 2020 | 7 Variable

    Declaration (public)(static)type identifier (= value);
  8. Javier Gonzalez-Sanchez | CSE110 | Summer 2020 | 8 Variable

    Declaration • Multiple variables can be created in one declaration int count, temp, result; • A variable can be given an initial value in the declaration int sum = 0; int base = 32, max = 149;
  9. Javier Gonzalez-Sanchez | CSE110 | Summer 2020 | 9 Using

    Variables • An assignment statement changes the value of a variable total = 55;
  10. Javier Gonzalez-Sanchez | CSE110 | Summer 2020 | 10 Example

  11. Javier Gonzalez-Sanchez | CSE110 | Summer 2020 | 11 Variable

    Declaration (public)(static)type identifier (= value);
  12. Javier Gonzalez-Sanchez | CSE110 | Summer 2020 | 12 Data

    Types § There are exactly eight primitive data types in Java § Four of them represent integers: byte, short, int, long § Two of them represent floating point numbers: float, double § One of them represents characters: char § And one of them represents boolean values: boolean
  13. Javier Gonzalez-Sanchez | CSE110 | Summer 2020 | 13 Data

    Types The difference between the various numeric primitive types is their size, and therefore the values they can store: Type Size Min Value Max Value byte 8 bits -128 127 short 16 bits -32,768 32,767 int 32 bits -2^31 2^31 - 1 long 64 bits -2^63 2^63 - 1 float 32 bits +/- 3.4 x 1038 with 7 significant digits double 64 bits +/- 1.7 x 10308 with 15 significant digits
  14. Javier Gonzalez-Sanchez | CSE110 | Summer 2020 | 14 char

    • A char variable stores a single character from the Unicode character set • The Unicode character set uses 16 bits per character, allowing for 65,536 unique characters • It is an international character set, containing symbols and characters from many world languages • Character literals are delimited by single quotes: 'a' 'X' '7' '$' ',' '\n'
  15. Javier Gonzalez-Sanchez | CSE110 | Summer 2020 | 15 Escape

    Sequences Escape Sequence Meaning \b backspace \t tab \n newline \” double quote \’ single quote \\ backslash
  16. Javier Gonzalez-Sanchez | CSE110 | Summer 2020 | 16 boolean

    • A boolean value – only 2 values, true or false • The reserved words true and false are the only valid values for a boolean type boolean done = false; boolean success; success = true;
  17. Javier Gonzalez-Sanchez | CSE110 | Summer 2020 | 17 Global

    Variable
  18. Javier Gonzalez-Sanchez | CSE110 | Summer 2020 | 18 Error

  19. Javier Gonzalez-Sanchez | CSE110 | Summer 2020 | 19 Homework

    Read Chapter 2 Copy, Compile, and Run all source code in this week slides
  20. CSE110 - Principles of Programming Javier Gonzalez-Sanchez javiergs@asu.edu Summer 2020

    Disclaimer. These slides can only be used as study material for the class CSE110 at ASU. They cannot be distributed or used for another purpose.