Se connecter

Se connecter avec OpenID

AP Computer Science A

Welcome to AP Computer Science A
• We use the Java language, but this class is much more rigorous than
Intro to Java
• More programming, but also more theory
• Difficult material…expect to study/practice at home if you want to
• AP Exam: May 2016… college credit  save $$ and time, impressive
on application, be more prepared for college
•  teacher websites  Quinn
– Notes, assignments, and test/quiz dates will be posted here. When you miss
class, it is YOUR responsibility to read the notes and complete the assignments.
Do not…
• Copy code/files
• Google how to do something
• Play games / do anything before all
assignments are done
• Ask “did you grade the tests yet?” or any
variation thereof
• Listen to the band Third Eye Blind
Don’t be “that guy”
• Rules for naming a file
– Begin with a capital letter
– No spaces or punctuation
– Cannot begin with a number
– Each new word starts with a capital letter
Basic output
To display text: System.out.println(“ “);
To go to the next line: put \n between the quotes
System.out.print(“ “);  do not go to next line
Java is case-sensitive
Semi-colons after (almost) every line of code
Demo: HelloWorld
• Variables are memory containers in which info is
• They can hold numbers, letters, words, phrases, etc
• integers are whole numbers (no decimals)
• First, declare the variable – specify the type of info
the variable will hold, and give the variable a name
int x = 0;
• Setting it equal to zero is called initializing the
variable (giving it an initial value)
• Integers are usually initialized to 0, although there
are exceptions to this rule
• Demo
• You give a variable a value by using =, which is
called the assignment operator.
• Important: = does not mean “is equal to!”
• What it really means is “Take what is on the right
side of the equals sign and assign it to what is on
the left side.”
Rules for naming variables
Use meaningful names
Cannot start with a number
Numbers and letters only
Start with a lowercase letter
then capitalize the first letter of other words
Other types of variables
• Double (also known as “floating point number”)
– allows decimals
– much more useful than integers, but takes up more memory
• char
– A single character
– You must put the character in single quotes, if you are giving a
char value in your code
example: char myGrade = ‘ ’;
• String
– Words, phrases, sentences
– Capitalize String
– Use double quotes
example: String firstName= “”;
• Demo
• (MyInfo)
Declare and initialize variables that will hold…
Your age
7 numbers
The average of those 7 numbers
The sum, difference, product, and quotient of the first and last
• your middle initial
• Your favorite book
– Store data in these variables.
– Then display this information. (Example: “The
average is 3.4.”)
Без категории
Taille du fichier
253 Кб