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AP Computer Science A Textbook

1. Primitive Types

2. Using Objects

3. Boolean Expressions and if Statements

3.1 Boolean Expressions

3.2 if Statements and Control Flow

3.3 if-else Statements

3.4 else if Statements

3.5 Compound Boolean Expressions

3.6 Equivalent Boolean Expressions

3.7 Comparing Objects

Comparing Objects with == and !=

Comparing Using .equals()

Comparing Strings

Comparing Rectangles

Null Test

Identify Aliases

Check Your Understanding

Exercise: Three Strings

4. Iteration

5. Writing Classes

6. Arrays

7. ArrayLists

8. 2D Arrays

9. Inheritance

10. Recursion

Chapter 3

Boolean Expressions and if Statements

3.7 Comparing Objects

Comparing Objects with == and !=

Comparing Using .equals()

Comparing Strings

Comparing Rectangles

Null Test

Identify Aliases

Check Your Understanding

  1. Incorrect Correct No Answer was selected Invalid Answer

Exercise: Three Strings

Vocabulary

Term Definition
Aliases Two object references are considered aliases when they both reference the same object.
Reference equality Equality operator (==) compares the references (addresses in memory) of 2 objects
Logical equality Compares the data of the objects instead of the value of the references. Uses the .equals() method.