AP CSA Prep

[emmaxshen]

U1 Primitive Types

Primitive type: BASIC data types in Java, representing fundamental values

• *int: Represents a signed 32-bit integer value
• *boolean: Represents true or false values
• *double: Represents a double-precision 64-bit floating-point value
• byte: Represents a signed 8-bit integer value
• short: Represents a signed 16-bit integer value
• long: Represents a signed 64-bit integer value
• float: Represents a single-precision 32-bit floating-point value
• char: Represents a single Unicode character

Reference Data types: more COMPLEX data types, hold collection of values/custom-defined entities

• *String: Sequence of characters
• *Array: Collection of elements of the same data type
• *Class: Define custom data structures that may contain primitives, strings, enums, wrapper classes, or arrays
• *Collection Framework: Object that hold references to other objects.

Hybrid data types:

• *Wrapper classes: Represents primitive data types as objects (if want to store in collection)
• Enums: Represents fixed set of constants that are unchangeable.

Scanner is java utility class for console input + System.out.println(""); for output

U5 Menu Class

• Class is template for an object. Object is instances of a class

[emmaxshen]

Exam questions

4 types

1. Methods and Control Structures
2. Class Implementation
3. Array/ArrayList
4. 2-D Array

Methods & Control Structures