Java Programming Cheatsheet

We summarize the most commonly used Java language features and APIs in the textbook.

Hello, World.

Hello, World in Java

Editing, compiling, and executing.

Compiling Hello, World in Java

Built-in data types.

Built-in types of data

Declaration and assignment statements.

Assignment statements


int data type

Integer expressions

Floating-point numbers.

double data type

double expressions


boolean data type

Boolean operators

Comparison operators.

Comparison operators

Comparison examples



Parsing command-line arguments.

parsing Command-line arguments

Math library.

Math library API
The full java.lang.Math API.

Java library calls.

Expressions that use Java library methods

Type conversion.

Type conversion

Anatomy of an if statement.

anatomy of an if statement

If and if-else statements.

If-else statements

Nested if-else statement.

Nested if-else statements in Java

Anatomy of a while loop.

While loop

Anatomy of a for loop.

For loop


While and for loops in Java

Break statement.

Break statement in Java

Do-while loop.

Do-while loop in Java

Switch statement.

Switch statement in Java


An array

Inline array initialization.

Inline initialization of arrays
Typical array-processing code.
Typical array-processing code

Two-dimensional arrays.

2D array
Inline initialization.
2D array inline initialization

Our standard output library.

Standard output API
The full StdOut API.

Formatted printing.

Anatomy of printf
Formatting codes for printf

Our standard input library.

Standard input API
The full StdIn API.

Our library for array input and output.

array input and output
The full StdArrayIO API.

Our standard drawing library.

Standard drawing API
The full StdDraw API.

Our standard audio library.

Standard audio API
The full StdAudio API.

Our standard picture library.

Standard picture API
The full StdPicture API.

Command line.

command line

Redirection and piping.

Redirecting standard output                Redirecting standard input



Anatomy of a function

Example functions

Libraries of functions.

Library abstraction

Our standard random library.

Standard random
The full StdRandom API.

Our standard statistics library.

Standard statistics
The full StdStats API.

Using an object.

Using an object

Instance variables.

Anatomy of instance variables


Anatomy of a constructor

Instance methods.

Anatomy of an instance method


Anatomy of a class

Object-oriented libraries.

Object-oriented library abstraction

Java's String data type.

String library API
The full java.lang.String API.
String operations

Java's Color data type.

Color library API
The full java.awt.Color API.

Our input library.

Input API
The full In API.

Our output library.

Output API
The full Out API.

Our picture library.

Picture API
The full Picture API.

Our stack data type.

Stack API
The full Stack API.

Our queue data type.

Queue API
The full Queue API.


Anatomy of an iterable

Our symbol table data type.

Symbol Table API
The full ST API.

Our set data type.

The full SET API.

Our graph data type.

Graph API
The full Graph API.

Compile-time and run-time errors.

Here's a list of errors compiled by Mordechai Ben-Ari. It includes a list of common error message and typical mistakes that give rise to them.