This is a draft cheat sheet. It is a work in progress and is not finished yet.

### Variables

 Type Description Example Value byte 8 bits 0 int Integer 0 double Integers w/ decimals 0.00 boolean Boolean value (True or False) False char Single character ‘a’ String One or more characters “a1:&b!”

### Instantiating

 Primitives int myInt = 12; double myDouble = 2.11; char myChar = ‘c’; Strings String myString = “hello”; Classes MyClass classOne = new MyClass(parameters); MyClass classTwo = new MyClass();

### Getters & Setters

 Getter public int getMyInt() { return myInt; } Setter public void setMyInt(int newInt) { myInt = newInt; }

### Size and Length

 .length() Returns the number of characters in a String object .length() Returns the number of elements in a Array .size() Returns the number of elements in a ArrayList

### Operators

 Operator Description + addition of numbers, concentration of Strings – subtraction * multiplication / division % modulus; find remainder += add and assign numbers, conventrate and assign Strings -= subtract and assign *= multiply and assign /= divide and assign %= modulus and assign ++ add one — subtract one > greater than < less than >= greater than or equal to <= less than or equal to ! not != not equal to && and || or == comparison = assign

### Loops

 for (int i = 0; i < x; i++) { } for (int i : someArray) { } while (something is true) { }

### Classes

 public class MyClass { private int myInt; private String myString; public MyClass() { myInt = 0; myString = “hello world”; } public MyClass(int i, String s) { myInt = i; myString = s; } }

### Arrays

 int[] myArrayTwo = {1, 2}; ——————— or ——————— int[] myArray = new int[2]; myArray[0] = 1; myArray[1] = 2;

### ArrayList

 .add(obj) Appends obj to end of list .add(index, obj) Inserts obj at position index, moving elements at position index and higher to the right .set(index) Replaces the element at position index with obj; returns the element formerly at position index .get(index) Returns the element at position index in the list

### ArrayList

 .add(obj) Appends obj to end of list. .add(index, obj) Inserts obj at position index, moving elements at position index and higher to the right. .set(index, obj) Replaces the element at position index with obj. .get(index) Returns the element at position index in the list. .remove(index) Removes element from position index, moving elements at position index + 1 and higher to the left and subtracts 1 from size.

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