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Java Reference

An A-Z lookup of Java keywords, grouped alongside dedicated pages for each commonly used method.

Java Keywords

Java has a set of keywords that are reserved words that cannot be used as variables, methods, classes, or any other identifiers:

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Java Keywords

Java assert Keyword Java abstract Keyword Java boolean Keyword Java break Keyword Java byte Keyword Java case Keyword Java catch Keyword Java char Keyword Java class Keyword Java continue Keyword Java default Keyword Java do Keyword Java double Keyword Java else Keyword Java enum Keyword Java exports Keyword Java extends Keyword Java final Keyword Java finally Keyword Java float Keyword Java for Keyword Java if Keyword Java implements Keyword Java import Keyword Java instanceof Keyword Java int Keyword Java long Keyword Java module Keyword Java native Keyword Java new Keyword Java package Keyword Java private Keyword Java protected Keyword Java public Keyword Java return Keyword Java requires Keyword Java short Keyword Java static Keyword Java super Keyword Java switch Keyword Java synchronized Keyword Java this Keyword Java throw Keyword Java throws Keyword Java transient Keyword Java try Keyword Java var Keyword Java void Keyword Java volatile Keyword Java while Keyword

Math Methods

Java Math abs() Method Java Math acos() Method Java Math addExact() Method Java Math asin() Method Java Math atan() Method Java Math atan2() Method Java Math cbrt() Method Java Math ceil() Method Java Math copySign() Method Java Math cos() Method Java Math cosh() Method Java Math decrementExact() Method Java Math exp() Method Java Math expm1() Method Java Math floor() Method Java Math floorDiv() Method Java Math floorMod() Method Java Math getExponent() Method Java Math hypot() Method Java Math IEEEremainder() Method Java Math incrementExact() Method Java Math log() Method Java Math log10() Method Java Math log1p() Method Java Math max() Method Java Math min() Method Java Math multiplyExact() Method Java Math negateExact() Method Java Math nextAfter() Method Java Math nextDown() Method Java Math nextUp() Method Java Math pow() Method Java Math random() Method Java Math rint() Method Java Math round() Method Java Math scalb() Method Java Math signum() Method Java Math sin() Method Java Math sinh() Method Java Math sqrt() Method Java Math subtractExact() Method Java Math tan() Method Java Math tanh() Method Java Math toDegrees() Method Java Math toIntExact() Method Java Math toRadians() Method Java Math ulp() Method

String Methods

Java String charAt() Method Java String codePointAt() Method Java String codePointBefore() Method Java String codePointCount() Method Java String compareTo() Method Java String compareToIgnoreCase() Method Java String concat() Method Java String contains() Method Java String contentEquals() Method Java String copyValueOf() Method Java String endsWith() Method Java String equals() Method Java String equalsIgnoreCase() Method Java String format() Method Java String getBytes() Method Java String getChars() Method Java String hashCode() Method Java String indexOf() Method Java String isEmpty() Method Java String join() Method Java String lastIndexOf() Method Java String length() Method Java String matches() Method Java String offsetByCodePoints() Method Java String regionMatches() Method Java String replace() Method Java String replaceAll() Method Java String replaceFirst() Method Java String split() Method Java String startsWith() Method Java String subSequence() Method Java String substring() Method Java String toCharArray() Method Java String toLowerCase() Method Java String toString() Method Java String toUpperCase() Method Java String trim() Method Java String valueOf() Method

Scanner Methods

Java Scanner close() Method Java Scanner delimiter() Method Java Scanner findInLine() Method Java Scanner findWithinHorizon() Method Java Scanner hasNext() Method Java Scanner hasNextBoolean() Method Java Scanner hasNextByte() Method Java Scanner hasNextDouble() Method Java Scanner hasNextFloat() Method Java Scanner hasNextInt() Method Java Scanner hasNextLine() Method Java Scanner hasNextLong() Method Java Scanner hasNextShort() Method Java Scanner locale() Method Java Scanner next() Method Java Scanner nextBoolean() Method Java Scanner nextByte() Method Java Scanner nextDouble() Method Java Scanner nextFloat() Method Java Scanner nextInt() Method Java Scanner nextLine() Method Java Scanner nextLong() Method Java Scanner nextShort() Method Java Scanner radix() Method Java Scanner reset() Method Java Scanner useDelimiter() Method Java Scanner useLocale() Method Java Scanner useRadix() Method

LinkedList Methods

Java LinkedList add() Method Java LinkedList add() Method Java LinkedList clear() Method Java LinkedList clone() Method Java LinkedList contains() Method Java LinkedList forEach() Method Java LinkedList get() Method Java LinkedList getFirst() Method Java LinkedList getLast() Method Java LinkedList indexOf() Method Java LinkedList isEmpty() Method Java LinkedList iterator() Method Java LinkedList lastIndexOf() Method Java LinkedList listIterator() Method Java LinkedList remove() Method Java LinkedList removeAll() Method Java LinkedList removeFirst() Method Java LinkedList removeIf() Method Java LinkedList removeLast() Method Java LinkedList replaceAll() Method Java LinkedList retainAll() Method Java LinkedList set() Method Java LinkedList size() Method Java LinkedList sort() Method Java LinkedList spliterator() Method Java LinkedList subList() Method Java LinkedList toArray() Method

ArrayList Methods

HashMap Methods

Java Reference

Java String Methods Java Math Methods Java Output Methods Java Array length Property Java Scanner Methods Java FileInputStream Methods Java FileOutputStream Methods Java BufferedReader Methods Java BufferedWriter Methods Java System Methods

Arrays Methods

Java Arrays. compare() Method Java Arrays. equals() Method Java Arrays. sort() Method Java Arrays. fill() Method

Java Collections

Java ArrayList Methods Java LinkedList Methods Java HashMap Methods Java Collections Class Methods

Output Methods

Java Output print() Method Java Output printf() Method Java Output println() Method

Java Classes

Java Arrays Class Java File Class Methods

Java Interfaces

Java interface Keyword Java Iterator Interface

Java Errors and Exceptions

Java Errors and Exception Types