Complete list of java keywords

 

1. abstract -Specifies that a class or method will be implemented later, in a subclass
2. assert -Assert describes a predicate (a true–false statement) placed in a Java program to indicate that the developer thinks that the predicate is always true at that place. If an assertion evaluates to false at run-time, an assertion failure results, which typically causes execution to abort.
3. boolean – A data type that can hold True and False values only
4. break – A control statement for breaking out of loops
5. byte – A data type that can hold 8-bit data values
6. case – Used in switch statements to mark blocks of text
7. catch – Catches exceptions generated by try statements
8. char – A data type that can hold unsigned 16-bit Unicode characters
9. class -Declares a new class
10. continue -Sends control back outside a loop
11. default -Specifies the default block of code in a switch statement
12. do -Starts a do-while loop
13. double – A data type that can hold 64-bit floating-point numbers
14. else – Indicates alternative branches in an if statement
15. enum – A Java keyword used to declare an enumerated type. Enumerations extend the base class.
16. extends -Indicates that a class is derived from another class or interface
17. final -Indicates that a variable holds a constant value or that a method will not be overridden
18. finally -Indicates a block of code in a try-catch structure that will always be executed
19. float -A data type that holds a 32-bit floating-point number
20. for -Used to start a for loop
21. if -Tests a true/false expression and branches accordingly
22. implements -Specifies that a class implements an interface
23. import -References other classes
24. instanceof -Indicates whether an object is an instance of a specific class or implements an interface
25. int – A data type that can hold a 32-bit signed integer
26. interface – Declares an interface
27. long – A data type that holds a 64-bit integer
28. native -Specifies that a method is implemented with native (platform-specific) code
29. new – Creates new objects
30. null -Indicates that a reference does not refer to anything
31. package – Declares a Java package
32. private -An access specifier indicating that a method or variable may be accessed only in the class it’s declared in
33. protected – An access specifier indicating that a method or variable may only be accessed in the class it’s declared in (or a subclass of the class it’s declared in or other classes in the same package)
34. public – An access specifier used for classes, interfaces, methods, and variables indicating that an item is accessible throughout the application (or where the class that defines it is accessible)
35. return -Sends control and possibly a return value back from a called method
36. short – A data type that can hold a 16-bit integer
37. static -Indicates that a variable or method is a class method (rather than being limited to one particular object)
38. strictfp – A Java keyword used to restrict the precision and rounding of floating point calculations to ensure portability.
39. super – Refers to a class’s base class (used in a method or class constructor)
40. switch -A statement that executes code based on a test value
41. synchronized -Specifies critical sections or methods in multithreaded code
42. this -Refers to the current object in a method or constructor
43. throw – Creates an exception
44. throws -Indicates what exceptions may be thrown by a method
45. transient -Specifies that a variable is not part of an object’s persistent state
46. try -Starts a block of code that will be tested for exceptions
47. void -Specifies that a method does not have a return value
48. volatile -Indicates that a variable may change asynchronously
49. while -Starts a while loop

** The keywords const and goto are reserved, even they are not currently in use.

• const -Reserved for future use
• goto – Reserved for future use

** true, false and null look like keywords, but in actual they are literals. However they still can’t be used as identifiers in a program.