Java Keywords
Access Control
| Access Levels Modifier | Class | Package | SubClass | World |
|---|---|---|---|---|
| private | Y | Y | N | N |
| protected | Y | Y | Y | Y |
| public | Y | Y | Y | Y |
| (default) | Y | Y | N - different package Y - same package | N |
Class & Variable & Methods
| Modifier | Description |
|---|---|
| class | |
| interface | |
| default | default declare a default method in an interface |
| enum | |
| abstract | |
| extends | |
| implements | |
| final | |
| static | |
| var | New from Java 10 |
| new | |
| native | |
| volatile | |
| synchronized | |
| transient | |
| strictfp |
Flow Control
| Keyword | Remark |
|---|---|
| for | |
| if | |
| else | |
| while | |
| switch | |
| case | |
| break | Used in while, for, switch |
| return | |
| continue | |
| do | |
| instanceof |
Error Handle
| Keyword | Remark |
|---|---|
| try | |
| catch | |
| finally | |
| throw | |
| throws |
Package Imports
| Keyword | Remark |
|---|---|
| import | import a package |
| package | declare a package name |
Variable Reference
| Keyword | Remark |
|---|---|
| super | Used to invoke or reference to parent's method or variable |
| this | Used to invoke or reference to current class' method or variable |
Operators
| Keyword | Remark |
|---|---|
| . | Access a variable's method or variable |
| ++ | a++ or ++a |
| -- | a-- or --a |
| + | |
| - | |
| \(*\) | |
| / | divide |
| | | |
| || | |
| & | |
| && | |
| ^ | |
| % | |
| ! | |
| = | |
| ? : | |
Reserved
| Keyword | Remark |
|---|---|
| goto | Not used in Java, but kept as a keyword |
| const | Not used in Java, but kept as a keyword |