Java keywords

In Java, keywords are reserved words that have a predefined meaning in the language. They form the foundation of Java's syntax and cannot be used as identifiers, such as variable names, method names, or class names.

Each keyword has a specific function, and the Java compiler uses these to parse the structure of Java code.

List of Java Keywords

Keyword	Description
abstract	Defines abstract classes and methods.
assert	Used for debugging purposes to test assumptions in the code.
boolean	Defines a boolean variable with true or false values.
break	Exits a loop or a switch statement.
byte	Defines a byte variable (8-bit signed integer).
case	Defines a block of code in switch statements.
catch	Handles exceptions in a try-catch block.
char	Defines a character variable.
class	Declares a class.
continue	Skips the current iteration of a loop and continues.
default	Defines the default block in a switch statement.
do	Executes a block of code at least once in a do-while loop.
double	Defines a double precision floating-point variable.
else	Defines the alternative block for an if statement.
enum	Declares an enumerated type.
extends	Indicates a subclass inherits from a superclass.
final	Defines constants or methods that cannot be overridden.
finally	Ensures code execution after a try-catch block.
float	Defines a floating-point variable.
for	Declares a loop that repeats a block of code.
if	Starts a conditional block.
implements	Indicates that a class implements an interface.
import	Imports classes or entire packages.
instanceof	Tests whether an object is an instance of a specific class.
int	Defines an integer variable.
interface	Declares an interface.
long	Defines a long integer variable.
native	Indicates that a method is implemented in native code.
new	Creates a new object instance.
null	Represents the null reference, no value.
package	Declares a package.
private	Declares a private member, accessible only within its class.
protected	Declares a protected member, accessible within package or subclasses.
public	Declares a public member, accessible by any other class.
return	Exits a method and optionally returns a value.
short	Defines a short integer variable.
static	Declares a static member that belongs to the class, not instances.
strictfp	Restricts floating-point calculations to ensure portability.
super	Refers to the superclass of the current object.
switch	Declares a multi-branch conditional statement.
synchronized	Locks a block of code or method to prevent concurrent access.
this	Refers to the current object instance.
throw	Throws an exception.
throws	Declares exceptions that a method can throw.
transient	Marks a field to be skipped during serialization.
try	Starts a block to test for exceptions.
void	Indicates that a method does not return a value.
volatile	Marks a variable as being used by multiple threads.
while	Declares a loop that executes while a condition is true.

Tips and Best Practices

Avoid using Java keywords as variable names: Trying to use a keyword as a variable or identifier will result in a syntax error.
Use meaningful names: When naming classes, methods, or variables, ensure they are descriptive and avoid abbreviations that are unclear.
Keep keywords in mind when working with frameworks: Be mindful of keywords when you generate classes or methods dynamically, especially when using frameworks that auto-generate code.
Organize code using keywords effectively: Make good use of keywords like final, synchronized, and volatile in multithreaded applications for thread safety and performance.