| Keyword |
Description |
abstract |
Used to modify a class or a method. |
boolean |
It is a Java primitive type. A boolean variable may take on one of the values true or false. |
break |
Used to prematurely exit a loop or to mark the end of a case block in a switch statement. |
byte |
It is a Java primitive type. A byte can store an integer value in the range [128, 127]. |
case |
Used to label each branch in a switch statement. |
catch |
Used to define exception handling blocks in try? catch? finally statements. |
char |
It is a Java primitive type. It can store unsigned single unicode character. |
class |
Used to declare a new Java class, which is a collection of related variables and/or methods. |
continue |
Used to the next iteration of a for, while, or do loop. |
default |
Used to label the default branch in a switch statement. |
do |
Specifies a loop whose condition is checked at the end of each iteration. |
double |
It is a Java primitive type. A double variable may store a double precision floating point value. Since floating point data types are approximations of real numbers, you should generally never compare floating point numbers for quality. |
else |
Used in association with the if keyword in an if-else statement. |
extends |
Used in a class or interface declaration to indicate that the class or interface being declared is a subclass of the class or interface whose name follows the 'extends' keyword. |
false |
Represents one of the two legal values for a boolean variable. |
final |
May be applied to a class, indicating the class may not be extended (subclassed). |
finally |
Used to define a block that is always executed in a try? catch? finally statement. |
float |
It is a Java primitive type. To specify a single? Perception literal value, follow the number with f or F, as in 0.01f. |
for |
Specifies a loop whose condition is checked before each iteration. |
if |
Indicates conditional execution of a block. |
implements |
Used in a class declaration to indicate that the class declared provides implementations for all methods declared in the interface whose name follows the implements keyword. |
import |
Makes one class or all classes in a package visible in the current Java source file. |
instanceof |
Used to determine the class of an object. |
int |
It is a Java primitive type. An int variable may store a 32-bit integer value. The integer class is a wrapper class for the int primitive type. |
interface |
Used to declare a new Java interface, which is a collection of methods. |
long |
It is a Java primitive type. A long variable may store a 64-bit signed integer. |
Native |
May be applied to a method to indicate that the method is implemented in a language other than Java. |
new |
Used to create a new instance of a class. |
null |
It is a Java reserved word representing no value. |
package |
Specifies the Java package in which the classes declared in a Java source file reside. |
private |
It is an access control modifier that may be applied to a class, a method or a field (a variable declared in a class). It specifies that the member can only be accessed in its own class. |
protected |
It is an access control modifier that may be applied to a class, a method or a field (a variable declared in a class). It specifies that member can only be accessed within its own package, and in addition, by a subclass of its class in another package. |
public |
It is an access control modifier that may be applied to a class, a method or a field (a variable declared in a class). |
return |
Used to cause a method to return to the method that called it, passing a value that matches the return type of the returning method. |
short |
It is a Java primitive type. A short variable may store a 16-bit signed integer. |
static |
May be applied to an inner class (a class defined within another class), method or field (a member variable of a class). |
super |
Refers to the superclass of the class in which the keyword is used. super as a stand-alone statement represents a call to a constructor of the superclass. super.<methodName>() represents a call to a method of the superclass. |
switch |
Used to select execution of one of multiple code blocks based on an expression. |
synchronized |
May be applied to a method or statement block and provides protection for critical sections that should only be executed by one thread at a time. |
this |
Refers to the current instance. The 'this' keyword is used to refer to the current instance when a reference may be ambiguous. |
throw |
Used to raise an exception. Any method that throws an exception that is not a RuntimeException must also declare the exceptions it throws using a throws modifier on the method declaration. |
throws |
May be applied to a method to indicate the method raises particular types of exceptions. |
transient |
May be applied to member variables of a class to indicate that the member variable should not be serialized when the containing class instance is serialized. |
try |
Used to enclose blocks of statements that might throw exceptions. |
true |
Represents one of the two legal values for a boolean variable. |
void |
Represents a null type. It may be used as the return type of a method to indicate the method does not return a value. |
volatile |
Used to indicate a member variable that may be modified asynchronously by more than one thread. |
while |
Specifies a loop that is repeated as long as a condition is true. |
