Which keyword is used to define a constant in Java?

In Java, the keyword used to define a constant is "final." When you declare a variable with the final keyword, it means that once the variable is initialized with a value, it cannot be modified. This is crucial for defining constants in Java because it ensures that the constant's value remains unchanged throughout the program, providing reliability and prevent accidental changes to important values.

For example, if you define a constant for the value of Pi like this:

final double PI = 3.14159;

The variable PI cannot be reassigned to a different value later in the code, thus maintaining its integrity as a constant.

The other options are not correct in this context. The keyword "const" is not used in Java at all, even though it is present in other programming languages like C++ for defining constants. The term "static" refers to a class-level variable or method that can be accessed without needing to create an instance of the class, and although static variables can also be constants if combined with final, static alone does not inherently define a constant. The term "constant" is not a recognized keyword in Java for defining constants. Therefore, using final is the only correct approach to creating constants in Java.