Declaring Multiple Variables in Java: Syntax and Examples

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問題：

Introduce Java Declare Multiple Variables and give examples

答案：

In Java, you can declare multiple variables of the same type in a single statement, which can help make your code more concise and readable. This is particularly useful when you need to initialize several variables that share the same data type.

Syntax for Declaring Multiple Variables

The general syntax for declaring multiple variables of the same type is as follows:

dataType variable1, variable2, variable3, ...;

Examples

  1. Declaring Multiple Integer Variables:
int a, b, c;
a = 5;
b = 10;
c = 15;

You can also initialize them at the time of declaration:

int x = 1, y = 2, z = 3;
  1. Declaring Multiple Double Variables:
double length, width, height;
length = 5.5;
width = 3.2;
height = 4.8;

Or initializing them directly:

double radius = 2.5, area = 3.14 * radius * radius, circumference = 2 * 3.14 * radius;
  1. Declaring Multiple String Variables:
String firstName, lastName, fullName;
firstName = "John";
lastName = "Doe";
fullName = firstName + " " + lastName;

Or initializing them directly:

String city = "New York", country = "USA", continent = "North America";
  1. Declaring Multiple Boolean Variables:
boolean isActive, isVerified, isAdmin;
isActive = true;
isVerified = false;
isAdmin = true;

Or initializing them directly:

boolean isAvailable = true, isOnSale = false, isFeatured = true;

Important Notes

  • All variables declared in a single statement must be of the same type.
  • You can also declare multiple variables and initialize them in a single line, but be cautious about readability, especially if the initial values are complex.
  • If you need to declare variables of different types, you must do so in separate statements.

Conclusion

Declaring multiple variables in Java can help streamline your code and improve its readability. However, it's essential to balance conciseness with clarity to ensure that your code remains understandable.

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