O'Reilly logo

Java in a Nutshell, 5th Edition by David Flanagan

Stay ahead with the world's most comprehensive technology and business learning platform.

With Safari, you learn the way you learn best. Get unlimited access to videos, live online training, learning paths, books, tutorials, and more.

Start Free Trial

No credit card required

Numbers and Math

Java provides the byte, short, int, long, float, and double primitive types for representing numbers. The java.lang package includes the corresponding Byte, Short, Integer, Long, Float, and Double classes, each of which is a subclass of Number. These classes can be useful as object wrappers around their primitive types, and they also define some useful constants:

// Integral range constants: Integer, Long, and Character also define these
Byte.MIN_VALUE      // The smallest (most negative) byte value
Byte.MAX_VALUE      // The largest byte value
Short.MIN_VALUE     // The most negative short value
Short.MAX_VALUE     // The largest short value

// Floating-point range constants: Double also defines these
Float.MIN_VALUE     // Smallest (closest to zero) positive float value
Float.MAX_VALUE     // Largest positive float value

// Other useful constants
Math.PI             // 3.14159265358979323846
Math.E              // 2.7182818284590452354

Mathematical Functions

The Math class defines a number of methods that provide trigonometric, logarithmic, exponential, and rounding operations, among others. This class is primarily useful with floating-point values. For the trigonometric functions, angles are expressed in radians. The logarithm and exponentiation functions are base e, not base 10. Here are some examples:

double d = Math.toRadians(27); // Convert 27 degrees to radians d = Math.cos(d); // Take the cosine d = Math.sqrt(d); // Take the square root d = Math.log(d); // Take the natural logarithm d = ...

With Safari, you learn the way you learn best. Get unlimited access to videos, live online training, learning paths, books, interactive tutorials, and more.

Start Free Trial

No credit card required