Java The Complete Reference, Seventh Edition

public static void main(String args[]) {

X x = new X();

Y y = new Y();

Class<?> clObj;

clObj = x.getClass(); // get Class reference

System.out.println("x is object of type: " +

clObj.getName());

clObj = y.getClass(); // get Class reference

System.out.println("y is object of type: " +

clObj.getName());

clObj = clObj.getSuperclass();

System.out.println("y's superclass is " +

clObj.getName());

}

}

The output from this program is shown here:

x is object of type: X

y is object of type: Y

y’s superclass is X

ClassLoader

The abstract classClassLoaderdefines how classes are loaded. Your application can create

subclasses that extendClassLoader, implementing its methods. Doing so allows you to load

classes in some way other than the way they are normally loaded by the Java run-time system.

However, this is not something that you will normally need to do.

Math

TheMathclass contains all the floating-point functions that are used for geometry and

trigonometry, as well as several general-purpose methods.Mathdefines twodouble

constants:E(approximately 2.72) andPI(approximately 3.14).

Transcendental Functions

The following methods accept adoubleparameter for an angle in radians and return the

result of their respective transcendental function:

Method Description

static double sin(doublearg) Returns the sine of the angle specified byargin radians.

static double cos(doublearg) Returns the cosine of the angle specified byargin radians.

static double tan(doublearg) Returns the tangent of the angle specified byargin radians.

418 Part II: The Java Library