"Once a method has been defined in a class, you can make use of the method as follows. First, you may need to import the class itself depending on where it is. For example, suppose that the examples we’ve presented so far are contained in a class named Utils (short for “utilities”) which is in a package named unl.cse . Then in the class in which we want to call some of these functions we would import it using import unl.cse.Utils; prior to the class declaration. Once the class has been imported, we can invoke a method in the class by first referencing the class and using the dot operator to access one of its methods. For example,\n\nint a = 10, b = 20;\n\nint c = Utils.sum(a, b); //c contains the value 30\n\n//invoke a method with literal values:\n\ndouble dist = Utils.getDistance(0.0, 0.0, 10.0, 20.0);\n\n//invoke a method with a combination:\n\ndouble p = 1500.0;\n\ndouble r = 0.05;\n\ndouble monthlyPayment = Utils.getMonthlyPayment(p, r, 60);"