CIS 160 Methods

Creating a method

syntax for method creation: [modifiers] datatype method_name(parameter_list) { [statements] [return [value];] }
all parameters in list act as variables and must each have a data type and a valid name
parameters which are a built-in (primitive) data type are passed by-value, which means a copy of their value is placed in a new local variable and changing their value within the method does not change their value outside the method
parameters which are not a built-in (primitive) data type are passed by-reference, which means that changing their value within the method may change their value outside the method
multiple methods may have the same name if they have parameter lists that differ substantively within the parameter list
a single value may be returned using the return statement; the data type of the value being returned must be compatible with the data type in the method signature
variables declared within a method can only be seen within a method; these are called local variables
variables declared outside of a method, but within a class, can be seen by all methods in that class; these are called global variables
variables declared within a method are destroyed when the method is finished executing
methods may call themselves; these are called recursive methods

syntax: [varname =] methodname(argument_list);
the argument list is a comma separated list of values (which can, and often does, include variable names)
the arguments must match the parameter list in the method being called
if a value is returned from a method, it may be stored in a variable, used in an expression, or used as an argument in another method call