Java - Chapter 5

Two important points to remember about @param:

1) All @param tags must appear after the general description of the method, 2) the description can span several lines. It ends at the end of the documentation comment or at the beginning of another tag.

General format of @param

@param parameterName Description

lifetime of a local variable

A function's local variables exist only while the function is executing; any value stored in a local variable is lost between calls to the method in which the variable is declared.

void method

A method that does not return a value; simply performs a task and then terminates.

divide and conquer

A program design strategy in which tasks are broken down into subtasks, which are broken down into sub-subtasks, and so on, until each piece is small enough to code comfortably. These pieces work together to accomplish the total job.

method header

Appears at the beginning of a method definition, lists several important things about the method, including the method's name.

There is a need for a method that tests an argument and returns a true or false value indicating whether or not a condition exist. This will return a ____________ value.

Boolean

True or False - You can use the method's return value anywhere you can use a regular value of a different data type.

False - It needs to be the same data type.

@param

Javadoc block tag specifying a variable's name and its description.

@return

Javadoc block tag to describe the return value of a method. @return Description

Layered method calls

Method A can call Method B, which can then call Method C.

functional decomposition

The process of breaking a problem down into smaller pieces.

Return type

The type of data a method gives back.

True of False: A variable is visible only to statements inside the variable's scope.

True

True or False: A value-returning method can also return a reference to a non-primitive type such as a String object.

True

True or False: Each parameter variable in a parameter list must have a data type listed before its name.

True

method body

a collection of statements that are performed when the method is executed

method

a collection of statements that performs a specific task; commonly used to break a problem into small, manageable pieces.

Any time you use the = operator to assign a string literal to a String reference variable:

a new String object is created in memory

When an object, such as String, is passed as an argument, it is:

a reference to the object that is passed

passed by value

all arguments of the primitive data types; only a copy of an argument's value is passed into a parameter variable; a method's parameters variables are separate and distinct from the arguments that are listed inside the parentheses of a method call.

Values that are sent into a method are called ____________.

arguments

return statement

causes the method to end execution and it returns a value to the statement that called the method. return Expression;

local variable

declared inside a method and is not accessible to statements outside of the method

How to call a method named displayMessage?

displayMessage(); it is the name of the method followed by a set of parentheses.

Documentation comments can be read and processed by a program named __________, which produces attractive HTML documentation.

javadoc

Methods can also be called in ________ fashion.

layered

Every complete Java program must have a __________ method.

main

Reference variable holds the ________________ of an object.

memory address

Two parts of a definition

method header and method body

Method name

name that is descriptive of what the method does

Parameter list

passing more than one argument to a method

value-returning method

performs a task, but also sends a value back to the code that called it

You must have a __________ statement in a value-returning method.

return

How to write a method that accepts the two arguments num1 and num2 as integers?

showSum(int num1, int num2)

parameter variable

sometimes referred to as a parameter; is a special variable that holds a value being passed into a method.

When writing a value-returning method, you must:

specify the data type of the return value in the method header

When you pass an argument to a method, be sure that:

the argument's data type is compatible with the parameter variable's data type.

If a method calls another method that has a throws clause in its header, then:

the calling method should have the same throws clause.

method modifiers

the key words public and static. Public means that the method is publicly available to the code outside of the class. Static means that the method belongs to the class, not a specific object.

Parentheses

the method name is always followed by a set of parentheses. If the method is capable of receiving arguments, a list of one or more variable declarations will appear inside the parentheses.

In Java, String objects are immutable, which means:

they cannot be changed

Java will automatically perform a ________________ if the argument's data type is ranked ________ than the parameter's variable's data type.

widening conversion; lower

When passing a variable as an argument, do not:

write the data type of the argument variable in the method call

code reuse

writing the code to perform a task once and then reusing it each time you need to perform the task