Exam Essentials 1 bag 41

Question 1

Be able to write code using a main() method.

A main() method is usually written as public static void main(String[] args).

Arguments are referenced starting with args[0]. Accessing an argument that wasn’t passed in will cause the code to ___ an ___

Answer 1

throw and exception

Question 2

Understand the effect of using packages and imports.

A ___ has the same name as the ____.
It looks like a method without a ____ ____

Answer 2

constructor

return type

Question 3

Be able to identify legal and illegal declarations and instantiations.

Multiple variables can be ____ and _____ in the same statement when they share a ___.

Answer 3

declared
instantiated
type

Question 4

___ variables require an explicit initialization.

Answer 4

Local variables

Question 5

_____ may contain:

____, ____, ___ and ___.

Answer 5

Identifiers
letters
numbers
$
_

Question 6

Identifiers may not begin with ____

Answer 6

numbers

Question 7

_____ ____ may contain ____ between numbers.

Answer 7

Number literals

underscores

Question 8

Number literal may begin with
_- _ (decimal)
_ (octal)
\_\_ and \_\_ (hex)
\_\_ and \_\_ (binary)

Answer 8

0-1
0
0x and 0X
0b and 0B

Question 9

Be able to determine where variables go into and out of scope.

All variables go into scope when they are ___.

Answer 9

declared

Question 10

____ variables go out of scope when the block they are declared ___

Answer 10

local

ends

Question 11

____ variables go out of scope when the object is garbage collected.

Answer 11

instance variables

Question 12

___ variables remain in scope as long as the program is running.

Answer 12

class variables

Question 13

An instance variable goes out of scope when the object is ___ ____

Answer 13

garbage collected

Question 14

Class variables remain in scope as long as the ___ is running

Answer 14

program

Question 15

Be able to recognize misplaced statements in a class.

T or F
Package and imports statements are optional.

Answer 15

True

Question 16

In what order does package and imports statement go?

Answer 16

package statement

import statment

Question 17

T or F
Does the package and import statement go after the class declaration?

Answer 17

False.
They go before the class declaration

Question 18

T or F

Are fields and methods optional?

Answer 18

True

Question 19

In what order are fields and methods allowed within the class declaration.

Answer 19

In any order

Question 20

Know how to identify when an object is eligible for garbage collection.

Draw a diagram to keep track of references and objects as you trace the code.

• When no arrows point to a box (object), it is eligible for garbage collection.

Answer 20

:)

You got this!

Question 21

T or F

Identifiers apply to anything you are free to name?

Answer 21

True

Question 22

Whare are examples of identifiers which you are free to name?

Answer 22

variables
methods
classes and
fields

Question 23

What are the only three rules for legal identifiers?

1. The name must begin with a __ or the symbol _ or _.
2. Subsequent characters may also be ___.
3. You cannot use the same name as a Java __ word.

Answer 23

1. The name must begin with a letter, symbol & or underscore.
2. numbers
3. Reserved

Question 24

What is a reserved word?

Answer 24

A reserved word is a keyword that Java has reserved.

You are not allowed to use it.

Question 25

T or False

Java is case sensitive

Answer 25

True

Question 26

Name one reserved word

Answer 26

Class