1- Scjp 6

Front 1

What can identifiers starts with?

Back 1

letter, _ or $

Front 2

how many classes can a souce code file have?

Back 2

only ONE public class. name must match file name.

Front 3

what comes first package or import statement?

Back 3

package then import

Front 4

can a file have more than one non public file?

Back 4

yes

Front 5

what are the three access modifiers?

Back 5

public, protected, private

Front 6

name the access levels

Back 6

public, protected, default, private

Front 7

what access levels can classes have?

Back 7

public, default

Front 8

who can see a default class?

Back 8

classes in the same package

Front 9

who can see a public class?

Back 9

a class from any package

Front 10

name class modifiers

Back 10

final, abstract or strictfp

Front 11

can a class be abstract and final?

Back 11

no

Front 12

can a final class be subclassed?

Back 12

no

Front 13

can an abstract class be instansiated

Back 13

no

Front 14

what does having a single abstract method mean for a class?

Back 14

the whole class must be declared abstract

Front 15

who must implement an abstract classes abstract methods?

Back 15

the first concrete subclass

Front 16

what is an inteface?

Back 16

a contract for what a class can do. no implementation

Front 17

can an interface extend another interface?

Back 17

yes, it can extend many.

Front 18

can a class implement multiple interfaces?

Back 18

yes but only one class.

Front 19

is an interface implicity abstract?

Back 19

yes

Front 20

can an interface have a constant?

Back 20

yes, they are implicity public static and final

Front 21

can a class implementing an interface declare any new checked exceptions for an implementation method?

Back 21

no

Front 22

can a class implementing an interface declare any new runtime exceptions for an implementation method?

Back 22

yes

Front 23

can a class implementing an interface not declare the exceptions of the method in the interface?

Back 23

yes

Front 24

can an interface extend a class?

Back 24

no

Front 25

can a class implementing an interface be abstract?

Back 25

yes

Front 26

what are methods and instances variables known as?

Back 26

members

Front 27

what access level can members have?

Back 27

all four: public, protected, efault, private

Front 28

who can access public members?

Back 28

all classes in all packagages

Front 29

can a subclass inherit a public superclass member

Back 29

yes

Front 30

can a subclass inherit a public superclass member if its in another packages?

Back 30

yes

Front 31

what is 'this.'

Back 31

refers to current object

Front 32

who can access private members?

Back 32

only code in the same class

Front 33

can private members be inherited?

Back 33

no

Front 34

who can access default memebers?

Back 34

classes in the same package

Front 35

who can access protected memebers?

Back 35

classes in the same packages and subclasses in any package

Front 36

what access modifers can a local variable ahve?

Back 36

none

Front 37

can a local variable be final?

Back 37

yes

Front 38

do local variables get default values?

Back 38

no, must be initialised first

Front 39

can final methods be overidden in a subclass?

Back 39

no

Front 40

is the throws clause of an abstract method mandatory?

Back 40

no

Front 41

can a class be synchronized?

Back 41

no

Front 42

what can have synchronized modifier?

Back 42

method, code block only

Front 43

what access levels can a synchronized method have

Back 43

all

Front 44

can a sychnronized method be declared final?

Back 44

yes

Front 45

can abstract methods be private?

Back 45

no

Front 46

can abstract methods be final?

Back 46

no

Front 47

what is a var-arg paramater

Back 47

a param tha accepts from zero to infinte num of args

Front 48

what is the syntax of a var-arg param

Back 48

doStuff(int... x);

Front 49

can a method have multiple var-args params?

Back 49

no

Front 50

if a method has multiple params where does the var-arg have to come?

Back 50

last

Front 51

what acess levels can an instance variable have?

Back 51

public, private, default, protected

Front 52

what other modifiers can an instance variable have?

Back 52

final, transient, volatile
NOT abstract, synchronized, native or strictfp

Front 53

can a local variable have the same name as aninstance variable?

Back 53

yes, it's calling shadowing

Front 54

what are some properties of a final variable?

Back 54

- cant be reinitialized once assigned a value
- can't refer to a diff object once assigned
- must be initialized before constructor completes

Front 55

can the properties of a final obj be changed?

Back 55

yes

Front 56

is an array an object?

Back 56

yes

Front 57

what can ararys hold?

Back 57

primitives or objects

Front 58

how many copies of a static variable are there?

Back 58

one, all instances share it

Front 59

can static methods access non-static members?

Back 59

no

Front 60

what is an enum?

Back 60

a list of constant values assigned to a type

Front 61

is an enum an int

Back 61

no

Front 62

can an enm be declared inside a class?

Back 62

yes

Front 63

can an enum be declared inside a meothd?

Back 63

no

Front 64

what can an enum contain?

Back 64

constructors, methods, variable and constant class bodies

Front 65

can enum constructors have arguments?

Back 65

yes

Front 66

can an enum have an overloaded constructor?

Back 66

no

Front 67

what is MyEnum.values()

Back 67

returns an array of MyEnum's values