Java Reference
In-Depth Information
2. Model part of an animal hierarchy by declaring
Animal
,
Bird
,
Fish
,
AmericanRobin
,
DomesticCanary
,
RainbowTrout
, and
Sock-
eyeSalmon
classes:
•
Animal
is
public
and
abstract
, declares
private String
-based
kind
and
appearance
fields,declaresa
public
constructorthatinitial-
izesthesefieldstopassed-inarguments,declares
public
and
abstract
eat()
and
move()
methodsthattakenoargumentsandwhosereturntype
is
void
,andoverridesthe
toString()
methodtooutputthecontentsof
kind
and
appearance
.
•
Bird
is
public
and
abstract
, extends
Animal
, declares a
public
constructor that passes its
kind
and
appearance
parameter values to
its superclass constructor, overrides its
eat()
method to output
eats
seeds and insects
(via
System.out.println()
),andoverrides
the
move()
method to output
flies through the air
.
•
Fish
is
public
and
abstract
, extends
Animal
, declares a
public
constructor that passes its
kind
and
appearance
parameter values to
its superclass constructor, overrides its
eat()
method to output
eats
krill, algae, and insects
,andoverridesits
move()
methodto
output
swims through the water
.
•
AmericanRobin
is
public
,extends
Bird
,anddeclaresa
public
noar-
gumentconstructorthatpasses
"americanrobin"
and
"red breast"
to its superclass constructor.
•
DomesticCanary
is
public
, extends
Bird
, and declares a
public
noargumentconstructorthatpasses
"domesticcanary"
and
"yellow,
orange, black, brown, white, red"
toitssuperclassconstruct-
or.
•
RainbowTrout
is
public
, extends
Fish
, and declares a
public
noar-
gument constructor that passes
"rainbowtrout"
and
"bands of
brilliant speckled multicolored stripes running
nearly the whole length of its body"
toitssuperclasscon-
structor.
•
SockeyeSalmon
is
public
,extends
Fish
,anddeclaresa
public
noar-
gument constructor that passes
"sockeyesalmon"
and
"bright red
with a green head"
to its superclass constructor.
