java

1
???? ?????? ? java

• ????? ????? ????? ????? 5
• ????? ????? ?????

2
????? ??? ???

• ???? ????? ??? ?????? 3 BFS
• ???? ?? ????? 4 ?'
• ????? (????), polymorphism, instanceof
• ????? '?????' ???? ?????? ?????.
• ???? ????????? ??????.

3
????? - ????????

• ??? ????????? ??????? ?? ????? ????? ?????.
• ?????? ??????? ??? ???????.
• ?????? ???? ????? ??? ??????.
• ????? ??? (???? ???? ?? windows).
• ???? ???? ?? ????.

4
????? 3 ???? ????? ???

• ???? ????? ??? ??? ?????? dist(p1, p2)
• ???? ?????? ??? ??????? ?????? p1,
• ???? ?????? ????? ????? ??????? ?????? ??????.
• ???? ??? ??? ??? '??? ??????' ???? ? p2.
• ???? ?????? BFS (????? ????).

5
????? 4?'

• ?????
• ????? ?????, ?????
• ??????

6
????? - ??????? ?? ???????

• ??? ?????? ???? ????? ??? ??????? ???? ?????.
• ??? ?????? ??? ??? ?????? ????? ???? ??? ?????
  ?? ??????.
• ??? ???? ?????? ???? ???? ?? ?????????

7
??????? ?? ?????? - ?????

• ????? ???? ???? ?? ???? (???? ???? ?????)
• ????? ??? ?????? ???? ????? (??? ?????)
• ????? ?? ?????? ???? ????? 4

8
??????? ?? ?????? - ?????

• ???? ?????? ????? ????????? ??????? ?????
• ????? ????? ?????.
• Shape sp new Shape4
• sp0 new Rect()
• sp1 new Circle(new Point(1,1),4)
• sp2 new Shape()
• ???? ????? ?? ?????? ????? ????, ??????,

9
??????? ?? ?????? - ?????

• ?????? Shape, ???? ????? ??? ?????
• ?????
• ???, ????, toString()
• ??? ?????, ????? ???..
• ????? Constructor
• ???? ??? (???? ???? ?? int)

10
??????? ?? ?????? - ?????
public class Shape private int
_color public Shape(int c) this._color
c public void setColor(int c)this._color
c public int getColor() return
_color public double area() ??? return 1
11
?????? Circle ????? ? Shape

• ????? ?????
• ???, toString
• ??? ???? ???? ?????

class Circle extends Shape public double
area() // over riding!! return
Math.PI_radiud_radius public String
toString() return Circle
cen_center rad _darius // class
Circle
12
????? ????

• ?? ????? ????? ???? ???? ?????? ??? color
• ???? ????? ??????? ??????? ???? ???? ???????
  ??????? - area().
• ??? ????? ???? ?? ?????? ???? ?????? ?????
  (????? ????? ?????? extends ?????? ??????).

13
????? ????

• ???? ???? ?? ????!! ??? ???? ?????? ?? ???? ????
  ????? ???? ????? ????? ?? ????? ???? ?????!
• ? java ????? ????? ???? ?????? ??? ????!.
• ?????? ???? ????? ???? super (????? ? this)

14
?????? Circle ????? ? Shape
??? ????? ??? ???? ???? ?? ???? ???? ?? ?????
????
class Circle extends Shape public
Circle(point p, double r, int color)
super(color) // must be the first line!
// class Circle

• ???? ?? ????? ????? ???? ?????
• ??????? ????? ????? ???? ???!!

15
????? ?????? ?????? ??????

• Java ????? (???? ????) ?? ??????? ????? ????? ???
  ????.
• ???? ????? ???? ?? ???????
• ???? ??? ????? ????? ?????? (????? ????????)
• ?? ?? ???? ???? ??? ?????? ???? ???? (??? ????).
• ??????? ??? ???? poly-morphism ?????
• ????? ?? ???? ?? ????? ????? ?????? ?? ???? ?? ??
  ???? ????? ?????? ???? ?? ???????? ??????!!

16
????? ?????? ?????? ??????

• ??? ?? ???????
• ???? ?? ??? ?? ?????? ????? (???? ???? ????? ???
  ??????)
• ?????? ????? ?????? ????????, ?????? ???? ???????
  ?????? (?????? ??? \ ????? ????? ????).

17
????? ??????? ???? ???

• ??? ???? ???? ??? ?????? ???? ??? ??????? ??
  ???? ????? ?? ?????? (????? ?? ??????? ???????).
• ????? ???? ?????? instanceof, ?????
• if(arri instanceof Circle)
• instanceof ??????? ?????? ????? ??????? (?????)
  ?????? (?????) ????? ??? ?? ???????? ????
  ?????? ?? ??????.
• ???? ?? ????? ??? ????? ???? ???
• If(arri instanceof Shape)

18
????? ??????? ???? ???

• ????????? ???? ???? ?? ???? ???? ?? ????? ??????
  ???? ?? ????? ????? ??? ?????? ?????? ?? ????
  ???? ????, ?????? ???????.
• ?????
• if(arri instanceof Circle) // run time.
• Circle c (Circle)arri // compile time.
• double rad c.radius() // return this radius
• double rad2 arri.radius() // Error (compile
  time)
• //.

19
????? ??????? ???? ??? - Object

• ?? ???????? ??? ??????? ?????? ? Object
• ???? ????? ???? Object arr new Object5
• ???? ?????? ?? ????? ?? ????? (?????? ??????? ..)
• ? Object ???? ????? ???? toString()
• ????? ?????? ?? ?????? Object (java api)
• ?? ??????? ???? ?????? Object!

20
???? ???? ???? - Collection

• ????? ?????? Object ??? ?????? ???? ????
  (vector)
• ?????
• ?????
• ?????
• ????
• ????? ????? ???????, ????????? \ ????

21
???? ???? ???? - Collection
public class MyVector // data members
public static final int INIT_SIZE10,
RESCALE10 private int _sp0 private
Object _objs / Constructors creates a
empty set / public MyVector() _sp0 _obj
s new ObjectINIT_SIZE
22
????? ????? - ???????

• ???? ????? ????? ?????? ???????.
• ??? ??????, ?????.
• ???? ??????
• ??? ?????? f(x)
• ????? ???????? integral(from, till, epsilon)
• ????? ???? ????? root1(from, till)

23
????? ????? - ???????

• ???? ????? ???? ?????? ??????? ????????
• ????? (Monom) f(x) aXb
• ??????? (Polynum) ???? ?? ???????.
• ??????? ?????????, ???? f(x) sin(x)
• ???? ?? ???????? (Sum_f) f(x) S f(x)
• ???? ?? ???????? ???? ???? ???? ?? Sun_f.

24
????? ????? - ???????

• ??????? ?? ??????
• ???? ???
• ??? ?????? (?????) f(x)
• ??????? integral(from,to,eps)
• ???? root(x1,x2)

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????? ????? Function1
public class Function1 / present a common
epsilon for numeric calcs / public static final
double EPS 0.001 public Function1() //
empty constructor public double f(double x)
return 0 // not in use!
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????? ????? Function1
double integral(double from, double till, double
eps) double ans 0 for(double x from
xlttill-eps xxeps) double y1
this.f(x), y2 this.f(xeps) double ym
(y1y2)/2 ans Math.abs(epsym) retu
rn ans
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????? ????? Function1
double root1(double x1, double x2) if(f(x1)
f(x2) gt0) System.out.println(" ERR wrong
values for root f("x1""f(x1)" ,
f("x2")"f(x2)) return -1 // may lead
to a BUG!! return root1(x1,x2,EPS)
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????? ????? Function1
/ recursive / private double root1(double
x1, double x2, double eps) double xm
(x1x2)/2 if(Math.abs(f(xm))lteps) return
xm if(f(xm)f(x1) lt 0) return root1(x1, xm,
eps) return root1(xm, x2, eps)
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????? ????? Function1
private double root2(double x1, double x2,
double eps) double xm (x1x2)/2 while(Mat
h.abs(f(xm))gteps) if(f(xm)f(x1) lt 0)
x2xm else x1xm xm (x1x2)/2 ret
urn xm
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????? ????? Monom
/ this class represent a Monom aXb, / class
Monom extends Function1 private double
_mekadem private int _power public
Monom(double mek, int pow) _mekadem mek
_power pow public double f(double x)
return Math.pow(x,_power) _mekadem
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????? ????? Monom
public void add(Monom m) if(this.equals(m))
_mekadem_mekademm.getMekadem() public void
mul(Monom m) _mekadem_mekadem
m.getMekadem() _power _power
m.getPower() String toString() return
_mekadem"X"_power
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????? ????? Sin_X
// Note no data! class Sin_X extends
Function1 public Sin_X() super() public
double f(double x) return Math.sin(x) //
debug public
String toString() return "sin(x)"
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????? ????? FunctionContainer
public class FunctionContainer extends
MyVector // no data members public
FunctionContainer() super() / overrides!,
only Functions1 can be added / public void add
(Object p) if(p instanceof Function1)
super.add(p) else System.out.println(" ERR
can not add "p" it is not a Function! ")
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????? ????? Sum_f
public class Sum_f extends Function1 private
FunctionContainer _funcs public Sum_f()
super() _funcs new FunctionContainer()
public void add(Function1 f) _funcs.add(f)
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????? ????? Sum_f
public double f(double x) double ans
0 for(int i0ilt_funcs.size()ii1) ans
_funcs.at_f(i).f(x) return ans public
int size() return _funcs.size() public
Function1 at(int i) return _funcs.at_f(i)
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????? ????? Polynom
class Polynom extends Sum_f // which extends
Func. public Polynom() super() public
void add(Function1 t) //overrides
Sum_f.add if(t!null t instanceof Monom)
super.add(t) else System.out.println("
ERR can add only Monoms ")
37
????? ????? Class14
Monom m1 new Monom(.5,1) // f(x)
0.5X Sin_X sin1 new Sin_X() // f(x)
sin(x), radians! MyFrame win new
MyFrame() win.add(m1) win.add(sin1)
win.show()
38
????? ????? ????

• f(x) 0.5x
• f(x) sin(x) , radians

39
????? ????? ????

• f(x) 0.5x
• f(x) sin(x)0.5x
• f(x) 0.1x2
• f(x) 0.1x20.5x

40
????? ????? ????
SOP("Poly "p1" p(2)"p1.f(2)) SOP("Integral(
2,4) "p1.integral(2,4,0.01)) SOP("sin(x)0,
x"sin1.root1(2,4)) // IP
41
???? ????? ?????

• ???? 1 ????? ????? ???? Sum_f (??????? ???
  ????).
• ???? 2 ?????? ???? ????? ??? ???? ???.
• ???? 3 ????? ?????? ???? ?????
  Function1.f(x)
• ????? ????? ??????? ?"? javadoc api.
• ????? ??? ?????, ????? ???.
• ??? ???? ?? ?????? class13.zip

42
?????? ??? ???? ????????

• ???? ????? ?? ??????? ?????? ?????!
• ???? ??????? ???? (?? ???????), ?????? ????????
  ????? ????? (????? ?????) ??? ????? ????? ???
  ????? ???? ?? ????????, ????? ?? ???? this.
• ??????? ????? ???? ?????? ?? ?? ??????? (???? ???
  ???? ????? ?? this).

43
???? ????????? ??????

• ???? ????? ????? ?????? ?? ??????? (????? ??
  this).
• ???? ?????? ????? ??????? ???? ?????? ???? ???.
• ???? ??? ??? ???? ??? ???????? ????? ??????
  ???????
• ???? ???? ???? ????? ?????? ??? ??????? ??? ????
  ???? ???? ???? ?????? (?? ??????? ???? ????
  ?????? ????).
• ??????? ????? ???? ????? ?? this ???? ?????
  ????? ?? ?? ???? ???? ?? ??????.

44
???? ????????? ?????? - ?????

• public class Shape
• private static int _counter 0
• private int _color
• public Shape(int c)
• this._color c
• _counter
• public static int instances() return _counter

45
?? ????? ????

• ?????
• ???? ?????? ??????, polymorphism, casting.
• ????? ????? ????????.
• ???? ?????? ?????
• ????? ????? ?????? ??????? ??????????.
• ????? ????? ??????? (??? ????? ?????).
• ???? ????????? ??????.