Since
2008
Since
2008
Since
2008
‘final’ should not be called as constants. Because when an array is declared as final, the state of the object stored in the array can be modified. You need to make it immutable in order not to allow modifcations. In general context constants will not allow to modify. In C++, an array declared as const will not allow the above scenario but java allows. So java’s final is not the general constant used across in computer languages.
A variable that is declared static final is closer to constants in general software terminology. You must instantiate the variable when you declare it static final.
Definition as per java language specification (third edition) – 4.12.4 is “A final variable may only be assigned to once.”(§4.1.2)
Java language specification tries to redefine the meaning of constant in the following way!
We call a variable, of primitive type or type String, that is final and initialized with a compile-time constant expression (§15.28) a constant variable. Whether a variable is a constant variable or not may have implications with respect to class initialization (§12.4.1), binary compatibility (§13.1, §13.4.9) and definite assignment (§16).
Comments are closed for "Java Final Keyword".
can you send me some of the sample program in java to explain java final
please send me my mail id to what is final key word? and example java program esay to understand
java final nicely explained
thanks for the explanation on final keyword in java. please send me more about applet
please send to my mail id some of the sample programs of java using final keyword.
I’ve used variations of question on java final on many interviews – it’s surprising how many head-scratchings you get from something like:
private final List list = new ArrayList();
list.add(“value”);
— does the above work? (e.g. does final keyword make the java collection immutable) or other variations like declaring method inputs final, etc.
exelent defination for java final
jason – private final List list here you are just making a reference list as final, the class ArrayList is not immutable so to have a immutable class you have to have all references immutable too…making it just final won’t make it immutable.
Brief, to-the-point article. Thanks!
Hope this code helps:
class Another
{
final int xyz;
public Another()
{
xyz=1000;
}
public void display()
{
System.out.println(“XYZ=”+xyz);
}
}
public class FinalTest
{
static final int y=3;
public FinalTest()
{
}
static
{
System.out.println(“Just for fun…”);
}
public static void main(String[] args)
{
final int x=5;
System.out.println(“X=”+x);
System.out.println(“Y=”+y);
Another ano=new Another();
ano.display();
}
}
Good desc on java final keyword.. very useful .. :)
Simple explanation …easy understandable…
its really good stuff on one desk to get on for beginer’s knowledge
can any one tel me for how to write a program for multiplication of 200 numbers wid another 200 numbers….plz……help or either giv some basic idea for hw to make dis program …m nt geting it
gud….got basic information about final keyword from it……thank u….
firstly thanks on the explanation on java final keyword. because u explain terms in jsp and servlet very simple language.
please tell me about scriptless jsp.
very nicely explain…thanksss
I want to java program examples on final keywords
please send to my mail id.in final keywords,class variable methods using.pls send to the some example program for this three types. separare example this three words
why could an object in java could not be declared final.
talk.to.shan.now@gmail.com
Send all your problems here..
@HITASHA
import java.io.*;
class mul{
int a=new int[400];
mul()
{}
void mul1()
{
DataInputStream c=new DataInputStream(System.io);
System.out.print(“Enter 1st 200 numbers..\n”);
for(int i=0;i<200;i++)
{
System.out.print("\nEnter"+i+1+" no:");
int p=Integer.parseInt(c.readLine());
a[i]=p;
}
System.out.print("\n\nEnter Next 200 numbers..\n");
for(i=200;i<400;i++)
{
System.out.print("\nEnter"+i+1+" no:");
int p=Integer.parseInt(c.readLine());
a[i]=p;
}
for(i=0;i<400;i++)
{
int s=a[i]*a[i+200];
System.out.print("\nMultiplication of "+i+1+" and "+i+201+" is:"+s);
}
}
public static void main(String arg[]){
talk.to.shan.now@gmail.com
Send all your problems here..
@HITASHA
import java.io.*;
class mul{
int[] a=new int[400];
mul()
{}
void mul1()
{
try{
DataInputStream c=new DataInputStream(System.in);
System.out.print(“Enter 1st 200 numbers..\n”);
for(int i=0;i<5;i++)
{
System.out.print("\nEnter no "+(i+1)+":");
int p=Integer.parseInt(c.readLine());
a[i]=p;
}
System.out.print("\n\nEnter Next 200 numbers..\n");
for(int i=5;i<10;i++)
{
System.out.print("\nEnter no "+(i+1)+":");
int p=Integer.parseInt(c.readLine());
a[i]=p;
}
for(int i=0;i<5;i++)
{
int s=a[i]*a[i+5];
System.out.print("\nMultiplication of no "+(i+1)+" and no "+(i+6)+" is :"+s);
}
}
catch(IOException e)
{}
}
public static void main(String arg[])throws IOException{
mul shan=new mul();
shan.mul1();
}}
there was some posting problem..
Check this is the FINAL one..
import java.io.*;
class mul{
int[] a=new int[400];
mul()
{}
void mul1()
{
try{
DataInputStream c=new DataInputStream(System.in);
System.out.print(“Enter 1st 200 numbers..\n”);
for(int i=0;i<200;i++)
{
System.out.print("\nEnter no "+(i+1)+":");
int p=Integer.parseInt(c.readLine());
a[i]=p;
}
System.out.print("\n\nEnter Next 200 numbers..\n");
for(int i=200;i<400;i++)
{
System.out.print("\nEnter no "+(i+1)+":");
int p=Integer.parseInt(c.readLine());
a[i]=p;
}
for(int i=0;i<200;i++)
{
int s=a[i]*a[i+200];
System.out.print("\nMultiplication of no "+(i+1)+" and no "+(i+201)+" is :"+s);
}
}
catch(IOException e)
{}
}
public static void main(String arg[]) throws IOException{
mul shan=new mul();
shan.mul1();
}}
when i declare class level variable
in class hello
final static int h=1;
after that one main class created,(test)
then we call in main
hell0.h;
then hello class loaded or not?????
The Confusing Final and Volatile keyword has been changed in New memory model after JDK1.5 and have been included in Visibilty concept to know more read
/* Check this is the FINAL one….. */
class Circle
{
protected float radius;
public static final float PI=3.14f;
public Circle()
{
radius=0f;
}
public Circle( float radius)
{
this.radius=radius;
}
public void setData(float radius)
{
this.radius=radius;
}
public void showData()
{
System.out.println(“radius is:”+radius);
}
public final float getArea()
{
return PI*(float)Math.pow(radius,2);
}
public static void main(String args[])
{
Circle c1=new Circle();
c1.setData(5f);
c1.showData();
}
System.out.println(“Area is:”+c1.getArea());
}
very use full for programmer
great!!!!!!!!it’s the very useful note for comparison to any other reference books…
Java classes declared as final cannot be extended. Restricting inheritance!
here
what’s mean of “Restrictinginheritance!”
class jlc{
public static void main(String as[]){
final int x=10;
byte b=x; System.out.println(b);
}
}
can any one explain how typecasting is possible and memory representation of final keyword.
Thanks very much Joe for such easy and nice explanation. I have a query though.
Could you explain how to make an object reference constant as well as the object assigned to it immutable? I suppose this is possible but still is a puzzel to me.
Thanks in advance,
Satish