What Is The Impact Of Declaring A Method As Final
Nov 14, 20141 Can method declared as final be overridden and overloading ?
2 if A is static sub class of B. how to access a method in class A ?
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Method Implementation Declaring Exception Other Than That Declared In Interface
Aug 31, 2014The 2 minute drill from page 69 SCJP kathy and bert book, says regarding Interfaces, that - "A legal nonabstract implementing class must not declare any new checked exceptions for an implementation method."
When I try the below given code in eclipse , it does not throw any errors . (Here I have tried to throw NullPointerException from testFunc whereas the interface function throws IllegalStateExc)
package abstracttesting;
public class StaticCheck implements check{
public void testFunc() throws NullPointerException{
// TODO Auto-generated method stub
} public static void main(String[] args) {
// TODO Auto-generated method stub
}
}
interface check{
void testFunc() throws IllegalStateException;
}
Final And Static Method?
Feb 7, 2014My teacher has asked me one question that "What is difference between the final method and static method".
View Replies View RelatedDefine All Local Variables And Method Parameters As Final?
May 16, 2015I am using findbugs and PMD as a code analyser. I am keep getting warnings to use local variables and method parameters as final.
I want to know if its a good practice to keep them final or what to do?
Sometime i have a private method which is 1 line longer. Sometime it is annoying to use final.
Swing/AWT/SWT :: Non-final Variable Inside Inner Class Defined In Different Method
Aug 9, 2014this code won't compile because selected row must be declared as final because of it being defined outside the window listener. Is their anyway around this? If I make it final the first time that the variable is called it keeps it starting value until the GUI is closed.
butEdit.addActionListener (new ActionListener () {
@Override
public void actionPerformed (java.awt.event.ActionEvent evt) {
int selectedRow = table.getSelectedRow ();
final String [] values = custTableModel.getRowValues (selectedRow);
[code]....
Program That Implement Final Method And Perform Arithmetic Operation
Mar 4, 2014class A
{
public final int Add(int a,int b) {
return a+b;
}
}
class B
{
public static void main (String args[])
{
System.out.println(Model.Add(5,10));
}
}
This is what I have. I'm not sure if this even makes use of a final method. But when I run it I get an error saying cannot find symbol for line 13.
Cannot Refer To Non-final Variable Inside Inner Class Defined In Different Method
Apr 3, 2014Created a java.sql.connection object. Refering those obj inside public void run() { } If i declare as final inside a method, i can't refer those outside method due to scope. Cannot refer to a non-final variable dbConnObj inside an inner class defined in a different method...
View Replies View RelatedCreating Final Arrays With Final Elements
Aug 2, 2013I want to create a final array with final elements
{code}
final int[] array = {0, 1, 2, 3, 4, 5};
{code}
But here only the reference of the array is final , not it's elements ... So how can I do that??
Declaring Object Using Interface Implemented By Its Class Vs Declaring Object Using Class
Apr 8, 2014Suppose you have a generic Dog class of the pet type that implements a DogInterface of the pet type. What is the difference between;
DogInterface<pet> Rex = new Dog<pet>();
and
Dog<pet> Tye = new Dog<pet>();
In what situations might you want to use Rex instead of Tye?
Declaring Variable And Using Getter
Jul 2, 2014I have question on best practice on declaring variable and using getter. Is there any performance issue if I used getter every time to access the properties values or Is better to use getter once, store in variable then use that variable whenever needed.
a) What is the best practice?
b) Also what if getter in deep level e.g. myTopObj.getInnerOne().getInnerTwo().getProp();
Option 1
Java Code:
var myProp = obj.getProp();
x = myProp;
y = myProp mh_sh_highlight_all('java');
Option 2
Java Code: x = obj.getProp();
y = obj.getProp(); mh_sh_highlight_all('java');
Declaring Variables In GUIs
Aug 25, 2014In most of the GUI examples, it declares the variables right at the start as private.
public class KiloConverterWindow extends JFrame
{
private JPanel panel;
private JLabel messageLabel;
private JTextField kiloTextField;
private JButton calcButton;
private final int WINDOW_WIDTH = 310;
private final int WINDOW_HEIGHT = 100;
In one example though, it declares and creates the different objects in the constructor.
public BorderWindow()
{
setTitle("Border Layout");
setSize(WINDOW_WIDTH, WINDOW_HEIGHT);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setLayout(new BorderLayout());
JButton button1 = new JButton("North Button");
JButton button2 = new JButton("South Button");
JButton button3 = new JButton("East Button");
JButton button4 = new JButton("West Button");
JButton button5 = new JButton("Center Button");
Now what I assume, is that for the second example snippet, because it's sole purpose is to show you the Border layout, there are no events tied to any buttons, and there is no data, other than the names of the buttons. With the first snippet, it's purpose was to show the kilometer to miles converter using a GUI. The purpose of making it private is to prevent the data from being altered from outside code. If I have the right idea, I feel like they should have continued to keep their examples consistent.
Declaring Parameters - Use Void For
Mar 1, 2015I want to have parameters that I use the "void" for, in other words it doesn't return anything.
class code
{
void go()
{
int TestStuff t = new TestStuff();
t.takeTwo(12,34)
}
void takeTwo (int x, int y) {
int z = x + y;
System.out.println("Total is:" + z);
}
}
Table Booking In Restaurant - Declaring 2D Array
Oct 29, 2014import java.io.*;
public class Booking {
private Customer[] [] booking = new Customer [7] [tables];
private int count = tables;
private String restaurant;
[Code] ......
Declaring Static Int - Illegal Modifier For Parameter
Feb 15, 2014I accidentally wrote a code differently than what I should've, and I got these errors :
"Illegal modifier for parameter a; only final is permitted"
"Illegal modifier for parameter b; only final is permitted"
"Illegal modifier for parameter c; only final is permitted"
The code that I wrote and gave these errors:
Java Code:
class Math {
public static void main(String[] args) {
static int a = 11;
static int b = 35;
static int c = 29;
//the rest of the code below
[Code] ....
I noticed that I can declare "static int" only under "class Math" and not under "public static void main".(I had to remove "static" if declaring int under "public static void main");
Declaring Enums - Could Not Find Or Load Main Class
Feb 25, 2014I've just started, so right now I'm reading about declaring enums, the book lists the following code
enum CoffeeSize {
//8,10 & 16 are passed to the constuctor
BIG(6), HUGE(10), OVERWHELMING(16);
CoffeeSize(int ounces){ //constructor
this.ounces = ounces;
[Code] .....
I'm assuming that code to be in a same file since enums can be declared within and outside a class, so I saved it into a file named "Coffee.java", it compiles just fine from command line but when I try to execute "java Coffee" it throws "Error: Could not find or load main class Coffee"...
Declaring Parameters (fields As Protected String) In Java Class
May 19, 2014I am trying to declare fields as protected String custom.field.1096; in my java class but it does not allow me. Can I not declare the field as above? Is there any workaround to achieve this?
View Replies View RelatedWhy Constructor Cannot Be Final
Oct 27, 2014"A constructor cannot be abstract, static, final, native, or synchronized."
I understand on why it can't be all of the above, except "final".
Why can't we have a final constructor, i understand constructors are not inherited, hence no chance/case of overriding etc. But why is it not allowed at all ?
What Handling Exception And Declaring Same Exception In Throws Clause Achieve
Jan 24, 2014I was giving a quick skim to some tutorials on the internet where I have found the exception that is handled is also declared in the throws clause of the method wrapping the try-catch block. For a code representation consider the following:
public void methodName() throws IOException {
try {
...
} catch (IOException ex) {
.... TODO handle exception
}
}
Declaring Class In Main Class - Constructor Cannot Applied To Given Types
Aug 1, 2014So i declared a class in main class but it seems there's error when i compile:
constructor xx in class xx cannot applied to given types
This is my java class:
public class trainer extends person{
String classType;
public trainer(String name, String gender, String address, int id, String classType) {
super(name,gender,address,id);
this.classType=classType;
[Code] ....
And this is the way i declared in main class:
trainer tr = new trainer();
And what i want to do is:
tr.toString();
Why Are Final And Abstract Called As Modifiers
Feb 8, 2015I just wanted to know that why are final and abstract called as modifiers ,what is the essence of calling them as modifiers since there are two types of modifiers access modifiers and non-access modifiers so final and abstract come under the second category ,so why are these called as modifiers?
View Replies View RelatedFinal Reference Variables In Java
Feb 28, 2015I am unable to understand the meaning of this sentence "final reference variables must be initialized before the constructor completes.",What is trying to imply?
View Replies View RelatedWhen Final Variable Occupy Memory
Sep 23, 2014when final variable occupy memory in java?
View Replies View RelatedFinal Static Variables In GregorianCalendar
Oct 27, 2014why using the get method(c.get(c.HOUR_OF_DAY)); gives me the correct hour(currently 19) but directly accesing c.HOUR_OF_DAY returns 11 ? It shows In the documentation that HOUR_OF_DAY is public.
import java.util.*;
public class calendar2 {
public static void main(String[] args) {
new calendar2().timer();
}
private void timer() {
Calendar c=Calendar.getInstance();
//c.clear();
System.out.println(c.get(c.HOUR_OF_DAY));
System.out.println(c.HOUR_OF_DAY);
}
}
How To Take Runtime Value For Static Final Variable
Jul 28, 2014How can i take run time value for static final variable...my lecturer said first time assignment is possible for declared final variable but in my case it shows compile time error..I'm placing my program below with error message
class Sample
{
static final String cname;
void print() {
System.out.println(cname);
}
public static void main(String args[])
{
cname=args[0];
Sample s=new Sample();
s.print();
}
}
Sample.java:11: cannot assign a value to final variable cname.
cname=args[0];
Grade Input And Final Average
Sep 15, 2014For this assignment you will be writing a grade book program. The program will work for one student. It will need to take as input the students name. The user will then be asked to input grades into three categories in this order:
1) homework;
2) quizzes;
3) tests.
The grades in a given category will be averaged to one number that is the average of all grades in that category. The final average will be the weighted average of each category, where homework is worth 25% quizzes are worth 25%, and test are worth 50%. Like this:
Homework Grades: 65, 70, 75, 80, 80 Homework Average: 74
Quiz Grades: 75, 80, 85, 80. Quiz Average: 80
Test Grades: 75, 80, 85, 75 Test Average: 78.75
Final Average = 0.25*HomeworkAvg + 0.25*QuizAvg + 0.50*TestAvg = 77.87
But i only have the average and i dont know how to move past that..
Heres my average code :
import java.util.Scanner;
public class Homework3 {
public static void main(String[] args) {
Scanner myScanner = new Scanner(System.in);
int gradeCount = 0;
int grades = 0;
int holder = 0;
[Code] .....
Parsing Error With Final Bracket
May 8, 2014Im working on a class to add to my final project but im getting a parsing error for the final bracket, i double checked to make sure im not missing any but im still getting an error
import java.util.Scanner;
public class totalprice
{
public static void main(String[] args)
{
scanner keyboard = new Scanner(System.in);
{
DecimalFormat num = new DecimalFormat("#.00");
char meal;
int ammount;
double cost;
[code]....