Does a variable have public access modifier? if we can use it within the class and outside of the class then can i access a public variable as follows??
class mo
{
void display() {
public int a=9;
System.out.println(a);
}
public static void main(String[] args) {
mo m=new mo();
m.display();
}
}
ERROR:
It shows 6 errors :-O.
Error 1. illegal start of the expression
2. class,interface, or enum expected
I'm having difficulty understanding this small piece of code:
package food; public abstract class Fruit { private String color; private String tasteType; public void setColor(String color) { this.color = color; } public abstract void setTasteType(String taste); }
The above is an abstract class which describes the basic structure that every fruit should "extend".
The below is a concrete subclass of the Fruit class called Apple.
import food.Fruit; class Apple extends Fruit { public void setTasteType(String taste) { tasteType = taste; } }
Also do note that the two pieces of code are in different packages!
Upon compiling the Apple class I get the following error: Apple.java:4: error: tasteType has private access in Fruit tasteType = taste; ^
What I don't understand is this: I've given a non-abstract implementation to the "setTasteType" method in the Apple class and clearly setTasteType should have the authority to modify the private instance variables of Fruit. But it turns out I'm wrong.
I will like to add to the questions about constructors and its this. I have a class A with a constructor, i have a class B which initialize the constructor. also i have a class C which needs a variable in class A but doesn't need to initialize the constructor of A. the question how do i access the variable of class A without initializing the constructor.
So far I thought that setting superclass member variables as protected would allow the subclasses to access them using this. and that this was a good approach. However now after further reading am finding that actually these variables are better set as private and then accessed by the subclasses using public method (getters and setters) or constructor.
So my question is do you recommend setting them as private instead of protected and what would be the best way to access these variables from the subclasses ?
how to get access from variables in a super class or a subclass. Here is what I got:
1) I have a super class that is in Jar file, I created a link in Eclipse, I know that the link is created correctly, I am going to concentrate just in one variable, so I don’t have to put all the code here firstName; in the super class(the one that is define in the path)
public class CommissionEmployee { // Field descriptor #6 Ljava/lang/String; private java.lang.String firstName;
I 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?
I am deploy my project in a machine and access it through VPN. In one page i am sending parameters array through hidden input field. When i access it in process page through request.getParameterValues it return null values, you can see it in attachment.This page work fine without VPN.
New to java/programming and i cant understand why the pen variable does not display the the correct value ... For example for input 1 ; 2 ; 3 ; 4 both variables will display 10 and i dont understand why pen does not have the value 6 .
import acm.program.*; public class Chap4_ex12 extends ConsoleProgram { public void run () { int pen = 0; int r = 1; int sum = 0; while (r !=SANTINEL) { r = readInt(" ? "); pen=sum ;
Variables defined in interface are public static and final so I was thinking that we should not be able to override the variables in a class thats implementing the interface. But when I am compiling the below class, it compiles fine and gives the correct values. but when I did disp.abhi = 35; it gives a compile error (cannot override final variable)
interface display{ int abhi = 10; void displayName();
This is my first time working with C++ and I have put together this program and came up with two errors and I am unsure what it is wanting me to do. The errors I got are:
1>c:usersownerdocumentsvisual studio 2010projectsweek5week5passing_by_value.cpp(30): error C2064: term does not evaluate to a function taking 1 arguments 1>c:usersownerdocumentsvisual studio 2010projectsweek5week5passing_by_value.cpp(38): error C2064: term does not evaluate to a function taking 1 arguments
#include<iostream> using std::cin; using std::cout; using std::endl; //initialize arrays int incr10(int* numa,int* numb);
I am new in this programming language, java. I have a problem after I set my path ";C:Program Files (x86)Javajdk1.7.0_51in". I made a simple program but an error occurred. Here's the screenshot.....
I continuously get an error for lines 34, 36, and 37 saying that the variables may not have been initialized.
import java.util.Scanner; import java.util.Random; public class MathTutor { public static void main(String[] args) { Random r = new Random (); Scanner input = new Scanner (System.in); /*int min=1; int max=10;*/ int num1,num2,operation; int n1= r.nextInt((9+1)+1); int n2= r.nextInt((9+1)+1); operation= r.nextInt(3); int correctAnswer; int userAnswer;
How to access session from different context? I have created a session in one jsp, in one context and trying to access it from different context. But, I was unable to access the same. How to achieve it?
I'm using MS Access database. What I want to do, is to get all names of my tables in database.My SQL query :
SELECT TABLE_NAME FROM INFORMATION_SCHEMA.TABLES
is it correct? I found it in one example and didn't change anything.
I could of course execute this and check, but the problem is, that it returns ResultSet(I'm using Java), and I do not know how to manipulate this object in this situation.Cause usually ResultSet contains columns and rows, I think now I should get only bunch of String values.
I am trying to make a program where a ball moves up continuously when you press space, then begins to move down when you reach a certain point. My method for this is to have a timer, and have a method that does this: When you press space, add 10 y coords every second (using a timer), and if you reach 470 y, then begin to drop 10 y coords. I made a method to hold the keylistener, and am running that method inside the actionPerformed method which is within another class. However, since it is a method, I cannot add my keylistener to my frame in the main method.
main error line 9 Java Code: import javax.swing.*; public class Main {
I am trying to prepare for the next installment Java course. I found a syllabus online from last year. All I'm trying to say is that I am not in this course but will be shortly. I tried the first project but I am having subclass issues. I want to access the getStock method in the Executive subclass from the client. I keep getting a cannot find symbol: method getStock from class Employee. I don't know why won't access Executive.
Main:
import java.util.*; public class EmployeeClient extends Employee { public static void main(String[] args) { Scanner input = new Scanner(System.in); //variables String name = " "; int totalSalary = 0; int stock = 0;
I have designed a code that is aimed at simulating a banking environment using access database. However, there are errors and i am not able to create a new account.
import java.awt.*; import java.awt.event.*; import java.awt.FlowLayout; import java.sql.*; import javax.swing.*; public class Bank extends JFrame implements ActionListener
I want to make a database and use it in my java program. I am thinking of using MS Access database, although I m not very sure, sine I will have to use this data later in the SQL database as part of C# program.
How to start to create and use MS database in java program.
I have seen in one tutorial that the steps are:
1. Install your database management system (DBMS) if needed
2.Install a JDBC driver from the vendor of your database
but I am not familiar with this. Any example, or is this above compulsory?