Is It Correct To Declare A Class Inside Main Method
Jan 21, 2014
I saw an example where an (inner)class is declared inside the main method, this is correct or not and why/when it's reasonable to use?so smth like this
public class myClass()
{
public static void myMethod(myInnerClass obj)
{
if (obj.method())
I'm trying to code a little text RPG. I've made a little "personality test", with 4 questions (answers a b c), where every letter stands for a type of personality. The analysis of the result is simple counting of the answers, if you have 3 answers a (4 questions), then a has won. If 2 on a, and 2 on b, a simple Random method shows weather result a or b.
Now... the test should give you a "partner" (imagine the pokemon game with 3 different starter pokemon). I have now 3 string variables, like 3 different partners. They are all declared somewhere outside, but i only need one later.
Like...the test is completed, you have your partner and how can i make now that the program is just showing me my partner? Like...when i type " System.out.println(partner); " (outside of the test loop! ) that i only get the one i got through the test?
I was trying to declare in every loop the partner String with every result. But outside the loop java isn't recognising that String, bcs...ofc...it was declared for the loop. So i had in every if or else if clause a " String partner = anwsA;" and answB and answC, thats why i cant declare them outside.
Short: i need a partner String variable that could have 3 possible results... i jut need one
I am just trying to test this array, for a locker combination program that involves classes...but the array is printing out the whacky numbers for the location. When I try to call the method in the main, it does not work. How do I call a method that exist within a class into the main method?
public class locker { public static void main(String[] args) { CombinationLock();
Im writing a simple program to understand classes and objects. Basically what I have is a file called Program.java where I have my main method.I have another file called Person.java which I want to use to create Person objects. That person can have a name, email adress, phone number, etc.I put both these files in the same folder.in Program.java my first statement is:
My problem is that when I compile Program.java i get an error message saying that the package Person.java does not exist.So my question is, when you create a class that you want to use for objects, how do you import that class into your class with the main method so that you can use instances of your other class?
// Add range to Vehicle. class Vehicle { int passengers; // number of passengers int fuelcap; // fuel capacity in gallons int mpg; // fuel consumption in miles per gallon
// Display the range. void range() { System.out.println("Range is " + fuelcap * mpg);
[Code] ....
I'm compiling it in Eclipse and this continues to show in the console display
Minivan can carry 7. Exception in thread "main" java.lang.NoSuchMethodError: Vehicle.range()V at AddMeth.main(AddMeth.java:34)
How do I create an instance of a class in a method?
I am a bit rusty whenever I think of instances. I always think of main method and objects when I see instance which gets me confused on what to do when I am not in a main method. The example:
I have a abstract class, School, and inside School I have some methods that must preform some action on an instance. For example, there is a move() method that must move the instance of School. Another method named, personOld(), which returns whether or not an instance of School surpassed some determined age.
I've written a program just for the sake of it (to learn) and it seem's like theres quite a lot in the main method that perhaps could be split up into seperate classes. I'm not too sure where should start with this though, or what my thought process should have been as I was writing the program.
import java.util.Scanner; public class Loops { public static void main(String[] args) { int answer = 16; Scanner scan = new Scanner(System.in); // Question System.out.println("What is 4 x 4 ?");
[code]...
--- Update ---
here's a version without code comments as they might make it harder to read here -
import java.util.Scanner; public class Loops { public static void main(String[] args) { int answer = 16; Scanner scan = new Scanner(System.in); System.out.println("What is 4 x 4 ?"); int userAnswerInt = 0;
This time I have to make a Black Jack game ( I guess this is a classic) I have created Three classes for this BlackJack( Main), Card, and Player.
What I am trying to do is put the Give one card to the player and remove it from the deck into a separate procedure because I will be doing this several times during the game.
This is the code I have so far Under the class BlackJack.
this 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);
Created 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...
I've been writing classes over and over for school. So I create a class outside of my main class. I create a new constructor and then create objects from my main class. I hope that makes sense. So i use methods in that class to work with the object. So I have an object name I've created <dot> method name. So I can create objects and then use methods from the class, but I'm wondering can I create a method in my main class and use it on that object? I don't understand how to do that.
The following code is located in my main class called InjectionFix. I have another class where I need to call or initiate the string in the code below. How can I achieve this. I tried to create an Object of the class but I cant do this because my other class doesnt contain a main method.How can I get the other class to initiate the code below which is loacted in my main class.
public static String escapeDN(String name) { StringBuilder sb = new StringBuilder(); // space or # character at the beginning of a string if ((name.length() > 0) && ((name.charAt(0) == ' ') || (name.charAt(0) == '#'))) {
I have a quick polymorphism question. I have a parent class and a sub class that extends the parent class. I then declare an array of parent class but instantiate an index to the sub class using polymorphism. Do I have to have all the same methods in the child class that I do in the parent class? Here is an example of what I mean.
public class ParentClass { public ParentClass(....){ } public String doSomething(){ } } public class ChildClass extends ParentClass { public ChildClass(....)
[Code] ....
Is polymorphism similar to interfaces where the child class needs all the same methods?
2. Declare a class called Quadrilateral that can be used to represent a quadrilateral. What instance variables are required? This class should include the following methods:
• Accessor and mutator methods. Notice that negative and zero lengths should not be accepted. • A method called isParallelogram that returns a Boolean value indicating if the quadrilateral is a parallelogram. • A method called isRectangle that indicates if the quadrilateral is a rectangle. This method should invoke the method isParallelogram and return a Boolean value. • A method called isSquare that returns the Boolean value “true” if the quadrilateral is a square. This method should invoke the method isRectangle and return a Boolean value. URL...
import java.awt.Point; public class Quadrilateral{ private Point p1, p2, p3, p4; public Quadrilateral (Point p1, Point p2, Point p3, Point p4) {
I am making an application in java, inside static void main, i want to customize all buttons, text areas and want to put them on desired location inside application. I have tried to use setbounds but can not use it, how can i use it, or is there any other way or layout to make my application components customized layout.
Netbeans tells me it's an illegal start of expression during the initialisation of the interactWithUser method. public class InvertLetter {
/** * @param args the command line arguments */ public static void main(String[] args) { /** * String mit den Kleinbuchstaben. */ final String lowercase = "abcdefghijklmnopqrstuvwxyz";
I need to write a method that will consume string representation of Object type and will return one object of this type. How to set return type for the method in this case?
Here is exmaple :
public <?> identifyType(String typeString){ if (typesString.matches("String")){ return new String(""); }else if (typeString.matches("Integer")){ return new Integer(0); } //....etc..}
How to create object for "class B" and call the "function_B" from other different class D where class D has no connection with class A? Here is my program.
public class A(){ void print(){} } class B{ void function_B(){} } class C{ void function_C(){} }
Here, A, B, C are in the same package. But class D is in different package.
I'd like to know how to return a new array, I wrote in a method below the main method. I want to print the array but system.out.print doesn't work for arrays apparently. What structure i should use?
I have to write a method called censor that gets an array of strings from the user as an argument and then returns an array of strings that contains all of the original strings in the same order except those with length of 4. For example if cat, dog, moose, lazy, with was entered, then it would return the exact same thing except for the words with and lazy.
Currently, my code so far just prints [Ljava.lang.String;@38cfdf and im stuck.
import java.util.Scanner; public class censorProgram { public static void main (String args[]){ Scanner input = new Scanner (System.in); System.out.println ("How many words would you like to enter?"); int lineOfText = input.nextInt();
[Code] ....
I have to make new string array in the method and return words without four letters in the main method
Populate the array with 7 random temperatures from 1 to 100 degrees. (hint use a for loop and a Random number Generator)After the temperatures are in the array, calculate the average of the temperatures in the array.
Print out the average.Print out each temperature in a statement comparing it to the average such as:
The average temperature is 48.94
Temperature 1 is 5.0 and is below average.
Temperature 2 is 67.8 and is above average.
import java.util.Random; public class ArrayOfTemperatures { public static void main(String[] args) { // Declare an array int[] randomtemps = new int[7]; temps[0] = 45;