Trying to find a way to use primitive data types to overload sound()method. I can't seem to warp my head around using an int or a double to overload the method. And if I did, how do you call them in the main afterwards?
View RepliesI have an int array that has information read from a file. Now i want to display this int on a jtable but ofcourse i cant display primitive data types.. and also you cannot cast an int[] to an Object[], so I am stuck...
View Replies View RelatedHow I'm supposed to write out the statement.
I am fairly certain that I should be making variable "b" and "c" a float. But beyond that I'm confused.
uploadfromtaptalk1407333378833.jpg
I get an error when I try to divide 500 miles by 25.5 gallons
Exception in thread "main" java.lang.NumberFormatException: For input string: "25.5"
at java.lang.NumberFormatException.forInputString(Num berFormatException.java:65)
at java.lang.Integer.parseInt(Integer.java:580)
at java.lang.Integer.parseInt(Integer.java:615)
at Mileage.main(Mileage.java:42)
Java Result: 1
[Code] .....
Why the following is happening.
For the below code, when I execute it, it prints
Short method 10 //result 1
Sub class short method 10 //result 2
Which is as expected but if I comment out line 3, then it prints
Integer method 10 //result 3
Integer method 10 //result 4
I can understand result 3 is because of an upcast from short to int, since FunWithOverloading will not have a overloaded method with short now. However, what is happening with result 4? Shouldn't it call methodA of the subclass with the argument type short? If its because I have declared the reference variable, derived, of the type FunWithOverloading, then how come the first result correctly picks the overloaded method of the sub class?
class FunWithOverloading{
void methodA(int x){System.out.println("Integer method " + x);}
void methodA(short x){System.out.println("Short method " + x);} //line 3
} class OverloadedSubClass extends FunWithOverloading{
void methodA(short x){System.out.println("Sub class short method " + x);}
[Code] ....
I've got a question to ask.
public class AutoBoxingExample {
public void add(Integer intVal){
System.out.println("Wrapper");
}
public void add(int value){
System.out.println("Primitive");
}
public static void main(String[] args) {
AutoBoxingExample auto = new AutoBoxingExample();
auto.add(12);
}
}
The output is "Wrapper". What would be the reason behind it?
Why is it necessary to implement the comparable interface for primitive types and not for classes such as Integer, String etc . . . ?
View Replies View RelatedI am trying to remove the duplicate elements from ArrayList using .contains() if elements are primitive datatype it works but user-defined datatype does not work.
public class UserBean {
String name;
String address;
public String getName() {
return name;
[code]....
I haven't been able to find a cut and paste working example of how to receive MIDI data from a MIDI device, like my piano, and display something to System.out.There are all sorts of examples for synthesizers, sequencers and sending data to a MIDI device, but I have not been able to find a single example of how to receive MIDI data and just display a simple message.
I just need something simple that works to start playing with it, and understanding how it works. Having a working example would also support understanding the Sound API descriptions. They read like differential equations texts books to me, i.e. not clear at all.
I have a working example of how to poll all devices and getDevice.info, which is supposed to then be used to address a specific MIDI device.
I've also looked at a number of books, in the store and on line.I haven't seen a single example anywhere.the closest I found to working examples was on StackOverflow, but I didn't understand some of the other code in the examples, which may or may not have been working correctly anyway.
I am totally new to Java. What is the purpose of this method?
Flow of the int x=3; like where does the 3 go step by step?
Passing Primitive Data Type Arguments (from oracle java tutorials)
Primitive arguments, such as an int or a double, are passed into methods by value. This means that any changes to the values of the parameters exist only within the scope of the method. When the method returns, the parameters are gone and any changes to them are lost. Here is an example:
public class PassPrimitiveByValue {
public static void main(String[] args) {
int x = 3;
// invoke passMethod() with
// x as argument
passMethod(x);
[Code] ....
I have doubt in generics,
List<int> c=new ArrayList<int>();
why we cannot use primitive data type like int,double.
I have a code in which I am reading input from System.in and Destination is some where else
Here is my code
File file=new File("D:/output.txt");
OutputStream os=new java.io.FileOutputStream(file);
Scanner scanner=new Scanner(System.in);
System.out.println("Enter Data to write on File");
String text=scanner.nextLine();
int c=Integer.parseInt(text);
int a;
while((a=c.read())!=-1)
os.write(a);
System.out.println("File Written is Successful");
In the line while((a=c.read())!=-1)
a compile time error is shown "cannot invoke read on primitive data type int"
Where I am going wrong?
I have declared an array list that will store data type of 1 Character and 2 integer. The data that will be store in this list is
1. A = {0 3}
2. B = {0 5}
3. C = {0 3}
4. D = {0 3}
5. E = {0 5}
6. F = {0 6}
Now here the alphabets are routers and integers are there con1 and con2 respectively. I have a set of router={ A,B,C,D,E,F}.
Step 1:I have to subtract con1 from con2 i.e. (3-0) of all the routers and
Step 2: then put the router having largest value in new set 1 and
Step 3: then this router will be subtract from the router set.
Step 4:then again I have to repeat the step 1 until the value of routers become <= 1.
Now what I did is I defined 3 arrays first is String array that stores names of routers, 2nd array that stores the first value and 3rd array that stores the second value. I can find the largest value but how to store the name of router against the largest value in the set.
I need to write a simple program that displays up to 5 pairings of data types (int, string) (string, long) ect. I need to have at least two classes, a Pair class (generic) and an PairTest class.
View Replies View RelatedI have to read data from a text file and print it in a new text file. An example of one line is like this:
Johnson 85 98 75 89 82
I then have to take the average of all the numbers and assign a "grade" to the numbers for each line of the text file and make a new file so it looks like this for 10 lines:
Name 1 2 3 4 5 Average Grade
Johnson 85 98 75 89 82 85.80 B
My problem is extracting the data from the file so I can use it.
I have seen many ways of describing what objects are, one being that objects are a user-defined datatype. However, if objects are datatypes, then what does that make classes? To me, it seems as though classes should be the "types" of data defined by the programmer, and objects should be the specific "values" of that user defined data type. As an example, an integer would be a class, while 1 would be a "value" of that class, i.e. an object. From this point of view, I don't see why a specific number would be a data type... Therefore, why do we say that objects are user defined data types rather than classes?
View Replies View RelatedI would like to create an ArrayList from data types stored in a text file.The ArrayList would be multidimensional with two data types; int, String.
Example text file could be:
4 cahiers grand format
3 stylots bic bleu
5 gommes
I find it very difficult for multiple data types i don't see how its possible.
I am creating a calculator in which a user will directly input the numbers and the operator...
Here is my code:
int answer = 0;
int num1, num2;
char operator;
System.out.print("Enter calculation: ");
num1 = kb.nextInt();
operator = kb.next().charAt(0);
num2 = kb.nextInt();
The code above will accept the user input when there are spaces like this: 1 + 1
So the program will give an answer which is 2...BUT
if i input 1+1 it will give an error...Exception in thread "main" java.util.InputMismatchException
How can i do that it will separate integer to character? because i set the operator as character....
So that it will accept one digit to several digit numbers... like 500+84 or 1520+872??
I am trying to override the equals method for my class TeamMember I have two fields:
private Details details;
private double salary;
Code for override I get an error on salary saying cannot invoke equals (double) on the primitive type (double)
Is their something I am missing/coding wrong?
Java Code:
public boolean equals(Object obj) {
//test exceptional cases
//avoid potential NullPointerException/ClassCastException
if ((obj == null) || (this.getClass() != obj.getClass()))
return false;
TeamMember other = (TeamMember) obj; //cast to a TeamMember object
// compare fields details and salary
return this.details.equals(other.details)
&& this.salary.equals(other.salary);
} mh_sh_highlight_all('java');
What class does method Planet.values() in the code below belong to? I thought it belongs to java.lang.Enum but when I could not see it in Java API 7.
package enumeration;
public class EnumTest {
public static void main(String[] args) {
//Planet myPlanet = Planet.EARTH;
// Check arguments supplied
if (args.length != 1) {
System.err.println("Usage: java EnumTest <earth_weight>");
System.exit(-1);
[code]....
Here is my code:
import java.util.*;public class DebugSix {
public static void main(String[] args) {
ArrayList<String>products = new ArrayList();
products.add("shampoo");
products.add("moisturizer");
products.add("conditioner");
Collections.sort(products);
[Code] ....
I am using netbeans and getting errors for display(); and size(); it is telling me the errors are :
for the display error, "method display in class DebugSix cannot be applied to given types;
display();" and for the size() is : "cannot find symbol System.out.println("
The size of the list is " + size());"
how many types of inputting method in java?can you explain with examples?
View Replies View RelatedI am stuck on this part of my assignment. When the answer prints out at the end, the calculation of average is incorrect. This is what the assignment wants:
Write two overloaded methods that return the average of an array with the following headers:
public static int average(int[] array)
public static double average(double[] array)
Write a test program that prompts the user to enter ten double values, invokes this method and displays the average value.
public class Week7Arrays2 {
public static int average(int[] array) {
int sum = 0;
int average = 0;
for (int i = 0; i < array.length; i++) {
sum = sum + array[i];
[code]....
/*
* To change this license header, choose License Headers in Project Properties.
* To change this template file, choose Tools | Templates
* and open the template in the editor.
*/
package BaiVeNha;
import java.util.ArrayList;
import java.util.List;
import javax.swing.table.DefaultTableModel;
[Code] ....
I am trying to create a class to read data from the JOptionPane. I am trying to create a general procedure and then be able to overload it using the rest. Basically I just want to call the procedure readString with options and without options while verifying that the user entered the correct information.
Java Code:
public class BankIO {
public static final Object[] mainMenu = {"1. Create Account", "2. Delete Account", "3. Update Account", "4. Display Information", "5. Quit"};
public static final String APPLICATION_NAME = "Banking Pro";
[Code].....
I am getting an error with my code. How to fix it.
import java.util.Scanner;
import java.util.*;
/*
* FileName: Circle.java
*/
public class Circle {
private double PI = 3.14159;
private double radius;
public Circle()
{
radius = 0.0;
[Code] ....
This is the error i am receiving:
Circle.java:78: error: method getRadius in class Circle cannot be applied to given types;
System.out.println("A circle with a radius of " + circle.getRadius() + " will have an area of " + circle.getArea() + " , a diameter of " + circle.getDiameter() + " and a circumference of " + circle.getCircumference());
^
required: double
found: no arguments
reason: actual and formal argument lists differ in length
1 error