I created a superclass Ships and under that a class CivilShips. Under that HumanBulkFreighter.
I declared variables in Ships and CivilShips and wanted to have them set in HBF to a specific value. When I know try to compile them I get the following:
HumanBulkFreighter.java:2: error: <identifier> expected
cargo=1500;
^
HumanBulkFreighter.java:3: error: <identifier> expected
size=200;
[Code] ....
When do you get the error <identifier> expected? I've written a small application where input is accepted by a textfield and based on some condition a dialog should be displayed saying "invalid i/p". But am not able to correct ths particular error ....
View Replies View RelatedI'm getting an "identifier expected" error for the following code for comparing 2 wallets and printing each pair of banknotes. Here's the code.
public void printBankNotePairs(Wallet other)
{
StringBuffer myBuffer = new StringBuffer("Pairs: ");
for(int i = 0; i < count; i++)
{
for(int j = 0 + i; j < other.length; j++)
[Code] .....
my code keeps saying identifier expected Here's my code
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.border.*;
import java.awt.BorderLayout;
import javax.swing.JFrame;
import javax.swing.JButton;
import javax.swing.JLabel;
import java.awt.event.ActionListener;
import java.awt.event.ActionEvent;
[code]....
I'm working through Head First Java, and I'm struggling with the chapter 6 magnet exercise on page 161. I've checked my answer countless times, and it appears to match the book's code, but when I try to run it on my computer I'm getting an error. It says:
error: <identifier> expected
System.out.println^(" "); and
error: illegal start of type
System.out.println(^" ");, both for line 32.
I cannot seem to figure out what is different about my code!!
import java.util.*;
public class ArrayListMagnet {
public static void main (String [] args) {
ArrayList<String> a = new ArrayList<String>();
a.add (0, "zero");
a.add(1, "one");
a.add(2, "two");
a.add(3, "three");
[Code] .....
Also, I'm not sure if this has anything to do with the above errors, but I'm getting a third error message for line 34 saying:
error: class, interface, or enum expected
}^.
import java.io.*;
class addition {
public static void main(String[] args) {
int num1,num2,sum;
try {
DataInputStream x=new DatainputStream(system.in);
[Code] ,,,,,
//constructor
class Base
{
Base(int a) {
System.out.println("in base"+a);;
}
}
class Cons extends Base
[Code] .....
I have a problem with my code. It gives me the error I put as title:
backgroundA.setOnClickListener(new View.OnClickListener(){
public void onClick(View view){
if (j < 2){
int randomInt1 = random1.nextInt(Deck.length());
int drawableIDA = Deck.getResourceId(randomInt1, -1);
[Code] ....
This error is in the first line and I have also one in the last, where eclipse looking for a @ (O.o). Also I will insert the variable choice1.
final Button choice1 = (Button) findViewById(R.id.A);
I have a problem with my code. It gives me the error I put as title:
backgroundA.setOnClickListener(new View.OnClickListener(){
public void onClick(View view){
if (j < 2){
[Code]...
This error is in the first line and I have also one in the last, where eclipse looking for a @ (O.o). Also I will insert the variable choice1.
final Button choice1 = (Button) findViewById(R.id.A);
Need to write two files but getting an expected exception error.
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import java.util.Scanner;
import java.io.FileWriter;
public class TestingPanel extends JPanel
[Code] ....
TestingPanel.java:49: error: unreported exception IOException; must be caught or declared to be thrown
FileWriter outputFileQuestions = new FileWriter("Test.txt");
^
TestingPanel.java:50: error: unreported exception IOException; must be caught or declared to be thrown
FileWriter outputFileAnswers = new FileWriter("Answers.txt");
[Code] ....
So the first thing we did was make a program called memory calculator. now we are supposed to make a sub class that modifies the program to also do exponents and natural logs. Then to make a new class that acts as the driver for what is now called the scientific memory calculator which includes the exponent and log. I have watched this through debug and im a little confused. first off it creates a variable for currentValue in current and in sci which are my instances, which i dont think is what i really want to do, I am unsure how to get the things in the Scientificmemcalc to do stuff without calling them directly. so when i try to do the power feature it does everything correct but it sets the sci current value to the correct answer, and now i cant figure out how to pass it on to the current current value.
This is the memory calculator :
public class MemoryCalculator {
public static void main(String[] args) {
MemoryCalculator current = new MemoryCalculator();//creates an instance
int choice = 0;
do{//main loop
System.out.println("Current value: " + current.getCurrentValue() + "
[Code] .....
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;
in my class i have 6 argument constructor
While reading the design patter book, i got one doubt ,There is a List an interface having sub classes ArrayList, LinkedList etc.,
Q1) My question is Why they declared the List as interface rather than Abstract class?
Q2) i read some site -
List l = new ArrayList(); Why it is GOOD line?
ArrayList l = new ArrayList() ; Why it is BAD line?
Answer required with detailed information for Q1 and Q2.
I am working on a program that simulates a bug moving along a horizontal line, My code works correctly when I test it in it's own class but when I tried testing my constructor and methods in a test class I received an error saying, "package stinkBug does not exist" on lines with my methods. However, stinkbug is not a package.
Java 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.
*/
[code]....
I've 3 classes.
1. Circle
2. GetInputFromUser
3. testCircle
package ABC;
public class Circle {
private double radius;
public double getRadius() {
return radius;
[Code] .....
In the testCircle class, in the line: getRadius = ui1.GetInput();
It's showing the error: The method GetInput(float) in the type GetInputFromUser is not applicable for the arguments ()
And when I do: getRadius = ui1.GetInput(rad);
It's showing the error: rad cannot be resolved
I've created a constructor in bean and put an value to my string after doing so all started to work properly. I am trying to get my application to work but no luck so far. I have looked for similar issues but although there were similar I've got no luck in fixing mine.
When I am trying to put an value in the input file i got error message (/zadanie_1.xhtml @15,75 value="#{z_1.lancuch}": Target Unreachable, identifier 'z_1' resolved to null).
My starting page:
<?xml version='1.0' encoding='UTF-8' ?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml"
xmlns:h="http://xmlns.jcp.org/jsf/html">
[Code]......
I am trying to implement the JSF 2.0 project with Primefaces from one of the tutorial, i con login with only jsf but not when i use primeface where i am getting following error.
Error Log
HTTP Status 500 - /login2.xhtml @23,98 value="#{employee.userName}": Target Unreachable, identifier 'employee' resolved to null type Exception report
message /login2.xhtml @23,98 value="#{employee.userName}": Target Unreachable, identifier 'employee' resolved to null description The server encountered an internal error that prevented it from fulfilling this request.
exception
javax.servlet.ServletException: /login2.xhtml @23,98 value="#{employee.userName}": Target Unreachable, identifier 'employee' resolved to null
javax.faces.webapp.FacesServlet.service(FacesServlet.java:321)
org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)root cause
[Code] ....
Note The full stack trace of the root cause is available in the Apache Tomcat/7.0.57 logs. in Apache Tomcat/7.0.57
Employee.java
package com.login.sample;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import javax.annotation.PostConstruct;
[Code] ....
I am trying to create a login page with a database in which i am getting this error. I am not getting this bean properties.
import java.util.*; //input from library of routines
public class guessingGame
{
public static void main(String[] args)
{
int sN = 7;
int yourGuess;
int guessCount = 0;
[Code] ....
I'm getting an error that says identifier expected and the compiler points to this as the problem:("Pick a number between 1 and 10");
Set<? super TreeMap> s = new HashSet<SortedMap>();
SortedMap<String,String> sm = new TreeMap<String,String>();
TreeMap<String,String> tm = new TreeMap<String,String>();
s.add(sm); //This fails
s.add(tm);
Why does adding sorted map to a Set that allows ? super TreeMap and instantiated as such fail?
Suppose I have
class A {
public void speak() {
System.out.println("I am class A");
}
}
class B extends A{
public void speak() {
System.out.println("I am class B");
}
}
class C extends B{
public void speak() {
System.out.println("I am class C");
}
}
Why this doesn't work while A is a super type of B ?
public static void insertElements(List<? super B> list){
list.add(new A()); //not OK, why?
}
the problem which im facing when executing jar file is it is not working same as when i run file using the IDE.When run jar file, it won't open the new frame even the user and pass combination correct.But when i'm compiling using the IDE, it works as charm. The main menu popped up after i logged in.I've tried Clean and Build and it's not working too.
View Replies View RelatedI want to make an application and must use strategy pattern my idea is to create a super class in this case Movie Player and three sub classer and they'll komminesera with each other using strattegy pattern, one of the sub classes is Button Panel and I want to add it to Movie Player and it was to be its child,so how can I add the butt panel to Movie Player and it shall be its children?
MoviePlayer:
import java.awt.BorderLayout;
import java.awt.Component;
import java.awt.FlowLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
import com.github.sarxos.webcam.WebcamPanel;
[code]....
what does super(); do in the following method, I understand its uses to access variables belonging to the superclass but i am unsure of what that one line does. Here is a sample constructor..
public CreditCard()
{
// fill in the default constructor and use the super call
super();
id = "000000";
year = 0;
}
The super keyword when used explicitly in a subclass constructor must be the first statement but what about if i have a this(parameters) statements ? As the this one must also be the first statement... Does this means that i can have only one or the other ? What about when the super constructor is not explicit (aka implicit ) , can i use the this( parameters) in the same constructor ?
View Replies View RelatedIts written that every constructor calls its super class constructor. And we know, constructors are called to create an object. Does it mean that if I am creating an object of a class, I am actually creating objects of all its super class???
View Replies View RelatedI am creating a set of 3 subclasses, 1 superclass, and an application. In my instructions it says to make set methods in my super and subclass by using dialog boxes. In the application you have 3 different arrays where you create objects and are supposed to call the methods from the subclasses to be used in the application. I don't know how to make the dialog boxes from my subclasses to show up in my application.
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