Interface Class And Object Class Is Compiling Symbol Errors
Nov 16, 2014
I am a beginner here at JAVA and I am trying to program a Gratuity Calculator using both interface class and object class but it keeps on compiling with errors saying "cannot find symbol".I tried everything to fix it but it just keeps on stating symbol.
[CODE]
public class GratuityCalculator extends JFrame
{
/* declarations */
// color objects
Color black = new Color(0, 0, 0);
Color white = new Color(255, 255, 255);
Color light_gray = new Color(192, 192, 192);
I'm trying to make an array of objects, which I then initialize using objects that I have already created. I have main class, a secondary "Other" class, and a third "Other2" class. In the first Other class, I create three objects of the Other2 class, an object array of the type Other2 , and I then try to add the three objects to the object array, which results in the errors:cannot find symbol: class objectArray, ] expected, identifier expected
here is my code:
Other class public class Other { Other2 object1 = new Other2(); Other2 object2 = new Other2(); Other2 object3 = new Other2();
I am currently trying to use Junit to test a whole bunch of stuff. I almost have full line coverage but I am getting hung up on testing an if statement that consists of whether or not an object is an instance of another class. This class happens to be an interface, and even the object is an interface. Weird I know but I just want to know how to get into that if statement. I realize testing interfaces might be a waste of time but I still really want to know how. Here is an example of what I am trying to test:
Java Code:
if(x instance of y){ //where x and y are both interface objects doSomething(); } mh_sh_highlight_all('java');
why interfaces inherit prototype of all the non final methods of the object class in itself? Object class is parent class of all the class and Interface is not the class.
Assuming that we have two classes B and C which inherit from class A. What is the best way to pass a parameter from an object of class B to an object of class C by the use of class A without using static variable and without defining a get function in B?
public test5 { public boolean test(int grille[][]){ for (int i = 0 || i < grille.length || i++){ int max = grille[i][0]; for (int e = 1 || e < grille[i].length || j++){ if (grille[i][e]== max && max !=0){ solution = false; System.exit(1);
I get quite a few errors while trying to compile the BeerSong from the Head First Java book. I copied the text from another person that did the beer song on this forum and it worked as expected. What I can't figure out is why mine is not working when it looks like the text is exactly the same between the two versions. His works, but mine doesn't.
Here is the text and errors that I get:
public class BeerSong { public static void main (String[] args) { int beerNum = 99; String word = "bottles";
I made a software using Netbeans and javaswing. Accidently i deleted my main file which contains my main class and main method. Just to test, i tried to compile and run and it worked but the style of my buttons and windows has changed. So, what happened? How can i change the style of my programs?
//File Accidently deleted package time; public class Time { public static void main( String[] args ) { Window wdow = new Window(); wdow.setVisible( true ); } }
I am watching BrandonioProductions on youtube. His videos are pretty good, but he doesn't seem to get errors where I get them. Here is an example.
public class compareUnequal { public static void main(String[] args){ compareTwo(); } public static void compareTwo(){ String x = "david"; String y = "Notdavid"; if (!x.equals(y)){ System.out.println("Not equal"); } } }
It runs ok, but asked me to proceed when there is an error, but I can`t figure out where the error is!
I want to know is there any way we can call parent class method using child class object without using super keyword in class B in the following program like we can do in c++ by using scoop resolution operator
class A{ public void hello(){ System.out.println("hello"); } } class B extends A{ public void hello(){ //super.hello(); System.out.println("hello1");
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.
import java.util.*; public class CQ1v1{ public static void main(String args []) { Scanner in = new Scanner (System.in) ; String name = ""; System.out.println("Welcome to the Interrogator") ;
[Code] ....
When I compile getting
CQ1v1.java:12: error: cannot find symbol x = in.nextLine (); ^ symbol: variable x location: class CQ1v1 CQ1v1.java:21: error: cannot find symbol
I have this ListInterface class that has operations for my linked list and a LList class. The Llist and ListInterface classes are perfect. My job is to create a driver, or a demo class that showcases these operations. That being said, heres the driver so far:
import java.util.*; public abstract class DriverWilson implements ListInterface { public static void main(String[] args) {
Design a class named Person and its two subclasses named Student and Employee. Make Faculty and Staff subclasses of Employee. There is also a MyDate class as explained below. A person has a name, address, phone number, and email address. A student has a status (freshman, sophomore, junior, or senior). Define the status as an integer which can have the value 0 (for "Freshman"),
1 (for "Sophomore"), 2 (for "Junior"), and 3 (for "Senior"),
but don't allow the status to be set to any other values. An employee has an office, salary, and dateHired. The dateHired is a MyDate field, which contains the fields: year, month, and day. The MyDate class does not explicitly inherit from any class, and it should have a no-arg constructor that sets the year, month, and day to the current year, month, and day. The MyDate class should also have a three-argument constructor that gets three int arguments for the year, month and day to set the year, month and day.
A faculty member has office hours and a rank. Define the rank as a String (for values like "Professor" or "Instructor"). A staff member has a title, which is also a String. Use data types for the fields as specified, or where one is not specified, use a data type that is appropriate for the particular field. Write a test program called TestEveryone.java that creates a Person, Student, Employee, Faculty, and Staff object, and invoke their toString() method (you don't need to call the objects' toString() method explicitly).
Note: Your MyDate.java class is the object class that your dateHired field is created from in the Employee.java class.
Do not use the Person, Employee or Faculty classes defined on pages 383 and 384 of the book. Create new ones.Here is the code I have so far concerning the employee and MyDate.
public class Employee extends Person { private String office; private double salary; //private MyDate dateHired; //7 argument constructor for employee public Employee(String name, String phoneNumber, String email, String address, String office, double salary /*MyDate dateHired*/) { super(name, phoneNumber, email, address);
In the process of creating a new class, I need to move my main method from the class SaveDate to the class DynamicTest. Below I have listed the code of both classes.The objective is to be able to run my program from the DynamicTest Class. I need understanding the process of moving my main method to a different class and creating an Object of a class and calling its method.
public class SaveData { private static final Map<String, Object> myCachedTreeMap = new TreeMap<String, Object>(); public static final List<String> getLines(final String resourceParam, final Charset charset) throws IOException{ System.out.println("Please get: "+resourceParam); if (myCachedTreeMap.containsKey(resourceParam) ) { // Use the cached file, to prevent an additional read.
public class Person { protected static int MAX_AGE = 150; protected static int MIN_AGE = 0; private static final String VALID_WORD_REGEXP = "[a-zA-Z]{3,30}"; private String firstName; private String lastName;
[Code] ....
I'm trying to learn right way how to throw exceptions. I
Besides that I have couple questions:
I can't quite understand throws statement. I'm thinking throws statement is for passing exceptions one level higher(with are not cought in this caller function). So that would mean I need to put throws in this function only:
Java Code: Person(String firstName, String lastName, int age) mh_sh_highlight_all('java');
Am I right or wrong and is there any other use for it? If so that would mean when
Java Code: Person person = new Person(.....) mh_sh_highlight_all('java');
I have the following code snipet and I get the following errors
interface expected here [javac] private class fileFilter implements FileNameExtensionFilter{ [javac] ^ cannot find symbol [javac] symbol : method fileFilter(java.lang.Object) [javac] location: class gui.components.StartupDialog
import javax.swing.*; public class opt { public int code[]; public static void main(String[] args) { int xxx = 1;
[Code] ....
Where did I did wrong cus I keep getting these errors: What do I need to do to fix the errors?
F:>javac opt.java opt.java:25: error: cannot find symbol cd.checkDeclare<zz>; ^ symbol: method checkDeclare<String> location: variable cd of type code[] java:32: error: cannot find symbol
I created a Test main method to test my Inventory and InventoryItem class to see if they are functioning properly. I am currently trying to read a text .dat file, but I keep getting "...cannot find symbol" for descripIn when I try to compile it.
"You might wonder what happens when a static synchronized method is invoked, since a static method is associated with a class, not an object. In this case, the thread acquires the intrinsic lock for the Class object associated with the class. "What is a Class object associated with a class. Google search rather finds material about the Object class.
Here is my code that is supposed to read a user-selected document, create text boxes from that info, and display them. (There is a lot of code in there that may not be relevent, but just ignore that.) When I compile, I receive errors that it can not find the symbols color, xIn, yIn, w, and h.
Here's my code:
import javax.swing.*; import javax.swing.event.*; import java.awt.*; import java.awt.event.*; import java.util.*; import java.io.*; public class Ex22 extends Basic {
I know whats the interfaces and abstract class and also know that difference between interface and abstract class,but here my doubt is eventhough abstract class more advantage than the interface,then why should we use interfaces and when?
