public Polygon polygonFrom(Point[] corners) {
// method body goes here
}
So from what I understand this is a constructor method for a Polygon object from the Polygon class. What I dont get is the name of the method polygonFrom()
Shouldn't a constructor for a Polygon just have the same name as the class? Because from earlier examples in the tutorial it seems to me that this is what has been done
For example:
public Bicycle(int startCadence, int startSpeed, int startGear) {
gear = startGear;
cadence = startCadence;
speed = startSpeed;
}
I am trying to figure out how to get information back from a different method.
Basically I want to write a program to create a car, but I want to be able to add features based on user our put (V6 versus V8, Color choice, etc), but I want each one to be broken out into their own method but I am unsure of how to call from the main method and return the variable (engineSize = V8, color = blue, etc).
Java SE Runtime Environment build 1.8.0..This is part of the code:
public static int addAddress (String[] number, boolean[] front, double[] total) { int num = 0; double ffee = 0; /*boolean value = false;*/
[code]...
I have tried using the line of code commented out, /*boolean value = false;*/. However, another error is displayed. The compiler shows the following...
Inspection.java:33: error: incompatible types: boolean cannot be converted to boolean[] front[num]= defineFront(num, value); ^ Note: Some messages have been simplified; recompile with -Xdiags:verbose to get full output error...I know that boolean values are by default stored as false, once you create the array. However, I'm having trouble passing the variable to the method.
I am working on an independent project it is a simple little text based rpg that will run in a counsel window. I have an object for Character that is creating during a CreateCharacter method. I want the play to be able to enter a character that will open up a menu that displays things like the name and health and stuff of the character from the object created in CreateCharacter, but because I have it in a different class I don't know how to reference the object made in CreateCharacter.
I have it in 6 files
Character --- Object with getters/setters for things like name, age, race, class, ect MainMenu --- Displays title and promts for new game and quit CreateCharacter --- Walks through and sets all values in Character Stats --- Keeps the players stats (health, attack, ect) in an array Intro --- Beginning demo thing (not really important for this question) Menu --- Displays all current user stats (Having issues with this one)
I got the correct output here. But now I want to generalize my method into a utility class so that I can reuse the same method for setting response data directly to respective beans as given below:-
My question is how will I pass the bean object in my utility class?
public static Object getResponseData(String response,[b]String bean[/b]) throws Exception { ObjectMapper mapper = new ObjectMapper(); mapper.configure(DeserializationConfig.Feature.FAIL_ON_UNKNOWN_PROPERTIES, false); JsonNode root = mapper.readTree(response);
I am having an issue with a small part of my project. i am supposed to make a hash table with a file containing words. The file is being passed into my constructor, where i basically just all it "filename" of type string. Im supposed to get the contents of the file and put it into the table. the problem I'm having is making the connection between my constructor and a method called "start" which basically does all the work. Im not sure how to go by doing this, how could i use the variable "filename" from my constructer in my start method?:
import java.io.*; import java.util.*; public class WordCount { //private fields, including your HashMap variable HashMap<String,Object> hmap =new HashMap<String,Object>();//(table size,load factor) public WordCount( String infileName){ String filename =infileName;
So I want to know how in Java you can pass a unkown type into a method (type can be an int, double, or a user defined object) and return that unkown type.
example of what I want: Java Code: public (unknowntype)[] method2 ((unknowntype)[]) //Process Data //unknowntype.process(); return (unknowntype); } mh_sh_highlight_all('java');
I know in C you can use void pointers and in c++ we have templates but I do not know how java handles this. Also I want to know if it is possible to call a method in the unknowntype.
So, this is weird for me because I don't really understand why the BorderLayout class constructor is being initialized as a parameter for the setLayout..
I just kinda get stuck when it comes to passing values into constructors, using main method or static method functionality. In theory i kind of understand how it work but when i type it, it's totally different! I have to have a junit test too but i guess i could do that in the end.
I have attached the assignment. So, how to proceed with this:
public class Flight { int flight_number, capacity, number_of_seats_left; String origin, destination; String departure_time; double original_price;
This program contains a superclass and a subclass that will gather the following information from the user:
name, address, phone number, and customer number.
Everything works fine except that I have to create a boolean method in this program that is required to determine based on user input whether they want to be added to a mailing list.
I cannot get this method to work with main, each time it is called it will always return the value but main will constantly read the last statement (else, where it will read "not wanting to be added to the mailing list).
The only way I can get this part of the program to work is by adding an equals method in main that ignores the case, but I am required to write a boolean method so this is not allowed.
Superclass:
public class Person { private String name; private String address; private String phoneNum; public Person(String pName, String add, String number) { name = pName; address = add;
currently I am doing my java web application project ,and it has following steps 1) Upload the txt files 2) java servlet gets the txt file's url , read the data and do the calculation 3) pass the results
I almost finished the second step , and working on the first step .Since there are so many input files at a given time , i have to use drag and drop method to get the file's location.how to pass file's path to servlet.( servlet code can read the data from the given txt file path )software used - tomcat and netbeans 8.0
I don't understand, why when in the constructor of the superclass A the method init() is called (line 4), the overridden version of the subclass is invoked (line 26) and not the superclass version (line 7):
class A { public A () { init(); } public void init() { System.out.println("test");
[Code] ....
I would have guessed that above code prints
test 1
But instead you get a NPE (because when the constructor of B is invoked
public static void main(String[] args) { new B(); }
Then there is first the implicit call to super:
public B() { s = " "; init(); }
Which is the constructor of A:
public A () { init(); }
But here now this init() method is not the version of A ( public void init() { System.out.println("test"); }) but the overriden version of the subclass (B): public void init() { System.out.println(s+=s.length()); }...
Which throws an NPE of course, because the initialization of s has not occured yet (it happens only after the implicit call to super() has finished (see public B() { s = " "; init(); }))
1 - I don't understand why I'm getting an empty stack error when calling the removecard method in my Table class line 13?
2 - I am trying to use a constructor to populate my deck of cards instead of a method when creating my theDeck object in my Table class line 11 but I get the following error:
java.lang.StackOverflowError at java.util.Vector.<init>(Unknown Source) at java.util.Vector.<init>(Unknown Source) at java.util.Stack.<init>(Unknown Source) at Deck.<init>(Deck.java:7) at Deck.<init>(Deck.java:34)
I am trying to pass an object of type Product p to my editProduct method, however trying to call p.getName(); doesn't work and throws a NullPointerException. The same kind of thing works for my displayRecord method (in a different class) and I can call .getName() on Product p, also passed as an argument to that method. Below is my editProduct class. The NullPointerExcepion is being thrown at line 61 (i.e., nameField.setText(p.getName());).
I don't know if I explained right, so here's a line thing of how the classes relate:
And as a side note: adding the line p = new Product(); fixes it and successfully runs the class (including the Save and Quit parts) but obviously I want it to specifically refer to the Product I pass to the method.
I'm asking a question because I don't understand how Product p could possibly be null, because the argument is passed through my DisplayRecord class, which also takes a Product p argument and works. In that class, I have declared Product prod = p; and prod is what I am passing to editProduct.
public Unit(String code, String name) { enrolStudent(student); this.unitCode = code; this.unitName = name; } public void enrolStudent(Student newStudent){ students = new ArrayList<Student>(); newStudent = new Student(24662496, "Kingsley", " Iwunze"); students.add(newStudent); }
how can I call this enrolStudent() method on this Unit constructor in another class when I create a new Unit. all I need is to enroll students in units when units are created. below is my create unit method.
