Develop Reference

How to create a private array and access it by the main method in java? [closed]

Closed. This question needs details or clarity. It is not currently accepting answers.
Want to improve this question? Add details and clarify the problem by editing this post.
Closed 2 years ago.
Improve this question
I want to create a class outside the public class but in the same file, and in that class I wanna create a private array which can only be accessed by creating object through the previous public class. I also wanna store data to that array through the public class.

I suggest you to start learning java, this will save you from asking this kind of question next time. For the moment you can find how to achieve what you are asking for in the example bellow :
public class Learning {
public static void main(String[] args) {
Course course = new Course();
List<String> materials = new ArrayList<>();
materials.add("java basic courses");
materials.add("OOP courses");
// here we use setters to set course materials and notes
course.setMaterials(materials);
course.setNotes(new int[] {19,20});
System.out.println("Display course materials");
for (String material : course.getMaterials()) {
System.out.println("Material : " + material);
}
System.out.println("Display Notes");
for (int note : course.getNotes()) {
System.out.println("Note : " + note);
}
}
}
class Course {
private List<String> materials;
private int[] notes;
public List<String> getMaterials() {
return materials;
}
public void setMaterials(List<String> materials) {
this.materials = materials;
}
public int[] getNotes() {
return notes;
}
public void setNotes(int[] notes) {
this.notes = notes;
}
}

Creating a class that has integers, getter/setters, with input validation [closed]

Closed. This question needs details or clarity. It is not currently accepting answers.
Want to improve this question? Add details and clarify the problem by editing this post.
Closed 2 years ago.
Improve this question
I am working on this Java program where I am supposed to write a class called kumquat that has an integer age with getter and setters. Additionally, I need to do input validation. I can't figure out what I'm doing wrong. I'm sorry if this is really simple I'm just still really new to this.
public class Person
{
private int age;
public int getAge()
{
return age;
}
public void setAge(int newAge)
{
this.age = newAge;
}
}
and then my main
public class Kumquat
{
public static void main(int[] args)
{
Person myObj = new Person();
myObj.setAge("5");
System.out.println(myObj.getAge());
}
}

Everything is ok in the Person class. Although in your main the method Person::setAge receives an int as parameter and you're trying to pass a String in line myObj.setAge("5");. Try passing an int like myObj.setAge(5); instead.

you should write String instead of int and setAge should not be string
public static void main(String[] args)
{
Person myObj = new Person();
myObj.setAge(5);
System.out.println(myObj.getAge());
}

ArrayList .add method missing [closed]

Closed. This question needs debugging details. It is not currently accepting answers.
Edit the question to include desired behavior, a specific problem or error, and the shortest code necessary to reproduce the problem. This will help others answer the question.
Closed 8 years ago.
Improve this question
Hello I have the following problem: I want to create an arraylist and want to add some items.
But somehow the .add Method is not there.
import java.util.ArrayList;
public class Chairing{
private int numbers;
ArrayList<Chairs>myList = new ArrayList<Chairs>();
myList.add(5,new Chairset("10"));
}
public class Chair{
int price;
String info;
public Chair(int price, Chairset c){
this.price = price;
info = c.getInfo();
}
}
public class Chairset{
String info;
public Chairset(String id){
id = info;
}
}
For some Reasons I can't add something in my new ArrayList. The constructor for Chair needs a price and an object Chairset. Chairset needs an id.

The problem is your classes have no common type, the tightest generic bound the list can have would be Object. Either use a marker interface, or notice the similarity between Chair and Chairset and have one extend the other - giving them a common type.
Also note that the line in your code where you add to the list is not in a legal location - it must be within a method.
Try this:
public class Chairing {
private int numbers;
List<Chairset> myList = new ArrayList<Chairset>();
public void someMethod() {
myList.add(5,new Chairset("10"));
}
}
public class Chair extends Chairset {
int price;
public Chair(int price, Chairset c){
super(c.getInfo());
this.price = price;
}
}
public class Chairset {
String info;
public Chairset(String id){
id = info;
}
}

Create a list by looping throug array list of type with that Java variable [closed]

Closed. This question does not meet Stack Overflow guidelines. It is not currently accepting answers.
Questions asking for code must demonstrate a minimal understanding of the problem being solved. Include attempted solutions, why they didn't work, and the expected results. See also: Stack Overflow question checklist
Closed 9 years ago.
Improve this question
I have array list of type Warehouse. Each Warehouse has a stock amount. The method getStock() returns the stock level.
I have an ArrayList of Warehouse. I want to get the stock of each warehouse in the list and add it to a list.
My code:
import java.util.*;
public class Warehouses {
ArrayList<Warehouse> warehouses = new ArrayList<Warehouse>();
public Warehouses() {
warehouses.add(new Warehouse("W1", 20, "RM13 8BB"));
warehouses.add(new Warehouse("W2", 28, "RM13 8BB"));
warehouses.add(new Warehouse("W3", 17, "RM13 8BB"));
}
public void stockList() {
ArrayList<Integer> stockList = new ArrayList<Integer>();
for(Warehouse warehouse : warehouses) {
Integer stock = warehouse.getStock();
System.out.println(stock);
}
}
}
class Warehouse
{
// instance variables - replace the example below with your own
private String warehouseID;
private int warehouseStock;
private String location;
/**
* Constructor for objects of class Warehouse
*/
public Warehouse(String warehouseID, int warehouseStock, String location)
{
// initialise instance variables
warehouseID = warehouseID;
warehouseStock = warehouseStock;
location = location;
}
public int getStock(){
return warehouseStock;
}
public String getLocation() {
return location;
}
}
When I call stockList() I just get three empty values. What is wrong here?
Thanks

Assign the constructor arguments of Warehouse to the class member variables rather than re-assigning the local variables themselves
public Warehouse(String warehouseID, int warehouseStock, String location) {
this.warehouseID = warehouseID;
this.warehouseStock = warehouseStock;
this.location = location;
}

How to access remote Object [closed]

Closed. This question does not meet Stack Overflow guidelines. It is not currently accepting answers.
Closed 9 years ago.
Questions concerning problems with code you've written must describe the specific problem — and include valid code to reproduce it — in the question itself. See SSCCE.org for guidance.
Questions must demonstrate a minimal understanding of the problem being solved. Tell us what you've tried to do, why it didn't work, and how it should work. See also: Stack Overflow question checklist
Improve this question
I'm new to Java. I want to create Java Object with test data and access the object from remote class. I created this object:
public class TestAgentData
{
public TestAgentDataObj tad;
public class TestAgentDataObj
{
public int agentId = 1234;
public String agentName = "AgentName";
public String description = "AgentDscription";
public TestAgentDataObj(int agentId, String agentName, String description)
{
this.agentId = agentId;
this.agentName = agentName;
this.description = description;
}
public int getAgentId()
{
return agentId;
}
public void setAgentId(int agentId)
{
this.agentId = agentId;
}
public String getAgentName()
{
return agentName;
}
public void setAgentName(String agentName)
{
this.agentName = agentName;
}
public String getDescription()
{
return description;
}
public void setDescription(String description)
{
this.description = description;
}
}
public TestAgentDataObj getTad()
{
return tad;
}
public void setTad(TestAgentDataObj tad)
{
this.tad = tad;
}
}
I tried to access the object from remote class:
Object eded = new TestAgentData.getTad();
But I get error in Netbeans. Can you tell what is the proper way to access data in a Java Object?

I think you need a better understanding about java. There are big errors in this.
You cannot way you create your object is wrong its new TestAgentData()
You can't call getTad() from an object of type Object because there is no getTad() method defined in Object class. Rather do the following
TestAgentDataObj obj=new TestAgentData().new TestAgentDataObj();
TestAgentData eded = new TestAgentData();
eded.setTad(obj);
TestAgentDataObj result=eded.getTad();