For the question below, assume the following implementation of an Employee class: 1 class Employee { String name; public Employee (String name) { this.name = name; } public void setName(String name) { this.name = name; The code below is throwing a Null Pointer Exception. The code should create an array of 5 Employees and set the one at index 0 to be named "Mark". Figure out what is going wrong in this code and fix it. Think about how you would explain it if someone came to you with this problem. Your Answer: Feedback public Employee [] createEmployeeList() { Employee [] listOfEmployees = new Employee [5]; listof Employees [0].setName ("Mark"); return listOfEmployees; Result Behavior - tests to ensure employee at index 0 is set corre NullPointerException

For the question below, assume the following implementation of an Employee class: 1 class Employee { String name; public Employee (String name) { this.name = name; } public void setName(String name) { this.name = name; The code below is throwing a Null Pointer Exception. The code should create an array of 5 Employees and set the one at index 0 to be named "Mark". Figure out what is going wrong in this code and fix it. Think about how you would explain it if someone came to you with this problem. Your Answer: Feedback public Employee [] createEmployeeList() { Employee [] listOfEmployees = new Employee [5]; listof Employees [0].setName ("Mark"); return listOfEmployees; Result Behavior - tests to ensure employee at index 0 is set corre NullPointerException

Database System Concepts

7th Edition

ISBN:9780078022159

Author:Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan

Publisher:Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan

Chapter1: Introduction

Section: Chapter Questions

Problem 1PE

See similar textbooks

Similar questions

A) Consider the generic print() method, write a method that takes an array of E, where E must be Comparable or extend a type that is Comparable, and returns a reference to the greatest object in the array. In this case, the greatest value is one for which compareTo() would return 0 or more for any other object in the array. If there is more than one possible largest value (these would have to be equal to each other but greater than any other objects in the array), it does not matter which one you choose. B) Write a generic Java queue class (a plain queue, not a priority queue). Call it GenericQueue, because the JDK already has an interface called Queue. The class must be able to create a queue of objects of any reference type. Consider the GenericStack class shown in the lecture notes for some hints. Like the Stack, the GenericQueue should use an underlying ArrayList<E>. Write these methods and any others you find useful: enqueue() adds an E to the queue peek() returns a…
TODO 1 Obtain all the indexes with labels equal 2 with np.where and the label array y. Keep the results in two_class_idx also index np.where() at 0 # TODO 1.1 two_class_idx = print(f"two_class_idx output: \n {two_class_idx}") try: print(f"two_class_idx shape: {two_class_idx.shape}") except Exception: pass todo_check([ (isinstance(two_class_idx, np.ndarray),f'two_class_idx is not an NumPy array! two_class_idx is currently a {type(two_class_idx)}'), (np.all(two_class_idx == np.array([3,9,11,12,16])),'two_class_idx does not contain the correct location values') ])
Modify the above code to use the alternative method for multithreading (i.e., implementing the Runnable interface). Name your main class RunnableHelloBye and your subsidiary classes Hello and Goodbye respectively. The fi rst should display the message ‘Hello!’ ten times (with a random delay of 0–2 s between consecutive displays), while the second should do the same with the message ‘Goodbye!’. Note that it will NOT be the main class that implements the Runnable interface, but each of the two subsidiary classes.
Reuse your Car class . In a main, build an object of that class, and print out the object using System.out.println(). Notice that this simply reports the memory address of the object in question, and we’d like to do something more useful. To replace (or override) the toString (or equals) function. Now, build a toString function that prints out the make, model, and odometer reading for a vehicle object. public class Car { //instance variables private int odometer; private String make; private String model; //overloading //constructors public Car(int odometer,String make, String model) { this.odometer = odometer; this.make = make; this.model = model; } public Car(String make, String model) { this.make = make; this.model = model; } public Car(String make) { this.make = make; } /* *getter & setter methods */ public int getOdometer() { return odometer; } public void…
Modify WorkerTester class in such a way it reads from a file (workers.txt) the workers information andstores it in a polymorphic array called workers(of type Worker). The array is then passed to a method calledstatistics() to display the basic information and the received pay for all Salaried paid workers, the less paidworker and the most paid worker.Assume that each line in the workers.txt contains information about one workerIf the worker is a salaried worker, the line contains S name salaryIf the worker is hourly paid, the line contains H name hourlyRate numHours
PLease use java In this assignment, you will implement a class called ArrayAndArrayList. This class includessome interesting methods for working with Arrays and ArrayLists.For example, the ArrayAndArrayList class has a “findMax” method which finds and returns themax number in a given array. For a defined array: int[] array = {1, 3, 5, 7, 9}, callingfindMax(array) will return 9.There are 4 methods that need to be implemented in the ArrayAndArrayList class:● howMany(int[] array, int element) - Counts the number of occurrences of the givenelement in the given array.● findMax(int[] array) - Finds the max number in the given array.● maxArray(int[] array) - Keeps track of every occurrence of the max number in the givenarray.● swapZero(int[] array) - Puts all of the zeros in the given array, at the end of the givenarray.Each method has been defined for you, but without the code. See the javadoc for each methodfor instructions on what the method is supposed to do and how to write the code. It…
Design a generic method 'sum' that accepts an array of any type such as int, double or float and this method will return the sum of all elements in the array. Create a test class and call 'sum twice by passing arrays of different types.
Write a program Reverse.java that prompts the user to enter ten numbers, reverses an arrayby copying it to a new array and displays the numbers. The array is an attribute of the mainclass.
Declare and implement 5 classes: FloatArray, SortedArray, FrontArray, PositiveArray & NegativeArray 1- The FloatArray class stores a dynamic array of floats and its size. It has:- A parameterized constructor that takes the array size. - An add method that adds a float at the end of the array.- Overloading for the insertion operator << to write the array to afile (ofstream)- Overloading for the extraction operator >> to read the array elements from the file (ifstream) and add them to the array.- A destructor to deallocate the array 2- The SortedArray inherits from FloatArray. It has:- A parameterized constructor that takes the array size. - An add method that adds a float at the right place in the arraysuch that the array remains sorted with every add. Don’t add to the array then sort but rather add in the right place. 3- The FrontArray inherits from FloatArray. It has:- A parameterized constructor that takes the array size. - An add method that adds a float at the front…
Declare and implement 5 classes: FloatArray, SortedArray, FrontArray, PositiveArray & NegativeArray. 1- The FloatArray class stores a dynamic array of floats and its size. It has:- A parameterized constructor that takes the array size. - An add method that adds a float at the end of the array.- Overloading for the insertion operator << to write the array to afile (ofstream)- Overloading for the extraction operator >> to read the array elements from the file (ifstream) and add them to the array.- A destructor to deallocate the array2- The SortedArray inherits from FloatArray. It has:- A parameterized constructor that takes the array size. - An add method that adds a float at the right place in the arraysuch that the array remains sorted with every add. Don’t add to the array then sort but rather add in the right place.3- The FrontArray inherits from FloatArray. It has:- A parameterized constructor that takes the array size. - An add method that adds a float at the front…
Task Declare and implement 5 classes: FloatArray, SortedArray, FrontArray, PositiveArray & NegativeArray. 1- The FloatArray class stores a dynamic array of floats and its size. It has: - A parameterized constructor that takes the array size. - An add method that adds a float at the end of the array. - Overloading for the insertion operator << to write the array to a file (ofstream) - Overloading for the extraction operator >> to read the array elements from the file (ifstream) and add them to the array. - A destructor to deallocate the array 2- The SortedArray inherits from FloatArray. It has: - A parameterized constructor that takes the array size. - An add method that adds a float at the right place in the array such that the array remains sorted with every add. Don’t add to the array then sort but rather add in the right place. 3- The FrontArray inherits from FloatArray. It has: - A parameterized constructor that takes the array size. - An add method that…
Write a JAVA program Write a function inside ProblemSolution class whose return type is void, accepts an array and the length of the array as input parameters. The function should call a static method display of MyArray class by passing an array and length value. Input 5 1 5 8 2 0 Where, First line of input represents the size of an array. Second line represents array elements. Output 1 5 8 2 0 Assume that, N is an integer within the range [0 to 10000]. Array elements are integers within the range [-2147483648 to 2147483647].