Concept explainers
Create an ArrayList
If you write the last line without a trailing semicolon, you will see the small red object icon. Drag this icon onto the object bench. Examine its methods and try calling some (such as add, remove, size, isEmpty). Also try calling the same methods from the Code Pad. You can access objects on the object bench from the Code Pad by using their names. For example, if you have an ArrayList named all on the object bench, in the Code Pad you can type:
a11.size()
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- Uising the code below. Write a test class called CircleTest that implement below specification: a). The class has an ArrayList that holds objects of type Circle. b). It displays a menu that allows the user to: Enter a Circle (the user only needs to enter the radius). Print all Circles (print the toString for each Circle in the ArrayList). Quit. c). If the user selects option 1, allow the user to input the radius of a circle. Place the circle in the ArrayList in order. You can do this by using loops and the CompareTo method. Do not use methods of ArrayList for this part. Use the compareTo method to insert elements into the array. For example addAt. d) To add a circle Cases: The ArrayList is empty The new circle is less than the first circle, add it at the beginning. The circle is greater than the last circle, add it at the end The new circle belongs somewhere in the middle. e). If the user selects option 2, loop through the ArrayList and print the toString for each member of the…arrow_forwardIf a method given an ArrayList as a parameter calls a second method giving it the same ArrayList, and that second method deletes one of the elements, this will: (produce a non-deterministic result? trigger an error? have an effect? have no effect?) on the first ArrayList. Java uses: (pass by reference? pass by value?) So when an object is passed to a method, what is actually passed is just : (the name of the object? a pointer to the object? the index of the object?) . Select the correct answerarrow_forwardExecute the following statements over initially empty ArrayList myList one after another (cascade). Explain what was changed after each statement (what did it do?) myList.add("z"); ArrayList content: Your explanation (where this output came from): myList.add(0, "a"); ArrayList content: Your explanation (where this output came from): myList.add("t"); ArrayList content: Your explanation (where this output came from): myList.add(2,"w"); ArrayList content: Your explanation (where this output came from): myList.set(0,"b"); ArrayList content: Your explanation (where this output came from):arrow_forward
- Update it to create a class Student that includes four properties: an id (type Integer), a name (type String), a Major (type String) and a Grade (type Double). Use class Student to create objects (using buttonAdd) that will be read from the TextFields then save it into an ArrayList. Perform the following queries on the ArrayList of Student objects and show the results on the listViewStudents (Hint: add buttons as needed): d) Use lambdas and streams to calculate the total average of all Students grades, then show the result. 1. Ch3HW; import javafx.application.Application; import javafx.fxml.FXMLLoader; import javafx.scene.Parent; import javafx.scene.Scene; import javafx.stage.Stage; public class MainApp extends Application{ @Override publicvoidstart(StageprimaryStage) throwsException { FXMLLoader loader =newFXMLLoader(getClass().getResource("StudentScreen.fxml")); Parent parent = loader.load(); Scene scene =newScene(parent);…arrow_forwardGiven a base Plant class and a derived Flower class, complete main() to create an ArrayList called myGarden. The ArrayList should be able to store objects that belong to the Plant class or the Flower class. Create a method called printArrayList(), that uses the printInfo() methods defined in the respective classes and prints each element in myGarden. The program should read plants or flowers from input (ending with -1), add each Plant or Flower to the myGarden ArrayList, and output each element in myGarden using the printInfo() method. Ex. If the input is: plant Spirea 10 flower Hydrangea 30 false lilac flower Rose 6 false white plant Mint 4 -1 the output is: Plant 1 Information: Plant name: Spirea Cost: 10 Plant 2 Information: Plant name: Hydrangea Cost: 30 Annual: false Color of flowers: lilac Plant 3 Information: Plant name: Rose Cost: 6 Annual: false Color of flowers: white Plant 4 Information: Plant name: Mint Cost: 4 import java.util.Scanner;import java.util.ArrayList;import…arrow_forwardUpdate it to create a class Student that includes four properties: an id (type Integer), a name (type String), a Major (type String) and a Grade (type Double). Use class Student to create objects (using buttonAdd) that will be read from the TextFields then save it into an ArrayList. Perform the following queries on the ArrayList of Student objects and show the results on the listViewStudents (Hint: add buttons as needed): d) Use lambdas and streams to calculate the total average of all Students grades, then show the result. e) Use lambdas and streams to group Students by major, then show the results. 1. Ch3HW; import javafx.application.Application; import javafx.fxml.FXMLLoader; import javafx.scene.Parent; import javafx.scene.Scene; import javafx.stage.Stage; public class MainApp extends Application{ @Override publicvoidstart(StageprimaryStage) throwsException { FXMLLoader loader…arrow_forward
- Please assist with non graded problem. Create a Calculator class that implements sum, subtraction, multiplication, and division operations, and throws an appropriate exception whenever the user attempts to perform a division by zero. Then develop a graphical interface (with JavaFx) for your calculator using TextField, Button, and Label objects, or any other graphical objects you like. Graphically display division by zero errors.arrow_forwardPATTERNS: Shapes Using Python, recreate (as close as possible) the pattern given using only one class - the Pattern class. You are only allowed to use PIL.Image and PIL.ImageDraw from the Pillow Library, and pi, cos, and pi. Its data attributes are as follow: width_height – 2-digit tuple containing the width and height of the image space – Image object (with 8-bit RGB color space, specified size, and background color) draw – Image object that performs as the drawing context of the space background – 3-digit tuple of the 8-bit RGB background color of the image or picturearrow_forwardUsing Java You will write the code to perform the following operations using the ArrayList class: Implement a Shoe class, encapsulating the concept of a shoe A shoe has a color, size, and brand. Implement a ShoeStore class, encapsulating the concept of a shoe store. Use the ArrrayList of Shoe objects. Fill the ArrayList object with Shoe objects. Implement a ShoeSearchEnginge class Print Shoe objects in the ArrayList. color: white size: 11 brand: Anne Klein color: yellow size: 13 brand: Calvin Klein color: black size: 9 brand: COACH color: blue size: 5 brand: CLARK color: black size: 7 brand: Cole Han color: blue size: 15 brand: FitFlo color: red size: 9 brand: CLARK Find all Shoe objects with CLARK as a brand in the ArrayList. Find the largest size of a Shoe object in the ArrayList.arrow_forward
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