Why should you use StringBuffer objects instead of String objects in a program that makes lot of changes to strings? 2. Each of the numeric wrapper classes has a static toString method. What do these methods do

Hello, I don’t understand this Java Question may someone help me out, may you also type out the code please and take a screenshot ?

correct answer please

Hello, can you please help me with this parts because i am struggling with much with this problem. Can you please draw a state diagram for both because I am a visual learner. Can you help me with this problem and can you label the parts as well so I can follow along.

Fix the problem with this piece of code: public class SomethingIsWrong { public static void main(String[] args) { Rectangle myRect; myRect.width = 40; myRect.height = 50; System.out.println("myRect's area is " + myRect.area()); } }

Using java on Eclipse

String Builder In this lab, we learn how StringBuilder class works and why it is efficient. Type up the code below, run it and submit ONLY the output. import javax.swing.JOptionPane; public class StringBuilderDemo ( public static void main(String[] args) ( StringBuilder nameString = new StringBuilder ("Barbara"); int nameStringCapacity System.out.println("Capacity nameString.capacity(); nameStringCapacity); of nameString is " + StringBuilder addressString = null; addressString new StringBuilder ("6311 Hickory Nut Grove Road"); int addStringCapacity addressString.capacity(); System.out.println("Capacity of addressString is addStringCapacity); nameString.setLength (20); System.out.println("The name is " + nameString + "end"); addressString.setLength (20); System.out.println("The address is + addressString);

Implement a new concat method in the String class you worked on for HW2. The method should return a new String object that represents the text you would end up with if the argument String were "added onto the end of" this String. For example, in the code below, the String object answer should represent the text "bookstore" and true should be printed the screen. char[] bookA = {'b', 'o', 'o', 'k'}; char[] storeA = {'s', 't', 'o', 'r', 'e'}; char[] bookstoreA = {'b', 'o', 'o', 'k', 's', 't', 'o', 'r', 'e'}; String book = new String(bookA); String store = new String(storeA); String bookstore = new String(bookstoreA); String answer = book.concat(store); System.out.println(answer.equals(bookstore)); In the text area below, type in your definition of the concat method. (In other words, type in the code that should replace the //TODO comment.) Your code cannot call any methods. public class String { private char[] data; public String(char[] value) { data = new...

Please use java. In this assignment, you will implement a simple class called ​CustomString​. This class represents a more customizable version of a String, with additional attributes and methods. For example, the CustomString class has a "reverse" method which returns a new string version of the current string where the capitalization is reversed (i.e., lowercase to uppercase and uppercase to lowercase) for the alphabetical characters specified in a given argument. For CustomString "abc, XYZ; 123.", calling reverse("bcdxyz@3210.") will return "aBC, xyz; 123.". The CustomString class also has a "remove" method which returns a new string version of the current string where the alphabetical characters specified in a given argument, are removed. For CustomString "my lucky numbers are 6, 8, and 19.", calling remove("ra6") will return "my lucky numbers e 6, 8, nd 19.". There are 5 methods that need to be implemented in the CustomString class: ●くろまる getString() - Returns the current string. ●くろまる...

When testing this java program I get a java.lang.NullPointerException for 3 sections of the function, specifically String remove, String reverse and String filterLetters

i need help with my java program. Its having trouble running and I need help making sure it works. Please post the results and output for it. Heres my code and below are also what the program is supposed to do.import java.util.*; public class SimpleCalculator { private final String input; private int position; private boolean hasDivByZero = false; private Map<String, String> symbolTable; private List<String> instructions; public SimpleCalculator(String input) { this.input = input; this.position = 0; this.symbolTable = new HashMap<>(); this.instructions = new ArrayList<>(); } public static void main(String[] args) { SimpleCalculator calculator = new SimpleCalculator("3 + 5 * (2 - 1)"); calculator.parseExpression(); if (calculator.hasDivByZero) { System.out.println("Error: division by zero"); } else { System.out.println("Result: " + calculator.instructions);...

java question: what is the name of the class to tokenize a string?tokenizer, Tokenizier, StringTokenizer,or stringTokenizer

In some cases, a class depends on itself. That is, an object of one class interactswith another object of the same class. To accomplish this, a method of the classmay accept as a parameter an object of the same class.The concat method of the String class is an example of this situation. Themethod is executed through one String object and is passed another String object as a parameter. Here is an example:str3 = str1.concat(str2);The String object executing the method (str1) appends its characters to thoseof the String passed as a parameter (str2). A new String object is returned asa result and stored as str3. Write java code to implement given conditions