Do While Loop - Using Equals?
Sep 30, 2014
having a hard time with my do while loop. for some reason in my else if structure it will break when i using .equals in the do while loop. But if i try doing tmp == "D" || tmp == "d" it will keep looping how can i go about using alternative for .equals?
Here is my code:
do {
Object object = new Object();
System.out.println("For a deposit Enter: D
Withdrawal Enter: W
"
+ "or 'Quit' to exit.");
String tmp = input.next();
if (tmp.equals("D"))
[Code] ....
View Replies
ADVERTISEMENT
Jul 6, 2014
I was reading a book and came across this while loop.
public class Powers {
public static void main (String [] args){
int e;
int result;
for(int i = 0; i < 10; i++){
[Code] .....
This loop presents the following (I'm sure it's not necessary):
2 to the 0 power is 1
2 to the 1 power is 2
2 to the 2 power is 4
2 to the 3 power is 8
2 to the 4 power is 16
2 to the 5 power is 32
2 to the 6 power is 64
2 to the 7 power is 128
2 to the 8 power is 256
2 to the 9 power is 512
I am just having a difficult time understand and grasping this concept. My main issue is result *=2; this is making it very difficult to understand. How is result being replace if it only equals to 1.
View Replies
View Related
Jan 7, 2014
I am trying to override the equals method for my class TeamMember I have two fields:
private Details details;
private double salary;
Code for override I get an error on salary saying cannot invoke equals (double) on the primitive type (double)
Is their something I am missing/coding wrong?
Java Code:
public boolean equals(Object obj) {
//test exceptional cases
//avoid potential NullPointerException/ClassCastException
if ((obj == null) || (this.getClass() != obj.getClass()))
return false;
TeamMember other = (TeamMember) obj; //cast to a TeamMember object
// compare fields details and salary
return this.details.equals(other.details)
&& this.salary.equals(other.salary);
} mh_sh_highlight_all('java');
View Replies
View Related
Mar 28, 2014
Create an equals method that takes an object reference and returns true if the given object equals this object.
Hint: You'll need 'instanceof' and cast to a (Geocache)
So far I have:
public boolean equals(Object O){
if(O instanceof Geocache){
Geocache j=(Geocache) O;
if (this.equals(j)) //I know this is wrong... but I can't figure it out
return true;
}
else return false;
}
I think I have it correct up to the casting but I don't understand what I'm suppose to do with the this.equals(). Also I'm getting an error that I'm not returning a boolean... I get this all the time in other problems. I don't get why since I have to instances of returning booleans in this. "returns true if the given object equals this object" makes no sense to me. I assume the given object, in my case, is 'O'. What is 'this' object referring to?
View Replies
View Related
May 15, 2014
Its that very old question regarding hashcode and equals implementation which i am not getting .
import java.util.*;
public class MyElement {
public static void main(String a[]){
HashSet<Price> lhm = new HashSet<Price>();
lhm.add(new Price("Banana", 20));
lhm.add(new Price("Apple", 40));
[Code] .....
In the above program even if i comment out the Hashcode method , i believe it is still taking the memory address values from the native hashcode method of Object class. but the equals override implentation says that i have two insertions which are same . So as per my logic it should not allow the duplicate element to enter.but its not so ...the duplicate element is well inserted without hashcode .
View Replies
View Related
Jan 12, 2015
All I am trying to do is to make a section of code execute if two strings are equal. The two strings are userId and "A001062". When I use the debugger in Eclipse, I can see the value of userId as "A001062" but whatever string comparison I try never evaluates to true. I have tried
userId=="A001602"
userId.equals("A001602")
"A001602.equals(userId)
Assigning A001062 to a string called AAA and comparing userId to AAA
My code is as follows. I have also attached a screen shot from the Eclipse Debugger which makes me think the string comparison should succeed. I never see the debugger execute the print line nor do I see the print line on the JBOSS console.
String userId = StringUtils.trim(nextLine[HR_USER_ID]);
String AAA="A001062";
if (userId.intern().equals(AAA.intern())) {System.out.print("MKP1: " + userId+"-"+managerId);}
if (userId.compareTo("DTS0428")==0) {System.out.print("MKP2: " + userId+"-"+managerId);}
Attached image(s)
View Replies
View Related
Mar 26, 2014
I have to create a class that has two fields. One called length and the other width. I have to make a method that returns the tract area. Similarly, I also have to make a method that indicates whether two objects have the same fields. Here is the code that I have assembled...so far
// create private fields to hold width and length
private double width;
private double length;
[Code].....
My problem is encountered when writing that equals method
if(length.equals(object.length) && width.equals(object.width))
I get an error saying HTML Code: cannot invoke equals(double) on the primitive type double. Meanwhile, I do see, to realize that when I change my fields to capital "Double." The problem disappears; however, in my class I have never dealt with a situation where I have to use capital d in double. In fact, I don't even know what's the difference between Double and double. I do know what double is but not the other one..
View Replies
View Related
Mar 27, 2014
(Count positive and negative numbers and compute the average of numbers). Write a program that reads an unspecified number of integers, determines how many positive and negative values have been read, and computes the total and average of the input values (not counting zeros). Your program ends with the input 0. Display the average as a floating-point number.
I moved the different boolean statements around, but I'm not getting the sentinel value to end the run. It continues to let me add integers endlessly. The code I wrote is below:
package exerciseFourOne;
import java.util.Scanner;
public class AverageOfIntergers {
public static void main(String[] args) {
// TODO Auto-generated method stub
int positive = 0; // number of positive integers
int negative = 0; // number of negative integers
int sum = 0; // value of sum of integers
[Code] .....
View Replies
View Related
Jul 14, 2014
In Java code, write class called Student with the following features:
• a private instance variable int studentNumber that is initialized to zero.
• a private instance variable String firstName;
• a private instance variable String lastName;
• a constructor which takes an integer argument and two String arguments to initializes the three respective data items.
• a public method with signature equals(Student s) . . .
So far this is my code :
public class student {
private int studentnumber = 0;
public student () {
firstname= "forename":
lastname="surname":
public student (integer studentnumber, string firstname, string lastname) {
this.firstname= firstname
this.lastname= lastname:
My question is how do i add the integer in the argument do i have to use int =? and how would i go about doing the public signature equals...
View Replies
View Related
Mar 25, 2015
Im working on a roman numeral to arabic converter and all I had to do was fill out the conversion method romanToDecimal. But for some reason no matter what number I enter It always says my number is equal to one.
//Quiz 1 EC
import java.util.*;
class Roman {
private String romanNum;
private int decimalNum;
public Roman(){
romanNum = "I";
decimalNum = 1;
[code]....
View Replies
View Related
Oct 2, 2014
For a few days I've been reading about the importance of overriding the equals method. How overriding it actually determines or checks the values stored in the variable. I realize that you can check the values stored in the primitive datatypes with "==", and when you don't override the equals method it acts the same way, right? When used with a reference datatype, "==" or the default equals() method only compares, or sees, if the variable is pointing to the same instance of a class. For some reason, in the examples, what is taking place to actually check the values stored inside the variables.
Here is part of an example (I've added comments for things that are confusing me):
@Override
public boolean equals(Object obj) {
//So we use Object here instead of the class type
// we're overriding this equals method for?
Is this so that we can use it to check different types? (overloading?)
if (obj == this) {
return true;
//Isn't this checking to see if the calling object is the same as the object we're passing to it?
Why doesn't this return false?
}
if (obj == null || obj.getClass() != this.getClass()) {
return false;
}
//How exactly do we check the values stored in each object though?
}
View Replies
View Related
Jan 12, 2015
All I am trying to do is to make a section of code execute if two strings are equal. The two strings are userId and "A001062". When I use the debugger in Eclipse, I can see the value of userId as "A001062" but whatever string comparison I try never evaluates to true. I have tried
userId=="A001602"
userId.equals("A001602")
"A001602.equals(userId)
Assigning A001062 to a string called AAA and comparing userId to AAA
My code is as follows. I have also attached a screen shot from the Eclipse Debugger which makes me think the string comparison should succeed. I never see the debugger execute the print line nor do I see the print line on the JBOSS console.
String userId = StringUtils.trim(nextLine[HR_USER_ID]);
String AAA="A001062";
if (userId.intern().equals(AAA.intern())) {System.out.print("MKP1: " + userId+"-"+managerId);}
if (userId.compareTo("DTS0428")==0) {System.out.print("MKP2: " + userId+"-"+managerId);}
View Replies
View Related
May 5, 2014
I am attempting to override the equals method from the Object class which checks if two variables point towards the same object. I want the method to check if if the argument being passed in(an object) has the same data(instance variables) as the object that's calling this method. A NullPointerException is being thrown; Here is the code.
package javaapplication5;
import java.text.NumberFormat;
import java.util.Scanner;
import java.lang.Object;
public class Product {
private String product;
private String description;
private double price;
[Code] ....
And here is the stack trace
Exception in thread "main" java.lang.NullPointerException
at javaapplication5.Product.equals(Product.java:42)
at javaapplication5.Product.main(Product.java:24)
Java Result: 1
View Replies
View Related
Mar 11, 2015
I need to debug the equals method implementation of a class I've made, but I cannot for the life of me get Netbeans' debugger to step into it. I can step into other methods from the class (most of which implement the methods in an interface) that are called in the main method (just like the equals method). I've tried...
-Disabling all the step filters
-Clearing the Netbeans cache
-Moving the call to the equals method out of the if statement it's in and just calling it as its own statement
-placing breakpoints within the equals method as well as on the call to the method
-placing a method breakpoint on the overridden equals method in addition to the other locations
-Using the shift-F7 version of the step into command
I'm using Netbeans 8.0.1 (I don't know if this is the latest version, but the last time I tried to update everything died and I had to completely remove NB and reinstall it) and JDK 8u05 (I think).
View Replies
View Related
Jul 17, 2014
Here is my code the whole program is working correctly but the Boolean equals and the has code and it is a requirement for the assignment. Why it is not working.
I know there are issues with the code I am new with java and was struggling so I have to clean my code up before I submit the assignment but for right now I have the out put the way I want it except the Boolean and hash code methods always output that the rectangles aren't equal even when I know they are and it outputs the not equal statement twice??
import java.awt.Color;
import java.awt.Dimension;
import java.awt.FlowLayout;
import java.awt.Graphics;
import java.awt.Rectangle;
import java.util.Scanner;
[Code] ....
View Replies
View Related
Mar 26, 2015
How would I create a equals method to compare strings in a class that I'm creating. I need to create the method in my class, and then call it in a driver. How would I do this?
View Replies
View Related
Jan 19, 2014
Write a class encapsulating the concept of a course grade, assuming a course grade has the following attributes: a course name and a letter grade. Include a constructor, the accessor and mutator, and methods toString and equals.Write a client class to test all the methods in your class.
how to test and finish the toString and equals method in this code ?
package labmodule7num57;
import java.util.*;
public class LabModule7Num57 {
// Constructors//
private String name;
private String letterGrade;
public LabModule7Num57 (String name,String letterGrade) {
[code]....
View Replies
View Related
Apr 18, 2014
I am having trouble using the equals method to return the appropriate value using standard arithmetic.
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.FlowLayout;
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
[Code] ....
I know that "inText.setText(Integer.toString(secondOperand));" in the code is wrong, I just don't know the right code...
View Replies
View Related
Jan 25, 2012
I have a simple java program to write which tells the user combination of coins that equals to the amount of change i.e:
user input 87
output:
3 quarters
1 dime
0 nickels
2 pennies
How the program remembers the remainder which is passed to the next column of let say dime
i.e
originalAmount = amount;
quarters = amount /25;
amount = amount % 25; <---- this is confusing for me?!?! how can the integer = integer % 25
dimes = amount / 10; <--- HOW THE PROGRAM remembers the "remainder" instead of the original user input as the code it self tells you dimes = amount where "amount" is what user input NOT remainder.
amount = amount % 10;
so on ....;
What I don't understand is HOW this algorithm works. I mean we have int amount where user inputs the number we get the first calculation amount/25 = how many quarters and then amount %25 WILL tell us about the reminder. By looking at this piece of code I would say that the system should start the calculation for the dimes again from the original number since the code says dimes = amount/10 AND amount = amount%10. My understanding is that the calculation should be done from the original user input.
Book or code it self is not clear for me how the reminder is "REMEMBERED" and then pass on to the next calculation>!?!?
UNLESS the code: amount=amount%25 gets the remainder so the next code under it is REQUIRED to read from the last prompt code.
View Replies
View Related
Jan 27, 2015
I am trying to print a loop inside an array of a greater size than the loop itself. Like for example I have an array of size 7 but it has only 3 elements.
int[] array=new int[7]
array[0]=2;
array[1]=3;
array[2]=4;
now what I want to do is print these three numbers in a loop so that my array[3]=2;array[4]=3;array[5]=4 ...... till the last one. Also the array could be any size and not just 7.
View Replies
View Related
Feb 25, 2014
Here's the code: it's while loop inside a for loop to determine the proper length of a variable:
for (int i = 0; i < num; i++) {
horse[i]=new thoroughbred();
boolean propernamelength = false;
while (propernamelength==false){
String name = entry.getUserInput("Enter the name of horse "
[code]....
I was just wondering what was going on here -- I've initialized the variable, so why do I get this message? (actually the carat was under the variable name inside the parentheses.
View Replies
View Related
Nov 2, 2014
I have everything else working. My problem is that when i type "quit" to close the outer loop. It still runs the inner loop. The National Bank manager wants you to code a program that reads each clients charges to their Credit Card account and outputs the average charge per client and the overall average for the total number of clients in the Bank.
Hint: The OUTER LOOP in your program should allow the user the name of the client and end the program when the name entered is QUIT.In addition to the outer loop, you need AN INNER LOOP that will allow the user to input the clients charge to his/her account by entering one charge at a time and end inputting the charges whenever she/he enters -1 for a value. This INNER LOOP will performed the Add for all the charges entered for a client and count the number of charges entered.
After INNER LOOP ends, the program calculates an average for this student. The average is calculated by dividing the Total into the number of charges entered. The program prints the average charge for that client, adds the Total to a GrandTotal, assigns zero to the Total and counter variables before it loops back to get the grade for another client.Use DecimalFormat or NumberFormat to format the numeric output to dollar amounts.
The output of the program should something like this:
John Smith average $850.00
Maria Gonzalez average $90.67
Terry Lucas average $959.00
Mickey Mouse course average $6,050.89
National Bank client average $1,987.67
Code:
public static void main(String[] args) {
Scanner scan = new Scanner(System.in);
String name = "";
int charge = 0;
int count = -1;
int total = 1;
int grandtotal = 0;
int average = 0;
[code]....
View Replies
View Related
Mar 8, 2014
How to convert this program from a while loop to a for loop.
import java.util.Scanner;
public class LongDivision {
public static void main(String arguments[]){
Scanner input = new Scanner(System.in);
System.out.println("Enter the dividend: ");
[Code] ....
View Replies
View Related
Feb 17, 2014
How do I convert my for loop below to a while and do while loop?
for(int a=1;a<=9;a++){
for(int b=1;b<=a;b++){
System.out.print(a);
}
System.out.println();
[Code] .....
View Replies
View Related
Feb 9, 2015
I am trying to make a program add values from a loop. So what its supposed to do is search through tokens on an imported file. The file lists State, Capital, and then capital population. Then take the population string, turn it into numbers, and then do stuff with the numbers. First I'm supposed to find the Highest and lowest population of the places in the file (which I did without problem), but the finally thing is I'm supposed to add each found population to the last so I can find the average of the populations.
I just cannot seem to grasp how to do that. I THINK I'm supposed to some how store the given value into a variable, but how do I get that variable to add to the new value?
like...?
Get token -> a
b = a
c = a + b
or wait no.....
Java Code :
import java.io.*;
import java.util.Scanner;
public class CapPopS
{
public static void main(String[] args) throws IOException
{
File stateCAP = new File("state-capital-2004population.txt");
if (!stateCAP.exists())
[Code] ....
View Replies
View Related
Feb 9, 2015
My teacher wants me to make a program that counts the amount of steps a student takes a day. The program asks for other info such as name, age, college. However I need to write a loop that will allow the user to enter how many ever steps they took and convert them to miles.how exactly to make the steps entered by the user within the loop be their own individual days like monday tuesday etc. Like the loop will ask how many steps did you take monday.. tuesday.. etc for each time it runs.
package StudentInfo;
import java.util.Scanner;
public class studentinfo {
public static void main (String [] args){
Scanner scan = new Scanner(System.in);
[code]....
View Replies
View Related
