Working on chapter 10 of my book which covers exceptions and file I/O. The only part that does not work is line 40 where it is supposed to print getMessage(). It print's null instead of the more verbose error message.
import java.io.*;
import java.util.*;
import java.text.DecimalFormat;
public class SalesReport2
{
public static void main(String[] args)
{
String filename = "SalesData.txt";
int months = 0;
[Code] ....
temp.txt
123.33
asdf
549.85
dsaf
8456.23
21588.22
652.00
My output when using my test file.
ERROR: SalesData.txt does not exist.
Enter another filename: temp.txt
Nonnumeric data found in file: null
The invalid record will be skipped.
Nonnumeric data found in file: null
The invalid record will be skipped.
Number of months: 5
Total Sales: 31,369.63
Average Sales: 6,273.93
I then removed the try catch so that I could get a stacktrace
import java.io.*;
import java.util.*;
import java.text.DecimalFormat;
public class SalesReport2a
{
public static void main(String[] args)
[Code] ...
This was the output.
ERROR: SalesData.txt does not exist.
Enter another filename: temp.txt
Exception in thread "main" java.util.InputMismatchException
at java.util.Scanner.throwFor(Unknown Source)
at java.util.Scanner.next(Unknown Source)
at java.util.Scanner.nextDouble(Unknown Source)
at SalesReport2a.main(SalesReport2a.java:32)
I also pulled the copy of the code from the CD that came with the book and it's output is the same as my code.
The image in the book shows that the error should be more informative though.
what I get
Nonnumeric data found in file: null
vs
what I should get
Nonnumeric data found in file: For input string: "asdf"
The getGraphics() method in my constructor is returning a nullPointerException and I can't figure out why. This class is extending a JPanel and I thought calling super() would fix it because it makes sense that the JPanel would initialize its graphics object in the constructor, but that didn't fix it. The line that produces the error is in bold. I've narrowed it down to the getGraphics() method is returning null, so the next line that calls the graphics object is actually the one that produces the error.
int leftMargin = 2, rightMargin = 2, topMargin = 2, bottomMargin = 2; int lineSpacing = 1; int currentX = leftMargin, currentY = topMargin; Font defaultFont, customFont; public HTMLFrame(){ super();
[Code] ....
print(String) is a method I made that draws lines of text on the graphics object, similar to System.out.println(String) in the command prompt.
I have embed a query in the JAVA to retrieve the data from the back end and I use Oracle for back end. What I'm trying to do is in my query has been shown below. The issue here is that result set returns the NULL. But fine when I change the query "SELECT 5 FROM DUAL" and it returns 5 for me which right. When I try to run the same at the back end as a query I'm getting proper result.
public String getReturnPart(String partNumberIn) { //int returnPartNumber = 0; String query = "SELECT COUNT(*) AS CHECK1 FROM PART_MASTER PM,UNITS_OF_MEASURE UOM WHERE PM.PART_NUMBER = '" + partNumberIn + "' AND PM.UNIT_OF_ISSUE = UOM.UNIT_OF_MEASURE AND UOM.UNIT_TYPE = 0 "; //String query = "SELECT 5 AS CHECK1 FROM DUAL"; This returns fine as "5" ResultSet result = null;
I'm using NetBeans to create this project and I have the gui registering text boxes, but it won't retrieve what the user entered, so the calculate button returns a null exception error.
In Oracle SQL, when you do trim(column_name), if column_name is blank spaces only (say datatype is CHAR(8)), then "trim(column_name) is null" is true.
In JPQL, if you do "TRIM ( BOTH FROM p.column_name ) is null", does it evaluate to true just like in Oracle SQL?
The reason I'm asking, is my colleague wrote some code in JPQL like below:
... TRIM ( BOTH FROM CONCAT(p.column_name, '#@') ) = '#@'
He said he originally wanted to compare the TRIM result to empty String '', but the result is false, so he concat the column to some junk.
So if after the TRIM, the result is the same junk he added, then the column contains only blanks. I think this works but there could a simpler way to do it.
Im trying to HTML/JavaScript ecode the getmessage calls in the code listed below. The code below is a snippit from a program which is used to handle a failed authentication attempt.
In the following piece of code Iam confused as to where the InputMismatchException in the catch block is thrown on the first place? Is the InputMismatchException thrown automatically with declaring to throw the exception?
import java.util.*;
public class InputMismatchExceptionDemo { public static void main(String[] args) { Scanner input = new Scanner(System.in); boolean continueInput = true;
I'm working on an assignment for my java class and I am currently stuck with an error/exception,
Exception in thread "main" java.util.InputMismatchException at java.util.Scanner.throwFor(Scanner.java:864) at java.util.Scanner.next(Scanner.java:1485) at java.util.Scanner.nextInt(Scanner.java:2117) at java.util.Scanner.nextInt(Scanner.java:2076) at BabyNames.search(BabyNames.java:45) at BabyNames.main(BabyNames.java:20)
I input my name, which is able to get my name from the names.txt, however after that, it hits an exception and does not go further on.Also please use the names,
JIMMY JIMMIE JIMMU JIMI (All can be lowered case), because I am unable to upload the full file for it is very big.
//Jimmy //Programming Assignment #6: Baby Names //This program is going to scan a file with data //about names and their popularity starting from the 1890's //and will display their popularity over the years in 10 intervals.
For this program, I have to run a slot machine. It runs until right before the do while loop and then I receive the error: Exception in thread "main" java.util.InputMismatch.Exception. Searching around, someone said it was a scanner error and adding a call keyboard.nextLine(); fixes the problem- however with that I receive the same error.
Code : import java.util.Scanner; import java.util.Random; import java.io.*; public class SlotMachineSimulation { public static void main(String[] args) throws IOException { int number;
public class Test { public static void main(String[] args) { Car c = new Car(); c.setInf("toyota", "red"); System.out.println("name: "+ c.brand + " colour: " + c.colour);
[code]....
Why do I get the result brand null, colour null? I know what null means but what am I missing here?
I have a routine that returns a boolean. If any of a series of tests fails, the routine returns false, otherwise it returns true. For example, the routine might test for whether or not an integer is both odd and greater than 99, thus:
public boolean oddAndOld(int x) { if (x % 2 == 0) return false; if (x < 100) return false; return true; }
I like the above because it suggests that "true" is the condition that applies if the incoming parameter meets all the required criteria. But I've sometimes seen this style used:
public boolean oddAndOld(int x) { if (x % 2 == 0) return false; if (x < 100) return false; else return true; }
I like this less because, among other things, if that last criterion is removed, the "else/return true" must be moved up into the immediately preceding test (or else leave some funny whitespace, depending on how you go about removing the departing "if" statement), but it does avoid suggesting that "return true" is hard-coded (that is, it reinforces that "true" is a conditional return value, not inevitable).
I've been trying to make a class that has a toString method that displays the board at the same time displays the value of each index of a 2d character array inside of the code. My professor has made the client print the method. I assumed since he was printing it on the client we had to return a string that gives us this.The number 2 is part of the 2d character array while the rest of the index values are just space characters.
I had trouble figuring out how to return this so I started testing it out in another file.
public static void main(String[] args) { // TODO Auto-generated method stub char[][] myHidingPlaces; myHidingPlaces = new char[5][3]; myHidingPlaces[0][0] = 'p'; char play = '1'; for (int i = myHidingPlaces.length-1; i >= 0 ; i--) {
Basically, it's to write a method that takes in, and then returns another array, whose first element is the average of the first two numbers, last element is the average of the last two, and then everything else is just the average of that index, the one before, and the one after. {1, 2, 4, 8} would return {1.5, 2.33333, 4.66666, 6}.I'm currently getting everything fine, except am not getting the last number (i.e. '6').
public class Arrays { public static void main(String [] args){ double [] a1 = {1, 2, 4, 8}; for (int i = 0; i < a1.length; i++) System.out.println(a1[i]);
Before I created the data file are the points of x and y I created a model class that represents the graph. I have a problem with making a function that returns the panel of the graph.
Attached File(s)
data.cvs.txt (726bytes) Number of downloads: 12 chart.txt (3.72K) Number of downloads: 10
I need to create a method that returns a new array containing the componentwise sum of its arguments(if length is the same). For instance, if the input arrays are {0,1, 2} and {2, 2, 3} then the output is {0+2, 1+2, 2+3}, i.e. {2,3,5}.If the input arrays have different numbers of elements, the method should return null.
I came with something like this, however i dont know how to make a copy of an array from two arrays. My code obviously wont compile. package whatever;
import java.util.Arrays; public class hhhh { public static void main(String[] args) { double [] a = {1,2,3}; double [] b = {2,3,4};
I'm currently having trouble with a Breakout clone that I'm working on when I want to change the scenes of the game. When I start out with the main menu and I hit play, the main menu calls for the StateManager to remove the MainMenu and then to add the GameState to start playing through the levels. But, whenever this is done it just gives a NullPointerException and freezes the game. I know the code for initially starting a State is fine because that is the same way the MainMenu is loaded but there seems to be an issue with changing from one to another...
This is the StateManager class that adds and removes the States/Canvases to and from the JFrame/Main class:
public class StateManager { private ArrayList<State> states; private int currentState; private JFrame gameFrame; public StateManager(JFrame gameFrame) { this.gameFrame = gameFrame; states = new ArrayList<State>();
[Code] ....
I've tried messing around with the order of which things are added/loading from the StateManager but am just failing to see what I did wrong.
I'm currently having trouble with a Breakout clone that I'm working on when I want to change the scenes of the game. When I start out with the main menu and I hit play, the main menu calls for the StateManager to remove the MainMenu and then to add the GameState to start playing through the levels. But, whenever this is done it just gives a NullPointerException and freezes the game. I know the code for initially starting a State is fine because that is the same way the MainMenu is loaded but there seems to be an issue with changing from one to another...
This is the StateManager class that adds and removes the States/Canvases to and from the JFrame/Main class: package com.pathtocreating.Breakout_V2.state;
import java.awt.BorderLayout; import java.util.ArrayList; import javax.swing.JFrame; public class StateManager { private ArrayList<State> states;
[Code] ....
The code that calls the change of state in MainMenuState is called in the update method:
Here is the full stack trace when clicking the area to change states:
Exception in thread "Thread-2" java.lang.NullPointerException at sun.java2d.SunGraphics2D.validateColor(Unknown Source) at sun.java2d.SunGraphics2D.<init>(Unknown Source) at sun.awt.image.SunVolatileImage.createGraphics(Unknown Source)
[Code] ...
It gives that same value both before and after clicking on the region.
Printing out b after the State is changed to GameState gives the following:
What is exact difference between them? Another thing is when I check (a==b) it retuns me false, but when I check a.equals(b) it returns me with true. Why So?
Write a Java method that returns the largest value of an array of doubles passed to the method as an argument.
Back into java wasn't sure how to do it for doubles did one in the main for integers and then added a method changed from int to double and now i'm lost as go why its not working.
package kickstarter9; public class Kickstarter9 { public static void main(String[] args){ double myList; double[] myList = {6.0, 4.1, 2.4, 6.8, 1.9, 9.4, 2.8, 4.6, 9.3}; // find the largest value in the list
I have to create a program that calculates the nth Fibonacci number and returns that to the user. Fibonacci said his number sequence would describe the ideal breeding patterns of immortal rabbits. So, you are going to make this vision a reality.
First, take in a numeric value from the user and calculate that value in the fibonacci series. Next, find an image of a rabbit and display the image on a GUI (put the image as an icon on a label!) the number of times returned by the algorithm (Put all the aforementioned labels on one panel with FlowLayout!).
You need to remove the old images from the Panel. Probably the easiest way to do this is to create a whole new panel and remove the old one (hint: the remove method of JPanel should come in handy)
You could use an array of JLabels You will need to create a new JLabel and add each member of the array to the panel I should be able to scroll to see any images that are off screen
I am having difficultly on to making the array list for JLabel, and getting the Fibonacci sequence to show the pictures of rabbits. Below is my current code.
import java.awt.FlowLayout; import java.awt.*; import java.awt.event.*; import javax.swing.*; public class Rabbit extends JFrame
