Needs some Java help.

[Achán hiNidráne]

Hey all:

Working on some Java class homework and I need some help. I'm supposed to write a program that asks for a month and creates a one dimensional array that holds the temperature for each day of the month then it creates a printout of each day of the month then gives the average temp. I'm I've got the first part done, but it blows up with an out of bounds exception when I try to run the second part. Here's my code:

public class temperature
{
private int dayTemp[];
private String month;

public void temperatureMethod()
{

System.out.println("Please type in the month:");
java.util.Scanner scan = new java.util.Scanner(System.in);
String month = scan.next();
if (month.equals("February")){
dayTemp = new int[28];
}
else if(month.equals("April") || month.equals("June") || month.equals("September") || month.equals("November")){
dayTemp = new int[30];
}
else if (month.equals("January") || month.equals("March") || month.equals("May") || month.equals("July") || month.equals("August") || month.equals("October") || month.equals("December")){
dayTemp = new int[31];
}
else {
System.out.println("Please enter a valid month.");
}
int i=0;
int j=1;
while(i < dayTemp.length){
System.out.println("Enter temperature for day: " + j );
dayTemp = scan.nextInt();
i++;
j++;
}
}

public void printTempMethod()
{
System.out.println("Month: " + month);
int highTemp=0;
int lowTemp=0;
int averageTemp=0;
System.out.println("Month: " + month);
int k=0;
int l=0;
while(l <= dayTemp.length){
System.out.println(dayTemp[k]); <---Blue J says THIS is the point where the out of bound exception is occurring.
k++;
l++;
}
for (int m = 0; m < dayTemp.length; m++){
averageTemp += dayTemp[m];
}
System.out.print("Average: " + averageTemp);

Can anyone give me a clue what I'm doing wrong?

 

[roger]

"while l <= dayTemp.length"

you are going 1 past the bounds of the array.

 

[Achán hiNidráne]

"while l <= dayTemp.length"

you are going 1 past the bounds of the array.

That's supposed to be a lower case "L."

Actually the debugger portion of Blue J is highlighting this:

System.out.println(dayTemp[k]);

 

[Wrathernaut]

Just curious why you're using two different variables here when they both start at 0 and increment each time through that while loop.

The first time you go through it, one of your variable start at 1, the other at 0:

int i=0;
int j=1;
while(i < dayTemp.length){
System.out.println("Enter temperature for day: " + j );
dayTemp = scan.nextInt();
i++;
j++;

While the second time, you start both at 0:

int k=0;
int l=0;
while(l <= dayTemp.length){
System.out.println(dayTemp[k]); <---Blue J says THIS is the point where the out of bound exception is occurring.
k++;
l++;

My java and addressing arrays in it ain't that great, but did you need to have l = 1 like the first loop?

 

[Achán hiNidráne]

OK, I think I got it sorted out. It's running fine now. Thanks.