declare array to use it outside whileloop

Question

public void ReadCVS() {
    BufferedReader br = null;
    String line = "";
    String cvsSplitBy = ",";
    int nbA,nbB,nbC;
    nbA=nbB=nbC=0;
    String lval="";
    String test;
    double x = 25;
    double y = 100;
    double z = 200;
    double lp1 = 0;
    try {
        ArrayList<String> l1 = new ArrayList<String>();
        br = new BufferedReader(new FileReader(this.filePath));

        while ((line = br.readLine()) != null) {
            //System.out.println(line);
            // use comma as separator
            String[] tempData = line.split(cvsSplitBy);
            allDatakey.add(tempData[0]);
            allDataValue.add(tempData[1]);

            double j = parseDouble(tempData[1]);
}

//I want to use j here

      if((j>x)&&(j<y)){

        test ="A";
        if(!lval.equals("A")){
        l1.add(test+String.valueOf(nbA));
        nbA++;
        }
        lval="A";

in this code the double j is inside the whileloop , my question is : how can I declare it to use it outside the whillloop buffer ....

Unlike your title suggests, double j is not an array. You can just declare it outside the while loop with double j = -1; (or any other initial value that you would like it to have if there were no lines in the file) and assign it inside the while loop with j = parseDouble(...); — Erwin Bolwidt
– Erwin Bolwidt, Commented Mar 18, 2016 at 8:39
That is a while-loop block (or while block). There isn't any while loop buffer. — jhamon
– jhamon, Commented Mar 18, 2016 at 8:44

Community · Accepted Answer · 2017-05-23 12:07:56Z

1

Declaring an array can be seen here: How do I declare and initialize an array in Java?

If you want to use tempData variable outside of your while loop, you can also copy the array to a new one.

if you only want to get the variable J outside then do this:

double j = 0.0;
while (....) {
   j = parseDouble(tempData[1]
}

edited May 23, 2017 at 12:07

CommunityBot

11 silver badge

answered Mar 18, 2016 at 8:38

Lars Celie

6225 silver badges17 bronze badges

Sign up to request clarification or add additional context in comments.

1 Comment

roge Over a year ago

like that it take j =0.0 outside the whileloop

Tom · Accepted Answer · 2016-03-18 08:52:11Z

1

Try this:

try {
    ArrayList<String> l1 = new ArrayList<String>();
    br = new BufferedReader(new FileReader(this.filePath));
    double j = 0.0;          //shift your J to Outside of the Loop.
    while ((line = br.readLine()) != null) {
        //System.out.println(line);
        // use comma as separator
        String[] tempData = line.split(cvsSplitBy);
        allDatakey.add(tempData[0]);
        allDataValue.add(tempData[1]);
        //change your parseDouble to Double.parseDouble as I Do Here.

        j = Double.parseDouble(tempData[1]); //Initialize Your J here
    // .......
}

Note: j is declared outside of while loop and Initialize inside the loop and again you can use outside of while whatever it contains.

edited Mar 18, 2016 at 8:52

Tom

17.7k17 gold badges48 silver badges55 bronze badges

answered Mar 18, 2016 at 8:38

Vikrant Kashyap

6,9163 gold badges34 silver badges53 bronze badges

4 Comments

roge Over a year ago

if i use it like that , it will be 0.0 outside the loop .

Lars Celie Over a year ago

then something probably goes wrong in your parseDouble method.

Vikrant Kashyap Over a year ago

no . j value will be changed whenever this statement j = parseDouble(tempData[1]); is getting executed.. right what you say ?? J will contain 0.0 If and only if either while condition is false or tempData[1] contailns 0. Thank you

Vikrant Kashyap Over a year ago

then debug your application look intio the array tempData is this variable contains actual expected data that you want to load ?? or not.

Collectives™ on Stack Overflow

declare array to use it outside whileloop

2 Answers 2

1 Comment

4 Comments

Linked

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

1 Comment

4 Comments

Linked

Related