How to read data from a .csv file and save only some in an arraylist

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How to read data from a .csv file and save only some in an arraylist

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#1 by (1 votes)

1

I am reading a .csv file as follows

BufferedReader rd = new BufferedReader( new FileReader ("C:/Users/user/Documents/running-example.csv"));
         String line = null;
          ArrayList lista = new ArrayList();

        while ((line = rd.readLine()) != null) {

            line = rd.readLine();
            System.out.println(line);
            lista.add(line);

             }

and I would like to know how to search the registered activities within the registers, in this case as: register request, check ticket ... etc. And save them in an arrayList or Array. But which way or method can I use to select or save the registered activity?

1;35654423;30-12-2010:11.02;register request;Pete;50
1;35654425;05-01-2011:15.12;check ticket;Mike;100
1;35654427;07-01-2011:14.24;reject request;Pete;200
2;35654485;30-12-2010:12.12;check ticket;Mike;100
2;35654488;05-01-2011:11.22;decide;Sara;200
3;35654521;30-12-2010:14.32;register request;Pete;50
3;35654524;30-12-2010:16.34;check ticket;Ellen;100
3;35654526;06-01-2011:12.18;reinitiate request;Sara;200
3;35654530;08-01-2011:11.43;check ticket;Pete;100
3;35654533;15-01-2011:10.45;pay compensation;Ellen;200
4;35654643;07-01-2011:12.06;check ticket;Mike;100
4;35654645;09-01-2011:12.02;decide;Sara;200
5;35654711;06-01-2011:09.02;register request;Ellen;50
5;35654714;08-01-2011:11.22;check ticket;Pete;100
5;35654716;11-01-2011:16.18;reinitiate request;Sara;200
5;35654719;16-01-2011:15.50;examine casually;Mike;400
5;35654721;20-01-2011:12.48;reinitiate request;Sara;200
5;35654724;21-01-2011:11.34;check ticket;Pete;100
5;35654726;24-01-2011:14.56;reject request;Mike;200
6;35654873;06-01-2011:16.06;examine casually;Ellen;400
6;35654875;07-01-2011:16.52;decide;Sara;200

java arraylist csv

asked by Rita diaz 26.02.2018 в 19:39

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1 answer

Compare values between two HashMap Problem with my route Route [invoices.obtainproducts] not defined

score 1 · Accepted Answer

The split method, for strings, starts a string based on a string (or a regular expression) and returns an array of the string divided according to the separator.

In your case, when reading each line, what you have to do is something like this:

//definir el vector que contendra la linea separada
String[] linea;
.....
line = rd.readLine();
linea = line.Split(";")
....
//Guardar en el array solo la posicion que queres:
lista.add(linea[3]);

That way the list will only be the part you need.

The complete and corrected code would be:

BufferedReader rd = new BufferedReader( new FileReader ("C:/Users/user/Documents/running-example.csv"));
String line = null;
ArrayList lista = new ArrayList();
String[] linea;
while ((line = rd.readLine()) != null) {
    line = rd.readLine();
    System.out.println(line);
    linea = line.Split(";")
    lista.add(linea[3]);
}

Do not correct the code itself or delete variables that may no longer work, just so that the example is understandable based on your current code.

Split on the web