how to write arraylist to csv file in java code example

Example 1: java create csv file from list

String input = "[\"user1\",\"track1\",\"player1\", \"user1\",\"track2\",\"player2\", \"user1\",\"track3\",\"player3\"]";
        input = input.substring(1, input.length() - 1); // get rid of brackets
        String[] split = input.split(" ");

        FileWriter writer = new FileWriter("/Users/user/tmp/csv/sto1.csv");

        for(String s : split) {
            String[] split2 = s.split(",");
            writer.write(Arrays.asList(split2).stream().collect(Collectors.joining(",")));
            writer.write("\n"); // newline
        }

        writer.close();

Example 2: convert arraylist to csv file java

import java.util.ArrayList;
import java.io.BufferedWriter;
import java.io.FileWriter;
import java.io.File;
import java.io.IOException;
class test
{
    public static void main(String arg[])throws IOException
    {
        ArrayList<String> list1 = new ArrayList<>();
        list1.add("2212");
        list1.add("gmail.com");

        ArrayList<String> list2 = new ArrayList<>();
        list2.add("192.168.0.175");
        list2.add("403");
        list2.add("192.168.0.26");
        list2.add("1809");

        File file = new File("test.csv");
        FileWriter fw = new FileWriter(file);
        BufferedWriter bw = new BufferedWriter(fw);

        bw.write("Domain,Total");
        bw.newLine();
        for(int i=0;i<list1.size();i++)
        {
            bw.write(list1.get(i+1)+","+list1.get(i++));
            bw.newLine();
        }
        bw.write("\nApplication,Total");
        bw.newLine();
        for(int i=0;i<list2.size();i++)
        {
            bw.write(list2.get(i++)+","+list2.get(i));
            bw.newLine();
        }
        bw.close();
        fw.close();
    }
}

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Java Example