Reading a column from CSV file using JAVA

Question

Hi I am trying to read a CSV File called test csv in JAVA   Below is my code     import java io BufferedReader  import java io FileReader   public class InsertValuesIntoTestDb         SuppressWarnings  rawtypes       public static void main String   args  throws Exception                   String splitBy                BufferedReader br   new BufferedReader new FileReader  test csv             String line   br readLine            while line  null                String   b   line split splitBy                System out println b 0                      br close             This is my CSV File  test csv    a f w b numinst af ub 1RW 800 64 22 1 48 2 true 1RW 800 16 39 1 48 2 true 1RW 800 640 330 1 48 2 true 1RW 800 40 124 1 48 2 true 1RW 800 32 104 1 48 2 true 1RW 800 8 104 1 48 2 true 1R1W 800 65536 39 1 96 96 true 1R1W 800 2048 39 1 96 96 true 1R1W 800 8192 39 1 48 48 true   I am trying to print the first column in the csv  but the output I get is only a in an infinite loop   Can anyone please help me fix this code to print the entire first column  Thanks

User · Accepted Answer

Read the input continuously within the loop so that the variable line is assigned a value other than the initial value

while ((line = br.readLine()) !=null) {
  ...
}

Aside: This problem has already been solved using CSV libraries such as OpenCSV. Here are examples for reading and writing CSV files

User · Answer

You are not changing the value of line  It should be something like this   import java io BufferedReader  import java io FileReader   public class InsertValuesIntoTestDb       SuppressWarnings  rawtypes     public static void main String   args  throws Exception         String splitBy              BufferedReader br   new BufferedReader new FileReader  test csv           while  line   br readLine       null              String   b   line split splitBy              System out println b 0                  br close             readLine returns each line and only returns null when there is nothing left  The above code sets line and then checks if it is null

User · Answer

Splitting by comma doesn t work all the time for instance if you have csv file like    Name     Job     Address   Pratiyush  Singh     Teacher     Berlin  Germany    So  I would recommend using the Apache Commons CSV API       Reader in   new FileReader  input1 csv        Iterable lt CSVRecord gt  records   CSVFormat EXCEL parse in       for  CSVRecord record   records          System out println record get 0

User · Answer

If you are using Java 7   you may want to use NIO 2  e g      x274d  Code   public static void main String   args  throws Exception        File file   new File  test csv         List lt String gt  lines   Files readAllLines file toPath                 StandardCharsets UTF 8        for  String line   lines            String   array   line split      -1           System out println array 0                 x274d  Output   a 1RW 1RW 1RW 1RW 1RW 1RW 1R1W 1R1W 1R1W

[java] Reading a column from CSV file using JAVA

Examples related to java

Examples related to csv