How to read a CSV file via Java

In this blog post, I will be covering how you can read a CSV file via Java.

What is a CSV file?

CSV stands for Comma Separated Values.  The fields in a CSV file are separated by commas.  So for example, a CSV file will be seen in Notepad as follows:

 

However, if you open the same CSV file in Excel and will be seen as follows:

 

A CSV file is used to store tabular data. You can open a CSV file in Microsoft Excel.

Code to read CSV file

Consider the following code sample:

package learnjava.io;import java.io.BufferedReader;import java.io.File;import java.io.FileNotFoundException;import java.io.FileReader;import java.io.IOException;public class ReadCSVDemo {public static void main(String[] args) {String fileName="F:/Test.csv";try {BufferedReader br = new BufferedReader(new FileReader(fileName));String str = br.readLine();while(str != null){String[] contents = str.split(",");for(String cell:contents){System.out.print(cell);}str = br.readLine();System.out.println();}} catch (FileNotFoundException e) {// TODO Auto-generated catch blocke.printStackTrace();}catch (IOException e) {// TODO Auto-generated catch blocke.printStackTrace();}}}

 

First, the input file is read line by line using a BufferedReader. Each line is split using the String,split method and its contents are printed.

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