java comparing-two-csv-files-in-java
import java.io.*;
import java.util.ArrayList;
/* file1 - file2 = file3*/
public class CompareCSV {
public static void main(String args[]) throws FileNotFoundException, IOException
{
String path="D:\\csv\\";
String file1="file1.csv";
String file2="file2.csv";
String file3="p3lang.csv";
ArrayList al1=new ArrayList();
ArrayList al2=new ArrayList();
//ArrayList al3=new ArrayList();
BufferedReader CSVFile1 = new BufferedReader(new FileReader(path+file1));
String dataRow1 = CSVFile1.readLine();
while (dataRow1 != null)
{
String[] dataArray1 = dataRow1.split(",");
for (String item1:dataArray1)
{
al1.add(item1);
}
dataRow1 = CSVFile1.readLine(); // Read next line of data.
}
CSVFile1.close();
BufferedReader CSVFile2 = new BufferedReader(new FileReader(path+file2));
String dataRow2 = CSVFile2.readLine();
while (dataRow2 != null)
{
String[] dataArray2 = dataRow2.split(",");
for (String item2:dataArray2)
{
al2.add(item2);
}
dataRow2 = CSVFile2.readLine(); // Read next line of data.
}
CSVFile2.close();
for(String bs:al2)
{
al1.remove(bs);
}
int size=al1.size();
System.out.println(size);
try
{
FileWriter writer=new FileWriter(path+file3);
while(size!=0)
{
size--;
writer.append(""+al1.get(size));
writer.append('\n');
}
writer.flush();
writer.close();
}
catch(IOException e)
{
e.printStackTrace();
}
}}