Source Code for Simple Database Program

This database program is simple, it uses the sqlite jar for connecting to the SQLite database.

It can store a file's text in a database, update that text, and extract that text back out to it's original file name.

It's pretty quick and dirty. There might be better ways to handle some of it, but I just wanted to make sure it would do what I wanted it to do.

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;
import java.sql.PreparedStatement;
import java.sql.ResultSet;

import java.io.File;
import java.io.IOException;
import java.nio.charset.StandardCharsets;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.Paths;

public class Sample {

  private Connection conn = null;

  public Sample() {

  }

  public void init() {

    try {
      String url = "jdbc:sqlite:sample.db";
      conn = DriverManager.getConnection(url);

    } catch (SQLException e) {
      e.printStackTrace();
    }
  }

  public void saveData(String filename) {
    try {
      String fileContent = new String(Files.readAllBytes(Paths.get(filename)));
      String sql = "insert into files(name, content) values(?,?)";
      PreparedStatement pstmt = conn.prepareStatement(sql);
            pstmt.setString(1, filename);
            pstmt.setString(2, fileContent);
            pstmt.executeUpdate();
    } catch (IOException e) {
      e.printStackTrace();
    } catch (SQLException e) {
      e.printStackTrace();
    }
  }

  public void updateData(String filename) {
    try {
      String fileContent = new String(Files.readAllBytes(Paths.get(filename)));
      String sql = "update files set content = ? where name = ?";
      PreparedStatement pstmt = conn.prepareStatement(sql);
            pstmt.setString(1, fileContent);
            pstmt.setString(2, filename);
            pstmt.executeUpdate();
    } catch (IOException e) {
      e.printStackTrace();
    } catch (SQLException e) {
      e.printStackTrace();
    }
  }

  public void exportData(String id) {
    StringBuilder sb = new StringBuilder();
	    String sql = "select * from files where id = ?";
	    ResultSet rs = null;
	    try {
	    	PreparedStatement pst = conn.prepareStatement(sql);
        pst.setString(1, id);
	    	rs = pst.executeQuery();

        while (rs.next()) {
          Path path = Paths.get(rs.getString("name"));
		      Files.writeString(path, rs.getString("content"), StandardCharsets.UTF_8);
        }
	    } catch (SQLException e) {
	    	e.printStackTrace();
	    } catch (IOException e) {
        e.printStackTrace();
      }
  }

  public static void main(String[] args) {
    if (args.length != 2) {
      System.err.println("ERROR: You must provide two arguments.");
      System.err.println("insert or update");
      System.err.println("filename to insert or update");
      return;
    }
    Sample sample = new Sample();
    sample.init();
    if (args[0].equals("insert")) {
      sample.saveData(args[1]);
    } else if (args[0].equals("update")) {
      sample.updateData(args[1]);
    } else if (args[0].equals("export")) {
      sample.exportData(args[1]);
    }

  }
}