Debug Database connection : Connection « Database SQL JDBC « Java

Debug Database connection

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

public class TestDebug_MySQL {
  public static Connection getConnection() throws Exception {
    String driver = "";
    String url = "jdbc:mysql://localhost/octopus";
    String username = "root";
    String password = "root";
    return DriverManager.getConnection(url, username, password);

  public static int countRows(Connection conn, String tableName) throws SQLException {
    Statement stmt = null;
    ResultSet rs = null;
    int rowCount = -1;
    try {
      stmt = conn.createStatement();
      rs = stmt.executeQuery("SELECT COUNT(*) FROM " + tableName);
      // get the number of rows from the result set;
      rowCount = rs.getInt(1);
    } finally {

    return rowCount;

  public static void main(String[] args) {
    Connection conn = null;
    try {
      PrintWriter pw = new PrintWriter(new FileOutputStream("mysql_debug.txt"));
      conn = getConnection();
      String tableName = "myTable";
      System.out.println("tableName=" + tableName);
      System.out.println("conn=" + conn);
      System.out.println("rowCount=" + countRows(conn, tableName));
    } catch (Exception e) {
    } finally {
      try {
      } catch (SQLException e) {

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19.String java.sql.DriverPropertyInfo.value (Get current value)
20.String java.sql.DriverPropertyInfo.description (Get description of property)
21.String[] java.sql.DriverPropertyInfo.choices (Get possible choices for property; if null, value can be any string)
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