CountRows_MySQL.java Source code

Introduction

Here is the source code for CountRows_MySQL.java

Source

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

public class CountRows_MySQL {

    public static Connection getConnection() throws Exception {
        String driver = "org.gjt.mm.mysql.Driver";
        String url = "jdbc:mysql://localhost/octopus";
        String username = "root";
        String password = "root";

        Class.forName(driver); // load MySQL driver
        Connection conn = DriverManager.getConnection(url, username, password);
        return conn;
    }

    public static int countRows(Connection conn, String tableName) throws SQLException {
        // select the number of rows in the table
        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
            rs.next();
            rowCount = rs.getInt(1);
        } finally {
            rs.close();
            stmt.close();
        }
        return rowCount;
    }

    public static void main(String[] args) {
        Connection conn = null;
        try {
            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) {
            e.printStackTrace();
            System.exit(1);
        } finally {
            // release database resources
            try {
                conn.close();
            } catch (SQLException e) {
                e.printStackTrace();
            }
        }
    }
}