JDBCExample.java

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

public class JDBCExample {

    public static void main(String[] argv) {

        System.out.println("-------- PostgreSQL " +
            "JDBC Connection Testing ------------");

        try {

            Class.forName("org.postgresql.Driver");

        } catch (ClassNotFoundException e) {

            System.out.println("Where is your PostgreSQL JDBC Driver? " +
                "Include in your library path!");
            e.printStackTrace();
            return;

        }

        System.out.println("PostgreSQL JDBC Driver Registered.");

        Connection connection = null;
        Statement stmt = null;

        try {

            connection = DriverManager.getConnection(
                "jdbc:postgresql://127.0.0.1:15432/test", "user",
                "");
            String sql = "SELECT * from people";
            stmt = connection.createStatement();
            ResultSet rs = stmt.executeQuery(sql);
            //STEP 5: Extract data from result set
            while (rs.next()) {
                //Retrieve by column name
                String name = rs.getString("name");
                int age = rs.getInt("age");

                //Display values
                System.out.print("Age: " + age);
                System.out.println(", Name: " + name);
            }
            rs.close();

        } catch (SQLException e) {

            System.out.println("Connection Failed. Check output console");
            e.printStackTrace();
            return;

        }

        if (connection != null) {
            System.out.println("Connection test succeeded.");
        } else {
            System.out.println("Failed to make connection.");
        }
    }

}