How do I create a connection to MS Access database?

The following example show you how to create a connection to Microsoft Access databases. To allow the database access to be authenticated, the security user account can be added from File -> Info -> Users and Permissions screen.

Just like accessing any other databases in the Java platform we need a JDBC driver. To access Microsoft Access databases we can use UCanAccess, an open-source pure Java JDBC driver for Microsoft Access databases, it allows us to manipulate data in various versions of MS Access databases.

Here what we do in the code snippet below:

  • Prepare USERNAME and PASSWORD that will be used for accessing the database.
  • Define the database JDBC URL which contains the path to MS Access file.
  • Get the connection in try-with-resource statement using the DriverManager.getConnection() method and passes URL, USERNAME, and PASSWORD as arguments.
  • The connection will automatically closed by the try-with-resource when finished.
package org.kodejava.jdbc;

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

public class MSAccessConnect {
    private static final String USERNAME = "admin";
    private static final String PASSWORD = "admin";

    private static final String URL =
            "jdbc:ucanaccess://C:/Users/wayan/Temp/kodejava.mdb;";

    public static void main(String[] args) throws Exception {
        try (Connection connection = DriverManager.getConnection(URL, USERNAME, PASSWORD)) {
            // Do something with the connection here!
            System.out.println("connection = " + connection);
        } catch (SQLException e) {
            e.printStackTrace();
        }
    }
}

The connection object printed from the code above:

connection = net.ucanaccess.jdbc.UcanaccessConnection@63376bed[C:\Users\wayan\Temp\kodejava.mdb]

Before JDK 8, the sun.jdbc.odbc.JdbcOdbcDriver driver can be used to connect to Microsoft Access databases. On the example below we can either connect through the DSN created previously on the Windows system, or we can create it in our program as the long URL below.

In Microsoft Access 2003, to allow the database access to be authenticated the security user account can be added from Tools -> Security -> User and Group Accounts menu.

package org.kodejava.jdbc;

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

public class MSAccessODBCBridge {
    private static final String USERNAME = "admin";
    private static final String PASSWORD = "admin";
    private static final String DRIVER = "sun.jdbc.odbc.JdbcOdbcDriver";

    // If you want to use you ODBC DSN
    //private static final String URL = "jdbc:odbc:TestDB";
    private static final String URL =
            "jdbc:odbc:Driver={MICROSOFT ACCESS DRIVER (*.mdb, *.accdb)};" +
            "DBQ=C:/Users/wayan/Temp/kodejava.mdb;";

    public static void main(String[] args) throws Exception {
        Class.forName(DRIVER);
        try (Connection connection = DriverManager.getConnection(URL, USERNAME, PASSWORD)) {
            // Do something with the connection here!
            System.out.println("connection = " + connection);
        } catch (SQLException e) {
            e.printStackTrace();
        }
    }
}

The connection object printed from the code above:

connection = sun.jdbc.odbc.JdbcOdbcConnection@4ec4f498

Maven Dependencies

<dependency>
  <groupId>io.github.spannm</groupId>
  <artifactId>ucanaccess</artifactId>
  <version>5.1.1</version>
</dependency>

How do I calculate process elapsed time?

This example shows us how to use the System.nanoTime() method to get the amount of time a process take place. Please be aware that the nano time value is not related to the real world time value.

package org.kodejava.lang;

public class ElapsedTimeExample {
    public static void main(String[] args) {
        // Get the start time of the process
        long start = System.nanoTime();
        System.out.println("Start: " + start);

        // Just do some a bit long process calculating the total value
        // of even number from zero to 10000
        int totalEven = 0;
        for (int i = 0; i < 10000; i++) {
            if (i % 2 == 0) {
                totalEven = totalEven + i;
            }
        }

        // Get the end time of the process
        long end = System.nanoTime();
        System.out.println("End  : " + end);

        long elapsedTime = end - start;

        // Show how long it took to finish the process
        System.out.println("The process took approximately: "
            + elapsedTime + " nano seconds");
    }
}

And example of the result are:

Start: 35034476484699
End  : 35034477434200
The process took approximately: 949501 nano seconds

How do I create a Hello World Applet?

The code below demonstrate the very basic of Java applet. Applet is a small Java application that can be embedded on the web browser.

package org.kodejava.applet;

import java.applet.*;
import java.awt.*;

public class HelloWorldApplet extends Applet {
    public void init() {
    }

    public void start() {
    }

    public void stop() {
    }

    public void destroy() {
    }

    public void paint(Graphics g) {
        g.setColor(Color.GREEN);
        g.drawString("Hello World", 50, 100);
    }
}

To display the applet we need to create an HTML document. Here is a simple example of the document.

<!DOCTYPE html>
<html lang="en">
<head>
    <title>Hello World Applet</title>
</head>

<body>
<applet
        code="org.kodejava.applet.HelloWorldApplet"
        height="250"
        width="250">
</applet>
</body>
</html>

You can now load the applet in your browser or by using the appletviewer utility.

appletviewer.exe hello-world-applet.html
** Deprecated: The Applet API is deprecated since JDK 9, no replacement.

How do I get the available font family names?

package org.kodejava.awt;

import java.awt.GraphicsEnvironment;

public class FontFamilyNameList {
    public static void main(String[] args) {
        // Get all available font family names from GraphicsEnvironment
        GraphicsEnvironment ge = GraphicsEnvironment.getLocalGraphicsEnvironment();
        String[] familyNames = ge.getAvailableFontFamilyNames();

        // Iterates familyNames array to display the available font's family names
        for (String familyName : familyNames) {
            System.out.println("Family name: " + familyName);
        }
    }
}

Some font family names are shown below:

Family name: Agency FB
Family name: Algerian
Family name: Arial
Family name: Arial Black
Family name: Arial Narrow
Family name: Arial Rounded MT Bold
Family name: Bahnschrift
Family name: Baskerville Old Face
Family name: Bauhaus 93
Family name: Bell MT
...

How do I get the available font names?

package org.kodejava.awt;

import java.awt.Font;
import java.awt.GraphicsEnvironment;

public class FontNameList {
    public static void main(String[] args) {
        // Get all available fonts from GraphicsEnvironment
        GraphicsEnvironment ge = GraphicsEnvironment.getLocalGraphicsEnvironment();
        Font[] fonts = ge.getAllFonts();

        // Iterates all available fonts and get their name and family name
        for (Font font : fonts) {
            String fontName = font.getName();
            String familyName = font.getFamily();

            System.out.println("Font: " + fontName + "; family: " + familyName);
        }
    }
}

Here are some fonts name printed from the code snippet above:

Font: Agency FB; family: Agency FB
Font: Agency FB Bold; family: Agency FB
Font: Algerian; family: Algerian
Font: Arial; family: Arial
Font: Arial Black; family: Arial Black
Font: Arial Bold; family: Arial
Font: Arial Bold Italic; family: Arial
Font: Arial Italic; family: Arial
Font: Arial Narrow; family: Arial Narrow
Font: Arial Narrow Bold; family: Arial Narrow
...