How do I find the BlackBerry OS version?

The user of a BlackBerry wireless handheld can find the operating system (OS) version by selecting Applications from the Options application. You'll end up with a screen like this:

In this example, the device is running version 3.7 of the operating system.

Programmatically, the easiest way to get the version number is to obtain the version string for the net_rim_bb_browser_daemon module:

import net.rim.device.api.system.CodeModuleManager;

int handle = CodeModuleManager.getModuleHandle( "net_rim_bb_browser_daemon" );
if( handle != 0 ){
    String version = CodeModuleManager.getModuleVersion( handle );
}

The version string will be in the "A.B.C.D" format, for example "3.7.0.58". Looking for a specific version is just a matter of using the startsWith method:

public String is37( String version ){
    return version.startsWith( "3.7." );
}

A more comprehensive approach is convert each part of the string into an integer:

/**
 * Returns the version information as an int array, with
 * index 0 being the leftmost version number (the major
 * OS version) and index 3 being the rightmost version number
 * (the build number). For example:
 * <pre>
 * int[] version = getVersion();
 * if( ( version[0] == 3 && version[1] >= 8 ) ||
 *     version[0] >= 4 ){
 *     // this is version 3.8 or higher
 * }
 * </pre>
 */

public int[] getVersion(){
    int[] ret = new int[4]{ 3, 6, 0, 0 }; // def to 3.6
    int   h = CodeModuleManager.getModuleHandle( "net_rim_bb_browser_daemon" );

    if( h == 0 ) return ret;

    String v = CodeModuleManager.getModuleVersion( h );

    int p1 = v.indexOf( '.' );
    int p2 = v.indexOf( '.', p1+1 );
    int p3 = v.indexOf( '.', p2+2 );

    try {
	ret[0] = Integer.parseInt( v.substring( 0, p1 ) );
	ret[1] = Integer.parseInt( v.substring( p1+1, p2 ) );
	ret[2] = Integer.parseInt( v.substring( p2+1, p3 ) );
	ret[3] = Integer.parseInt( v.substring( p3+1 ) );
    }
    catch( NumberFormatException e ){
	// ignore it
    }

    return ret;
}

Note that the BlackBerry platform number is different than the OS version, so DeviceInfo.getOSVersion() returns a different number than the code shown above.