Java and Electronic Mail - Java - page 684

Further, I break the email address into two parts and provide the @ separately, so it won't be
seen as an email address even if the spam-spider is clever enough to look into the param
parts of the applet tag. Because I know you won't actually deploy this code without chan-
ging Target1 and Target2 —the param tags for the mail receiver's email name and host do-
main—you're fairly safe from spam with this. Example 17-1 is the Java applet class.

Example 17-1. MailtoButton.java
public public class class MailtoButton MailtoButton extends extends Applet {

private private static long serialVersionUID = - 3186706180199804315L ;

/** The label that is to appear in the button */
protected

static final final long

protected String label = null null ;

/** The width and height */
protected protected int int width , height ;

/** The string form of the URL to jump to */
protected protected String targetName , targetHost ;

/** The URL to jump to when the button is pushed. */
protected

protected URL targetURL ;
/** The name of the font */
protected protected String fontName ;

protected

protected String DEFAULTFONTNAME = "helvetica" ;
/** The font */
protected protected Font theFont ;

/** The size of the font */
protected protected int int fontSize = 18 ;

/** The HTML PARAM for the user account -- keep it short */
private

private String TARGET1 = "U" ; // for User
/** The HTML PARAM for the hostname -- keep it short */
private private String TARGET2 = "H" ; // for Host

// Dummy
//private String BOGON1 = "username"; // happy strings-ing, SPAM perps
//private String BOGON2 = "hostname"; // ditto.
/** The string for the Subject line, if any */
private private String subject ;

/** Called from the browser to set up. We want to throw various
* kinds of exceptions but the API predefines that we don't, so we
* limit ourselves to the ubiquitous IllegalArgumentException.
*/
public

public void void init () {

// System.out.println("In LinkButton::init");
try try {

iif (( targetName = getParameter ( TARGET1 )) == null null )

throw throw new new IllegalArgumentException (