Comments on: Overiding Singletons For Testing http://blog.james-carr.org/2007/07/07/overiding-singletons-for-testing/ Rants and Musings of an Agile Developer Sat, 22 Nov 2008 07:09:33 +0000 http://wordpress.org/?v=2.6.1 By: ScreenCast! : 0xDEADBEEFCAFE http://blog.james-carr.org/2007/07/07/overiding-singletons-for-testing/#comment-25534 ScreenCast! : 0xDEADBEEFCAFE Sun, 08 Jul 2007 08:08:22 +0000 http://blog.james-carr.org/?p=86#comment-25534 [...] Heh, mute the audio and check out my first webcast! This is an experiment, and I don’t show anything groundbraking, in fact I just recode the problem from James Carr blog. I just wanted to show one usefull pattern in action. [...] [...] Heh, mute the audio and check out my first webcast! This is an experiment, and I don’t show anything groundbraking, in fact I just recode the problem from James Carr blog. I just wanted to show one usefull pattern in action. [...]

]]> By: Mark Derricutt http://blog.james-carr.org/2007/07/07/overiding-singletons-for-testing/#comment-25445 Mark Derricutt Sat, 07 Jul 2007 06:08:38 +0000 http://blog.james-carr.org/?p=86#comment-25445 I was doing something very similar last week to get some tests working. I ended up actually using a ThreadLocal singleton with a private setter rather than an a subclass. The tests pass in an anonymous inner implementation specific to the test at hand via a simple helper method: final String[] reminderSmsMessage = new String[1]; BindUtils.bindSmsSender(new SendSMS() { public void sendSms(String to, UserVo userVo, String message, String messageId, String rateCode) { reminderSmsMessage[0] = message; } }); From here I do something and can track the results of the message send. bindSmsSender() sinply does: Method method = SendSMS.class.getDeclaredMethod("bind", SendSMS.class); method.setAccessible(true); method.invoke(null, sendSMS); I was doing something very similar last week to get some tests working. I ended up actually using a ThreadLocal singleton with a private setter rather than an a subclass.

The tests pass in an anonymous inner implementation specific to the test at hand via a simple helper method:

final String[] reminderSmsMessage = new String[1];
BindUtils.bindSmsSender(new SendSMS() {
public void sendSms(String to, UserVo userVo, String message, String messageId, String rateCode) {
reminderSmsMessage[0] = message;
}
});

From here I do something and can track the results of the message send.

bindSmsSender() sinply does:

Method method = SendSMS.class.getDeclaredMethod(”bind”, SendSMS.class);
method.setAccessible(true);
method.invoke(null, sendSMS);

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