Spring wiring private init-method

While adding some unit tests to older Spring code, I noticed that the production Spring configuration was wiring together some pretty simple Factory objects that had private init() methods (took a few minutes to figure out why I kept getting wavy lines), that looked like this:

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private void init(){
try {
StringBuilder sb = new StringBuilder();
for(String server : servers){
sb.append(server.trim());
sb.append(BLANK_SPACE_DELIMITER);
}

memCacheClient = new MemcachedClient(AddrUtil.getAddresses(sb.toString()));
} catch (IOException e) {
log.error("Unable to Connect to memCache " ,e);
throw new RuntimeException("Unable to Connect to memCache " , e);
}
}

It turns out thatÂ AbstractAutowireCapableBeanFactory does a bit of reflection when processing ‘init-method’ to allow it to invoke private methods (assuming you don’t have any SecurityMangers running, which you probably don’t)

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ReflectionUtils.makeAccessible(initMethod);
try {
initMethod.invoke(bean, (Object[]) null);
}

So… magic…

Jason E. Shao

Spring wiring private init-method