/**
* Instantiate an object by calling one of its constructors.
*
* @param objectInitInfo a string description of the object to instantiate. The objectInitInfo is
* expected to have one of the following forms:
* <ol>
* <li>my.cool.Stuff
* <li>my.cool.Stuff(any,string,args,without,spaces)
* <li>my.cool.Stuff(arguments,$my.special.property,other,args)
* </ol>
* where 'my.special.property' is a property in one of the MARY config files.
* @return the newly instantiated object.
* @throws ClassNotFoundException
* @throws IllegalArgumentException
* @throws InstantiationException
* @throws IllegalAccessException
* @throws InvocationTargetException
* @throws SecurityException
* @throws NoSuchMethodException
*/
public static Object instantiateObject(String objectInitInfo) throws MaryConfigurationException {
Object obj = null;
String[] args = null;
String className = null;
try {
if (objectInitInfo.contains("(")) { // arguments
int firstOpenBracket = objectInitInfo.indexOf('(');
className = objectInitInfo.substring(0, firstOpenBracket);
int lastCloseBracket = objectInitInfo.lastIndexOf(')');
args = objectInitInfo.substring(firstOpenBracket + 1, lastCloseBracket).split(",");
for (int i = 0; i < args.length; i++) {
if (args[i].startsWith("$")) {
// replace value with content of property named after the $
args[i] = MaryProperties.getProperty(args[i].substring(1));
}
args[i] = args[i].trim();
}
} else { // no arguments
className = objectInitInfo;
}
Class<? extends Object> theClass = Class.forName(className).asSubclass(Object.class);
// Now invoke Constructor with args.length String arguments
if (args != null) {
Class<String>[] constructorArgTypes = new Class[args.length];
Object[] constructorArgs = new Object[args.length];
for (int i = 0; i < args.length; i++) {
constructorArgTypes[i] = String.class;
constructorArgs[i] = args[i];
}
Constructor<? extends Object> constructor =
(Constructor<? extends Object>) theClass.getConstructor(constructorArgTypes);
obj = constructor.newInstance(constructorArgs);
} else {
obj = theClass.newInstance();
}
} catch (Exception e) {
// try to make e's message more informative if possible
throw new MaryConfigurationException(
"Cannot instantiate object from '"
+ objectInitInfo
+ "': "
+ MaryUtils.getFirstMeaningfulMessage(e),
e);
}
return obj;
}
