core/src/main/java/org/springframework/security/access/vote/AbstractAclVoter.java
protected Object getDomainObjectInstance(MethodInvocation invocation) {
		Object[] args;
		Class<?>[] params;

		params = invocation.getMethod().getParameterTypes();
		args = invocation.getArguments();

		for (int i = 0; i < params.length; i++) {
			if (processDomainObjectClass.isAssignableFrom(params[i])) {
				return args[i];
			}
		}

		throw new AuthorizationServiceException("MethodInvocation: " + invocation
				+ " did not provide any argument of type: " + processDomainObjectClass);
	}
protected Object getDomainObjectInstance(MethodInvocation invocation) {
		Object[] args;
		Class<?>[] params;

		params = invocation.getMethod().getParameterTypes();
		args = invocation.getArguments();

		for (int i = 0; i < params.length; i++) {
			if (processDomainObjectClass.isAssignableFrom(params[i])) {
				return args[i];
			}
		}

		throw new AuthorizationServiceException("MethodInvocation: " + invocation
				+ " did not provide any argument of type: " + processDomainObjectClass);
	}
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