### Question:
LoggerNameBuilder { public String buildByInvoker() { StackTraceElement invoker = resolveLoggerInvoker(); return build(invoker.getClassName(), invoker.getMethodName()); } private  LoggerNameBuilder(); static LoggerNameBuilder getInstance(); String build(MethodInvocation invocation); String build(Method method); String buildByInvoker();  }### Answer:
@Test public void buildByInvoker() { ManualLogger logger = new TestLogger(); logger.log(null, null); }
@Test(expected = IllegalArgumentException.class) public void buildByInvokerInvalid() { loggerNameBuilder.buildByInvoker(); }