Most clinical trials I see have a fixed sample size.  In some cases they have prior data that allows estimating the effect size and the variance or distribution of values, and calculate the sample size from that for a certain power.  In other cases it is just a guess.

Why wouldn't people run a clinical trial in which the sample size was determined during the trial?  (for example, by increasing it until the confidence interval narrowed to a certain size specified in advance)  Is there any reason this would not be a valid design?  Are there any examples of trials like that, and any references for designing a trial like that?


Question: How to load a properties file in java without calling laod method separately
Answer: Something along the lines of this:

class Test {
    Properties configFile = new Properties() {{ load(new FileInputStream("config.properties")); }};
}


You are actually sub classing Properties here and using its initialization section. 
load(..) might throw an Exception if so you would need to add a try { ... } catch () {}