简便的使用Log类，不用每次编码都写一堆判断是否空值、输出null还是""、拼接字符串等。
只需要在你主module的build.gradle文件中加入：
compile 'com.github.iveswang:jlog:1.0'
In the beginning,I want to use annotation processor+custom lint to make it more intelligent,
simplified the caller's parameters,but it's unable to get the variable's name passed on method,
also unable to get the length of a list during compile time, no way, had to use such a stupid plan.
本想用注解+lint来做得更智能一点，简化调用方的传参，但是无法取到传值的变量名，编译期也无法取到列表
的长度，没办法，只好用这么一个矬的方案了。
Copyright 2017 Ives Wang
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