1-static factory - Effective Java 3rd version [学习笔记]

static factory 优点:

1. have meaningful name;
2. not required to create new object each time

-- Singleton;
-- Cache object;
-- Return object based on parameters;

3. return sub-class, not current class;
4. returned object can vary from call to call, release to release;

缺点:
难找.

可以用 .from, .of, .valueOf, .instance, .getInstance, .create, .newInstance, .getType, .type, .newType.