src/org/nutz/lang/util/NutMap.java
@Override
    @SuppressWarnings("unchecked")
    public <T> T getOrBorn(String key, Borning<T> factory) {
        T t = (T) get(key);
        if (t == null) {
            t = factory.born(key);
            put(key, t);
        }
        return t;
    }
@Override
    @SuppressWarnings("unchecked")
    public <T> T getOrBorn(String key, Borning<T> factory) {
        T t = (T) get(key);
        if (t == null) {
            t = factory.born(key);
            put(key, t);
        }
        return t;
    }
获取对应的值,若不存在,用factory创建一个,然后设置进去,返回之

@param key
键
@param factory
若不存在的话用于生成实例
@return 已存在的值或新的值