青草青永久在线手机版

One problem with the factory method pattern is that the creation of the class depends on the factory class, that is to say, if you want to expand the program, you must modify the factory class, which violates the closure principle. Therefore, from the design point of view, there are certain problems, how to solve them? We use the abstract factory mode to create multiple factory classes, so that once new functions need to be added, we can directly add new factory classes without modifying the previous code. Because the abstract factory is not very easy to understand, let's look at the diagram first, and then it is easier to understand with the code.For patent medicineIn programming, Sometimes it is necessary to generate a large number of fine-grained class instances to represent data. If we can find that these instances are basically the same except for a few parameters, if we can move those parameters outside the class instances and pass them in when the method is called, we can greatly reduce the number of individual instances by sharing the website invariant稍后的遭遇让他们清楚地体会到福无双至，祸不单行的这句俗语是多么的有道理。新书求收藏求推荐。电视剧《海棠依 旧》真实展现了周恩来总理从1949年 初入驻中南海西华厅到1976年1月去 世,近27年间的工作与生活的真实感人 故事，以召开新政治协商会议、开国 大典、派遣驻外大使、抗美援朝、万 隆会议、邢台抗震救灾、中美建交等 国内外一系列重大历史事件为背景， 表现周恩来总理勤政为民的大国总理 风范和高尚的人格魅力。