brxonline
- 浏览: 64270 次
- 性别:
- 来自: 苏州
-
最新评论
-
brxonline：
提示不能这样写234390216 写道234390216 写道 ...
mysql导出数据为excel -
234390216：
234390216 写道不行啊，错误
提示不能这样写
mysql导出数据为excel -
234390216：
不行啊，错误
mysql导出数据为excel
文章列表
Without violating encapsulation, capture and externalize an object's internal state so that the object can be restored to this state later.
Define an object that encapsulates how a set of objects interact. Mediator promotes loose coupling by keeping objects from referring to each other explicitly, and it lets you vary their interaction independently.
Provide a way to access the elements of an aggregate object sequentially without exposing its underlying representation.
Given a language, define a representation for its grammar along with an interpreter that uses the representation to interpret sentences in the language.
Encapsulate a request as an object, thereby letting you parameterize clients with different requests, queue or log requests, and support undoable operations.
Avoid coupling the sender of a request to its receiver by giving more than one object a chance to handle the request. Chain the receiving objects and pass the request along the chain until an object handles it.
Attach additional responsibilities to an object dynamically. Decorators provide a flexible alternative to subclassing for extending functionality
Compose objects into tree structures to represent part-whole hierarchies. Composite lets clients treat individual objects and compositions of objects uniformly.
Decouple an abstraction from its implementation so that the two can vary independently.
Convert the interface of a class into another interface clients expect. Adapter lets classes work together that couldn't otherwise because of incompatible interfaces
Ensure a class has only one instance and provide a global point of access to it.
定义：提供一个创建一系列相关或相互依赖对象的接口，而无需指定他们的具体类。（Provide an interface for creating families of related or dependent objects without specifying their concrete classes. ）
1、Java有没有goto
答：java中的保留字，现在没有在java中使用
2、Overload和Override的区别。Overloaded的方法是否可以改变返回值的类型
答：方法的重写Overriding和重载Overloading是Java多态性的不同表现。重写Overriding是父类与子类之间多态性的一种表现，重载Overloading是一个类中多态性的一种表现。如果在子类中定义某方法与其父类有相同的名称和参数，我们说该方法被重写 (Overriding)。子类的对象使用这个方法时，将调用子类中的定义，对它而言，父类中的定义如同被"屏蔽"了。如果在一个类中定义了多 ...
- 2008-07-06 16:12
- 浏览 939
- 评论(0)
By Jim Stevenson
Elmont, NY
07 June 2008
Kentucky Derby and Preakness winner Big Brown runs Saturday in New York in his bid to become horse racing's first so-called Triple Crown winner in 30 years. As VOA's Jim Stevenson reports from Belmont Park, final preparations have been made for the bi ...
- 2008-06-09 15:12
- 浏览 744
- 评论(0)