2.2.1 Core Container
The Core Container consists of the spring-core, spring-beans, spring-context, spring-context-support, and spring-expression (Spring Expression Language) modules.
The spring-core and spring-beans modules provide the fundamental parts of the framework, including the IoC and Dependency Injection features. TheBeanFactory is a sophisticated implementation of the factory pattern. It removes the need for programmatic singletons and allows you to decouple the configuration and specification of dependencies from your actual program logic.
核心容器由spring-core，spring-beans，spring-context，spring-context-support和spring-expression（Spring Expression Language）模块组成。
spring-core和spring-beans模块提供了框架的基本部分，包括IoC和依赖注入功能。 BeanFactory是一个复杂的工厂模式的实现。 它消除了编程单例的需要(程序员不必对单例亲力亲为)，并允许你从实际的程序逻辑中分离依赖性的配置和规范。
The Context (spring-context) module builds on the solid base provided by the Core and Beans modules: it is a means to access objects in a framework-style manner that is similar to a JNDI registry. The Context module inherits its features from the Beans module and adds support for internationalization (using, for example, resource bundles), event propagation, resource loading, and the transparent creation of contexts by, for example, a Servlet container. The Context module also supports Java EE features such as EJB, JMX, and basic remoting. The ApplicationContext interface is the focal point of the Context module. spring-context-support provides support for integrating common third-party libraries into a Spring application context, in particular for caching (EhCache, JCache) and scheduling (CommonJ, Quartz).
Context（spring-context）模块建立在Core和Beans模块提供的实体基础之上：它是一种以类似于JNDI注册表的框架样式方式访问对象的手段。 Context模块从Beans模块继承其特性，并增加了对国际化（例如使用资源束），事件传播，资源加载以及通过例如Servlet容器的透明创建上下文的支持。 Context模块还支持Java EE功能，如EJB，JMX和基本远程处理。ApplicationContext接口是Context模块的焦点。spring-context-support提供支持将常见的第三方库集成到Spring应用程序上下文中，特别是用于缓存（EhCache，JCache）和定时任务等（CommonJ，Quartz）。
The spring-expression module provides a powerful Expression Language for querying and manipulating an object graph at runtime. It is an extension of the unified expression language (unified EL) as specified in the JSP 2.1 specification. The language supports setting and getting property values, property assignment, method invocation, accessing the content of arrays, collections and indexers, logical and arithmetic operators, named variables, and retrieval of objects by name from Spring’s IoC container. It also supports list projection and selection as well as common list aggregations.
spring-expression模块提供了一个强大的表达式语言，用于在运行时查询和操作对象图。 它是JSP 2.1规范中规定的统一表达式语言（统一EL）的扩展。 该语言支持设置和获取属性值，属性赋值，方法调用，访问数组的内容，集合和索引器，逻辑和算术运算符，命名变量，以及通过Spring IoC容器中的名称检索对象。 它还支持列表投影和选择以及公共列表聚合。