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So sánh Struts 1 và Struts 2

Feature

Struts 1

Struts 2

Action classes

Struts 1 requires Action classes to extend an abstract base class. A common problem in Struts 1 is programming to abstract classes instead of interfaces.

An Struts 2 Action may implement an Action interface, along with other interfaces to enable optional and custom services. Struts 2 provides a base ActionSupport class to implement commonly used interfaces. Albeit, the Action interface is not required. Any POJO object with a execute signature can be used as an Struts 2 Action object.

Threading Model

Struts 1 Actions are singletons and must be thread-safe since there will only be one instance of a class to handle all requests for that Action. The singleton strategy places restrictions on what can be done with Struts 1 Actions and requires extra care to develop. Action resources must be thread-safe or synchronized.

Struts 2 Action objects are instantiated for each request, so there are no thread-safety issues. (In practice, servlet containers generate many throw-away objects per request, and one more object does not impose a performance penalty or impact garbage collection.)

Servlet Dependency

Struts 1 Actions have dependencies on the servlet API since the HttpServletRequest and HttpServletResponse is passed to the execute method when an Action is invoked.

Struts 2 Actions are not coupled to a container. Most often the servlet contexts are represented as simple Maps, allowing Actions to be tested in isolation. Struts 2 Actions can still access the original request and response, if required. However, other architectural elements reduce or eliminate the need to access the HttpServetRequest or HttpServletResponse directly.

Testability

A major hurdle to testing Struts 1 Actions is that the execute method exposes the Servlet API. A third-party extension, Struts TestCase, offers a set of mock object for Struts 1.

Struts 2 Actions can be tested by instantiating the Action, setting properties, and invoking methods. Dependency Injection support also makes testing simpler.

Harvesting Input

Struts 1 uses an ActionForm object to capture input. Like Actions, all ActionForms must extend a base class. Since  other JavaBeans cannot be used as ActionForms, developers often create redundant classes to capture input. DynaBeans can used as an alternative to creating conventional ActionForm classes, but, here too, developers may be redescribing existing JavaBeans.

Struts 2 uses Action properties as input properties, eliminating the need for a second input object. Input properties may be rich object types which may have their own properties. The Action properties can be accessed from the web page via the taglibs. Struts 2 also supports the ActionForm pattern, as well as POJO form objects and POJO Actions. Rich object types, including business or domain objects, can be used as input/output objects. The ModelDriven feature simplifies taglb references to POJO input objects.

Expression Language

Struts 1 integrates with JSTL, so it uses the JSTL EL. The EL has basic object graph traversal, but relatively weak collection and indexed property support.

Struts 2 can use JSTL, but the framework also supports a more powerful and flexible expression language called “Object Graph Notation Language” (OGNL).

Binding values into views

Struts 1 uses the standard JSP mechanism for binding objects into the page context for access.

Struts 2 uses a “ValueStack” technology so that the taglibs can access values without coupling your view to the object type it is rendering. The ValueStack strategy allows reuse of views across a range of types which may have the same property name but different property types.

Type Conversion

Struts 1 ActionForm properties are usually all Strings. Struts 1 uses Commons-Beanutils for type conversion. Converters are per-class, and not configurable per instance.

Struts 2 uses OGNL for type conversion. The framework includes converters for basic and common object types and primitives.

Validation

Struts 1 supports manual validation via a validate method on the ActionForm, or through an extension to the Commons Validator. Classes can have different validation contexts for the same class, but cannot chain to validations on sub-objects.

Struts 2 supports manual validation via the validate method and the XWork Validation framework. The Xwork Validation Framework supports chaining validation into sub-properties using the validations defined for the properties class type and the validation context.

Control Of Action Execution

Struts 1 supports separate Request Processors (lifecycles) for each module, but all the Actions in the module must share the same lifecycle.

Struts 2 supports creating different lifecycles on a per Action basis via Interceptor Stacks. Custom stacks can be created and used with different Actions, as needed.

6 Responses to “So sánh Struts 1 và Struts 2”

  1. Thảo Phương said

    Chào bạn!
    Mình tìm các bài so sánh giữa Struts 1 và Struts 2 để lựa chọn. Mình đang rất phân vân, không biết lựa chọn cái nào. Theo mình đọc thì thấy Struts 2 có những ưu điểm hơn hẳn Struts 1, nhưng lại nghe nhiều người than phiền Struts 2 không ổn định. Và mình cũng ko rõ là thực tế người ta dùng phiên bản nào nhiều hơn. Mình chỉ mới biết qua Struts (sơ qua cả 2 version).
    Mình rất vui khi bạn cho mình lời khuyên để lựa chọn.
    Cảm ơn bạn trước nhé!

  2. vovanhai said

    Nên dùng struts 2. Đó là sự khôn ngoan khi phải lựa chọn giữa 2 version. Ngoài ra, bay giờ struts cũng không còn là lựa chọn số 1 như ngày xưa. bạn có thể tham khảo rất nhiều framework khác như richfaces, spring,…

  3. Thảo Phương said

    Cảm ơn bạn nhé!

  4. Struts 2 co uu diem la su dung nhieu Annotation, bot di ruom ra XML va cau hinh.

    Tuy nhien Spring (2.5+) van hay hon nhieu so voi Struts 2

  5. hieutiny said

    Chao thay!thay co the cho e sach nao viet ve van de struts2 duoc k ah.e dang can de tham khao la mot so van de

  6. vovanhai said

    Đây là cuốn Struts2 in action, bạn download về nhé. (nhớ đường có nhấn phải chọn save-as mà đi theo link)
    Download this book

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