아래 내용은
http://www.javabeat.net/tips/139-struts-10-vs-struts-20.html의 내용입니다.
Difference between Struts 1.0 and Struts 2.0
In the following section, we are going to compare the various features between the two frameworks.
Struts 2.0 is very simple as compared to struts 1.0,1.1, few of its excelent features are:
1.Servlet Dependency
Actions in Struts1 have dependencies on the servlet API since the
HttpServletRequest and HttpServletResponse objects are passed to the
execute method when an Action is invoked but in case of Struts 2.0, Actions are not container dependent because they are made simple POJOs. In Struts 2.0, the servlet contexts are represented as simple Maps which allows actions to be tested in isolation. Struts 2.0
Actions can access the original request and response, if required.
However, other architectural elements reduce or eliminate the need to
access the HttpServetRequest or HttpServletResponse directly.
2.Action classes
Programming the abstract classes instead of interfaces is one of
design issues of struts 1.0 framework that has been resolved in the Struts 2.0
framework. Struts 1.0 Action classes needs to extend framework
dependent abstract base class. But in case of Struts 2.0 Action class
may or may not implement interfaces to enable optional and custom
services. In case of Struts 2.0 , Actions are not container dependent because they are made simple POJOs. Struts 2.0
provides a base ActionSupport class to implement commonly used
interfaces. Albeit, the Action interface is not required. Any POJO
object with an execute signature can be used as an Struts 2.0 Action object.
3.Validation
Struts 1.0 and Struts 2.0 both supports the manual
validation via a validate method.
Struts 1.0 uses validate method on the ActionForm, or validates through
an extension to the Commons Validator. However, Struts 2.0 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.
4.Threading Model
In Struts1, Action resources must be thread-safe or synchronized. So
Actions are singletons and thread-safe, there should 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
1.0 Actions and requires extra care to develop. However in case of Struts 2.0,
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.)
5.Testability
Testing Struts 1.0 applications are a bit complex. A major hurdle to
test Struts 1.0 Actions is that the execute method because it exposes
the Servlet API. A third-party extension, Struts TestCase, offers a set
of mock object for Struts1. But the Struts 2.0
Actions can be tested by instantiating the Action, setting properties
and invoking methods. Dependency Injection support also makes testing
simpler. Actions in struts2 are simple POJOs and are framework
independent, hence testability is quite easy in struts2.
6.Harvesting Input
Struts 1.0 uses an ActionForm object to capture input. And all
ActionForms needs to extend a framework dependent base class. JavaBeans
cannot be used as ActionForms, so the developers have to create
redundant classes to capture input. However Struts 2.0 uses Action properties (as input
properties independent of underlying framework) that eliminates the
need for a second input object, hence reduces redundancy. Additionally
in Struts 2.0, Action properties can be accessed from the web page via the taglibs. Struts 2.0
also supports the ActionForm pattern, as well as POJO form objects and
POJO Actions. Even rich object types, including business or domain
objects, can be used as input/output objects.
7.Expression Language
Struts 1.0 integrates with JSTL, so it uses the JSTL-EL. The struts1 EL has basic object graph traversal, but relatively weak collection and indexed property support. Struts 2.0
can also use JSTL, however it supports a more powerful and flexible
expression language called "Object Graph Notation Language" (OGNL).
8.Binding values into views
In the view section, Struts1 uses the standard JSP mechanism to bind
objects (processed from the model section) into the page context to
access. However Struts 2.0
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 the reuse of views across a range of types
which may have the same property name but different property types.
9.Type Conversion
Usually, Struts 1.0 ActionForm properties are all Strings. Struts
1.0 uses Commons-Beanutils for type conversion. These type converters
are per-class and not configurable per instance. However Struts 2.0 uses OGNL for type conversion. The framework includes converters for basic and common object types and primitives.
10.Control Of Action Execution
Struts 1.0 supports separate Request Processor (lifecycles) for each
module, but all the Actions in a module must share the same lifecycle.
However Struts 2.0
supports creating different lifecycles on a per Action basis via
Interceptor Stacks. Custom stacks can be created and used with
different Actions as needed.
