STRUTS2 Interceptor Specific configuration process

Interceptors almost spread out in every program, so the specific interceptor configuration process, I hope to help everyone.

STRUTS2 Interceptor Specific configuration process

<interceptors>

<!--first define the interceptor--

<interceptor name= "Myinterceptor" class= "Com.zzz.struts2.interceptor.MyInterceptor" >

<!-- Specifies the number of parameters that the system initializes to the interceptor.

<param name= "Hello" > Zhang </param>

</interceptor>

<!-- added to your own set of interceptor stacks .

<interceptor-stack name= "Mystack" >

<interceptor-ref name= "Myinterceptor" >

</interceptor-ref>

<interceptor-ref name= "Defaultstack" ></interceptor-ref>

</interceptor-stack>

</interceptors>

<!-- Change the system's default interceptor to its own default interceptor , and a system can only have a default interceptor , This will apply the interceptor stack to all actions by default.

<default-interceptor-ref name= "Mystack" >

</default-interceptor-ref>

It is also possible to set a parameter to the interceptor when it is used : It is on the reslut of an action such as the following :

<action name= "register" class= "Com.zzz.struts2.action.RegisterAction" >

<result name= "Success" >/success.jsp</result>

<!--result It's another message forwarding type type= "" Remember, suppose you don't turn to the JSPand turn to the chart. Can change

Type= "" value -

<result name= "Input" >/register.jsp</result>

<interceptor-ref name= "Myinterceptor" >

<param name= "Hello" >welcome</param>

</interceptor-ref>

<interceptor-ref name= "Mystack" ></interceptor-ref>

</action>

2. The relationship between the Interceptor , the interceptor stack, and the default interceptor

1: interceptors and interceptors stack is a level , which means that an interceptor stack contains many interceptors , and an interceptor stack can contain many interceptor stacks , configuration such as the following methods :

<interceptors>

<!-- First define the Interceptor --

<interceptor name= "Myinterceptor" class= "Com.zzz.struts2.interceptor.MyInterceptor" >

<!-- Specifies the number of parameters that the system initializes to the interceptor.

<param name= "Hello" > Zhang </param>

</interceptor>

<!-- added to your own set of interceptor stacks .

<interceptor-stack name= "Mystack" >

<interceptor-ref name= "Myinterceptor" >

</interceptor-ref>

<interceptor-ref name= "Defaultstack" ></interceptor-ref>

</interceptor-stack>

</interceptors>

Use of interceptors : 1. Define First ; 2. in reference use ; 

<interceptor name= "Myinterceptor" class= "Com.zzz.struts2.interceptor.MyInterceptor" >

<interceptor-ref name= "Myinterceptor" >

</interceptor-ref>

2:struts2 has a system default interceptor stack is defaultstack, Assuming you manually reference your own interceptors , the system default interceptor stack will not work ; This requires manual introduction of the system's interceptor stack

<interceptor-ref name= "Defaultstack" > </interceptor-ref>

Suppose you want to change the default interceptor stack for the system, you can configure this :

<default-interceptor-ref name= "Mystack" > </default-interceptor-ref>

The mystack is a custom interceptor stack name ; Suppose there are multiple interceptors in the interceptor stack , in the Run Action the previous order is consistent with the order in which the interceptors are configured , and in Action then the order of the runs is reversed ; 

3: Abstract Interceptor class Abstractinterceptor

1:interceptor This Super Interceptor interface , There are three methods to implement , but assume that you do not want to use init (); and destroy ()

Method , the ability to inherit this abstract interceptor class ; its use is no different from the top. ;

4: method Filter Interceptor methodfilterinterceptor

1: The upper interceptor is for the entire action , Assuming that the interception of a method can inherit the class ;

Its use is almost the same as the usage above , just need to configure it to intercept the method , filter The Interceptor

Good do not configure yourself to set the default interceptor stack inside , You manually configure .

<interceptor-ref name= "MyInterceptor3" >

<param name= "Includemethods" >execute</param>

<param name= "Excludemethods" >execute</param>

</interceptor-ref>

<interceptor-ref name= "Defaultstack" ></interceptor-ref>

Among includemethods, Excludemethods is a fixed notation : Includemethods includes intercepting those methods ,  Multiple methods need to be separated by "," ; Excludemehtods is the method of excluding interception ;

5: listener preresultlistener interface

1: Its listening point after the interceptor has run through an action method , do something before rendering the view, and let a class implement the interface; Then register it with the interceptor that needs it. For example, the following code:

Publicclass MyInterceptor3 extends Methodfilterinterceptor {

Privatestaticfinallongserialversionuid = 3756655410194005443L;

@Override

Protected String dointercept (actioninvocation invocation) throws Exception {

//

Register the detector with the Interceptor ;

Invocation.addpreresultlistener (New MyListener ());

System.out.println ("My Interceptor3");

String Result=arg0.invoke ();

System.out.println ("My Interceptor3 finshed!");

return result;

}

}

STRUTS2 Interceptor Specific configuration process