Tomcat filter Simulation

Directly use the code filter. Java

Public interface filter {// filter public void dofilter (request, response, filterchain chain );}

Filterchain. Java

Public class filterchain {// store all the filters private list <filter> filters; // record the Current Filter index private int index; // The filter chain initializes public filterchain () {filters = new arraylist <filter> (10);} public void addfilter (filter) {filters. add (filter);}/*** iterative filtering */Public void dofilter (request, response) {If (index> = filters. size () return; filters. get (index ++ ). dofilter (request, response, this );}}

Request. Java

public class Request {        private String value;    public String getValue() {        return value;    }    public void setValue(String value) {        this.value = value;    }        @Override    public String toString() {        return this.value;    }}

Response. Java

public class Response {        private String value;    public String getValue() {        return value;    }    public void setValue(String value) {        this.value = value;    }        @Override    public String toString() {        return this.value;    }}

Filterone. Java

Public class filterone implements filter {/*** filter the fuck character */@ override public void dofilter (request, response, filterchain chain) {system. out. println ("go to the filter filterone -------------------------------------"); // execute the next filter chain. dofilter (request, response); system. out. println ("out Filter filterone ---------------------------------------");}}

Filtertwo. Java

Public class filtertwo implements filter {@ override public void dofilter (request, response, filterchain chain) {system. out. println ("go to the filter filtertwo -------------------------------------"); // execute the next filter chain. dofilter (request, response); system. out. println ("out Filter filtertwo ---------------------------------------");}}

Test. Java

public class Test {        public static void main(String[] args) {        FilterChain chain = new FilterChain();        chain.addFilter(new FilterOne());        chain.addFilter(new FilterTwo());        chain.doFilter(new Request(), new Response() );    }}

Running result

Go to the filter filterone plugin and enter the filter filtertwo plugin. Go out of the filter filtertwo ------------------------------- go out of the filter filterone ---------------------------------------

 

Tomcat filter Simulation