Mule custom filter with a prototype filter

README.md

This gist shows a simple way to create a Mule custom filter which are prototype Spring beans.

FilterProxy.java

import org.mule.api.MuleMessage;
import org.mule.api.routing.filter.Filter;
import org.springframework.beans.BeansException;
import org.springframework.context.ApplicationContext;
import org.springframework.context.ApplicationContextAware;


public class FilterProxy implements Filter, ApplicationContextAware {
	private ApplicationContext context;
	private String realFilterId;

	@Override
	public boolean accept(MuleMessage message) {
		Filter filter = (Filter) context.getBean(realFilterId, Filter.class);
		return filter.accept(message);
	}
	
	public void setRealFilterId(String realFilterId) {
		this.realFilterId = realFilterId;
	}

	@Override
	public void setApplicationContext(ApplicationContext context)
			throws BeansException {
		this.context = context;
		
	}

}

MyFilter.java

import java.util.Random;

import org.apache.log4j.Logger;
import org.mule.api.MuleMessage;
import org.mule.api.routing.filter.Filter;


public class MyFilter implements Filter {
	private int randomNumber;
	Logger log = Logger.getLogger(MyFilter.class);
	
	public MyFilter() {
		Random random = new Random();
		randomNumber = random.nextInt(100);
	}
	
	@Override
	public boolean accept(MuleMessage message) {
		log.info(this + " has number " + randomNumber);
		return (randomNumber >= 50);
	}
}

simplefilter.xml

<?xml version="1.0" encoding="UTF-8"?>

<mule xmlns:http="http://www.mulesoft.org/schema/mule/http" xmlns="http://www.mulesoft.org/schema/mule/core" xmlns:doc="http://www.mulesoft.org/schema/mule/documentation"
	xmlns:spring="http://www.springframework.org/schema/beans" version="EE-3.5.0"
	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
	xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-current.xsd
http://www.mulesoft.org/schema/mule/core http://www.mulesoft.org/schema/mule/core/current/mule.xsd
http://www.mulesoft.org/schema/mule/http http://www.mulesoft.org/schema/mule/http/current/mule-http.xsd">

	<spring:bean id="realFilter" class="MyFilter" scope="prototype"/>
	
    <flow name="simplefilterFlow1" doc:name="simplefilterFlow1">
        <http:inbound-endpoint exchange-pattern="request-response" host="localhost" port="8081" doc:name="HTTP"/>
        <custom-filter class="FilterProxy" doc:name="Custom">
        	<spring:property name="realFilterId" value="realFilter"/>
        </custom-filter>
        <set-payload value="Passed filter" doc:name="Set Payload"/>
    </flow>
</mule>