/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing,
* software distributed under the License is distributed on an
* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
* KIND, either express or implied. See the License for the
* specific language governing permissions and limitations
* under the License.
*/
package io.milton.mail;
import java.util.List;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/** Passes the request and response along a series of filters
*
* By default the MailServer loads a single filter which executes the appropriate
* handler for the http method
*
* Additional filters can be added using HttpManager.addFilter
*/
public class FilterChain {
private final static Logger log = LoggerFactory.getLogger(FilterChain.class);
final List<Filter> filters;
final Filter terminal;
int pos = 0;
public FilterChain(List<Filter> filters, Filter terminal) {
this.filters = filters;
this.terminal = terminal;
}
public void doEvent(Event event) {
if( pos < filters.size() ) {
Filter filter = filters.get(pos++);
if( filter != null ) {
filter.doEvent(this,event);
return ;
}
log.warn( "Configuration problem. null filter at position: " + pos);
}
if( terminal != null ) {
terminal.doEvent(this, event);
} else {
log.warn("there appears to be no filters to process the request! Should be at least a terminal filter");
}
}
}