/*
* Copyright 2014 JBoss Inc
*
* Licensed 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.apiman.gateway.engine.policy;
import io.apiman.gateway.engine.beans.ApiRequest;
import io.apiman.gateway.engine.io.IReadWriteStream;
import java.util.Iterator;
import java.util.List;
/**
* Request phase policy chain.
*
* @author Marc Savy <msavy@redhat.com>
*/
public class RequestChain extends Chain<ApiRequest> {
/**
* Constructor.
* @param policies the policies
* @param context the context
*/
public RequestChain(List<PolicyWithConfiguration> policies, IPolicyContext context) {
super(policies, context);
}
/**
* @see java.lang.Iterable#iterator()
*/
@Override
public Iterator<PolicyWithConfiguration> iterator() {
return new RequestPolicyIterator(getPolicies());
}
/**
* @see io.apiman.gateway.engine.policy.Chain#getApiHandler(io.apiman.gateway.engine.policy.IPolicy, java.lang.Object)
*/
@Override
protected IReadWriteStream<ApiRequest> getApiHandler(IPolicy policy, Object config) {
if (policy instanceof IDataPolicy) {
return ((IDataPolicy) policy).getRequestDataHandler(getHead(), getContext(), config);
} else {
return null;
}
}
/**
* @see io.apiman.gateway.engine.policy.Chain#applyPolicy(io.apiman.gateway.engine.policy.PolicyWithConfiguration, io.apiman.gateway.engine.policy.IPolicyContext)
*/
@Override
protected void applyPolicy(PolicyWithConfiguration policy, IPolicyContext context) {
ClassLoader oldCtxLoader = Thread.currentThread().getContextClassLoader();
try {
Thread.currentThread().setContextClassLoader(policy.getPolicy().getClass().getClassLoader());
policy.getPolicy().apply(getHead(), context, policy.getConfiguration(), this);
} finally {
Thread.currentThread().setContextClassLoader(oldCtxLoader);
}
}
/**
* An iterator over a list of policies - iterates through the policies from
* front to back, which is the proper order when applying the policies to
* the inbound request.
*/
private class RequestPolicyIterator implements Iterator<PolicyWithConfiguration> {
private List<PolicyWithConfiguration> policies;
private int index;
/**
* Constructor.
* @param policies list of configured policies
*/
public RequestPolicyIterator(List<PolicyWithConfiguration> policies) {
this.policies = policies;
this.index = 0;
}
/**
* @see java.util.Iterator#remove()
*/
@Override
public void remove() {
throw new UnsupportedOperationException();
}
/**
* @see java.util.Iterator#next()
*/
@Override
public PolicyWithConfiguration next() {
return policies.get(index++);
}
/**
* @see java.util.Iterator#hasNext()
*/
@Override
public boolean hasNext() {
return index < policies.size();
}
};
}