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* KIND, either express or implied. See the License for the
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*
* This software consists of voluntary contributions made by many
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package org.apache.http.conn.routing;
import org.apache.http.annotation.Contract;
import org.apache.http.annotation.ThreadingBehavior;
import org.apache.http.util.Args;
Basic HttpRouteDirector implementation. Since: 4.0
/**
* Basic {@link HttpRouteDirector} implementation.
*
* @since 4.0
*/
@Contract(threading = ThreadingBehavior.IMMUTABLE)
public class BasicRouteDirector implements HttpRouteDirector {
Provides the next step.
Params: - plan – the planned route
- fact – the currently established route, or
null if nothing is established
Returns: one of the constants defined in this class, indicating
either the next step to perform, or success, or failure.
0 is for success, a negative value for failure.
/**
* Provides the next step.
*
* @param plan the planned route
* @param fact the currently established route, or
* {@code null} if nothing is established
*
* @return one of the constants defined in this class, indicating
* either the next step to perform, or success, or failure.
* 0 is for success, a negative value for failure.
*/
@Override
public int nextStep(final RouteInfo plan, final RouteInfo fact) {
Args.notNull(plan, "Planned route");
int step = UNREACHABLE;
if ((fact == null) || (fact.getHopCount() < 1)) {
step = firstStep(plan);
} else if (plan.getHopCount() > 1) {
step = proxiedStep(plan, fact);
} else {
step = directStep(plan, fact);
}
return step;
} // nextStep
Determines the first step to establish a route.
Params: - plan – the planned route
Returns: the first step
/**
* Determines the first step to establish a route.
*
* @param plan the planned route
*
* @return the first step
*/
protected int firstStep(final RouteInfo plan) {
return (plan.getHopCount() > 1) ?
CONNECT_PROXY : CONNECT_TARGET;
}
Determines the next step to establish a direct connection.
Params: - plan – the planned route
- fact – the currently established route
Returns: one of the constants defined in this class, indicating
either the next step to perform, or success, or failure
/**
* Determines the next step to establish a direct connection.
*
* @param plan the planned route
* @param fact the currently established route
*
* @return one of the constants defined in this class, indicating
* either the next step to perform, or success, or failure
*/
protected int directStep(final RouteInfo plan, final RouteInfo fact) {
if (fact.getHopCount() > 1) {
return UNREACHABLE;
}
if (!plan.getTargetHost().equals(fact.getTargetHost()))
{
return UNREACHABLE;
// If the security is too low, we could now suggest to layer
// a secure protocol on the direct connection. Layering on direct
// connections has not been supported in HttpClient 3.x, we don't
// consider it here until there is a real-life use case for it.
}
// Should we tolerate if security is better than planned?
// (plan.isSecure() && !fact.isSecure())
if (plan.isSecure() != fact.isSecure()) {
return UNREACHABLE;
}
// Local address has to match only if the plan specifies one.
if ((plan.getLocalAddress() != null) &&
!plan.getLocalAddress().equals(fact.getLocalAddress())
) {
return UNREACHABLE;
}
return COMPLETE;
}
Determines the next step to establish a connection via proxy.
Params: - plan – the planned route
- fact – the currently established route
Returns: one of the constants defined in this class, indicating
either the next step to perform, or success, or failure
/**
* Determines the next step to establish a connection via proxy.
*
* @param plan the planned route
* @param fact the currently established route
*
* @return one of the constants defined in this class, indicating
* either the next step to perform, or success, or failure
*/
protected int proxiedStep(final RouteInfo plan, final RouteInfo fact) {
if (fact.getHopCount() <= 1) {
return UNREACHABLE;
}
if (!plan.getTargetHost().equals(fact.getTargetHost())) {
return UNREACHABLE;
}
final int phc = plan.getHopCount();
final int fhc = fact.getHopCount();
if (phc < fhc) {
return UNREACHABLE;
}
for (int i=0; i<fhc-1; i++) {
if (!plan.getHopTarget(i).equals(fact.getHopTarget(i))) {
return UNREACHABLE;
}
}
// now we know that the target matches and proxies so far are the same
if (phc > fhc)
{
return TUNNEL_PROXY; // need to extend the proxy chain
}
// proxy chain and target are the same, check tunnelling and layering
if ((fact.isTunnelled() && !plan.isTunnelled()) ||
(fact.isLayered() && !plan.isLayered())) {
return UNREACHABLE;
}
if (plan.isTunnelled() && !fact.isTunnelled()) {
return TUNNEL_TARGET;
}
if (plan.isLayered() && !fact.isLayered()) {
return LAYER_PROTOCOL;
}
// tunnel and layering are the same, remains to check the security
// Should we tolerate if security is better than planned?
// (plan.isSecure() && !fact.isSecure())
if (plan.isSecure() != fact.isSecure()) {
return UNREACHABLE;
}
return COMPLETE;
}
}