/*
* ====================================================================
* 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.
* ====================================================================
*
* This software consists of voluntary contributions made by many
* individuals on behalf of the Apache Software Foundation. For more
* information on the Apache Software Foundation, please see
* <http://www.apache.org/>.
*
*/
package org.apache.http.conn.routing;
import java.net.InetAddress;
import org.apache.http.HttpHost;
import org.apache.http.annotation.NotThreadSafe;
import org.apache.http.util.Args;
import org.apache.http.util.Asserts;
import org.apache.http.util.LangUtils;
/**
* Helps tracking the steps in establishing a route.
*
* @since 4.0
*/
@NotThreadSafe
public final class RouteTracker implements RouteInfo, Cloneable {
/** The target host to connect to. */
private final HttpHost targetHost;
/**
* The local address to connect from.
* {@code null} indicates that the default should be used.
*/
private final InetAddress localAddress;
// the attributes above are fixed at construction time
// now follow attributes that indicate the established route
/** Whether the first hop of the route is established. */
private boolean connected;
/** The proxy chain, if any. */
private HttpHost[] proxyChain;
/** Whether the the route is tunnelled end-to-end through proxies. */
private TunnelType tunnelled;
/** Whether the route is layered over a tunnel. */
private LayerType layered;
/** Whether the route is secure. */
private boolean secure;
/**
* Creates a new route tracker.
* The target and origin need to be specified at creation time.
*
* @param target the host to which to route
* @param local the local address to route from, or
* {@code null} for the default
*/
public RouteTracker(final HttpHost target, final InetAddress local) {
Args.notNull(target, "Target host");
this.targetHost = target;
this.localAddress = local;
this.tunnelled = TunnelType.PLAIN;
this.layered = LayerType.PLAIN;
}
/**
* @since 4.2
*/
public void reset() {
this.connected = false;
this.proxyChain = null;
this.tunnelled = TunnelType.PLAIN;
this.layered = LayerType.PLAIN;
this.secure = false;
}
/**
* Creates a new tracker for the given route.
* Only target and origin are taken from the route,
* everything else remains to be tracked.
*
* @param route the route to track
*/
public RouteTracker(final HttpRoute route) {
this(route.getTargetHost(), route.getLocalAddress());
}
/**
* Tracks connecting to the target.
*
* @param secure {@code true} if the route is secure,
* {@code false} otherwise
*/
public final void connectTarget(final boolean secure) {
Asserts.check(!this.connected, "Already connected");
this.connected = true;
this.secure = secure;
}
/**
* Tracks connecting to the first proxy.
*
* @param proxy the proxy connected to
* @param secure {@code true} if the route is secure,
* {@code false} otherwise
*/
public final void connectProxy(final HttpHost proxy, final boolean secure) {
Args.notNull(proxy, "Proxy host");
Asserts.check(!this.connected, "Already connected");
this.connected = true;
this.proxyChain = new HttpHost[]{ proxy };
this.secure = secure;
}
/**
* Tracks tunnelling to the target.
*
* @param secure {@code true} if the route is secure,
* {@code false} otherwise
*/
public final void tunnelTarget(final boolean secure) {
Asserts.check(this.connected, "No tunnel unless connected");
Asserts.notNull(this.proxyChain, "No tunnel without proxy");
this.tunnelled = TunnelType.TUNNELLED;
this.secure = secure;
}
/**
* Tracks tunnelling to a proxy in a proxy chain.
* This will extend the tracked proxy chain, but it does not mark
* the route as tunnelled. Only end-to-end tunnels are considered there.
*
* @param proxy the proxy tunnelled to
* @param secure {@code true} if the route is secure,
* {@code false} otherwise
*/
public final void tunnelProxy(final HttpHost proxy, final boolean secure) {
Args.notNull(proxy, "Proxy host");
Asserts.check(this.connected, "No tunnel unless connected");
Asserts.notNull(this.proxyChain, "No tunnel without proxy");
// prepare an extended proxy chain
final HttpHost[] proxies = new HttpHost[this.proxyChain.length+1];
System.arraycopy(this.proxyChain, 0,
proxies, 0, this.proxyChain.length);
proxies[proxies.length-1] = proxy;
this.proxyChain = proxies;
this.secure = secure;
}
/**
* Tracks layering a protocol.
*
* @param secure {@code true} if the route is secure,
* {@code false} otherwise
*/
public final void layerProtocol(final boolean secure) {
// it is possible to layer a protocol over a direct connection,
// although this case is probably not considered elsewhere
Asserts.check(this.connected, "No layered protocol unless connected");
this.layered = LayerType.LAYERED;
this.secure = secure;
}
@Override
public final HttpHost getTargetHost() {
return this.targetHost;
}
@Override
public final InetAddress getLocalAddress() {
return this.localAddress;
}
@Override
public final int getHopCount() {
int hops = 0;
if (this.connected) {
if (proxyChain == null) {
hops = 1;
} else {
hops = proxyChain.length + 1;
}
}
return hops;
}
@Override
public final HttpHost getHopTarget(final int hop) {
Args.notNegative(hop, "Hop index");
final int hopcount = getHopCount();
Args.check(hop < hopcount, "Hop index exceeds tracked route length");
HttpHost result = null;
if (hop < hopcount-1) {
result = this.proxyChain[hop];
} else {
result = this.targetHost;
}
return result;
}
@Override
public final HttpHost getProxyHost() {
return (this.proxyChain == null) ? null : this.proxyChain[0];
}
public final boolean isConnected() {
return this.connected;
}
@Override
public final TunnelType getTunnelType() {
return this.tunnelled;
}
@Override
public final boolean isTunnelled() {
return (this.tunnelled == TunnelType.TUNNELLED);
}
@Override
public final LayerType getLayerType() {
return this.layered;
}
@Override
public final boolean isLayered() {
return (this.layered == LayerType.LAYERED);
}
@Override
public final boolean isSecure() {
return this.secure;
}
/**
* Obtains the tracked route.
* If a route has been tracked, it is {@link #isConnected connected}.
* If not connected, nothing has been tracked so far.
*
* @return the tracked route, or
* {@code null} if nothing has been tracked so far
*/
public final HttpRoute toRoute() {
return !this.connected ?
null : new HttpRoute(this.targetHost, this.localAddress,
this.proxyChain, this.secure,
this.tunnelled, this.layered);
}
/**
* Compares this tracked route to another.
*
* @param o the object to compare with
*
* @return {@code true} if the argument is the same tracked route,
* {@code false}
*/
@Override
public final boolean equals(final Object o) {
if (o == this) {
return true;
}
if (!(o instanceof RouteTracker)) {
return false;
}
final RouteTracker that = (RouteTracker) o;
return
// Do the cheapest checks first
(this.connected == that.connected) &&
(this.secure == that.secure) &&
(this.tunnelled == that.tunnelled) &&
(this.layered == that.layered) &&
LangUtils.equals(this.targetHost, that.targetHost) &&
LangUtils.equals(this.localAddress, that.localAddress) &&
LangUtils.equals(this.proxyChain, that.proxyChain);
}
/**
* Generates a hash code for this tracked route.
* Route trackers are modifiable and should therefore not be used
* as lookup keys. Use {@link #toRoute toRoute} to obtain an
* unmodifiable representation of the tracked route.
*
* @return the hash code
*/
@Override
public final int hashCode() {
int hash = LangUtils.HASH_SEED;
hash = LangUtils.hashCode(hash, this.targetHost);
hash = LangUtils.hashCode(hash, this.localAddress);
if (this.proxyChain != null) {
for (final HttpHost element : this.proxyChain) {
hash = LangUtils.hashCode(hash, element);
}
}
hash = LangUtils.hashCode(hash, this.connected);
hash = LangUtils.hashCode(hash, this.secure);
hash = LangUtils.hashCode(hash, this.tunnelled);
hash = LangUtils.hashCode(hash, this.layered);
return hash;
}
/**
* Obtains a description of the tracked route.
*
* @return a human-readable representation of the tracked route
*/
@Override
public final String toString() {
final StringBuilder cab = new StringBuilder(50 + getHopCount()*30);
cab.append("RouteTracker[");
if (this.localAddress != null) {
cab.append(this.localAddress);
cab.append("->");
}
cab.append('{');
if (this.connected) {
cab.append('c');
}
if (this.tunnelled == TunnelType.TUNNELLED) {
cab.append('t');
}
if (this.layered == LayerType.LAYERED) {
cab.append('l');
}
if (this.secure) {
cab.append('s');
}
cab.append("}->");
if (this.proxyChain != null) {
for (final HttpHost element : this.proxyChain) {
cab.append(element);
cab.append("->");
}
}
cab.append(this.targetHost);
cab.append(']');
return cab.toString();
}
// default implementation of clone() is sufficient
@Override
public Object clone() throws CloneNotSupportedException {
return super.clone();
}
}