Java example source code file (EndpointAddress.java)

This example Java source code file (EndpointAddress.java) is included in the alvinalexander.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Learn more about this Java project at its project page.

Java - Java tags/keywords

endpointaddress, illegal, ioexception, iterator, malformedurlexception, net, network, override, proxy, proxyselector, string, uri, urisyntaxexception, url, urlconnection, util, webserviceexception, xml

The EndpointAddress.java Java example source code

/*
 * Copyright (c) 1997, 2012, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 */

package com.sun.xml.internal.ws.api;

import com.sun.istack.internal.Nullable;

import javax.xml.ws.WebServiceException;
import java.io.IOException;
import java.net.MalformedURLException;
import java.net.Proxy;
import java.net.ProxySelector;
import java.net.URI;
import java.net.URISyntaxException;
import java.net.URL;
import java.net.URLConnection;
import java.net.URLStreamHandler;
import java.util.Iterator;

/**
 * Represents the endpoint address URI.
 *
 * <p>
 * Conceptually this can be really thought of as an {@link URI},
 * but it hides some of the details that improve the performance.
 *
 * <p>
 * Being an {@link URI} allows this class to represent custom made-up URIs
 * (like "jms" for example.) Whenever possible, this object
 * also creates an {@link URL} (this is only possible when the address
 * has a registered {@link URLStreamHandler}), so that if the clients
 * of this code wants to use it, it can do so.
 *
 *
 * <h3>How it improves the performance
 * <ol>
 *  <li>
 *  Endpoint address is often eventually turned into an {@link URLConnection},
 *  and given that generally this value is read more often than being set,
 *  it makes sense to eagerly turn it into an {@link URL},
 *  thereby avoiding a repeated conversion.
 *
 *  <li>
 *  JDK spends a lot of time choosing a list of {@link Proxy}
 *  to connect to an {@link URL}. Since the default proxy selector
 *  implementation always return the same proxy for the same URL,
 *  we can determine the proxy by ourselves to let JDK skip its
 *  proxy-discovery step.
 *
 *  (That said, user-defined proxy selector can do a lot of interesting things
 *  --- like doing a round-robin, or pick one from a proxy farm randomly,
 *  and so it's dangerous to stick to one proxy. For this case,
 *  we still let JDK decide the proxy. This shouldn't be that much of an
 *  disappointment, since most people only mess with system properties,
 *  and never with {@link ProxySelector}. Also, avoiding optimization
 *  with non-standard proxy selector allows people to effectively disable
 *  this optimization, which may come in handy for a trouble-shooting.)
 * </ol>
 *
 * @author Kohsuke Kawaguchi
 */
public final class EndpointAddress {
    @Nullable
    private URL url;
    private final URI uri;
    private final String stringForm;
    private volatile boolean dontUseProxyMethod;
    /**
     * Pre-selected proxy.
     *
     * If {@link #url} is null, this field is null.
     * Otherwise, this field could still be null if the proxy couldn't be chosen
     * upfront.
     */
    private Proxy proxy;

    public EndpointAddress(URI uri) {
        this.uri = uri;
        this.stringForm = uri.toString();
        try {
            initURL();
            proxy = chooseProxy();
        } catch (MalformedURLException e) {
            // ignore
        }
    }

    /**
     *
     * @see #create(String)
     */
    public EndpointAddress(String url) throws URISyntaxException {
        this.uri = new URI(url);
        this.stringForm = url;
        try {
            initURL();
            proxy = chooseProxy();
        } catch (MalformedURLException e) {
            // ignore
        }
    }


    private void initURL() throws MalformedURLException {
        String scheme = uri.getScheme();
        //URI.toURL() only works when scheme is not null.
        if (scheme == null) {
            this.url = new URL(uri.toString());
            return;
        }
        scheme =scheme.toLowerCase();
        if ("http".equals(scheme) || "https".equals(scheme)) {
            url = new URL(uri.toASCIIString());
        } else {
            this.url = uri.toURL();
        }
    }

    /**
     * Creates a new {@link EndpointAddress} with a reasonably
     * generic error handling.
     */
    public static EndpointAddress create(String url) {
        try {
            return new EndpointAddress(url);
        } catch(URISyntaxException e) {
            throw new WebServiceException("Illegal endpoint address: "+url,e);
        }
    }

    private Proxy chooseProxy() {
        ProxySelector sel =
            java.security.AccessController.doPrivileged(
                new java.security.PrivilegedAction<ProxySelector>() {
                    @Override
                    public ProxySelector run() {
                        return ProxySelector.getDefault();
                    }
                });

        if(sel==null)
            return Proxy.NO_PROXY;


        if(!sel.getClass().getName().equals("sun.net.spi.DefaultProxySelector"))
            // user-defined proxy. may return a different proxy for each invocation
            return null;

        Iterator<Proxy> it = sel.select(uri).iterator();
        if(it.hasNext())
            return it.next();

        return Proxy.NO_PROXY;
    }

    /**
     * Returns an URL of this endpoint adress.
     *
     * @return
     *      null if this endpoint address doesn't have a registered {@link URLStreamHandler}.
     */
    public URL getURL() {
        return url;
    }

    /**
     * Returns an URI of the endpoint address.
     *
     * @return
     *      always non-null.
     */
    public URI getURI() {
        return uri;
    }

    /**
     * Tries to open {@link URLConnection} for this endpoint.
     *
     * <p>
     * This is possible only when an endpoint address has
     * the corresponding {@link URLStreamHandler}.
     *
     * @throws IOException
     *      if {@link URL#openConnection()} reports an error.
     * @throws AssertionError
     *      if this endpoint doesn't have an associated URL.
     *      if the code is written correctly this shall never happen.
     */
    public URLConnection openConnection() throws IOException {
        if (url == null) {
            throw new WebServiceException("URI="+uri+" doesn't have the corresponding URL");
        }
        if(proxy!=null && !dontUseProxyMethod) {
            try {
                return url.openConnection(proxy);
            } catch(UnsupportedOperationException e) {
                // Some OSGi and app server environments donot
                // override URLStreamHandler.openConnection(URL, Proxy) as it
                // is introduced in Java SE 5 API. Fallback to the other method.
                dontUseProxyMethod = true;
            }
        }
        return url.openConnection();
    }

    @Override
    public String toString() {
        return stringForm;
    }
}