alvinalexander.com | career | drupal | java | mac | mysql | perl | scala | uml | unix  

Java example source code file (HttpClient.java)

This example Java source code file (HttpClient.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

bufferedinputstream, http, http_continue, httpclient, httpurlconnection, ioexception, keepalive, meteredstream, net, network, new, override, post, posteroutputstream, progresssource, proxy, string, util, www

The HttpClient.java Java example source code

/*
 * Copyright (c) 1994, 2013, 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 sun.net.www.http;

import java.io.*;
import java.net.*;
import java.util.Locale;
import sun.net.NetworkClient;
import sun.net.ProgressSource;
import sun.net.www.MessageHeader;
import sun.net.www.HeaderParser;
import sun.net.www.MeteredStream;
import sun.net.www.ParseUtil;
import sun.net.www.protocol.http.HttpURLConnection;
import sun.util.logging.PlatformLogger;
import static sun.net.www.protocol.http.HttpURLConnection.TunnelState.*;

/**
 * @author Herb Jellinek
 * @author Dave Brown
 */
public class HttpClient extends NetworkClient {
    // whether this httpclient comes from the cache
    protected boolean cachedHttpClient = false;

    protected boolean inCache;

    // Http requests we send
    MessageHeader requests;

    // Http data we send with the headers
    PosterOutputStream poster = null;

    // true if we are in streaming mode (fixed length or chunked)
    boolean streaming;

    // if we've had one io error
    boolean failedOnce = false;

    /** Response code for CONTINUE */
    private boolean ignoreContinue = true;
    private static final int    HTTP_CONTINUE = 100;

    /** Default port number for http daemons. REMIND: make these private */
    static final int    httpPortNumber = 80;

    /** return default port number (subclasses may override) */
    protected int getDefaultPort () { return httpPortNumber; }

    static private int getDefaultPort(String proto) {
        if ("http".equalsIgnoreCase(proto))
            return 80;
        if ("https".equalsIgnoreCase(proto))
            return 443;
        return -1;
    }

    /* All proxying (generic as well as instance-specific) may be
     * disabled through use of this flag
     */
    protected boolean proxyDisabled;

    // are we using proxy in this instance?
    public boolean usingProxy = false;
    // target host, port for the URL
    protected String host;
    protected int port;

    /* where we cache currently open, persistent connections */
    protected static KeepAliveCache kac = new KeepAliveCache();

    private static boolean keepAliveProp = true;

    // retryPostProp is true by default so as to preserve behavior
    // from previous releases.
    private static boolean retryPostProp = true;

    volatile boolean keepingAlive = false;     /* this is a keep-alive connection */
    int keepAliveConnections = -1;    /* number of keep-alives left */

    /**Idle timeout value, in milliseconds. Zero means infinity,
     * iff keepingAlive=true.
     * Unfortunately, we can't always believe this one.  If I'm connected
     * through a Netscape proxy to a server that sent me a keep-alive
     * time of 15 sec, the proxy unilaterally terminates my connection
     * after 5 sec.  So we have to hard code our effective timeout to
     * 4 sec for the case where we're using a proxy. *SIGH*
     */
    int keepAliveTimeout = 0;

    /** whether the response is to be cached */
    private CacheRequest cacheRequest = null;

    /** Url being fetched. */
    protected URL       url;

    /* if set, the client will be reused and must not be put in cache */
    public boolean reuse = false;

    // Traffic capture tool, if configured. See HttpCapture class for info
    private HttpCapture capture = null;

    private static final PlatformLogger logger = HttpURLConnection.getHttpLogger();
    private static void logFinest(String msg) {
        if (logger.isLoggable(PlatformLogger.Level.FINEST)) {
            logger.finest(msg);
        }
    }

    /**
     * A NOP method kept for backwards binary compatibility
     * @deprecated -- system properties are no longer cached.
     */
    @Deprecated
    public static synchronized void resetProperties() {
    }

    int getKeepAliveTimeout() {
        return keepAliveTimeout;
    }

    static {
        String keepAlive = java.security.AccessController.doPrivileged(
            new sun.security.action.GetPropertyAction("http.keepAlive"));

        String retryPost = java.security.AccessController.doPrivileged(
            new sun.security.action.GetPropertyAction("sun.net.http.retryPost"));

        if (keepAlive != null) {
            keepAliveProp = Boolean.valueOf(keepAlive).booleanValue();
        } else {
            keepAliveProp = true;
        }

        if (retryPost != null) {
            retryPostProp = Boolean.valueOf(retryPost).booleanValue();
        } else
            retryPostProp = true;

    }

    /**
     * @return true iff http keep alive is set (i.e. enabled).  Defaults
     *          to true if the system property http.keepAlive isn't set.
     */
    public boolean getHttpKeepAliveSet() {
        return keepAliveProp;
    }


    protected HttpClient() {
    }

    private HttpClient(URL url)
    throws IOException {
        this(url, (String)null, -1, false);
    }

    protected HttpClient(URL url,
                         boolean proxyDisabled) throws IOException {
        this(url, null, -1, proxyDisabled);
    }

    /* This package-only CTOR should only be used for FTP piggy-backed on HTTP
     * HTTP URL's that use this won't take advantage of keep-alive.
     * Additionally, this constructor may be used as a last resort when the
     * first HttpClient gotten through New() failed (probably b/c of a
     * Keep-Alive mismatch).
     *
     * XXX That documentation is wrong ... it's not package-private any more
     */
    public HttpClient(URL url, String proxyHost, int proxyPort)
    throws IOException {
        this(url, proxyHost, proxyPort, false);
    }

    protected HttpClient(URL url, Proxy p, int to) throws IOException {
        proxy = (p == null) ? Proxy.NO_PROXY : p;
        this.host = url.getHost();
        this.url = url;
        port = url.getPort();
        if (port == -1) {
            port = getDefaultPort();
        }
        setConnectTimeout(to);

        capture = HttpCapture.getCapture(url);
        openServer();
    }

    static protected Proxy newHttpProxy(String proxyHost, int proxyPort,
                                      String proto) {
        if (proxyHost == null || proto == null)
            return Proxy.NO_PROXY;
        int pport = proxyPort < 0 ? getDefaultPort(proto) : proxyPort;
        InetSocketAddress saddr = InetSocketAddress.createUnresolved(proxyHost, pport);
        return new Proxy(Proxy.Type.HTTP, saddr);
    }

    /*
     * This constructor gives "ultimate" flexibility, including the ability
     * to bypass implicit proxying.  Sometimes we need to be using tunneling
     * (transport or network level) instead of proxying (application level),
     * for example when we don't want the application level data to become
     * visible to third parties.
     *
     * @param url               the URL to which we're connecting
     * @param proxy             proxy to use for this URL (e.g. forwarding)
     * @param proxyPort         proxy port to use for this URL
     * @param proxyDisabled     true to disable default proxying
     */
    private HttpClient(URL url, String proxyHost, int proxyPort,
                       boolean proxyDisabled)
        throws IOException {
        this(url, proxyDisabled ? Proxy.NO_PROXY :
             newHttpProxy(proxyHost, proxyPort, "http"), -1);
    }

    public HttpClient(URL url, String proxyHost, int proxyPort,
                       boolean proxyDisabled, int to)
        throws IOException {
        this(url, proxyDisabled ? Proxy.NO_PROXY :
             newHttpProxy(proxyHost, proxyPort, "http"), to);
    }

    /* This class has no public constructor for HTTP.  This method is used to
     * get an HttpClient to the specified URL.  If there's currently an
     * active HttpClient to that server/port, you'll get that one.
     */
    public static HttpClient New(URL url)
    throws IOException {
        return HttpClient.New(url, Proxy.NO_PROXY, -1, true, null);
    }

    public static HttpClient New(URL url, boolean useCache)
        throws IOException {
        return HttpClient.New(url, Proxy.NO_PROXY, -1, useCache, null);
    }

    public static HttpClient New(URL url, Proxy p, int to, boolean useCache,
        HttpURLConnection httpuc) throws IOException
    {
        if (p == null) {
            p = Proxy.NO_PROXY;
        }
        HttpClient ret = null;
        /* see if one's already around */
        if (useCache) {
            ret = kac.get(url, null);
            if (ret != null && httpuc != null &&
                httpuc.streaming() &&
                httpuc.getRequestMethod() == "POST") {
                if (!ret.available()) {
                    ret.inCache = false;
                    ret.closeServer();
                    ret = null;
                }
            }

            if (ret != null) {
                if ((ret.proxy != null && ret.proxy.equals(p)) ||
                    (ret.proxy == null && p == null)) {
                    synchronized (ret) {
                        ret.cachedHttpClient = true;
                        assert ret.inCache;
                        ret.inCache = false;
                        if (httpuc != null && ret.needsTunneling())
                            httpuc.setTunnelState(TUNNELING);
                        logFinest("KeepAlive stream retrieved from the cache, " + ret);
                    }
                } else {
                    // We cannot return this connection to the cache as it's
                    // KeepAliveTimeout will get reset. We simply close the connection.
                    // This should be fine as it is very rare that a connection
                    // to the same host will not use the same proxy.
                    synchronized(ret) {
                        ret.inCache = false;
                        ret.closeServer();
                    }
                    ret = null;
                }
            }
        }
        if (ret == null) {
            ret = new HttpClient(url, p, to);
        } else {
            SecurityManager security = System.getSecurityManager();
            if (security != null) {
                if (ret.proxy == Proxy.NO_PROXY || ret.proxy == null) {
                    security.checkConnect(InetAddress.getByName(url.getHost()).getHostAddress(), url.getPort());
                } else {
                    security.checkConnect(url.getHost(), url.getPort());
                }
            }
            ret.url = url;
        }
        return ret;
    }

    public static HttpClient New(URL url, Proxy p, int to,
        HttpURLConnection httpuc) throws IOException
    {
        return New(url, p, to, true, httpuc);
    }

    public static HttpClient New(URL url, String proxyHost, int proxyPort,
                                 boolean useCache)
        throws IOException {
        return New(url, newHttpProxy(proxyHost, proxyPort, "http"),
            -1, useCache, null);
    }

    public static HttpClient New(URL url, String proxyHost, int proxyPort,
                                 boolean useCache, int to,
                                 HttpURLConnection httpuc)
        throws IOException {
        return New(url, newHttpProxy(proxyHost, proxyPort, "http"),
            to, useCache, httpuc);
    }

    /* return it to the cache as still usable, if:
     * 1) It's keeping alive, AND
     * 2) It still has some connections left, AND
     * 3) It hasn't had a error (PrintStream.checkError())
     * 4) It hasn't timed out
     *
     * If this client is not keepingAlive, it should have been
     * removed from the cache in the parseHeaders() method.
     */

    public void finished() {
        if (reuse) /* will be reused */
            return;
        keepAliveConnections--;
        poster = null;
        if (keepAliveConnections > 0 && isKeepingAlive() &&
               !(serverOutput.checkError())) {
            /* This connection is keepingAlive && still valid.
             * Return it to the cache.
             */
            putInKeepAliveCache();
        } else {
            closeServer();
        }
    }

    protected synchronized boolean available() {
        boolean available = true;
        int old = -1;

        try {
            try {
                old = serverSocket.getSoTimeout();
                serverSocket.setSoTimeout(1);
                BufferedInputStream tmpbuf =
                        new BufferedInputStream(serverSocket.getInputStream());
                int r = tmpbuf.read();
                if (r == -1) {
                    logFinest("HttpClient.available(): " +
                            "read returned -1: not available");
                    available = false;
                }
            } catch (SocketTimeoutException e) {
                logFinest("HttpClient.available(): " +
                        "SocketTimeout: its available");
            } finally {
                if (old != -1)
                    serverSocket.setSoTimeout(old);
            }
        } catch (IOException e) {
            logFinest("HttpClient.available(): " +
                        "SocketException: not available");
            available = false;
        }
        return available;
    }

    protected synchronized void putInKeepAliveCache() {
        if (inCache) {
            assert false : "Duplicate put to keep alive cache";
            return;
        }
        inCache = true;
        kac.put(url, null, this);
    }

    protected synchronized boolean isInKeepAliveCache() {
        return inCache;
    }

    /*
     * Close an idle connection to this URL (if it exists in the
     * cache).
     */
    public void closeIdleConnection() {
        HttpClient http = kac.get(url, null);
        if (http != null) {
            http.closeServer();
        }
    }

    /* We're very particular here about what our InputStream to the server
     * looks like for reasons that are apparent if you can decipher the
     * method parseHTTP().  That's why this method is overidden from the
     * superclass.
     */
    @Override
    public void openServer(String server, int port) throws IOException {
        serverSocket = doConnect(server, port);
        try {
            OutputStream out = serverSocket.getOutputStream();
            if (capture != null) {
                out = new HttpCaptureOutputStream(out, capture);
            }
            serverOutput = new PrintStream(
                new BufferedOutputStream(out),
                                         false, encoding);
        } catch (UnsupportedEncodingException e) {
            throw new InternalError(encoding+" encoding not found", e);
        }
        serverSocket.setTcpNoDelay(true);
    }

    /*
     * Returns true if the http request should be tunneled through proxy.
     * An example where this is the case is Https.
     */
    public boolean needsTunneling() {
        return false;
    }

    /*
     * Returns true if this httpclient is from cache
     */
    public synchronized boolean isCachedConnection() {
        return cachedHttpClient;
    }

    /*
     * Finish any work left after the socket connection is
     * established.  In the normal http case, it's a NO-OP. Subclass
     * may need to override this. An example is Https, where for
     * direct connection to the origin server, ssl handshake needs to
     * be done; for proxy tunneling, the socket needs to be converted
     * into an SSL socket before ssl handshake can take place.
     */
    public void afterConnect() throws IOException, UnknownHostException {
        // NO-OP. Needs to be overwritten by HttpsClient
    }

    /*
     * call openServer in a privileged block
     */
    private synchronized void privilegedOpenServer(final InetSocketAddress server)
         throws IOException
    {
        try {
            java.security.AccessController.doPrivileged(
                new java.security.PrivilegedExceptionAction<Void>() {
                    public Void run() throws IOException {
                    openServer(server.getHostString(), server.getPort());
                    return null;
                }
            });
        } catch (java.security.PrivilegedActionException pae) {
            throw (IOException) pae.getException();
        }
    }

    /*
     * call super.openServer
     */
    private void superOpenServer(final String proxyHost,
                                 final int proxyPort)
        throws IOException, UnknownHostException
    {
        super.openServer(proxyHost, proxyPort);
    }

    /*
     */
    protected synchronized void openServer() throws IOException {

        SecurityManager security = System.getSecurityManager();

        if (security != null) {
            security.checkConnect(host, port);
        }

        if (keepingAlive) { // already opened
            return;
        }

        if (url.getProtocol().equals("http") ||
            url.getProtocol().equals("https") ) {

            if ((proxy != null) && (proxy.type() == Proxy.Type.HTTP)) {
                sun.net.www.URLConnection.setProxiedHost(host);
                privilegedOpenServer((InetSocketAddress) proxy.address());
                usingProxy = true;
                return;
            } else {
                // make direct connection
                openServer(host, port);
                usingProxy = false;
                return;
            }

        } else {
            /* we're opening some other kind of url, most likely an
             * ftp url.
             */
            if ((proxy != null) && (proxy.type() == Proxy.Type.HTTP)) {
                sun.net.www.URLConnection.setProxiedHost(host);
                privilegedOpenServer((InetSocketAddress) proxy.address());
                usingProxy = true;
                return;
            } else {
                // make direct connection
                super.openServer(host, port);
                usingProxy = false;
                return;
            }
        }
    }

    public String getURLFile() throws IOException {

        String fileName;

        /**
         * proxyDisabled is set by subclass HttpsClient!
         */
        if (usingProxy && !proxyDisabled) {
            // Do not use URLStreamHandler.toExternalForm as the fragment
            // should not be part of the RequestURI. It should be an
            // absolute URI which does not have a fragment part.
            StringBuffer result = new StringBuffer(128);
            result.append(url.getProtocol());
            result.append(":");
            if (url.getAuthority() != null && url.getAuthority().length() > 0) {
                result.append("//");
                result.append(url.getAuthority());
            }
            if (url.getPath() != null) {
                result.append(url.getPath());
            }
            if (url.getQuery() != null) {
                result.append('?');
                result.append(url.getQuery());
            }

            fileName = result.toString();
        } else {
            fileName = url.getFile();

            if ((fileName == null) || (fileName.length() == 0)) {
                fileName = "/";
            } else if (fileName.charAt(0) == '?') {
                /* HTTP/1.1 spec says in 5.1.2. about Request-URI:
                 * "Note that the absolute path cannot be empty; if
                 * none is present in the original URI, it MUST be
                 * given as "/" (the server root)."  So if the file
                 * name here has only a query string, the path is
                 * empty and we also have to add a "/".
                 */
                fileName = "/" + fileName;
            }
        }

        if (fileName.indexOf('\n') == -1)
            return fileName;
        else
            throw new java.net.MalformedURLException("Illegal character in URL");
    }

    /**
     * @deprecated
     */
    @Deprecated
    public void writeRequests(MessageHeader head) {
        requests = head;
        requests.print(serverOutput);
        serverOutput.flush();
    }

    public void writeRequests(MessageHeader head,
                              PosterOutputStream pos) throws IOException {
        requests = head;
        requests.print(serverOutput);
        poster = pos;
        if (poster != null)
            poster.writeTo(serverOutput);
        serverOutput.flush();
    }

    public void writeRequests(MessageHeader head,
                              PosterOutputStream pos,
                              boolean streaming) throws IOException {
        this.streaming = streaming;
        writeRequests(head, pos);
    }

    /** Parse the first line of the HTTP request.  It usually looks
        something like: "HTTP/1.0 <number> comment\r\n". */

    public boolean parseHTTP(MessageHeader responses, ProgressSource pi, HttpURLConnection httpuc)
    throws IOException {
        /* If "HTTP/*" is found in the beginning, return true.  Let
         * HttpURLConnection parse the mime header itself.
         *
         * If this isn't valid HTTP, then we don't try to parse a header
         * out of the beginning of the response into the responses,
         * and instead just queue up the output stream to it's very beginning.
         * This seems most reasonable, and is what the NN browser does.
         */

        try {
            serverInput = serverSocket.getInputStream();
            if (capture != null) {
                serverInput = new HttpCaptureInputStream(serverInput, capture);
            }
            serverInput = new BufferedInputStream(serverInput);
            return (parseHTTPHeader(responses, pi, httpuc));
        } catch (SocketTimeoutException stex) {
            // We don't want to retry the request when the app. sets a timeout
            // but don't close the server if timeout while waiting for 100-continue
            if (ignoreContinue) {
                closeServer();
            }
            throw stex;
        } catch (IOException e) {
            closeServer();
            cachedHttpClient = false;
            if (!failedOnce && requests != null) {
                failedOnce = true;
                if (getRequestMethod().equals("CONNECT") ||
                    (httpuc.getRequestMethod().equals("POST") &&
                    (!retryPostProp || streaming))) {
                    // do not retry the request
                }  else {
                    // try once more
                    openServer();
                    if (needsTunneling()) {
                        httpuc.doTunneling();
                    }
                    afterConnect();
                    writeRequests(requests, poster);
                    return parseHTTP(responses, pi, httpuc);
                }
            }
            throw e;
        }

    }

    private boolean parseHTTPHeader(MessageHeader responses, ProgressSource pi, HttpURLConnection httpuc)
    throws IOException {
        /* If "HTTP/*" is found in the beginning, return true.  Let
         * HttpURLConnection parse the mime header itself.
         *
         * If this isn't valid HTTP, then we don't try to parse a header
         * out of the beginning of the response into the responses,
         * and instead just queue up the output stream to it's very beginning.
         * This seems most reasonable, and is what the NN browser does.
         */

        keepAliveConnections = -1;
        keepAliveTimeout = 0;

        boolean ret = false;
        byte[] b = new byte[8];

        try {
            int nread = 0;
            serverInput.mark(10);
            while (nread < 8) {
                int r = serverInput.read(b, nread, 8 - nread);
                if (r < 0) {
                    break;
                }
                nread += r;
            }
            String keep=null;
            ret = b[0] == 'H' && b[1] == 'T'
                    && b[2] == 'T' && b[3] == 'P' && b[4] == '/' &&
                b[5] == '1' && b[6] == '.';
            serverInput.reset();
            if (ret) { // is valid HTTP - response started w/ "HTTP/1."
                responses.parseHeader(serverInput);

                // we've finished parsing http headers
                // check if there are any applicable cookies to set (in cache)
                CookieHandler cookieHandler = httpuc.getCookieHandler();
                if (cookieHandler != null) {
                    URI uri = ParseUtil.toURI(url);
                    // NOTE: That cast from Map shouldn't be necessary but
                    // a bug in javac is triggered under certain circumstances
                    // So we do put the cast in as a workaround until
                    // it is resolved.
                    if (uri != null)
                        cookieHandler.put(uri, responses.getHeaders());
                }

                /* decide if we're keeping alive:
                 * This is a bit tricky.  There's a spec, but most current
                 * servers (10/1/96) that support this differ in dialects.
                 * If the server/client misunderstand each other, the
                 * protocol should fall back onto HTTP/1.0, no keep-alive.
                 */
                if (usingProxy) { // not likely a proxy will return this
                    keep = responses.findValue("Proxy-Connection");
                }
                if (keep == null) {
                    keep = responses.findValue("Connection");
                }
                if (keep != null && keep.toLowerCase(Locale.US).equals("keep-alive")) {
                    /* some servers, notably Apache1.1, send something like:
                     * "Keep-Alive: timeout=15, max=1" which we should respect.
                     */
                    HeaderParser p = new HeaderParser(
                            responses.findValue("Keep-Alive"));
                    if (p != null) {
                        /* default should be larger in case of proxy */
                        keepAliveConnections = p.findInt("max", usingProxy?50:5);
                        keepAliveTimeout = p.findInt("timeout", usingProxy?60:5);
                    }
                } else if (b[7] != '0') {
                    /*
                     * We're talking 1.1 or later. Keep persistent until
                     * the server says to close.
                     */
                    if (keep != null) {
                        /*
                         * The only Connection token we understand is close.
                         * Paranoia: if there is any Connection header then
                         * treat as non-persistent.
                         */
                        keepAliveConnections = 1;
                    } else {
                        keepAliveConnections = 5;
                    }
                }
            } else if (nread != 8) {
                if (!failedOnce && requests != null) {
                    failedOnce = true;
                    if (getRequestMethod().equals("CONNECT") ||
                        (httpuc.getRequestMethod().equals("POST") &&
                         (!retryPostProp || streaming))) {
                        // do not retry the request
                    } else {
                        closeServer();
                        cachedHttpClient = false;
                        openServer();
                        if (needsTunneling()) {
                            httpuc.doTunneling();
                        }
                        afterConnect();
                        writeRequests(requests, poster);
                        return parseHTTP(responses, pi, httpuc);
                    }
                }
                throw new SocketException("Unexpected end of file from server");
            } else {
                // we can't vouche for what this is....
                responses.set("Content-type", "unknown/unknown");
            }
        } catch (IOException e) {
            throw e;
        }

        int code = -1;
        try {
            String resp;
            resp = responses.getValue(0);
            /* should have no leading/trailing LWS
             * expedite the typical case by assuming it has
             * form "HTTP/1.x <WS> 2XX "
             */
            int ind;
            ind = resp.indexOf(' ');
            while(resp.charAt(ind) == ' ')
                ind++;
            code = Integer.parseInt(resp.substring(ind, ind + 3));
        } catch (Exception e) {}

        if (code == HTTP_CONTINUE && ignoreContinue) {
            responses.reset();
            return parseHTTPHeader(responses, pi, httpuc);
        }

        long cl = -1;

        /*
         * Set things up to parse the entity body of the reply.
         * We should be smarter about avoid pointless work when
         * the HTTP method and response code indicate there will be
         * no entity body to parse.
         */
        String te = responses.findValue("Transfer-Encoding");
        if (te != null && te.equalsIgnoreCase("chunked")) {
            serverInput = new ChunkedInputStream(serverInput, this, responses);

            /*
             * If keep alive not specified then close after the stream
             * has completed.
             */
            if (keepAliveConnections <= 1) {
                keepAliveConnections = 1;
                keepingAlive = false;
            } else {
                keepingAlive = true;
            }
            failedOnce = false;
        } else {

            /*
             * If it's a keep alive connection then we will keep
             * (alive if :-
             * 1. content-length is specified, or
             * 2. "Not-Modified" or "No-Content" responses - RFC 2616 states that
             *    204 or 304 response must not include a message body.
             */
            String cls = responses.findValue("content-length");
            if (cls != null) {
                try {
                    cl = Long.parseLong(cls);
                } catch (NumberFormatException e) {
                    cl = -1;
                }
            }
            String requestLine = requests.getKey(0);

            if ((requestLine != null &&
                 (requestLine.startsWith("HEAD"))) ||
                code == HttpURLConnection.HTTP_NOT_MODIFIED ||
                code == HttpURLConnection.HTTP_NO_CONTENT) {
                cl = 0;
            }

            if (keepAliveConnections > 1 &&
                (cl >= 0 ||
                 code == HttpURLConnection.HTTP_NOT_MODIFIED ||
                 code == HttpURLConnection.HTTP_NO_CONTENT)) {
                keepingAlive = true;
                failedOnce = false;
            } else if (keepingAlive) {
                /* Previously we were keeping alive, and now we're not.  Remove
                 * this from the cache (but only here, once) - otherwise we get
                 * multiple removes and the cache count gets messed up.
                 */
                keepingAlive=false;
            }
        }

        /* wrap a KeepAliveStream/MeteredStream around it if appropriate */

        if (cl > 0) {
            // In this case, content length is well known, so it is okay
            // to wrap the input stream with KeepAliveStream/MeteredStream.

            if (pi != null) {
                // Progress monitor is enabled
                pi.setContentType(responses.findValue("content-type"));
            }

            if (isKeepingAlive())   {
                // Wrap KeepAliveStream if keep alive is enabled.
                logFinest("KeepAlive stream used: " + url);
                serverInput = new KeepAliveStream(serverInput, pi, cl, this);
                failedOnce = false;
            }
            else        {
                serverInput = new MeteredStream(serverInput, pi, cl);
            }
        }
        else if (cl == -1)  {
            // In this case, content length is unknown - the input
            // stream would simply be a regular InputStream or
            // ChunkedInputStream.

            if (pi != null) {
                // Progress monitoring is enabled.

                pi.setContentType(responses.findValue("content-type"));

                // Wrap MeteredStream for tracking indeterministic
                // progress, even if the input stream is ChunkedInputStream.
                serverInput = new MeteredStream(serverInput, pi, cl);
            }
            else    {
                // Progress monitoring is disabled, and there is no
                // need to wrap an unknown length input stream.

                // ** This is an no-op **
            }
        }
        else    {
            if (pi != null)
                pi.finishTracking();
        }

        return ret;
    }

    public synchronized InputStream getInputStream() {
        return serverInput;
    }

    public OutputStream getOutputStream() {
        return serverOutput;
    }

    @Override
    public String toString() {
        return getClass().getName()+"("+url+")";
    }

    public final boolean isKeepingAlive() {
        return getHttpKeepAliveSet() && keepingAlive;
    }

    public void setCacheRequest(CacheRequest cacheRequest) {
        this.cacheRequest = cacheRequest;
    }

    CacheRequest getCacheRequest() {
        return cacheRequest;
    }

    String getRequestMethod() {
        if (requests != null) {
            String requestLine = requests.getKey(0);
            if (requestLine != null) {
               return requestLine.split("\\s+")[0];
            }
        }
        return "";
    }

    @Override
    protected void finalize() throws Throwable {
        // This should do nothing.  The stream finalizer will
        // close the fd.
    }

    public void setDoNotRetry(boolean value) {
        // failedOnce is used to determine if a request should be retried.
        failedOnce = value;
    }

    public void setIgnoreContinue(boolean value) {
        ignoreContinue = value;
    }

    /* Use only on connections in error. */
    @Override
    public void closeServer() {
        try {
            keepingAlive = false;
            serverSocket.close();
        } catch (Exception e) {}
    }

    /**
     * @return the proxy host being used for this client, or null
     *          if we're not going through a proxy
     */
    public String getProxyHostUsed() {
        if (!usingProxy) {
            return null;
        } else {
            return ((InetSocketAddress)proxy.address()).getHostString();
        }
    }

    /**
     * @return the proxy port being used for this client.  Meaningless
     *          if getProxyHostUsed() gives null.
     */
    public int getProxyPortUsed() {
        if (usingProxy)
            return ((InetSocketAddress)proxy.address()).getPort();
        return -1;
    }
}

Other Java examples (source code examples)

Here is a short list of links related to this Java HttpClient.java source code file:

... this post is sponsored by my books ...

#1 New Release!

FP Best Seller

 

new blog posts

 

Copyright 1998-2021 Alvin Alexander, alvinalexander.com
All Rights Reserved.

A percentage of advertising revenue from
pages under the /java/jwarehouse URI on this website is
paid back to open source projects.