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| Version: 9.4.28-SNAPSHOT</span></td><td style="width: 50%"></td></tr></table><div xmlns:jfetch="java:org.eclipse.jetty.xslt.tools.JavaSourceFetchExtension" xmlns:fetch="java:org.eclipse.jetty.xslt.tools.SourceFetchExtension" xmlns:d="http://docbook.org/ns/docbook" xmlns:l="http://docbook.sourceforge.net/xmlns/l10n/1.0" xmlns:xslthl="http://xslthl.sf.net" xmlns:gcse="http://www.google.com" xmlns:date="http://exslt.org/dates-and-times" class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="3" align="center">Chapter 15. Application Layer Protocol Negotiation (ALPN)</th></tr><tr><td width="20%" align="left"><a accesskey="p" href="jetty-jconsole.html"><i class="fa fa-chevron-left" aria-hidden="true"></i> Previous</a> </td><th width="60%" align="center">Part III. Jetty Administration Guide<br><a accesskey="p" href="index.html"><i class="fa fa-home" aria-hidden="true"></i> Home</a></th><td width="20%" align="right"> <a accesskey="n" href="http2.html">Next <i class="fa fa-chevron-right" aria-hidden="true"></i></a></td></tr></table><hr></div><div xmlns:jfetch="java:org.eclipse.jetty.xslt.tools.JavaSourceFetchExtension" xmlns:fetch="java:org.eclipse.jetty.xslt.tools.SourceFetchExtension" xmlns:d="http://docbook.org/ns/docbook" xmlns:l="http://docbook.sourceforge.net/xmlns/l10n/1.0" xmlns:xslthl="http://xslthl.sf.net" xmlns:gcse="http://www.google.com" xmlns:date="http://exslt.org/dates-and-times" class="jetty-callout"><h5 class="callout"><a href="http://www.webtide.com/">Contact the core Jetty developers at |
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| </p></div><div class="chapter"><div class="titlepage"><div><div><h2 class="title"><a name="alpn-chapter"></a>Chapter 15. Application Layer Protocol Negotiation (ALPN)</h2></div></div></div><div class="toc"><p><b>Table of Contents</b></p><dl class="toc"><dt><span class="section"><a href="alpn-chapter.html#alpn">Introducing ALPN</a></span></dt></dl></div><p>The development of new web protocols such as HTTP/2 raised the need of protocol |
| negotiation within a Transport Layer Security (TLS) handshake. |
| A protocol negotiation called ALPN (Application Layer Protocol Negotiation - |
| <a class="link" href="https://tools.ietf.org/html/rfc7301" target="_top">RFC7301</a>) has been defined to accomplish this.</p><p>ALPN has now replaced the older (and now fully deprecated) NPN in the general Web |
| as of 2016.</p><p>For those browsers that support HTTP/2, they all now support ALPN. |
| Starting with Jetty 9.3.0, only ALPN is supported by Jetty.</p><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="alpn"></a>Introducing ALPN</h2></div></div></div><div class="toc"><dl class="toc"><dt><span class="section"><a href="alpn-chapter.html#alpn-openjdk8">ALPN and OpenJDK 8</a></span></dt><dt><span class="section"><a href="alpn-chapter.html#alpn-conscrypt">ALPN and Conscrypt</a></span></dt><dt><span class="section"><a href="alpn-chapter.html#alpn-jdk9">ALPN and JDK 9</a></span></dt><dt><span class="section"><a href="alpn-chapter.html#alpn-troubleshooting">ALPN Troubleshooting</a></span></dt><dt><span class="section"><a href="alpn-chapter.html#alpn-openjdk8-details">Details about ALPN and OpenJDK 8</a></span></dt><dt><span class="section"><a href="alpn-chapter.html#alpn-openjdk8-client-example">Client Example</a></span></dt><dt><span class="section"><a href="alpn-chapter.html#alpn-openjdk8-server-example">Server Example</a></span></dt><dt><span class="section"><a href="alpn-chapter.html#alpn-openjdk8-implementation">Implementation Details</a></span></dt><dt><span class="section"><a href="alpn-chapter.html#alpn-openjdk8-tests">Unit Tests</a></span></dt><dt><span class="section"><a href="alpn-chapter.html#alpn-openjdk8-debugging">Debugging</a></span></dt><dt><span class="section"><a href="alpn-chapter.html#alpn-openjdk8-license-details">License Details</a></span></dt><dt><span class="section"><a href="alpn-chapter.html#alpn-versions">Versions</a></span></dt><dt><span class="section"><a href="alpn-chapter.html#alpn-build">How to build ALPN</a></span></dt></dl></div><p>Application Layer Protocol Negotiation (ALPN) is a TLS extension that allows client and server to negotiate the application protocol that they will use to communicate within the encryption provided by TLS.</p><p>Any protocol can be negotiated by ALPN within a TLS connection; the protocols that are most commonly negotiated are HTTP/2 and HTTP/1.1.</p><p>Browsers only support HTTP/2 over TLS by negotiating the HTTP/2 protocol via ALPN. |
| You need to configure the server to support TLS and ALPN if you want browsers to use |
| the HTTP/2 protocol, otherwise they will default to HTTP/1.1.</p><p>In the Jetty project, ALPN is <span class="emphasis"><em>used</em></span> in two artifacts: <code class="literal">jetty-alpn-client</code> and <code class="literal">jetty-alpn-server</code>, respectively for the client and for the server.</p><p>When using Jetty as a standalone server via the Jetty distribution, the <code class="literal">jetty-alpn-server</code> artifact is automatically included in the server classpath by the Jetty module system.</p><p>When using Jetty embedded, the <code class="literal">jetty-alpn-client</code> and <code class="literal">jetty-alpn-server</code> artifacts must be included in the classpath, respectively for client and server use cases.</p><p>The ALPN implementation is <span class="emphasis"><em>provided</em></span> to these two artifacts with the following three options:</p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p class="simpara">For JDK 8 only, a provider based on modified OpenJDK classes</p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: circle; "><li class="listitem">Only works with JDK 8, pure Java implementation</li><li class="listitem">Requires the <code class="literal">-Xbootclasspath/p</code> option on command line</li></ul></div></li><li class="listitem"><p class="simpara">For JDK 8 or later, a provider based on the <a class="link" href="configuring-ssl.html#conscrypt" title="Conscrypt SSL">Conscrypt security provider</a></p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: circle; "><li class="listitem">Works with JDK 8 or later and provides improved performance</li><li class="listitem">Binds to the OpenSSL native library shipped by Conscrypt and is therefore only available on the platforms supported by Conscrypt</li></ul></div></li><li class="listitem"><p class="simpara">For JDK 9 or later, a provider based on the ALPN APIs present in the JDK</p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: circle; "><li class="listitem">Works with JDK 9 or later, pure Java implementation</li><li class="listitem">Lower performance than Conscrypt</li></ul></div></li></ul></div><p>The first, although hosted under the umbrella of the Jetty project, is independent of Jetty (the Servlet Container); you can use it in any other Java network server.</p><p>Each provider above provides an ALPN <span class="emphasis"><em>service</em></span> implementation; Jetty uses the <code class="literal">ServiceLoader</code> mechanism to load these service implementations. |
| At least one valid provider must be present in the server classpath. |
| For example, using JDK 8 with the JDK 9 ALPN provider is an <span class="emphasis"><em>invalid</em></span> combination. |
| The absence of valid implementations is an error at startup (see also the <a class="link" href="alpn-chapter.html#alpn-troubleshooting" title="ALPN Troubleshooting">troubleshooting section</a>).</p><p>There may be multiple ALPN service providers in the server classpath. |
| When a new connection is created, an <code class="literal">SSLEngine</code> instance is associated to it; each <code class="literal">SSLEngine</code> is passed all service implementations, until one accepts it.</p><p>It is therefore possible to have multiple providers active at the same time, for example the JDK 9 provider and the Conscrypt provider, and at runtime the correct one will be chosen by the Jetty runtime.</p><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="alpn-openjdk8"></a>ALPN and OpenJDK 8</h3></div></div></div><p>When using JDKs based on OpenJDK 8 (for JDK 9 see <a class="link" href="alpn-chapter.html#alpn-jdk9" title="ALPN and JDK 9">above</a>), and you do not or cannot use <a class="link" href="configuring-ssl.html#conscrypt" title="Conscrypt SSL">Conscrypt</a>, you can use Jetty’s ALPN boot library to provide the ALPN service implementation, via the <code class="literal">alpn-boot</code> artifact.</p><p>The Jetty ALPN boot library modifies the relevant OpenJDK classes to add ALPN support and provides an ALPN API that application can use to enable ALPN.</p><p>When using Jetty as a standalone server via the Jetty distribution, ALPN support is automatically enabled when the <code class="literal">http2</code> module is enabled. |
| This enables transitively the <code class="literal">alpn-8</code> module which puts the <code class="literal">jetty-alpn-openjdk8-server</code> artifact in the server classpath, providing the ALPN OpenJDK 8 service implementation.</p><p>When using Jetty embedded, the ALPN support is provided by the <code class="literal">jetty-alpn-openjdk8-client</code> and <code class="literal">jetty-alpn-openjdk8-server</code> artifacts, respectively for client usage and server usage.</p><p>To get ALPN working with the Jetty ALPN Boot library, you need:</p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem">to start the JVM with the Jetty ALPN Boot library in the boot classpath</li><li class="listitem">to have the <code class="literal">jetty-alpn-openjdk8-client</code> artifact or the <code class="literal">jetty-alpn-openjdk8-server</code> |
| artifact in the classpath</li></ul></div><p>Start the JVM as follows:</p><pre xmlns:jfetch="java:org.eclipse.jetty.xslt.tools.JavaSourceFetchExtension" xmlns:fetch="java:org.eclipse.jetty.xslt.tools.SourceFetchExtension" xmlns:d="http://docbook.org/ns/docbook" xmlns:l="http://docbook.sourceforge.net/xmlns/l10n/1.0" xmlns:xslthl="http://xslthl.sf.net" xmlns:gcse="http://www.google.com" xmlns:date="http://exslt.org/dates-and-times"><code>java -Xbootclasspath/p:<path_to_alpn_boot_jar> ...</code></pre><p>Where <code class="literal">path_to_alpn_boot_jar</code> is the path on the file system for the <code class="literal">alpn-boot</code> artifact, such as the one at the Maven coordinates <code class="literal">org.mortbay.jetty.alpn:alpn-boot</code>.</p><p>Be certain to get the <a class="link" href="alpn-chapter.html#alpn-versions" title="Versions">ALPN boot artifact version that matches the version of your JRE</a>.</p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="alpn-conscrypt"></a>ALPN and Conscrypt</h3></div></div></div><p>When using JDK 8 or later, you can use the <a class="link" href="https://conscrypt.org/" target="_top">Conscrypt</a> security provider to provide the ALPN service implementation.</p><p>Conscrypt binds natively to BoringSSL (a fork of OpenSSL by Google), so ALPN will be supported via the support provided by BoringSSL (bundled together with Conscrypt).</p><p>When using Jetty as a standalone server via the Jetty distribution, ALPN is enabled by enabling the <code class="literal">conscrypt</code> module.</p><p>When using Jetty embedded, ALPN is enabled by the <code class="literal">jetty-alpn-conscrypt-client</code> and <code class="literal">jetty-alpn-conscrypt-server</code> artifacts, respectively for client usage and server usage. |
| In addition, you also need the Conscrypt artifacts, typically the <code class="literal">org.conscrypt:conscrypt-openjdk-uber</code> artifact. |
| All these artifacts must be added to the classpath.</p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="alpn-jdk9"></a>ALPN and JDK 9</h3></div></div></div><p>When using JDK 9 or later and Jetty as a standalone server via the Jetty distribution, ALPN support is automatically enabled when the <code class="literal">http2</code> module is enabled. |
| This enables transitively the <code class="literal">alpn-9</code> module which puts the <code class="literal">jetty-alpn-java-server</code> artifact in the server classpath, providing the ALPN JDK 9 service implementation.</p><p>When using JDK 9 or later and Jetty embedded, the ALPN service implementation is provided by the <code class="literal">jetty-alpn-java-client</code> and <code class="literal">jetty-alpn-java-server</code> artifacts, respectively for client usage and server usage, and must be added to the classpath.</p><div class="section"><div class="titlepage"><div><div><h4 class="title"><a name="alpn-osgi"></a>Starting in OSGi</h4></div></div></div><p>To use ALPN in an OSGi environment, in addition to what described above, you will also need to deploy the <code class="literal">jetty-osgi-alpn</code> jar. |
| This jar contains a <code class="literal">Fragment-Host</code> directive that ensures the ALPN classes will be available from the system bundle.</p><p>You can download the <a class="link" href="https://repo1.maven.org/maven2/org/eclipse/jetty/osgi/jetty-osgi-alpn/" target="_top">jetty-osgi-alpn jar</a> from Maven Central.</p><div class="blockquote"><blockquote class="blockquote"><div xmlns:jfetch="java:org.eclipse.jetty.xslt.tools.JavaSourceFetchExtension" xmlns:fetch="java:org.eclipse.jetty.xslt.tools.SourceFetchExtension" xmlns:d="http://docbook.org/ns/docbook" xmlns:l="http://docbook.sourceforge.net/xmlns/l10n/1.0" xmlns:xslthl="http://xslthl.sf.net" xmlns:gcse="http://www.google.com" xmlns:date="http://exslt.org/dates-and-times" class="note" style="margin-left: 0.5in; margin-right: 0.5in;"><h3 class="title"><i class="fa fa-asterisk" aria-hidden="true"></i> Note</h3><p>OSGi <span class="strong"><strong>requires</strong></span> a <code class="literal">ServiceLoader</code> implementation for Jetty to function properly. |
| OSGi leverages <a class="link" href="http://aries.apache.org/modules/spi-fly.html" target="_top">Apache Aries SPI Fly</a> for this functionality. |
| You can read more about OSGi and <code class="literal">ServiceLoader</code> <a class="link" href="http://blog.osgi.org/2013/02/javautilserviceloader-in-osgi.html" target="_top">here.</a></p></div></blockquote></div></div></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="alpn-troubleshooting"></a>ALPN Troubleshooting</h3></div></div></div><p>When starting the Jetty server, especially when using Jetty embedded, it may be possible that you see an error similar to this:</p><pre xmlns:jfetch="java:org.eclipse.jetty.xslt.tools.JavaSourceFetchExtension" xmlns:fetch="java:org.eclipse.jetty.xslt.tools.SourceFetchExtension" xmlns:d="http://docbook.org/ns/docbook" xmlns:l="http://docbook.sourceforge.net/xmlns/l10n/1.0" xmlns:xslthl="http://xslthl.sf.net" xmlns:gcse="http://www.google.com" xmlns:date="http://exslt.org/dates-and-times"><code>IllegalStateException: no ALPN processor</code></pre><p>The error means that you don’t have the ALPN dependencies setup correctly in your classpath.</p><p>For example, you may have the <code class="literal">jetty-alpn-java-server</code> artifact in the classpath (which is correct when using JDK 9), but run your application with JDK 8.</p><p>Another example is when you have correctly put the <code class="literal">alpn-boot</code> artifact in the boot classpath, but you don’t have the <code class="literal">jetty-alpn-openjdk8-server</code> artifact in the classpath.</p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="alpn-openjdk8-details"></a>Details about ALPN and OpenJDK 8</h3></div></div></div><p>The following sections only refer to the API and implementation of ALPN using the Jetty boot library.</p><p>The Jetty ALPN boot library is conceptually made of two parts: the ALPN APIs and the ALPN implementation.</p><p>The ALPN API is provided by the <code class="literal">org.eclipse.jetty.alpn:alpn-api</code> artifact. |
| This artifact is only needed by application code that uses the ALPN APIs.</p><p>The ALPN implementation is provided by the <code class="literal">org.mortbay.jetty.alpn:alpn-boot</code> artifact and consist of modifications to the OpenJDK classes. |
| The <code class="literal">org.mortbay.jetty.alpn:alpn-boot</code> artifact contains also the classes present in the <code class="literal">org.eclipse.jetty.alpn:alpn-api</code> artifact.</p><div class="section"><div class="titlepage"><div><div><h4 class="title"><a name="alpn-openjdk8-understanding"></a>Understanding the ALPN API</h4></div></div></div><p>Applications need to interact with ALPN TLS extension protocol negotiations. |
| For example, server applications need to know whether the client supports ALPN, and client applications needs to know whether the server supports ALPN.</p><p>To implement this interaction, Jetty’s ALPN implementation provides an API to applications, hosted at Maven coordinates <code class="literal">org.eclipse.jetty.alpn:alpn-api</code>. |
| You need to declare this dependency as provided, because the <code class="literal">alpn-boot</code> jar already includes it (see the previous section), and it is therefore available from the boot classpath.</p><p>The API consists of a single class, <code class="literal">org.eclipse.jetty.alpn.ALPN</code>, and applications need to register instances of <code class="literal">SSLSocket</code> or <code class="literal">SSLEngine</code> with a <code class="literal">ClientProvider</code> or <code class="literal">ServerProvider</code> (depending on whether the application is a client application or server application). |
| Refer to <code class="literal">ALPN</code> Javadocs and to the examples below for further details about client and server provider methods.</p></div></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="alpn-openjdk8-client-example"></a>Client Example</h3></div></div></div><pre xmlns:jfetch="java:org.eclipse.jetty.xslt.tools.JavaSourceFetchExtension" xmlns:fetch="java:org.eclipse.jetty.xslt.tools.SourceFetchExtension" xmlns:d="http://docbook.org/ns/docbook" xmlns:l="http://docbook.sourceforge.net/xmlns/l10n/1.0" xmlns:xslthl="http://xslthl.sf.net" xmlns:gcse="http://www.google.com" xmlns:date="http://exslt.org/dates-and-times"><code>SSLContext sslContext = ...; |
| SSLSocket sslSocket = (SSLSocket)context.getSocketFactory().createSocket("localhost", server.getLocalPort()); |
| |
| ALPN.put(sslSocket, new ALPN.ClientProvider() |
| { |
| @Override |
| public List<String> protocols() |
| { |
| return Arrays.asList("h2", "http/1.1"); |
| } |
| |
| @Override |
| public void unsupported() |
| { |
| ALPN.remove(sslSocket); |
| } |
| |
| @Override |
| public void selected(String protocol) |
| { |
| ALPN.remove(sslSocket); |
| System.out.println("Protocol Selected is: " + protocol); |
| } |
| });</code></pre><p>The ALPN implementation calls <code class="literal">ALPN.ClientProvider</code> methods <code class="literal">protocols()</code>, <code class="literal">unsupported()</code> and <code class="literal">selected(String)</code>, so that the client application can:</p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem">Decide whether to support ALPN</li><li class="listitem">Provide the protocols supported</li><li class="listitem">Know whether the server supports ALPN</li><li class="listitem">Know the protocol chosen by the server</li></ul></div></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="alpn-openjdk8-server-example"></a>Server Example</h3></div></div></div><p>The example for <code class="literal">SSLEngine</code> is identical, and you just need to replace the <code class="literal">SSLSocket</code> instance with an <code class="literal">SSLEngine</code> instance.</p><pre xmlns:jfetch="java:org.eclipse.jetty.xslt.tools.JavaSourceFetchExtension" xmlns:fetch="java:org.eclipse.jetty.xslt.tools.SourceFetchExtension" xmlns:d="http://docbook.org/ns/docbook" xmlns:l="http://docbook.sourceforge.net/xmlns/l10n/1.0" xmlns:xslthl="http://xslthl.sf.net" xmlns:gcse="http://www.google.com" xmlns:date="http://exslt.org/dates-and-times"><code>SSLEngine sslEngine = ...; |
| ALPN.put(sslEngine, new ALPN.ServerProvider() |
| { |
| @Override |
| public void unsupported() |
| { |
| ALPN.remove(sslEngine); |
| } |
| |
| @Override |
| public String select(List<String> protocols); |
| { |
| ALPN.remove(sslEngine); |
| return protocols.get(0); |
| } |
| });</code></pre><p>The ALPN implementation calls <code class="literal">ALPN.ServerProvider</code> methods <code class="literal">unsupported()</code>, and <code class="literal">select(List<String>),</code> so that the server application can:</p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem">know whether the client supports ALPN.</li><li class="listitem">select one of the protocols the client supports.</li></ul></div></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="alpn-openjdk8-implementation"></a>Implementation Details</h3></div></div></div><p>It is important that implementations of <code class="literal">ALPN.ServerProvider</code> and <code class="literal">ALPN.ClientProvider</code> remove the <code class="literal">sslSocket</code> or <code class="literal">sslEngine</code> when the negotiation is complete, like shown in the examples above. |
| Failing to do so will cause a memory leak.</p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="alpn-openjdk8-tests"></a>Unit Tests</h3></div></div></div><p>You can write and run unit tests that use the ALPN implementation. |
| The solution that we use with Maven is to specify an additional command line argument to the Surefire plugin:</p><pre xmlns:jfetch="java:org.eclipse.jetty.xslt.tools.JavaSourceFetchExtension" xmlns:fetch="java:org.eclipse.jetty.xslt.tools.SourceFetchExtension" xmlns:d="http://docbook.org/ns/docbook" xmlns:l="http://docbook.sourceforge.net/xmlns/l10n/1.0" xmlns:xslthl="http://xslthl.sf.net" xmlns:gcse="http://www.google.com" xmlns:date="http://exslt.org/dates-and-times"><code><project> |
| |
| <properties> |
| <alpn-boot-version>8.1.4.v20150727</alpn-boot-version> |
| </properties> |
| |
| <build> |
| <plugins> |
| <plugin> |
| <artifactId>maven-surefire-plugin</artifactId> |
| <configuration> |
| <argLine> |
| -Xbootclasspath/p:${settings.localRepository}/org/mortbay/jetty/alpn/alpn-boot/${alpn-boot-version}/alpn-boot-${alpn-boot-version}.jar |
| </argLine> |
| </configuration> |
| </plugin> |
| |
| ... |
| |
| </plugins> |
| </build> |
| |
| ... |
| |
| </project></code></pre></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="alpn-openjdk8-debugging"></a>Debugging</h3></div></div></div><p>You can enable debug logging for the ALPN implementation in this way:</p><pre class="literallayout">ALPN.debug = true;</pre><p>Since the ALPN class is in the boot classpath, we chose not to use logging libraries because we do not want to override application logging library choices; therefore the logging is performed directly on <code class="literal">System.err</code>.</p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="alpn-openjdk8-license-details"></a>License Details</h3></div></div></div><p>The ALPN implementation relies on modification of a few OpenJDK classes and on a few new classes that need to live in the <code class="literal">sun.security.ssl</code> package. |
| These classes are released under the same <code class="literal">GPLv2+exception</code> license of OpenJDK.</p><p>The ALPN class and its nested classes are released under same license as the classes of the Jetty project.</p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="alpn-versions"></a>Versions</h3></div></div></div><p>The ALPN implementation, relying on modifications of OpenJDK classes, updates every time there are updates to the modified OpenJDK classes.</p><div class="table"><a name="d0e17910"></a><p class="title"><b>Table 15.1. ALPN vs. OpenJDK versions</b></p><div class="table-contents"><table class="table" summary="ALPN vs. OpenJDK versions" border="1"><colgroup><col class="col_1"><col class="col_2"></colgroup><thead><tr><th align="left" valign="top">OpenJDK version</th><th align="left" valign="top">ALPN version</th></tr></thead><tbody><tr><td align="left" valign="top"><p>1.7.0u40</p></td><td align="left" valign="top"><p>7.1.0.v20141016</p></td></tr><tr><td align="left" valign="top"><p>1.7.0u45</p></td><td align="left" valign="top"><p>7.1.0.v20141016</p></td></tr><tr><td align="left" valign="top"><p>1.7.0u51</p></td><td align="left" valign="top"><p>7.1.0.v20141016</p></td></tr><tr><td align="left" valign="top"><p>1.7.0u55</p></td><td align="left" valign="top"><p>7.1.0.v20141016</p></td></tr><tr><td align="left" valign="top"><p>1.7.0u60</p></td><td align="left" valign="top"><p>7.1.0.v20141016</p></td></tr><tr><td align="left" valign="top"><p>1.7.0u65</p></td><td align="left" valign="top"><p>7.1.0.v20141016</p></td></tr><tr><td align="left" valign="top"><p>1.7.0u67</p></td><td align="left" valign="top"><p>7.1.0.v20141016</p></td></tr><tr><td align="left" valign="top"><p>1.7.0u71</p></td><td align="left" valign="top"><p>7.1.2.v20141202</p></td></tr><tr><td align="left" valign="top"><p>1.7.0u72</p></td><td align="left" valign="top"><p>7.1.2.v20141202</p></td></tr><tr><td align="left" valign="top"><p>1.7.0u75</p></td><td align="left" valign="top"><p>7.1.3.v20150130</p></td></tr><tr><td align="left" valign="top"><p>1.7.0u76</p></td><td align="left" valign="top"><p>7.1.3.v20150130</p></td></tr><tr><td align="left" valign="top"><p>1.7.0u79</p></td><td align="left" valign="top"><p>7.1.3.v20150130</p></td></tr><tr><td align="left" valign="top"><p>1.7.0u80</p></td><td align="left" valign="top"><p>7.1.3.v20150130</p></td></tr><tr><td align="left" valign="top"><p>1.8.0</p></td><td align="left" valign="top"><p>8.1.0.v20141016</p></td></tr><tr><td align="left" valign="top"><p>1.8.0u05</p></td><td align="left" valign="top"><p>8.1.0.v20141016</p></td></tr><tr><td align="left" valign="top"><p>1.8.0u11</p></td><td align="left" valign="top"><p>8.1.0.v20141016</p></td></tr><tr><td align="left" valign="top"><p>1.8.0u20</p></td><td align="left" valign="top"><p>8.1.0.v20141016</p></td></tr><tr><td align="left" valign="top"><p>1.8.0u25</p></td><td align="left" valign="top"><p>8.1.2.v20141202</p></td></tr><tr><td align="left" valign="top"><p>1.8.0u31</p></td><td align="left" valign="top"><p>8.1.3.v20150130</p></td></tr><tr><td align="left" valign="top"><p>1.8.0u40</p></td><td align="left" valign="top"><p>8.1.3.v20150130</p></td></tr><tr><td align="left" valign="top"><p>1.8.0u45</p></td><td align="left" valign="top"><p>8.1.3.v20150130</p></td></tr><tr><td align="left" valign="top"><p>1.8.0u51</p></td><td align="left" valign="top"><p>8.1.4.v20150727</p></td></tr><tr><td align="left" valign="top"><p>1.8.0u60</p></td><td align="left" valign="top"><p>8.1.5.v20150921</p></td></tr><tr><td align="left" valign="top"><p>1.8.0u65</p></td><td align="left" valign="top"><p>8.1.6.v20151105</p></td></tr><tr><td align="left" valign="top"><p>1.8.0u66</p></td><td align="left" valign="top"><p>8.1.6.v20151105</p></td></tr><tr><td align="left" valign="top"><p>1.8.0u71</p></td><td align="left" valign="top"><p>8.1.7.v20160121</p></td></tr><tr><td align="left" valign="top"><p>1.8.0u72</p></td><td align="left" valign="top"><p>8.1.7.v20160121</p></td></tr><tr><td align="left" valign="top"><p>1.8.0u73</p></td><td align="left" valign="top"><p>8.1.7.v20160121</p></td></tr><tr><td align="left" valign="top"><p>1.8.0u74</p></td><td align="left" valign="top"><p>8.1.7.v20160121</p></td></tr><tr><td align="left" valign="top"><p>1.8.0u77</p></td><td align="left" valign="top"><p>8.1.7.v20160121</p></td></tr><tr><td align="left" valign="top"><p>1.8.0u91</p></td><td align="left" valign="top"><p>8.1.7.v20160121</p></td></tr><tr><td align="left" valign="top"><p>1.8.0u92</p></td><td align="left" valign="top"><p>8.1.8.v20160420</p></td></tr><tr><td align="left" valign="top"><p>1.8.0u101</p></td><td align="left" valign="top"><p>8.1.9.v20160720</p></td></tr><tr><td align="left" valign="top"><p>1.8.0u102</p></td><td align="left" valign="top"><p>8.1.9.v20160720</p></td></tr><tr><td align="left" valign="top"><p>1.8.0u111</p></td><td align="left" valign="top"><p>8.1.9.v20160720</p></td></tr><tr><td align="left" valign="top"><p>1.8.0u112</p></td><td align="left" valign="top"><p>8.1.10.v20161026</p></td></tr><tr><td align="left" valign="top"><p>1.8.0u121</p></td><td align="left" valign="top"><p>8.1.11.v20170118</p></td></tr><tr><td align="left" valign="top"><p>1.8.0u131</p></td><td align="left" valign="top"><p>8.1.11.v20170118</p></td></tr><tr><td align="left" valign="top"><p>1.8.0u141</p></td><td align="left" valign="top"><p>8.1.11.v20170118</p></td></tr><tr><td align="left" valign="top"><p>1.8.0u144</p></td><td align="left" valign="top"><p>8.1.11.v20170118</p></td></tr><tr><td align="left" valign="top"><p>1.8.0u151</p></td><td align="left" valign="top"><p>8.1.11.v20170118</p></td></tr><tr><td align="left" valign="top"><p>1.8.0u152</p></td><td align="left" valign="top"><p>8.1.11.v20170118</p></td></tr><tr><td align="left" valign="top"><p>1.8.0u161</p></td><td align="left" valign="top"><p>8.1.12.v20180117</p></td></tr><tr><td align="left" valign="top"><p>1.8.0u162</p></td><td align="left" valign="top"><p>8.1.12.v20180117</p></td></tr><tr><td align="left" valign="top"><p>1.8.0u171</p></td><td align="left" valign="top"><p>8.1.12.v20180117</p></td></tr><tr><td align="left" valign="top"><p>1.8.0u172</p></td><td align="left" valign="top"><p>8.1.12.v20180117</p></td></tr><tr><td align="left" valign="top"><p>1.8.0u181</p></td><td align="left" valign="top"><p>8.1.12.v20180117</p></td></tr><tr><td align="left" valign="top"><p>1.8.0u191</p></td><td align="left" valign="top"><p>8.1.13.v20181017</p></td></tr><tr><td align="left" valign="top"><p>1.8.0u192</p></td><td align="left" valign="top"><p>8.1.13.v20181017</p></td></tr><tr><td align="left" valign="top"><p>1.8.0u201</p></td><td align="left" valign="top"><p>8.1.13.v20181017</p></td></tr><tr><td align="left" valign="top"><p>1.8.0u202</p></td><td align="left" valign="top"><p>8.1.13.v20181017</p></td></tr><tr><td align="left" valign="top"><p>1.8.0u211<sup>[1]</sup></p></td><td align="left" valign="top"><p>8.1.13.v20181017</p></td></tr><tr><td align="left" valign="top"><p>1.8.0u212</p></td><td align="left" valign="top"><p>8.1.13.v20181017</p></td></tr><tr><td align="left" valign="top"><p>1.8.0u221<sup>[1]</sup></p></td><td align="left" valign="top"><p>8.1.13.v20181017</p></td></tr><tr><td align="left" valign="top"><p>1.8.0u222</p></td><td align="left" valign="top"><p>8.1.13.v20181017</p></td></tr><tr><td align="left" valign="top"><p>1.8.0u231<sup>[1]</sup></p></td><td align="left" valign="top"><p>8.1.13.v20181017</p></td></tr><tr><td align="left" valign="top"><p>1.8.0u232</p></td><td align="left" valign="top"><p>8.1.13.v20181017</p></td></tr><tr><td align="left" valign="top"><p>1.8.0u241<sup>[1]</sup></p></td><td align="left" valign="top"><p>8.1.13.v20181017</p></td></tr><tr><td align="left" valign="top"><p>1.8.0u242</p></td><td align="left" valign="top"><p>8.1.13.v20181017</p></td></tr></tbody></table></div></div><br class="table-break"><p><sup>[1]</sup> These are Oracle releases for which the source code is not available, |
| or it is unclear what exactly is because there is no correspondent tag in |
| the OpenJDK repository. |
| We assume that the source code for these releases is equivalent (at least |
| for the files modified to make ALPN work) to the release that follows |
| (for example, for 1.8.0u211 we assume that the source code is equivalent |
| to 1.8.0u212, for 1.8.0u221 we assume 1.8.0u222, etc.).</p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="alpn-build"></a>How to build ALPN</h3></div></div></div><p>This section is for Jetty developers that need to update the ALPN implementation with the OpenJDK versions.</p><p>Clone the OpenJDK repository with the following command:</p><div class="screenexample"><pre class="screen">$ hg clone https://hg.openjdk.java.net/jdk8u/jdk8u jdk8u |
| $ cd !$ |
| $ ./get_source.sh</pre></div><p>To update the source to a specific tag, use the following command:</p><div class="screenexample"><pre class="screen">$ ./make/scripts/hgforest.sh update <tag-name></pre></div><p>The list of OpenJDK tags can be obtained from this page: |
| <a class="link" href="https://hg.openjdk.java.net/jdk8u/jdk8u/tags" target="_top">OpenJDK 8 Tags</a>.</p><p>You will then need to compare and incorporate the OpenJDK source changes into the modified OpenJDK classes at the <a class="link" href="https://github.com/jetty-project/jetty-alpn" target="_top">ALPN GitHub Repository</a>, branch <code class="literal">master</code>.</p></div></div></div><script type="text/javascript"> |
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