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  <h1>JMRI: Java Version-Specific Features (Older Page)</h1>
      <p>This is the "historical page" for 
      the <a href="JVMCapabilities.shtml">Java Version-Specific Features</a> page.

      
      <h2>Capabilities</h2>
      <p>This section lists new Java
      capabilities, and which Java version they first appeared in.
      The "JDK" column shows the first Java Development Kit that
      could compile the feature; the "JRE" column lists the first
      runtime environment that could run the feature, including the
      needed JVM and library support.

      <table border="1">
        <tr>
          <th>Feature</th>

          <th>JDK</th>

          <th>JRE</th>
        </tr>

        <tr>
          <td>HiDPI graphics support for Windows and Linux users.
          Probably "just works" with JRE update, unless something
          in JMRI breaks on Java 9 on Windows (Currently support
          using very large fonts as a workaround, but it quickly
          breaks as text overlaps widget boundaries)</td>

          <td>1.8?</td>

          <td>1.9</td>
        </tr>

        <tr>
          <td>It seems that MacOS X (macOS) users will lose the use
          of the OS X App menu for About, Preferences, and
          (critically) Quit handling on that platform</td>

          <td>1.9</td>

          <td>1.9</td>
        </tr>

        <tr>
          <td>It seems that MacOS X (macOS) users will lose
          Applescript scripting</td>

          <td>1.9</td>

          <td>1.9</td>
        </tr>

        <tr>
          <td>Generics for Swing classes</td>

          <td>1.7</td>

          <td>1.7</td>
        </tr>

        <tr>
          <td>NIO improves .zip file access</td>

          <td>1.7</td>

          <td>1.7</td>
        </tr>

        <tr>
          <td>I18N I/O improvements</td>

          <td>1.7</td>

          <td>1.7</td>
        </tr>

        <tr>
          <td>Memory use and<br>
          GC improvements<br>
          (better performance)</td>

          <td>1.7</td>

          <td>1.7</td>
        </tr>

        <tr>
          <td>Jetty Version 9</td>

          <td>1.7</td>

          <td>1.7</td>
        </tr>

        <tr>
          <td>JUnit 4 and the<br>
          <code>assert</code> keyword</td>

          <td>1.7</td>

          <td>1.7</td>
        </tr>

        <tr>
          <td>Desktop class</td>

          <td>1.6</td>

          <td>1.6</td>
        </tr>

        <tr>
          <td>JDOM2 (generics)</td>

          <td>1.6</td>

          <td>1.6</td>
        </tr>

        <tr>
          <td>Toolbars</td>

          <td>1.6</td>

          <td>1.6</td>
        </tr>

        <tr>
          <td>JTable Sorting</td>

          <td>1.6</td>

          <td>1.6</td>
        </tr>

        <tr>
          <td>Webstart compatibility</td>

          <td>1.6</td>

          <td>1.6</td>
        </tr>

        <tr>
          <td>SwingWorker</td>

          <td>1.5</td>

          <td>1.5 (*1.4)</td>
        </tr>

        <tr>
          <td>JSpinner</td>

          <td>1.5</td>

          <td>1.5</td>
        </tr>

        <tr>
          <td>Enums</td>

          <td>1.5</td>

          <td>1.5</td>
        </tr>

        <tr>
          <td>printf, Formatter</td>

          <td>1.5</td>

          <td>1.5</td>
        </tr>

        <tr>
          <td>generics</td>

          <td>1.5</td>

          <td>1.5</td>
        </tr>

        <tr>
          <td>Annotations</td>

          <td>1.5</td>

          <td>1.3</td>
        </tr>

        <tr>
          <td>JavaMail</td>

          <td>1.5</td>

          <td>1.3</td>
        </tr>

        <tr>
          <td>JUnit 4.0</td>

          <td>1.5</td>

          <td>1.3</td>
        </tr>

        <tr>
          <td>JDOM 1.0</td>

          <td>1.4</td>

          <td>1.3</td>
        </tr>

        <tr>
          <td>Java regexp</td>

          <td>1.4</td>

          <td>1.4</td>
        </tr>

        <tr>
          <td>Java3D</td>

          <td>1.4</td>

          <td>1.4</td>
        </tr>

        <tr>
          <td>JavaHelp update</td>

          <td>1.4</td>

          <td>1.4</td>
        </tr>

        <tr>
          <td>Drag and Drop</td>

          <td>1.4 (additional<br>
          improvements in 1.6)</td>

          <td>1.4, 1.6</td>
        </tr>

        <tr>
          <td>Logging API</td>

          <td>1.4 (additional<br>
          improvements in 1.6)</td>

          <td>1.4, 1.6</td>
        </tr>

        <tr>
          <td>XML catalog resolver</td>

          <td>1.3?</td>

          <td>1.4?</td>
        </tr>

        <tr>
          <td>Collections</td>

          <td>1.3</td>

          <td>1.3</td>
        </tr>

        <tr>
          <td>Java2D</td>

          <td>1.3</td>

          <td>1.3</td>
        </tr>

        <tr>
          <td>Printing update</td>

          <td>1.3</td>

          <td>1.3</td>
        </tr>

        <tr>
          <td>JUnit 3.8</td>

          <td>1.3</td>

          <td>1.3</td>
        </tr>
      </table>(* indicates that a compatibility library is used in
      the early version)

      <h2>JRE availability</h2>
      <p>This section lists the most recent
      Java Runtime version available for various operating system
      versions. Please note that not all users of that operating
      system will have updated to this Java version; many will be
      using an older one.

      <p><a href=
      "http://www.oracle.com/technetwork/java/javase/config-417990.html">
      Oracle's page on Java 1.7 requirements</a> which says "Note:
      As of April 8, 2014 Microsoft stopped supporting Windows XP
      and therefore it is no longer a supported platform." Google
      finds numerous pages that show how to install Java 1.7 on XP
      or XP SP2.</p>

      <table border="1">
        <tr>
          <th>OS and platform</th>

          <th>Last JRE</th>
        </tr>

        <tr>
          <td>Linux</td>

          <td>(depends?)</td>
        </tr>

        <tr>
          <td>Win 8 (32-bit)</td>

          <td>1.8</td>
        </tr>

        <tr>
          <td>Win 7 (32-bit)</td>

          <td>1.8</td>
        </tr>

        <tr>
          <td>Win Vista (32-bit)</td>

          <td>1.8</td>
        </tr>

        <tr>
          <td>Win Server 2008 (32-bit)</td>

          <td>1.8</td>
        </tr>

        <tr>
          <td>Win Web Server 2008 (32-bit)</td>

          <td>1.6</td>
        </tr>

        <tr>
          <td>Win 2000 (32-bit)</td>

          <td>1.6</td>
        </tr>

        <tr>
          <td>Win Server 2003 (32-bit)</td>

          <td>1.6</td>
        </tr>

        <tr>
          <td>Win 8 (64-bit)</td>

          <td>1.8</td>
        </tr>

        <tr>
          <td>Win Server 2012 (64-bit)</td>

          <td>1.8</td>
        </tr>

        <tr>
          <td>Win Server 2012 R2 (64-bit)</td>

          <td>1.8</td>
        </tr>

        <tr>
          <td>Win 7 (64-bit)</td>

          <td>1.8</td>
        </tr>

        <tr>
          <td>Win Server 2008 R2 (64-bit)</td>

          <td>1.8</td>
        </tr>

        <tr>
          <td>Win Server 2008 (64-bit)</td>

          <td>1.7</td>
        </tr>

        <tr>
          <td>Win Web Server 2008 R2 (64-bit)</td>

          <td>1.6</td>
        </tr>

        <tr>
          <td>Win Vista (64-bit)</td>

          <td>1.8</td>
        </tr>

        <tr>
          <td>Win 2003 (64-bit)</td>

          <td>1.6</td>
        </tr>

        <tr>
          <td>Windows XP</td>

          <td>1.8<br>
          <a href=
          "https://www.java.com/en/download/faq/winxp.xml">Unofficial<br>

          Support</a></td>
        </tr>

        <tr>
          <td>Windows 98 (2nd Ed)</td>

          <td>1.5-11</td>
        </tr>

        <tr>
          <td>Windows 98</td>

          <td>1.4.2_14</td>
        </tr>

        <tr>
          <td>Windows 95</td>

          <td>1.3.1_20</td>
        </tr>

        <tr>
          <td>Mac OS X 10.8.3 and later on Intel</td>

          <td>1.8</td>
        </tr>

        <tr>
          <td>Mac OS X 10.7.3 and later on Intel</td>

          <td>1.7</td>
        </tr>

        <tr>
          <td>Mac OS X 10.5.8 and later on Intel</td>

          <td>1.6 (Apple JVM)</td>
        </tr>

        <tr>
          <td>Mac OS X 10.5.7 and earlier on Intel</td>

          <td>1.5 (Apple JVM)</td>
        </tr>

        <tr>
          <td>Mac OS X 10.3 and later on PowerPC</td>

          <td>1.5 (Apple JVM)</td>
        </tr>

        <tr>
          <td>MacOS "Classic"</td>

          <td>1.1.8</td>
        </tr>

        <tr>
          <td>OS/2</td>

          <td>1.3</td>
        </tr>
      </table>

      <p>See the <a href=
      "http://java.com/en/download/manual.jsp">Java.com download
      page for all Operating Systems</a> and<br>
      information on <a href=
      "https://www.java.com/en/download/help/sysreq.xml">Java
      versions and hardware requirements</a>.</p>

      <h2 id="sysreq">System Requirements</h2>

      <p>The following combination of JMRI - Java - Platform/OS
      versions was based on Oracle and OS developers sources. It's
      translated to the OS install instructions (follow hyperlink
      in OS headers):</p>

      <table border="1">
        <tbody>
          <tr>
            <th>JMRI</th>

            <th>Java</th>

            <th><a href=
            "https://jmri.org/install/MacOSX.shtml#sysreq">OS
            X</a></th>

            <th><a href=
            "https://jmri.org/install/WindowsNew.shtml#sysreq">Windows</a></th>

            <th><a href=
            "https://jmri.org/install/Linux.shtml#sysreq">Linux</a></th>

            <th><a href=
            "https://jmri.org/install/Ubuntu.shtml#sysreq">Ubuntu</a></th>

            <th><a href=
            "https://jmri.org/install/Raspbian.shtml#sysreq">Raspbian</a></th>
          </tr>

          <tr>
            <td>4.2</td>

            <td>1.8</td>

            <td>10.8.3+ Mountain Lion</td>

            <td>Win7 SP1/8/10, Vista SP2, (XP)</td>

            <td>5.5+</td>

            <td>12.04+</td>

            <td>14.04LTS</td>
          </tr>

          <tr>
            <td>3.10.1</td>

            <td>1.7</td>

            <td>10.7.3 Lion</td>

            <td>Win7 SP1/8/10, Vista SP2, (XP)</td>

            <td>5.5+</td>

            <td>12.04</td>

            <td>12.04</td>
          </tr>

          <tr>
            <td>3.10.1</td>

            <td>1.6</td>

            <td>10.6 Snow Leopard (JVM6)</td>

            <td>Win2003, Win2000 (x86)</td>

            <td>5.5</td>

            <td>10.4</td>

            <td>N/A</td>
          </tr>

          <tr>
            <td>2.14.1</td>

            <td>1.5</td>

            <td>10.5.7 Leopard (JVM5)</td>

            <td>Vista SP1, Win2000 SP3, Win8.x (x64)</td>

            <td></td>

            <td>9.04</td>

            <td>N/A</td>
          </tr>

          <tr>
            <td>2.8</td>

            <td>1.5</td>

            <td>10.4 Tiger</td>

            <td>Win98 (2nd Ed), XP, ME</td>

            <td></td>

            <td></td>

            <td>N/A</td>
          </tr>

          <tr>
            <td>2.2</td>

            <td>1.5</td>

            <td>10.3 Panther</td>

            <td>Win98, ME</td>

            <td>N/A</td>

            <td>N/A</td>

            <td>N/A</td>
          </tr>

          <tr>
            <td></td>

            <td>1.3.1</td>

            <td>10.3 Panther</td>

            <td>Win95, Win98</td>

            <td>N/A</td>

            <td>N/A</td>

            <td>N/A</td>
          </tr>

          <tr>
            <td>1.6</td>

            <td>1.1.8</td>

            <td>MacOS9.1 (MRJ)</td>

            <td>Win95, Win98</td>

            <td>N/A</td>

            <td>N/A</td>

            <td>N/A</td>
          </tr>
        </tbody>
      </table>

      <h2 id="JDK8">Moving to Java 1.8 from 1.6</h2>This section
      discusses, roughly in order of decreasing importance, the
      process of migrating from Java 1.6 to Java 1.8.

      <h3>Generics, Swing and JComboBox</h3>Java 1.8 introduces
      generics for Swing objects. The most common one is JComboBox.
      This Java 1.6 line:
      <pre style="font-family: monospace;">
    JComboBox box = new JComboBox();
</pre>describes the creation of a JComboBox that selects generic
(Object) items.<br>
      In Java 1.8, the JComboBox holds and selects objects of a
      specific type, usually String. It's written:
      <pre style="font-family: monospace;">
    JComboBox&lt;String&gt; box = new JComboBox&lt;&gt;();
</pre>The most common code for getting the selected item still
includes a cast:
      <pre style="font-family: monospace;">
    String result = (String)box.getSelectedItem();
</pre>because the JComboBox can actually contain objects of other
types (How can this happen? If the box is editable, and somebody
enters some other type).<br>
      To avoid the case, a more robust idiom is:
      <pre style="font-family: monospace;">
    String result = box.getItemAt(progBox.getSelectedIndex());
</pre>

      <h3>Javadoc and doclint</h3>Java 1.8 by default runs the
      <a href=
      "https://docs.oracle.com/javase/8/docs/technotes/tools/unix/javadoc.html#CHDFDACB">
      doclint</a> doclet when making Javadoc. By default, it is
      <a href=
      "http://blog.joda.org/2014/02/turning-off-doclint-in-jdk-8-javadoc.html">
      very aggressive</a> on possible errors. The default Ant-based
      builds turn off some of the checking terms with
      <pre style="font-family: monospace;">
-Xdoclint:all,-missing,-accessibility,-html,-syntax
</pre>to drop tests for missing Javadoc tags and certain benign
HTML errors. (For now) <a name="extension" id="extension"></a>

      <h2>JVM and JDK Extensions</h2>It's possible to extend the
      JVM and/or JDK installed on your machine via <a href=
      "http://docs.oracle.com/javase/8/docs/technotes/guides/standards/index.html">
      the endorsed-standards override mechanism</a> and the
      <a href="http://docs.oracle.com/javase/8/docs/technotes/guides/extensions/index.html">
      extension mechanism</a>. Those extensions, if present, take
      precedence over code shipped with applications like JMRI.
      Unfortunately, these can cause problems if the installed
      extensions interfere with a JMRI component. For example, an
      older (or younger) version might not be compatible, etc. It
      is very unusual for this to cause a problem with JMRI. You
      should investigate other possible causes before looking into
      this one! To check for this, execute the following from the
      command line: <code>java -XX:+CheckEndorsedAndExtDirs</code>
      If you get a message about a specific directory, look there
      for conflicting Jar files. You should probably consult the
      JMRIusers or jmri-developers mailing list for help before
      changing that directory! <!--#include virtual="/Footer.shtml" -->
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