XAM Canonical Format

One of the key requirements for achieving long term data persistence is the ability to move data between archiving systems or, in the language of the SNIA XAM (eXtensible Access Method) specification, moving XSets between XSystems.

The XAM v1.0 specification supports this requirement by providing support for exporting and importing Xsets.  It specifies the methods used to export an XSet from an XSystem, the resultant XSet canonical data interchange format (package) and the methods used to import an Xset into an Xsystem. 

This post assumes that you are somewhat familiar with XAM and how to program to that specification using Java.  It focuses on the format and content of the XSet canonical format package which consists of two main parts: an XML document which describes the policies, properties and streams of one or more XSets followed by the binary representation of the stream(s).

The package format conforms to the 2005 W3C XML-binary Optimized Packaging (XOP) recommendation. To quote from the recommendation:

XOP define a general purpose serialization mechanism for the XML Infoset with binary content that is not only applicable to SOAP and MIME packaging, but to any XML Infoset and any packaging mechanism.

If you are unfamiliar with XOP, and most people are, an article by Andrey Butov in the December 2005 issue of Doctor Dobb's Journal contained a good introduction.

More than one XSet can be contained in a package.  However the current XAM SDK reference implementation only supports one XSet.  The XML document (AKA the XSet manifest) is a valid and well-formed XML document whose root element is xsets.  It can be parsed and manipulated using XSLT and other XML tools.  Annex B of the XAM Architecture document contains an XML Schema Definition (XSD) for the XSet manifest.

In order to study the package format in more detail, I wrote a small Java application called StoreHelloWorld which creates a new XSet containing two XStreams.  The first Xstream contains the source code for the ubiquitous HelloWorld.java program.  The second XStream contains the binary object HelloWorld.class encoded to base64 and with a MIME type of application/base64.  Normally you should not encode an XStream but displaying binary files in a blog is problematic and hence the workaround.

Here is the source code for StoreHelloWorld.

import java.io.BufferedOutputStream;
import java.io.BufferedInputStream;
import java.io.BufferedReader;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.FileNotFoundException;
import java.io.FileWriter;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.InputStream;
import java.util.Calendar;

import org.snia.xam.XAMException;
import org.snia.xam.XAMLibrary;
import org.snia.xam.XSet;
import org.snia.xam.XStream;
import org.snia.xam.XSystem;
import org.snia.xam.XUID;
import org.snia.xam.util.XAMLibraryFactory;

public class StoreHelloWorld {
   private static XAMLibrary xamLib;
   private static XSystem xSystem;
   private static final int BUFFER_SIZE = 1024 * 128;

    private static XUID storeExportFile(String filename) throws XAMException {
        XUID xuid = null;

        System.out.println("Create XSet ....");
        XSet xSet = xSystem.createXSet(XSet.MODE_UNRESTRICTED);
        xSet.createProperty("app.filename", true, "HelloWorld.");

        try {
            System.out.println("Create XStream 1 ....");
            BufferedInputStream inputStream = new BufferedInputStream(new FileInputStream("HelloWorld.java"));
            XStream xStream = xSet.createXStream("com.rhc.file.source", true, XAMLibrary.DEFAULT_MIME_TYPE);

            byte[] buffer = new byte[BUFFER_SIZE];
            long bytesRead = 0;

            while((bytesRead = inputStream.read(buffer)) > 0) {
                long bytesPos = 0;
                while(bytesPos < bytesRead) {
                    long bytesWrite = xStream.write(buffer, bytesPos, bytesRead - bytesPos);
                    bytesPos += bytesWrite;
                }
            }
            inputStream.close();
            xStream.close();
        } catch (FileNotFoundException fe) {
            throw new IllegalArgumentException("Could not open HelloWorld.java for reading");
        } catch (IOException ioe) {
            System.err.println("Error reading from HelloWorld.java");
            ioe.printStackTrace();
        }

        try {
            System.out.println("Create XStream 2 ....");

            InputStream inputStream = new Base64.InputStream(new FileInputStream("HelloWorld.class"), Base64.ENCODE | Base64.DO_BREAK_LINES);
            XStream xStream = xSet.createXStream("com.rhc.file.binary", true, "application/base64");

            byte[] buffer = new byte[BUFFER_SIZE];
            long bytesRead = 0;

            while((bytesRead = inputStream.read(buffer)) > 0) {
                long bytesPos = 0;
                while(bytesPos < bytesRead) {
                    long bytesWrite = xStream.write(buffer, bytesPos, bytesRead - bytesPos);
                    bytesPos += bytesWrite;
                }
            }
            inputStream.close();
            xStream.close();
        } catch (FileNotFoundException fe) {
            throw new IllegalArgumentException("Could not open HelloWorld.class for reading");
        } catch (IOException ioe) {
            System.err.println("Error reading from HelloWorld.class");
            ioe.printStackTrace();
        }

       System.out.println("Commit XSet .... ");
       xuid = xSet.commit();
       System.out.println("Assigned XUID: " + xuid.toString());

       System.out.println("Close XSet .... ");
       xSet.close();

       File saveFile = new File(filename);
       try {
           System.out.println("\nOpen XSet .... ");
           xSet = xSystem.openXSet(xuid, XSet.MODE_READ_ONLY);

           BufferedOutputStream outputStream = new BufferedOutputStream(new FileOutputStream(saveFile));

           System.out.println("Open XStream for export ....");
           XStream xStream = xSet.openExportXStream();

           byte[] buffer = new byte[BUFFER_SIZE];
           long bytesRead = 0;

           System.out.println("Retrieve data .... ");
           while((bytesRead = xStream.read(buffer)) > 0) {
               outputStream.write(buffer, 0, (int)bytesRead);
           }
           xStream.close();
           outputStream.close();

           System.out.println("Close XSet .... ");
           xSet.close();
        } catch (IOException ioe) {
            System.err.println("Error writing to " + saveFile);
            ioe.printStackTrace();
        }

        return (xuid);
   }
 
   public static void main(String[] args) {
       String xri = XRIstring.get();
       long exitCode = 0;

       InputStreamReader inputReader = new InputStreamReader(System.in);
       BufferedReader stdin = new BufferedReader(inputReader);

       try {
           xamLib = XAMLibraryFactory.newXAMLibrary();

           if (xri == null ) {
               System.out.print("Enter Xsystem address: ");
               String answer = stdin.readLine();
               if (!answer.equals(""))
                  xri = answer;
               else
                  System.exit(0);
           }

           System.out.println("Connecting to XSystem: " + xri );
           xSystem = xamLib.connect(xri);

           System.out.print("Name of export file: ");
           String filename = stdin.readLine();
           if (filename.equals(""))
               System.exit(0);

           XUID xuid = storeExportFile(filename);

           xSystem.close();
           System.out.println("\nClosed connection to XSystem");

           inputReader.close();
           stdin.close();

       } catch (XAMException xe) {
           exitCode = xe.getStatusCode();
           System.err.println(
               "XAM Error occured: " + xe.getMessage() + "(" + exitCode + ")");
       } catch (IOException e) {
           System.out.println("I/O Error occurred: " + e.getMessage());
           e.printStackTrace();
           exitCode = 1;
       } catch (IllegalArgumentException e) {
           System.out.println(e.getMessage());
           e.printStackTrace();
           exitCode = 1;
       }

       System.exit((int) exitCode);
   }
}

Rather than hard code an XRI (XAM Resource Identifier) in each XAM application, I use a separate Java class (XRIstring) to read in the XRI from the standard XAM properties file xam.properties.

I know that this is not kosher according to the current XAM specification but, in my humble opinion, this is the natural location for storing this string as most people will not be connecting simultaneously to multiple XSystems.

Here is the source for that Java class.

import java.io.FileInputStream;
import java.io.IOException;
import java.io.FileNotFoundException;
import java.util.Properties;

public class XRIstring
{
   private static Properties props;
   private static String XRI = ".xam.config.xri";
   private static String xri = null;

   static {

       props = new Properties();
       try {
           props.load(new FileInputStream("xam.properties"));

           xri = props.getProperty(XRI);
           if (xri != null)
               System.out.println("XSystem Address: " + xri );

       } catch (FileNotFoundException e) {
          System.err.println("Could not find properties file. XSystem address must be manually entered");
       } catch (IOException e) {
          System.err.println("Could not access properties file. XSystem address must be manually entered");
       }
   }

   public static String get()
   {
        return(xri);
   }
}

This application also uses Robert Harder's popular Base64 class which is available here.  Assuming your CLASSPATH is set up correctly to find the XAM libraries, here is the output from StoreHelloWorld when you build and run it.

$ javac StoreHelloWorld.java XRIstring.java Base64.java

$ java StoreHelloWorld
Connecting to XSystem: snia-xam://centera_vim!XXX.XXX.XXX.XXX?/home/fpm/xam/xamconnect.pea
Name of export file: sample
Create XSet ....
Create XStream 1 ....
Create XStream 2 ....
Commit XSet ....
Assigned XUID: AAAEcwA9S8c0UTVHVDdRSDRSUU9VZUVWMkEyTTJGUUw2UUlHNDE0N1ZTMzFKTzFURkxWUjVKNkFDVEo2Ng==
Close XSet ....

Open XSet for export ....
Retrieve data ....
Close XSet ....

Closed connection to XSystem
$ 

Here is the contents of the export file (sample) which was created.

Content-Type: Multipart/Related;boundary="___EMC_XOP_BOUNDARY_START___1245537694___EMC_XOP_BOUNDARY_END___";
type="application/xop+xml";
start="<canonicalxset.xml@snia.org>";
start-info="text/xml"
Content-Description: EMC XSet Export Package

--___EMC_XOP_BOUNDARY_START___1245537694___EMC_XOP_BOUNDARY_END___
Content-Type: application/xop+xml; charset=UTF-8; type="text/xml"
Content-Transfer-Encoding: 8bit
Content-ID: <canonicalxset.xml@snia.org>

<xsets xmlns="http://www.snia.org/2007/xam/export"
xmlns:xop="http://www.w3.org/2004/08/xop/include"
xmlns:emcannotations="http://www.emc.com/2008/01/centera/emcannotations"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://www.snia.org/2007/xam/export XAMCanonicalXSetDefinition.xsd
http://www.w3.org/2004/08/xop/include http://www.w3.org/2004/08/xop/include
http://www.emc.com/2008/01/centera/emcannotations emcannotations.xsd ">
<version>1.0.0</version>

<policies>
  <policy name=".xsystem.management.policy.list.default" type="application/vnd.snia.xam.string" readOnly="true" binding="false" length="7" >
    <value>default</value>
  </policy>
</policies>

<xset>
<properties>
    <property name="app.filename" type="application/vnd.snia.xam.string" readOnly="false" binding="true" length="11"  emcannotations:seqno="0"  >
      <value>HelloWorld.</value>
    </property>
    <property name=".xset.time.creation" type="application/vnd.snia.xam.datetime" readOnly="true" binding="true" length="24"  emcannotations:seqno="3"  >
      <value>2009-06-20T22:20:19.000Z</value>
    </property>
    <property name=".xset.time.access" type="application/vnd.snia.xam.datetime" readOnly="true" binding="false" length="24"  emcannotations:seqno="4"  >
      <value>2009-06-20T22:20:21.000Z</value>
    </property>
    <property name=".xset.time.commit" type="application/vnd.snia.xam.datetime" readOnly="true" binding="false" length="24"  emcannotations:seqno="5"  >
      <value>2009-06-20T22:20:21.000Z</value>
    </property>
    <property name=".xset.time.residency" type="application/vnd.snia.xam.datetime" readOnly="true" binding="false" length="24"  emcannotations:seqno="6"  >
      <value>2009-06-20T22:20:21.000Z</value>
    </property>
    <property name=".xset.xuid" type="application/vnd.snia.xam.xuid" readOnly="true" binding="false" length="61"  emcannotations:seqno="7"  >
      <value>AAAEcwA9S8c0UTVHVDdRSDRSUU9VZUVWMkEyTTJGUUw2UUlHNDE0N1ZTMzFKTzFURkxWUjVKNkFDVEo2Ng==</value>
    </property>
    <property name=".xset.time.xuid" type="application/vnd.snia.xam.datetime" readOnly="true" binding="true" length="24"  emcannotations:seqno="8"  >
      <value>2009-06-20T22:20:21.000Z</value>
    </property>
    <property name=".xset.retention.list.base" type="application/vnd.snia.xam.string" readOnly="true" binding="true" length="4"  emcannotations:seqno="9"  >
      <value>base</value>
    </property>
    <property name=".xset.retention.base.enabled" type="application/vnd.snia.xam.boolean" readOnly="true" binding="true" length="1"  emcannotations:seqno="10"  >
      <value>true</value>
    </property>
    <property name=".xset.retention.base.duration" type="application/vnd.snia.xam.int" readOnly="true" binding="true" length="8"  emcannotations:seqno="11"  >
      <value>0</value>
    </property>
    <property name=".xset.retention.base.starttime" type="application/vnd.snia.xam.datetime" readOnly="true" binding="true" length="24"  emcannotations:seqno="12"  >
      <value>2009-06-20T22:20:19.000Z</value>
    </property>
    <property name=".xset.hold" type="application/vnd.snia.xam.boolean" readOnly="true" binding="false" length="1"  emcannotations:seqno="13"  >
      <value>false</value>
    </property>
    <property name=".xset.management.policy" type="application/vnd.snia.xam.string" readOnly="true" binding="false" length="7"  emcannotations:seqno="14"  >
      <value>default</value>
    </property>
    <property name=".vnd.com.emc.centera.meta.standard.binding.creation.poolid" type="application/vnd.snia.xam.string" readOnly="true" binding="true" length="39"  emcannotations:seqno="15"  >
      <value>34372862-1dd2-11b2-aea0-f013836b5e75-10</value>
    </property>
    <property name=".vnd.com.emc.centera.meta.standard.binding.retention.base.enabled" type="application/vnd.snia.xam.string" readOnly="true" binding="true" length="4"  emcannotations:seqno="16"  >
      <value>true</value>
    </property>
    <property name=".vnd.com.emc.centera.meta.standard.binding.sdk.version" type="application/vnd.snia.xam.string" readOnly="true" binding="true" length="7"  emcannotations:seqno="17"  >
      <value>4.0.672</value>
    </property>
    <property name=".vnd.com.emc.centera.meta.standard.binding.modification.poolid" type="application/vnd.snia.xam.string" readOnly="true" binding="true" length="39"  emcannotations:seqno="18"  >
      <value>34372862-1dd2-11b2-aea0-f013836b5e75-10</value>
    </property>
    <property name=".vnd.com.emc.centera.meta.standard.binding.retention.period" type="application/vnd.snia.xam.string" readOnly="true" binding="true" length="1"  emcannotations:seqno="19"  >
      <value>0</value>
    </property>
    <property name=".vnd.com.emc.centera.meta.standard.binding.type" type="application/vnd.snia.xam.string" readOnly="true" binding="true" length="11"  emcannotations:seqno="20"  >
      <value>xam.binding</value>
    </property>
    <property name=".vnd.com.emc.centera.meta.standard.binding.name" type="application/vnd.snia.xam.string" readOnly="true" binding="true" length="29"  emcannotations:seqno="21"  >
      <value>EMC Centera Binding XSet Clip</value>
    </property>
    <property name=".vnd.com.emc.centera.meta.standard.binding.creation.date" type="application/vnd.snia.xam.string" readOnly="true" binding="true" length="23"  emcannotations:seqno="22"  >
      <value>2009.06.20 22:20:19 GMT</value>
    </property>
    <property name=".vnd.com.emc.centera.meta.standard.binding.modification.date" type="application/vnd.snia.xam.string" readOnly="true" binding="true" length="23"  emcannotations:seqno="23"  >
      <value>2009.06.20 22:20:21 GMT</value>
    </property>
    <property name=".vnd.com.emc.centera.meta.standard.binding.creation.profile" type="application/vnd.snia.xam.string" readOnly="true" binding="true" length="13"  emcannotations:seqno="24"  >
      <value>xam_challenge</value>
    </property>
    <property name=".vnd.com.emc.centera.meta.standard.binding.modification.profile" type="application/vnd.snia.xam.string" readOnly="true" binding="true" length="13"  emcannotations:seqno="25"  >
      <value>xam_challenge</value>
    </property>
    <property name=".vnd.com.emc.centera.meta.standard.binding.numfiles" type="application/vnd.snia.xam.string" readOnly="true" binding="true" length="1"  emcannotations:seqno="26"  >
      <value>2</value>
    </property>
    <property name=".vnd.com.emc.centera.meta.standard.binding.totalsize" type="application/vnd.snia.xam.string" readOnly="true" binding="true" length="3"  emcannotations:seqno="27"  >
      <value>731</value>
    </property>
    <property name=".vnd.com.emc.centera.meta.standard.binding.refid" type="application/vnd.snia.xam.string" readOnly="true" binding="true" length="26"  emcannotations:seqno="28"  >
      <value>6T90EGBR9LE5TFLVR5J6ACTJ66</value>
    </property>
    <property name=".vnd.com.emc.centera.meta.standard.binding.clusterid" type="application/vnd.snia.xam.string" readOnly="true" binding="true" length="36"  emcannotations:seqno="29"  >
      <value>34372862-1dd2-11b2-aea0-f013836b5e75</value>
    </property>
    <property name=".vnd.com.emc.centera.meta.standard.binding.prev.clip" type="application/vnd.snia.xam.string" readOnly="true" binding="true" length="0"  emcannotations:seqno="30"  >
      <value></value>
    </property>
    <property name=".vnd.com.emc.centera.meta.standard.binding.clip.naming.scheme" type="application/vnd.snia.xam.string" readOnly="true" binding="true" length="3"  emcannotations:seqno="31"  >
      <value>MD5</value>
    </property>
    <property name=".vnd.com.emc.centera.meta.standard.binding.numtags" type="application/vnd.snia.xam.string" readOnly="true" binding="true" length="1"  emcannotations:seqno="32"  >
      <value>3</value>
    </property>
    <property name=".vnd.com.emc.centera.hidden.nonbinding.clipid" type="application/vnd.snia.xam.string" readOnly="true" binding="false" length="4"  emcannotations:seqno="33"  >
      <value>NULL</value>
    </property>
    <property name=".vnd.com.emc.centera.hidden.binding.clipid" type="application/vnd.snia.xam.string" readOnly="true" binding="true" length="53"  emcannotations:seqno="34"  >
      <value>4Q5GT7QH4RQOUeEV2A2M2FQL6QIG4147VS31JO1TFLVR5J6ACTJ66</value>
    </property>
</properties>
<xstreams>
  <xstream name="com.rhc.file.source" type="application/octet-stream" readOnly="false" binding="true" length="156"  emcannotations:seqno="1"  >
    <xop:Include href='cid:com.rhc.file.source' />
    <emcannotations:emcannotation emcannotations:embedded="false" >
      <emcannotations:emcblobannotation emcannotations:blobguid="1OROBIQ8CLBN3x8HRFRPNS7UV61G4147VS30JN0TFLVR5J6ACTJ66" emcannotations:offset="0" emcannotations:length="156" />
    </emcannotations:emcannotation>
  </xstream>
  <xstream name="com.rhc.file.binary" type="application/base64" readOnly="false" binding="true" length="575"  emcannotations:seqno="2"  >
    <xop:Include href='cid:com.rhc.file.binary' />
    <emcannotations:emcannotation emcannotations:embedded="false" >
      <emcannotations:emcblobannotation emcannotations:blobguid="09D943LSJ49S2xFF94NIQ5B10MGG4147VS31HG0TFLVR5J6ACTJ66" emcannotations:offset="0" emcannotations:length="575" />
    </emcannotations:emcannotation>
  </xstream>
</xstreams>
</xset>
</xsets>

--___EMC_XOP_BOUNDARY_START___1245537694___EMC_XOP_BOUNDARY_END___
Content-Type: text/text
Content-Transfer-Encoding: text
Content-ID: <TOC>

Offset of AAAEcwA9S8c0UTVHVDdRSDRSUU9VZUVWMkEyTTJGUUw2UUlHNDE0N1ZTMzFKTzFURkxWUjVKNkFDVEo2Ng==:com.rhc.file.source: 10955                                                                                                                                                                                                                                                  
Offset of AAAEcwA9S8c0UTVHVDdRSDRSUU9VZUVWMkEyTTJGUUw2UUlHNDE0N1ZTMzFKTzFURkxWUjVKNkFDVEo2Ng==:com.rhc.file.binary: 11285                                                                                                                                                                                                                                                  

--___EMC_XOP_BOUNDARY_START___1245537694___EMC_XOP_BOUNDARY_END___
Content-Type: application/octet-stream
Content-Transfer-Encoding: binary
Content-ID: com.rhc.file.source

/*
 * HelloWorld.java
 *
 */

public class HelloWorld {
    public static void main(String[] args){
       System.out.println("Hello World!");
   }
}

--___EMC_XOP_BOUNDARY_START___1245537694___EMC_XOP_BOUNDARY_END___
Content-Type: application/base64
Content-Transfer-Encoding: binary
Content-ID: com.rhc.file.binary

yv66vgAAADIAHQoABgAPCQAQABEIABIKABMAFAcAFQcAFgEABjxpbml0PgEAAygpVgEABENvZGUB
AA9MaW5lTnVtYmVyVGFibGUBAARtYWluAQAWKFtMamF2YS9sYW5nL1N0cmluZzspVgEAClNvdXJj
ZUZpbGUBAA9IZWxsb1dvcmxkLmphdmEMAAcACAcAFwwAGAAZAQAMSGVsbG8gV29ybGQhBwAaDAAb
ABwBAApIZWxsb1dvcmxkAQAQamF2YS9sYW5nL09iamVjdAEAEGphdmEvbGFuZy9TeXN0ZW0BAANv
dXQBABVMamF2YS9pby9QcmludFN0cmVhbTsBABNqYXZhL2lvL1ByaW50U3RyZWFtAQAHcHJpbnRs
bgEAFShMamF2YS9sYW5nL1N0cmluZzspVgAhAAUABgAAAAAAAgABAAcACAABAAkAAAAdAAEAAQAA
AAUqtwABsQAAAAEACgAAAAYAAQAAAAYACQALAAwAAQAJAAAAJQACAAEAAAAJsgACEgO2AASxAAAA
AQAKAAAACgACAAAACAAIAAkAAQANAAAAAgAO
--___EMC_XOP_BOUNDARY_START___1245537694___EMC_XOP_BOUNDARY_END___--

As you can see this export package is fairly large even though I am only storing two small XStreams in the XSet which I created.

The XSet manifest is everything between the <xsets> and </xsets> tags.  It appears to be a valid and well formed XML document although I have not formally checked it.

The first section, i.e. the <policies> section, lists the XSystem policies that are in effect for the included XSet(s).  Here the policy is set to the default policy for the Xsystem from which I exported the Xset.

It is followed by a section whose top element is <xset> which details the properties and XStream(s) for a single XSet.  Each XSet property element contains the following attributes: type, readonly, binding and length.  Each XStream is mapped to an <xstream> element which contains a child element <xop:include> which contains the content-id to the corresponding MIME part containing the actual contents of the XStream.

As you can see the actual contents of an XStream is included as a MIME attachment after the XSet manifest.  As an aside, note that there is no requirement for an XStream to verify that its contents actually match the declared MIME type. 

The first MIME attachment shown above (AKA the root MIME) lists the offsets of each of the two XStreams.  If an XSet does not contain an XStream, then there are no MIME attachments.  Other than the root MIME attachment the order of the MIME attachments is not significant.  The MIME attachments conform to the requirements of the MIME Multipart/Related Content-type specification (RFC 2387).

Here is the export package generated when StoreHelloWolld was targeted at the SNIA XAM reference VIM (Vendor Interface Module).

Content-Type: Multipart/Related;boundary="--SNIA_REFERENCE_VIM_MIME_BOUNDARY_2009-06-22T21:13:44.330-05:00.XZY_+";type="application/xop+xml";start="<canonicalxset.xml@snia.org>";start-info="text/xml"
Content-Description:Export of XSet: AAA6AwAePKwxMjQ1NzIzMjI0Mjc4ATTLJDRoe2iJ

----SNIA_REFERENCE_VIM_MIME_BOUNDARY_2009-06-22T21:13:44.330-05:00.XZY_+

Content-Type:application/xop+xml;    charset="UTF-8";    type="text/xml"
Content-Transfer-Encoding:8bit
Content-ID:<canonicalxset.xml@snia.org>

<?xml version="1.0" encoding="UTF-8"?>
<xsets xsi:schemaLocation="http://www.snia.org/2007/xam/export/XAMCanonicalXSetDefinition.xsd" xmlns="http://www.snia.org/2007/xam/export" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xop="http://www.w3.org/2004/08/xop/include">
<version>1.0.0</version>
<xset>
<properties>
<property name=".xset.hold" type="application/vnd.snia.xam.boolean" binding="false" readOnly="true" length="1">
        <boolean>false</boolean>
</property>
<property name=".xset.management.policy" type="application/vnd.snia.xam.string" binding="true" readOnly="true" length="36">
        <string>.org.snia.refvim.default.mgmt.policy</string>
</property>
<property name=".xset.retention.base.enabled" type="application/vnd.snia.xam.boolean" binding="true" readOnly="true" length="1">
        <boolean>true</boolean>
</property>
<property name=".xset.retention.base.starttime" type="application/vnd.snia.xam.datetime" binding="true" readOnly="true" length="29">
        <string>2009-06-22T21:13:44.276-05:00</string>
</property>
<property name=".xset.retention.list.base" type="application/vnd.snia.xam.string" binding="true" readOnly="true" length="4">
        <string>base</string>
</property>
<property name=".xset.retention.list.event" type="application/vnd.snia.xam.string" binding="true" readOnly="true" length="5">
        <string>event</string>
</property>
<property name=".xset.time.access" type="application/vnd.snia.xam.datetime" binding="false" readOnly="true" length="29">
        <string>2009-06-22T21:13:44.276-05:00</string>
</property>
<property name=".xset.time.commit" type="application/vnd.snia.xam.datetime" binding="false" readOnly="true" length="29">
        <string>2009-06-22T21:13:44.276-05:00</string>
</property>
<property name=".xset.time.creation" type="application/vnd.snia.xam.datetime" binding="true" readOnly="true" length="29">
        <string>2009-06-22T21:13:44.225-05:00</string>
</property>
<property name=".xset.time.xuid" type="application/vnd.snia.xam.datetime" binding="false" readOnly="true" length="29">
        <string>2009-06-22T21:13:44.276-05:00</string>
</property>
<property name=".xset.xuid" type="application/vnd.snia.xam.xuid" binding="true" readOnly="true" length="30">
        <xuid>AAA6AwAePKwxMjQ1NzIzMjI0Mjc4ATTLJDRoe2iJ</xuid>
</property>
<property name="app.filename" type="application/vnd.snia.xam.string" binding="true" readOnly="false" length="11">
        <string>HelloWorld.</string>
</property>
</properties>
<xstreams>
<xstream name="com.rhc.file.binary" type="application/base64" binding="true" readOnly="false" length="575">
        <org.snia.refvim.xstream_data>XStream_8508062132085140723.data</org.snia.refvim.xstream_data>
<xop:Include href="cid:com.rhc.file.binary@snia.org" xmlns:xop="http://www.w3.org/2004/08/xop/include"/>
</xstream>
<xstream name="com.rhc.file.source" type="application/octet-stream" binding="true" readOnly="false" length="156">
        <org.snia.refvim.xstream_data>XStream_3869980320333904649.data</org.snia.refvim.xstream_data>
<xop:Include href="cid:com.rhc.file.source@snia.org" xmlns:xop="http://www.w3.org/2004/08/xop/include"/>
</xstream>
</xstreams>
</xset>
</xsets>
----SNIA_REFERENCE_VIM_MIME_BOUNDARY_2009-06-22T21:13:44.330-05:00.XZY_+

Content-Type:text/text
Content-Transfer-Encoding:text
Content-ID:<TOC>
Offset of AAA6AwAePKwxMjQ1NzIzMjI0Mjc4ATTLJDRoe2iJ:com.rhc.file.binary@snia.org:3948
Offset of AAA6AwAePKwxMjQ1NzIzMjI0Mjc4ATTLJDRoe2iJ:com.rhc.file.source@snia.org:4706

----SNIA_REFERENCE_VIM_MIME_BOUNDARY_2009-06-22T21:13:44.330-05:00.XZY_+

Content-Type:application/base64
Content-Transfer-Encoding:binary
Content-ID:<com.rhc.file.binary@snia.org>

yv66vgAAADIAHQoABgAPCQAQABEIABIKABMAFAcAFQcAFgEABjxpbml0PgEAAygpVgEABENvZGUB
AA9MaW5lTnVtYmVyVGFibGUBAARtYWluAQAWKFtMamF2YS9sYW5nL1N0cmluZzspVgEAClNvdXJj
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dXQBABVMamF2YS9pby9QcmludFN0cmVhbTsBABNqYXZhL2lvL1ByaW50U3RyZWFtAQAHcHJpbnRs
bgEAFShMamF2YS9sYW5nL1N0cmluZzspVgAhAAUABgAAAAAAAgABAAcACAABAAkAAAAdAAEAAQAA
AAUqtwABsQAAAAEACgAAAAYAAQAAAAYACQALAAwAAQAJAAAAJQACAAEAAAAJsgACEgO2AASxAAAA
AQAKAAAACgACAAAACAAIAAkAAQANAAAAAgAO

----SNIA_REFERENCE_VIM_MIME_BOUNDARY_2009-06-22T21:13:44.330-05:00.XZY_+

Content-Type:application/octet-stream
Content-Transfer-Encoding:binary
Content-ID:<com.rhc.file.source@snia.org>

/*
 * HelloWorld.java
 *
 */

public class HelloWorld {
    public static void main(String[] args){
       System.out.println("Hello World!");
   }
}

----SNIA_REFERENCE_VIM_MIME_BOUNDARY_2009-06-22T21:13:44.330-05:00.XZY_+--

As you can see this export package is considerably more compact then the previous export package generated when I used the EMC Centera XAM VIM.

Well, that is about all for now.  Hopefully this post was useful to you if you are just coming up to speed on XAM and wondering how to import and export XSets.

BTW, Happy Father's Day to all dads who may be reading this post.