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/*
* Berkeley DB XML .NET API
*
* Copyright (C) 2007 Jana Business Consulting Ltd. All rights reserved.
*
* For more information, see http://www.janabiz.com.
*
*/
using System;
using JanaBiz.Db;
using JanaBiz.DbXml;
using JanaBiz.DbXml.Exceptions;
public class QueryWithDocumentNames
{
private static string theContainer = "namespaceExampleData.dbxml";
// Performs a query against a document using an XmlQueryContext.
private static void doContextQuery(XmlManager mgr, string query,
XmlQueryContext context)
{
// Perform a single query against the referenced container using
// the referenced context.
Console.WriteLine("Exercising query: '" + query + "'.");
Console.WriteLine("Return to continue: ");
Console.ReadLine();
// Perform the query
XmlResults results = mgr.Query(null, query, context, new XmlDocumentConfig());
// Iterate over the results
while (results.MoveNext()) {
using (XmlDocument document = results.Current.ToDocument()) {
Console.WriteLine("Document name: " + document.Name);
Console.WriteLine(results.Current);
}
}
Console.WriteLine(results.Size + " results returned for query '"
+ query + "'.");
}
public static void Main(string[] args)
{
string envdir = parseArguments(args);
DbEnvironment dbEnv = null;
XmlManager mgr = null;
XmlContainer container = null;
try {
// Open an environment
dbEnv = CreateDbEnvironment(envdir);
// Open a manager
using (mgr = CreateManager(dbEnv)) {
// Open a transactional container
XmlContainerConfig containerconfig = new XmlContainerConfig();
containerconfig.Transactional = true;
using (container = mgr.OpenContainer(null, theContainer,
containerconfig)) {
// Create a context and declare the namespaces
using (XmlQueryContext context = mgr.CreateQueryContext()) {
context.SetNamespace("fruits", "http://groceryItem.dbxml/fruits");
context.SetNamespace("vegetables", "http://groceryItem.dbxml/vegetables");
context.SetNamespace("desserts", "http://groceryItem.dbxml/desserts");
// Query for documents using their document names.
// The name is stored as meta data on the document, using the
// namespace "http://www.sleepycat.com/2002/dbxml" and the name
// "name".
// Notice that you do NOT have to declare the dbxml namespace in
// the QueryContext used for this query. Also, each document name
// was set by exampleLoadContainer when the document was loaded into
// the Container.
doContextQuery(mgr, "collection(\"" + theContainer +
"\")[dbxml:metadata('dbxml:name')='ZuluNut.xml']",
context);
doContextQuery(mgr, "collection(\"" + theContainer +
"\")[dbxml:metadata('dbxml:name')='TrifleOrange.xml']",
context);
doContextQuery(mgr, "collection(\"" + theContainer +
"\")[dbxml:metadata('dbxml:name')='TriCountyProduce.xml']",
context);
doContextQuery(mgr, "collection(\"" + theContainer +
"\")[/fruits:item/product=\"Zulu Nut\"]",
context);
}
}
}
} catch (DbXmlException e) {
Console.WriteLine("Error performing query against " + theContainer);
Console.WriteLine(e.ToString());
} finally {
if (container != null) {
container.Close();
}
if (mgr != null) {
mgr.Close();
}
if (dbEnv != null) {
dbEnv.Close();
}
}
}
public static DbEnvironment CreateDbEnvironment(string envdir)
{
DbEnvironmentConfig envconf = new DbEnvironmentConfig();
envconf.CacheSize = 50*1024;
envconf.AllowCreate = true;
envconf.InitializeCache = true;
envconf.Transactional = true;
envconf.InitializeLocking = true;
envconf.InitializeLogging = true;
envconf.RunRecovery = true;
envconf.ErrorWriter = Console.Out;
envconf.ErrorPrefix = "LOG";
DbEnvironment env = new DbEnvironment(envdir, envconf);
return env;
}
public static XmlManager CreateManager(DbEnvironment env)
{
XmlManagerConfig mgrconfig = new XmlManagerConfig();
mgrconfig.AdoptEnvironment = true;
try {
return new XmlManager(env, mgrconfig);
} catch (Exception e) {
env.Close();
throw e;
}
}
private static void Usage()
{
Console.WriteLine("This program retrieves DB XML documents using their document names.");
Console.WriteLine("You should run exampleLoadContainer before running this example.");
Console.WriteLine("You are only required to pass this command the path location of the database");
Console.WriteLine("environment that you specified when you loaded the examples data:");
Console.WriteLine();
Console.WriteLine("\t-h <dbenv directory>");
Console.WriteLine("For example:");
Console.WriteLine("\tqueryWithDocumentNames.exe -h examplesEnvironment");
Environment.Exit(-1);
}
private static string parseArguments(string[] args)
{
string envdir = null;
for (int i = 0; i < args.Length; ++i) {
string arg = args[i];
if ((arg.StartsWith("-")
#if WIN32
|| arg.StartsWith("/")
#endif
) && arg.Length > 1) {
switch (arg[1]) {
case 'h':
{
++i;
if (i >= args.Length) {
Console.WriteLine("Invalid option: " + arg);
Usage();
}
envdir = args[i];
break;
}
default:
{
Console.WriteLine("Unknown option: " + arg);
Usage();
break;
}
}
} else {
Console.WriteLine("Too many arguments: " + arg);
Usage();
}
}
if (envdir == null) {
Console.WriteLine("Environment directory not found.");
Usage();
}
return envdir;
}
}
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