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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 JanaBiz.Db;
using JanaBiz.DbXml;
using JanaBiz.DbXml.Exceptions;
public class MutilProcessCmd
{
private static string theContainer = "namespaceExampleData.dbxml";
public static void Main(string[] args)
{
MutilProcessCmd mutilProcessCmd = new MutilProcessCmd();
System.Console.WriteLine("args.Length=" + args.Length);
for(int i = 0;i < args.Length; i++)
{
System.String path = args[i];
System.Console.WriteLine(" args[" + i + "]" + path);
}
string cmd = parseArguments(args);
//string cmd = "2";
System.Console.WriteLine(theContainer);
System.Console.WriteLine("Comand=" + cmd[0] + ";");
switch(cmd[0])
{
case '1':
mutilProcessCmd.doQuery(@"..\..\");
break;
case '2':
mutilProcessCmd.doUpdate(@"..\..\","2");
break;
case '3':
mutilProcessCmd.doUpdate(@"..\..\","3");
break;
default:
System.Console.WriteLine("Unknown command option: " + cmd);
break;
}
}
#region query
// Performs a query against a document using an QueryContext.
private void doContextQuery(XmlManager mgr, string query,
XmlQueryContext context)
{
// Perform a single query against the referenced container using
// the referenced context.
System.Console.WriteLine("Exercising query: '" + query + "'.");
System.Console.WriteLine("Return to continue: ");
//System.Console.ReadLine();
// Perform the query
XmlResults results = mgr.Query(null, query, context, new XmlDocumentConfig());
// Iterate over the results
while(results.MoveNext())
{
//System.Console.WriteLine(results.Current);
using(XmlDocument doc = results.Current.ToDocument())
{
System.Console.WriteLine(" DocumentName=" + doc.Name);
}
}
System.Console.WriteLine(results.Size + " results returned for query '"
+ query + "'.");
}
public void doQuery(string envdir)
{
DbEnvironment dbEnv = null;
XmlManager mgr = null;
XmlContainer container = null;
System.Console.Write("doQuery()");
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");
// Set a variable
context.SetVariableValue("aDessert",
new XmlValue("Blueberry Boy Bait"));
// Perform the queries
// Find all the Vendor documents in the database. Vendor documents do
// not use namespaces, so this query returns documents.
doContextQuery(mgr, "collection(\"" + theContainer +
"\")/vendor", context);
// Find the product document for "Lemon Grass".
// This query returns no documents
// because a namespace prefix is not identified for the 'item' node.
doContextQuery(mgr, "collection(\"" + theContainer +
"\")/item/product[.=\"Lemon Grass\"]", context);
// Find the product document for "Lemon Grass" using the namespace
// prefix 'fruits'. This query successfully returns a document.
doContextQuery(mgr, "collection(\"" + theContainer +
"\")/fruits:item/product[.=\"Lemon Grass\"]", context);
// Find all the vegetables
doContextQuery(mgr, "collection(\"" + theContainer +
"\")/vegetables:item", context);
// Find the dessert called Blueberry Boy Bait.
// Note the use of a variable.
doContextQuery(mgr, "collection(\"" + theContainer +
"\")/desserts:item/product[.=$aDessert]", context);
}
}
}
}
catch(DbXmlException e)
{
System.Console.WriteLine("Error performing query against " + theContainer);
System.Console.WriteLine(e.ToString());
}
finally
{
if(container != null)
{
container.Close();
}
if(mgr != null)
{
mgr.Close();
}
if(dbEnv != null)
{
dbEnv.Close();
}
}
}
#endregion query
#region doUpdate
// Method to add a "description" element after the query's target nodes
private void doModify(XmlManager mgr, XmlContainer container, XmlQueryContext context,
string query, XmlTransaction txn,string updateValue,int updateCount)
{
using(XmlQueryExpression expression = mgr.Prepare(txn, query, context))
{
System.Console.WriteLine("Updating document for the expression: '" +
query + "' ");
System.Console.WriteLine("Return to continue: ");
//System.Console.ReadLine();
// Print the document(s) to be updated -- those that describe
// Zapote Blanco (a fruit). The document strings are only being
// printed to show before/after results.
// Most modification programs would not perform the additional queries.
using(XmlResults results = expression.Execute(txn, context, new XmlDocumentConfig()))
{
//dumpDocuments(results);
results.Reset();
System.Console.WriteLine("About to update the document(s) above.");
System.Console.WriteLine("Look for a new element after the target " +
"element, named 'description' ...");
System.Console.WriteLine("Return to continue: ");
//System.Console.ReadLine();
// The modification is a new element in the target node, called
// "descripton, which goes immediately after the <product> element.
// if this program is run more than once, and committed, additional
// identical elements are added. It is easy to modify this program
// to change the modification.
using(XmlModify modify = mgr.CreateModify())
{
using(XmlQueryExpression subexpr = mgr.Prepare(txn, ".", context))
{
string descriptionValue = "cmd=" + updateValue + ";i=" + updateCount + ";";
modify.AddInsertAfterStep(subexpr, XmlModifyXmlObject.Element, "cmd"+updateValue ,descriptionValue);
using(XmlUpdateContext uc = mgr.CreateUpdateContext())
{
long numMod = modify.Execute(txn, results, context, uc);
System.Console.WriteLine("Performed " + numMod + " modification operations");
dumpDocuments(results);
}
}
}
}
}
}
// display documents matching the query
private void dumpDocuments(XmlResults results)
{
System.Console.WriteLine("Found " + results.Size + " documents ");
results.Reset();
while(results.MoveNext())
{
using(XmlDocument doc = results.Current.ToDocument())
{
System.Console.WriteLine("Document content: ");
System.Console.WriteLine(doc.StringContent);
}
}
}
public void doUpdate(string envdir,string cmd)
{
/**
System.String[] dirs = System.IO.Directory.GetDirectories(envdir);
foreach(System.String path in dirs)
{
System.Console.WriteLine(path);
}
**/
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))
{
for(int updateCount = 0; updateCount < 15; updateCount++)
{
// Start a transaction
using(XmlTransaction txn = mgr.CreateTransaction())
{
// 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");
// Modify the document that describes "Zapote Blanco" (a fruit)
string query = null;
if("2".Equals(cmd))
{
query = "collection(\"" + theContainer + "\")/fruits:item/product[. = 'Zapote Blanco']";
}
else
{
query = "collection(\"" + theContainer + "\")/fruits:item/vendor[. = 'Off the Vine']";
}
doModify(mgr, container, context, query, txn,cmd,updateCount);
txn.Commit();
/**
System.Console.WriteLine("If committed, this program will add a new element each time it is run.");
System.Console.WriteLine("Press 'c' to commit this change:");
int c = System.Console.Read();
if (c == (int)'c' || c == (int)'C')
txn.Commit();
else
txn.Rollback();
**/
}
}
}
}
}
}
catch(DbXmlException e)
{
System.Console.WriteLine("Error performing document modification against " + theContainer);
System.Console.WriteLine(e.ToString());
}
finally
{
if(container != null)
{
container.Close();
}
if(mgr != null)
{
mgr.Close();
}
if(dbEnv != null)
{
dbEnv.Close();
}
}
}
#endregion
#region common config
public 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 = System.Console.Out;
envconf.ErrorPrefix = "PREFIX";
envconf.Private = true;
DbEnvironment env = new DbEnvironment(envdir, envconf);
return env;
}
public XmlManager CreateManager(DbEnvironment env)
{
XmlManagerConfig mgrconfig = new XmlManagerConfig();
mgrconfig.AdoptEnvironment = true;
try
{
return new XmlManager(env, mgrconfig);
}
catch(System.Exception e)
{
env.Close();
throw e;
}
}
#endregion common config
private static string parseArguments(string[] args)
{
string cmd = 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 'c':
{
++i;
if(i >= args.Length)
{
System.Console.WriteLine("Invalid option: " + arg);
Usage();
}
cmd = args[i];
break;
}
default:
{
System.Console.WriteLine("Unknown option: " + arg);
Usage();
break;
}
}
}
else
{
System.Console.WriteLine("Too many arguments: " + arg);
Usage();
}
}
if(cmd == null)
{
System.Console.WriteLine("Environment directory not found.");
Usage();
}
return cmd;
}
private static void Usage()
{
System.Console.WriteLine("This program modifies documents found in a DBXML container.");
System.Console.WriteLine("You should run exampleLoadContainer before running this example.");
System.Console.WriteLine("You are only required to pass this command the path location of the");
System.Console.WriteLine("database environment that you specified when you loaded the examples data:");
System.Console.WriteLine();
System.Console.WriteLine("\t-c <cmd 1,2,3>");
System.Console.WriteLine("For example:");
System.Console.WriteLine("\tmodifyDocument.exe -c 1");
System.Environment.Exit(-1);
}
}
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