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This article answers a common question: “How to read a XML file in a web application?”

I was once in the situation, where I had to find a solution for this problem. So, I would like to share my solution with you.

To demonstrate the solution, I have attached an Eclipse project.  I have used Eclipse Galileo under Windows Vista.

This project is a servlet, which reads a XML file, processes the content and finally prints out the content.

The following steps demonstrates the solution.

1 .The XML – File (excerpt)

<person>
<firstName>Anna</firstName>
<lastName>Sazi</lastName>
</person>

2 . Read in the XML File:

InputStream inputStream = ctx.getResourceAsStream("/WEB-INF/" + XML_FILE_NAME);


Explanation: By this method you obtain an InputStream – Object. It turned out that the file must be located below the WEB-INF folder of the web application. Any other subfolder is also possible.

3. Get a Document – Object

DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
DocumentBuilder db = dbf.newDocumentBuilder();
Document doc = db.parse(inputStream);


Explanation: The aim of these three commands is to get an representation of the XML file which has been read in  during the step 1.

4. Get the values from the node

NodeList firstNameList = element.getElementsByTagName("firstName");
Element firstNameElement = (Element) firstNameList.item(0);
NodeList textFirstNameList = firstNameElement.getChildNodes();
person.setFirstName(((Node) textFirstNameList.item(0)).getNodeValue().trim());


Explanation: This code gets the value of the node whose name is “firstName”. It also adds the obtained value to an “Person” – Object.

5. Print out the values

for(Person person : personList)
{
out.println("<tr>");
out.println("<td>" + person.getFirstName() + "</td>");
out.println("<td>" + person.getLastName() + "</td>");
out.println("</tr>");
}


Explanation: This code prints out the values from the Person list.

For the full code, feel free to download the attached project.

To invoke the servlet, you need to enter “<domain>/XmlReadingExample” into the address bar of your browser.

When using the DB2 JDBC Driver db2jcc on z/OS with type 2 connectivity, running connections to the database will commit its transactions, while the JVM is terminating. This may or may not be the wanted behavior, but this is the default. However, you are able to change this behavior.

To do so you either have to place a file named DB2JccConfiguration.properties in your classpath or you specify a different filename by adding the following VM argument to your java call:

-Ddb2.jcc.propertiesFile=C:/db2jcc.properties

In this file you have to add the following properties:

db2.jcc.promoteAbortToAbend=yes
db2.jcc.rollbackOnShutdown=true


Without the first property a canceled java process will still commit its remaining transactions, because its termination is considered normal. If set to yes or true, the cancel will be promoted to the abend state, which will lead to the action specifed by the second property.
With this property, the db2jcc driver registers a shutdown hook on JVM termination which disables all running connections. After this, no further statements will be accepted by any connection. Right after this the shutdown hook starts to rollback all transactions one by one.