java-xml-tool

This java project illustrates the use of XML APIs provided by Java:

• parse and validate XML documents,
• performe XSL-Transformations
• populate a database using JPA from a XML source.

Requirements

• JDK 1.8
• The java project management tool maven, (I use version 3.5.2): Maven
• software version control: git
• optional, for the CarRental Example: Postgres

Installation

1. Change into the directory where your software project live: eg
   cd ~/Developer
2. download - or better clone - the repository "java-xml-tool"
   git clone https://github.com/geschwaerzler/java-xml-tool.git
3. change directory into "java-xml-tool". This directory has been created by the git clone in the previous step.
   cd java-xml-tool
4. compile and build the java tool "XMLTool"   mvn package
5. Test the build, by calling the tool without arguments:   java -jar target/XMLTool.jar
   you should see the following output.

usage:  
	parse xmlfile  
	validate schemafile xmlfile  
	transform xsltfile inputfile outputfile  
	derby jdbcUrl sqlfile  
	load xmlfile  

Congratulations, you just have successfully built your own, simple XML IDE!

Using XMLTool

Validating XML files against XSDs and DTDs

There are two levels of sytactic validity of XML documents. Well-formed XML document obey the general conventions. All XML docuents must be well-formed in order to be processed by a parser. In addition, you may impose strucural rules to a XML documents by supplying DTDs (document type definitions) or XSDs (XML Schema Language Definintions). In this case, we call the XML document valid against that DTD or XSD.

XMLTool implements the following commands:

• check, if the file xml/addresses.xml is well-formed:
  java -jar target/XMLTool.jar parse xml/addresses.xml
• validate file xml/addresses.xml against the schema definition xml/addressbook.xsd
  java -jar target/XMLTool.jar validate src/main/resources/addressbook.xsd xml/addresses.xml
• or validate file xml/car-rental.xml against the document type definition xml/car-rental.dtd
  java -jar target/XMLTool.jar validate src/main/resources/car-rental.dtd xml/car-rental.xml

Transforming XML files with XSLT

XML stylesheet language transformations (XSLT) allow you to convert a given XML structure into another one. The conversion is specified (or let's say programmed) by a so called stylesheet, which is itself a XML document of type XSLT (file-extension .xsl). You may perform a XSL tarsnformation with XSLTool by issueing:

java -jar target/XMLTool.jar transform xml/addresses2html.xsl xml/addresses.xml xml/addresses.html

where the resulting file xml/addresses.html will be created or overwritten. Or alternatively:

java -jar target/XMLTool.jar transform xml/car-rental2html.xsl xml/car-rental.xml xml/car-rental.html

Load XML Data into Database

Addresses

This exmaple illustrates JPA and JAXB APIs using a very simple address book data structure. First, a JAXB DOM is loaded from a XML file.This DOM then is manipulated by adding another address and finally the DOM is traversed (iterated) and stored to the database.

1. Create derby database "addresses"
   java -jar target/XMLTool.jar derby 'jdbc:derby:derby.data/addresses;create=true' db/createDbAddresses.sql
2. Load XML file "addresses.xml" into database addresses   java -jar target/XMLTool.jar load xml/addresses.xml
3. List the database content:   java -jar target/XMLTool.jar derby 'jdbc:derby:derby.data/addresses' db/listAddresses.sql

Messages2

Have a look at the source code of scr/main/java/at/fhv/xmltool/Addresses.java. See, how the XML dom-tree is traversed and JPA objects are built and persisted. scr/main/java/at/fhv/xmltool/Messages2.java is a skeletton, that needs only one or two dozens of code lines in order to load the messages2 DB! Try it yourself.

1. Create derby database "messages2"   java -jar target/XMLTool.jar derby 'jdbc:derby:derby.data/messages2;create=true' db/createDbMessages2.sql
2. Load XML file "messages2.xml" into database messages2   java -jar target/XMLTool.jar load xml/messages2.xml
3. List the database content:   java -jar target/XMLTool.jar derby 'jdbc:derby:derby.data/messages2;create=true' db/listMessages2.sql

CarRental

This example requires a running PostgreSQL DBMS on your system and access to the postgres command line tools.

1. Create postgres database "CarRental"   psql -f db/createDbCarRental.sql CarRental
2. Load XML file "messages2.xml" into database messages2   java -jar target/XMLTool.jar load xml/car-rental.xml
3. List the database content:   psql -f db/listCarRental.sql CarRental

(Re-)Generate JPA-Classes with Hibernate-Tool Reengineering

• Re-(generate) at.fhv.xmltool.addressbook.jpa.* classes:   mvn antrun:run@addresses2java
• Re-(generate) at.fhv.xmltool.message2.jpa.* classes:   mvn antrun:run@messages2java
• Re-(generate) at.fhv.xmltool.carrental.jpa.* classes:   mvn antrun:run@carRental2java