XML Class Generator for Java, Schema Example 3b: Application: TestPo.java

Examples Using XML Java Class Generator with DTDs and XML Schema



PurchaseOrder.PurchaseOrder_Type.ShipTo shipTo =

new PurchaseOrder.PurchaseOrder_Type.ShipTo();

// Create Address

Address address = new Address();

// Create the Name for the address and add

// it to addresss

Address.Name name = new Address.Name();

name.setType("Mary Smith");

address.addName(name);

// Create the Stree name for the address and add

// it to the address

Address.Street street = new Address.Street();

street.setType("Laurie Meadows");

address.addStreet(street);

// Create the city name for the address and add

// it to the address

Address.City city = new Address.City();

city.setType("San Mateo");

address.addCity(city);

// Create the zip name for the address and add

// it to the address

Address.Zip zip = new Address.Zip();

zip.setType(new Double("11208"));

address.addZip(zip);

// Set the address of the shipTo object

shipTo.setType(address);

// Add the shipTo to the Purchase Type object

poType.addShipTo(shipTo);

// Create a Purchase Order BillTo item

PurchaseOrder.PurchaseOrder_Type.BillTo billTo =

new PurchaseOrder.PurchaseOrder_Type.BillTo();

// Create a billing Address

Address billingAddress = new Address();

// Create the name for billing address, set the

// name and add it to the billing address

Address.Name name1 = new Address.Name();



XML Class Generator for Java 7-27



Examples Using XML Java Class Generator with DTDs and XML Schema



name1.setType("John Smith");

billingAddress.addName(name1);

// Create the street name for the billing address,

// set the street name value and add it to the

// billing address

Address.Street street1 = new Address.Street();

street1.setType("No 1. North Broadway");

billingAddress.addStreet(street1);

// Create the City name for the address, set the

// city name value and add it to the billing address

Address.City city1 = new Address.City();

city1.setType("New York");

billingAddress.addCity(city1);

// Create the Zip for the address, set the zip

// value and add it to the billing address.

Address.Zip zip1 = new Address.Zip();

zip1.setType(new Double("10006"));

billingAddress.addZip(zip1);

// Set the type of the billTo object to billingAddress

billTo.setType(billingAddress);

// Add the billing address to the PurchaseOrder type

poType.addBillTo(billTo);

PurchaseOrder.PurchaseOrder_Type.Items pItem =

new PurchaseOrder.PurchaseOrder_Type.Items();

Items items = new Items();

Items.Item item = new Items.Item();

Items.Item.Item_Type itemType = new Items.Item.Item_Type();

Items.Item.Item_Type.ProductName pname =

new Items.Item.Item_Type.ProductName();

pname.setType("Perfume");

itemType.addProductName(pname);

Items.Item.Item_Type.Quantity qty =

new Items.Item.Item_Type.Quantity();

qty.setType(new Integer("1"));

itemType.addQuantity(qty);



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Frequently Asked Questions About the Class Generator for Java



Items.Item.Item_Type.Price price =

new Items.Item.Item_Type.Price();

price.setType(new Double("69.99"));

itemType.addPrice(price);

Items.Item.Item_Type.ShipDate sdate =

new Items.Item.Item_Type.ShipDate();

sdate.setType("Feb 14. 2000");

itemType.addShipDate(sdate);

itemType.setPartNum("ITMZ411");

item.setType(itemType);

items.addItem(item);

pItem.setType(items);

poType.addItems(pItem);

// Set the type of the Purchase Order object to

// Purchase Order Type

po.setType(poType);

po.print(out);

out.writeNewLine();

out.flush();

}

catch (InvalidContentException e)

{

System.out.println(e.getMessage());

e.printStackTrace();

}

catch (Exception e)

{

System.out.println(e.toString());

e.printStackTrace();

}

}

}



Frequently Asked Questions About the Class Generator for Java

This section lists XML Java Class Generator questions and answers.



XML Class Generator for Java 7-29



Frequently Asked Questions About the Class Generator for Java



How Do I Install the XML Class Generator for Java?

Answer: The Class Generator is packaged as part of the XDK and so you do not

have to download it separately. The CLASSPATH should be set to include

classgen.jar, xmlparserv2.jar, and xschema.jar which are located in the

lib/ directory and not in the bin/ directory.



What Does the XML Class Generator for Java Do?

What does the XML Class Generator for Java do? How do I use it to get XML data?

Answer: The XML Class Generator for Java creates Java source files from an XML

DTD. This is useful when you need an application to send an XML message to

another application based on an agreed-upon DTD or as the back end of a Web form

to construct an XML document. Using these classes, Java applications can construct,

validate, and print XML documents that comply with the input DTD. The Class

Generator works in conjunction with the Oracle XML Parser for Java version 2,

which parses the DTD and passes the parsed document to the class generator.

To get XML data, first, get the data from the database using JDBC ResultSets. Then,

instantiate objects using the classes generated by the XML Class Generator.



Which DTDs Are Supported?

Does XML Java Class Generator support any kind of DTD?

Answer: Yes, it supports any kind of DTD that is XML 1.0 compliant.



Why Do I Get a "Classes Not Found" Error?

Why do I get a "Class Not Found" error when running XML Class Generator

samples?

Answer: Correct your CLASSPATH to include classgen.jar, xmlparserv2.jar,

and xschema.jar.



In XML Class Generator, How Do I Create the Root Object More Than Once?

I generated, from a DTD, a set of Java classes with the Class Generator. Since then,

I’ve tried to create a Java application that uses these classes to create an XML file

from data passed as arguments. I cannot create the root object, the object derived

from CGDocument, more than one time because I obtain the following error

message:



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Frequently Asked Questions About the Class Generator for Java



oracle.xml.parser.XMLDOMException: Node doesn’t belong to the current document



How do I handle the star operator (*)? When the application starts I do not know

how many times the element will appear. Thus I do not build a static loop where I

make a sequence of element.addNode(). The problem is that some of these will

be empty and I will obtain an XML document with a set of empty elements with

empty attributes.

Answer: You can create subsequent XML docs by calling the constructor each time.

A well-formed XML document is not permitted to have more than one root node,

therefore you cannot use the star operator (*) on the element you are designating as

the document root.



How Can I Create XML Files from Scratch Using the DOM API?

I want to create an XML file using the DOM API. I do not want to create the XML

file by typing in the text editor:



is great





Instead, I want to create it using the DOM API. There are several examples of

manipulating an XML file using the DOM once there is an input file, but not the

other way round. That is, of creating the XML file from scratch (when there is no

input file) using the DOM, once you know the tagnames and their values.

Answer: The simplest way is download XML Class Generator for Java and give it a

DTD of the XML document you want. It will create the DOM classes to

programmatically create XML documents. There are samples included with the

software.



Can I Create an XML Document in a Java Class?

I need to create an XML document in a Java class as follows

test

test







XML Class Generator for Java 7-31



Frequently Asked Questions About the Class Generator for Java



Can I use the XMLDocument class to create an XML document? I know about the

XML SQL Utility, but that only creates XML based on SQL queries, which is not

what I am after on this occasion. Do you have an example of how to do this?

Answer: The XML Class Generator, available as part of the Oracle XDK for Java,

does the job nicely. The XDKs are also available with Oracle9i and Oracle9i

Application Server products. The Class Generator generates Java classes for each

element in your DTD. These classes can then be used to dynamically construct an

XML document at runtime. The Class Generator download contains sample code.



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Oracle9i XML Developer’s Kits Guide - XDK



8

XML SQL Utility (XSU)

This chapter contains the following sections:

s



What Is XML SQL Utility (XSU)?



s



XSU Dependencies and Installation



s



XML SQL Utility and the Bigger Picture



s



SQL-to-XML and XML-to-SQL Mapping Primer



s



How XML SQL Utility Works



s



Using the XSU Command Line Front End, OracleXML



s



XSU Java API



s



Generating XML with XSU’s OracleXMLQuery



s



Paginating Results: skipRows and maxRows



s



Generating XML from ResultSet Objects



s



Raising No Rows Exception



s



Storing XML Back in the Database Using XSU OracleXMLSave



s



Insert Processing Using XSU (Java API)



s



Update Processing Using XSU (Java API)



s



Delete Processing Using XSU (Java API)



s



Advanced XSU Usage Techniques



s



Frequently Asked Questions About XML SQL Utility (XSU)



XML SQL Utility (XSU) 8-1



What Is XML SQL Utility (XSU)?



What Is XML SQL Utility (XSU)?

XML has become the format for data interchange. At the same time, a substantial

amount of business data resides in object-relational databases. It is therefore

necessary to have the ability to transform this relational data to XML.

XML SQL Utility (XSU) enables you to do this as follows:

s



s



s



XSU can transform data retrieved from object-relational database tables or

views into XML.

XSU can extract data from an XML document, and using a canonical mapping,

insert the data into appropriate columns or attributes of a table or a view.

XSU can extract data from an XML document and apply this data to updating

or deleting values of the appropriate columns or attributes.



Generating XML from the Database

For example, on the XML generation side, when given the query SELECT * FROM

emp, XSU queries the database and returns the results as the following XML

document:







7369

Smith

CLERK

7902

12/17/1980 0:0:0

800

20









Storing XML in the Database

Going the other way, given the XML document preceding, XSU can extract the data

from it and insert it into the scott.emp table in the database.



Accessing XSU Functionality

XML SQL Utility functionality can be accessed in the following ways:



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Oracle9i XML Developer’s Kits Guide - XDK



What Is XML SQL Utility (XSU)?



s



Through a Java API



s



Through a PL/SQL API



s



Through a Java command line front end

See Also:

s



Oracle9i XML API Reference - XDK and Oracle XML DB



XSU Features

XSU can perform the following tasks:

s



s



s



s



s



s



Generate XML documents from any SQL query. XSU virtually supports all the

datatypes supported in the Oracle9i database server.

Dynamically generate DTDs (Document Type Definitions).

During generation, perform simple transformations, such as modifying default

tag names for the ROW element. You can also register an XSL transformation

which is then applied to the generated XML documents as needed.

Generate XML documents in their string or DOM representations.

Insert XML into database tables or views. XSU can also update or delete records

records from a database object, given an XML document.

Easily generate complex nested XML documents. XSU can also store them in

relational tables by creating object views over the flat tables and querying over

these views. Object views can create structured data from existing relational

data using Oracle8i and Oracle9i’s object-relational infrastructure.



XSU Oracle9i New Features

Starting in Oracle9i, XSU can also perform the following tasks:

s



Generates XML Schema given an SQL Query.



s



Generates XML as a stream of SAX2 callbacks.



s



s



Supports XML attributes during generation. This provides an easy way to

specify that a particular column or group of columns should be mapped to an

XML attribute instead of an XML element.

SQL identifier to XML identifier escaping. Sometimes column names are not

valid XML tag names. To avoid this you can either alias all the column names or

turn on tag escaping.



XML SQL Utility (XSU) 8-3



XSU Dependencies and Installation



Note: Oracle9i introduced the DBMS_XMLGen PL/SQL supplied

package. This package provides the functionality previously

available with DBMS_XMLQuery. DBMS_XMLGen is built into the

database code, hence, it provides better performance.



XSU Supports XMLType

From Oracle9i Release 2 (9.2), XSU supports XMLType. Using XSU with XMLType is

useful if, for example, you have XMLType columns in objects or tables.

See Also: Oracle9i XML Database Developer’s Guide - Oracle XML



DB, in particular, the chapter on Generating XML, for examples on using

XSU with XMLType.



XSU Dependencies and Installation

Dependencies

XML SQL Utility (XSU) needs the following components:

s



s



Database connectivity -- JDBC drivers. XSU can work with any JDBC driver

but is optimized for Oracle JDBC drivers. Oracle does not make any guarantee

or provide support for the XSU running against non-Oracle databases.

XML Parser -- Oracle XML Parser, Version2. Oracle XML Parser, version 2 is

included in Oracle8i and Oracle9i, and is also available as part of the XSU install

(XDK for Java) downloadable from the Oracle Technology Network (OTN) Web

site.



Installation

XML SQL Utility (XSU) is packaged with Oracle8i (8.1.7 and later) and Oracle9i.

XSU is made up of three files:

s



s



8-4



$ORACLE_HOME/rdbms/jlib/xsu12.jar -- Contains all the Java classes

which make up XSU. xsu12 requires JDK1.2.x and JDBC2.x. This is the

XSU version loaded into Oracle9i.

$ORACLE_HOME/rdbms/jlib/xsu111.jar -- Contains the same classes as

xsu12.jar, except that xsu111 requires JDK1.1.x and JDBC1.x.



Oracle9i XML Developer’s Kits Guide - XDK



XML SQL Utility and the Bigger Picture



s



$ORACLE_HOME/rdbms/admin/dbmsxsu.sql -- This is the SQL script that

builds the XSU PL/SQL API. xsu12.jar needs to be loaded into the database

before dbmsxsu.sql is executed.



By default the Oracle9i installer installs XSU on the hard drive in the locations

specified earlier. It also loads it into the database.

If during initial installation you choose to not install XSU, you can install it later, but

the installation becomes less simple. To install XSU later, first install XSU and its

dependent components on your system. You can accomplish this using Oracle

Installer. Next perform the following steps:

1.



If you have not yet loaded XML Parser for Java in the database, go to

$ORACLE_HOME/xdk/lib. Here you will find xmlparserv2.jar that you

need to load into the database. To do this, see “Loading JAVA Classes” in the

Oracle9i Java Stored Procedures Developer’s Guide



2.



Go to $ORACLE_HOME/admin and run catxsu.sql

Note: XML SQL Utility (XSU) is part of the XDK for Java and is



also available on OTN at: http://otn.oracle.com/tech/xml



XML SQL Utility and the Bigger Picture

XML SQL Utility (XSU) is written in Java, and can live in any tier that supports

Java.



XML SQL Utility in the Database

The Java classes which make up XSU can be loaded into Java-enabled Oracle8i or

later. Also, XSU contains a PL/SQL wrapper that publishes the XSU Java API to

PL/SQL, creating a PL/SQL API. This way you can:

s



Write new Java applications that run inside the database and that can directly

access the XSU Java API



s



Write PL/SQL applications that access XSU through its PL/SQL API



s



Access XSU functionality directly through SQL

Note: To load and run Java code inside the database you need a



Java-enabled Oracle8i or later server.



XML SQL Utility (XSU) 8-5