The primary goal of this example is to illustrate how Smooks can be used to transform XML into a Java Object Graph.

The Input Message
The Java Beans (POJOs)
The Smooks Configuration
Executing Smooks

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To Build: "mvn clean install"
To Run: "mvn exec:java"

Additional information relevant to this example:

Check out the "xml-to-java" example.
Check out the javadoc for the Javabean Cartridge (see the BeanPopulator class).

The Input Message

The input message is an order as follows:

<order>
    <header>
        <date>Wed Nov 15 13:45:28 EST 2006</date>
        <customer number="123123">Joe</customer>
    </header>
    <order-items>
        <order-item>
            <product>111</product>
            <quantity>2</quantity>
            <price>8.90</price>
        </order-item>
        <order-item>
            <product>222</product>
            <quantity>7</quantity>
            <price>5.20</price>
        </order-item>
    </order-items>
</order>

The Java Beans (POJOs)

We have 3 basic types - Order, Header and OrderItem.

The Order (getters and setters not shown) contains a Header and a list of OrderItems:

public class Order {
    private Header header;
    private List<OrderItem> orderItems;
}

The Header (getters and setters not shown):

public class Header {
    private Date date;
    private Long customerNumber;
    private String customerName;
}

The OrderItem (getters and setters not shown):

public class OrderItem {
    private long productId;
    private Integer quantity;
    private double price;
}

The Smooks Configuration

The Smooks config required to bind the data from the Input Message into the Order object graph is as follows:

<!-- smooks-config.xml -->
<?xml version="1.0"?>
<smooks-resource-list xmlns="http://www.milyn.org/xsd/smooks-1.1.xsd" xmlns:jb="http://www.milyn.org/xsd/smooks/javabean-1.1.xsd">

    <!--
    Create an "example.beans.Order" bean instance when we visit the start of the <order> element.
    Assign the new bean instance to the beanId of "order".
    Wire in the "header" and "orderItems" beans.
    -->
    <jb:bindings beanId="order" class="example.model.Order" createOnElement="order">
        <jb:wiring property="header" beanIdRef="header" />
        <jb:wiring property="orderItems" beanIdRef="orderItems" />
    </jb:bindings>

    <!--
    Create an ArrayList bean instance when we visit the start of the <order> element.
    This bean is wired into the "order" bean.
    -->
    <jb:bindings beanId="orderItems" class="java.util.ArrayList" createOnElement="order">
        <jb:wiring beanIdRef="orderItem" />
    </jb:bindings>

    <!--
    Create an "example.beans.Header" bean instance when we visit the start of the <header> element.
    This bean is wired into the "order" bean.
    -->
    <jb:bindings beanId="header" class="example.model.Header" createOnElement="header">
        <jb:value property="date" decoder="Date" data="header/date">
            <jb:decodeParam name="format">EEE MMM dd HH:mm:ss z yyyy</jb:decodeParam>
            <jb:decodeParam name="locale-language">en</jb:decodeParam>
            <jb:decodeParam name="locale-country">IE</jb:decodeParam>
        </jb:value>
        <jb:value property="customerNumber" decoder="Long" data="header/customer/@number" />
        <jb:value property="customerName" data="header/customer" />
    </jb:bindings>

    <!--
    Create an "example.beans.OrderItem" bean instance when we visit the start of the <order-item> element.
    This bean is wired into the "orderItems" ArrayList bean.
    -->
    <jb:bindings beanId="orderItem" class="example.model.OrderItem" createOnElement="order-item">
        <jb:value property="productId" decoder="Long" data="order-item/product" />
        <jb:value property="quantity" decoder="Integer" data="order-item/quantity" />
        <jb:value property="price" decoder="Double" data="order-item/price" />
    </jb:bindings>

</smooks-resource-list>

For more info on Javabean decoders, see the DataDecoder Javadocs.

Executing Smooks

As with the java-basic tutorial, we use the Smooks class as follows:

// Instantiate Smooks with the config...
Smooks smooks = new Smooks("smooks-config.xml");
JavaResult javaResult = new JavaResult();

// Filter the input message to the JavaResult...
smooks.filter(new StreamSource(messageIn), javaResult);

// Extract the Order bean from the JavaResult using the beanId...
Order order = (Order) javaResult.getBean("order");

Of course, you'd typically cache the Smooks instance.

See the example/Main.java in the example source.

Smooks Example - xml-to-java

The Input Message

The Java Beans (POJOs)

The Smooks Configuration

Executing Smooks

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madhavan