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<html xmlns:t="http://tapestry.apache.org/schema/tapestry_5_4.xsd">
<body class="container">
    <h3>Sharing Across Multiple Pages (1)</h3>

    This page demonstrates how to share a bit of data between multiple pages using a Session State Object (an SSO).<br/>
    SSOs are shared between the pages of your web session only, and not with other sessions using the same application.<br/><br/>
    
    To turn a field into an SSO, annotate it with <code>@SessionState</code>.  If any other page or component in your web session 
    declares a field of the same type and annotates it with <code>@SessionState</code> then it will share the same value.<br/><br/>
    
    We use the example of a simple ShoppingBasket object, created in this page and displayed in the next page.

    <div class="eg">
        <t:form class="form-horizontal">
            <div class="form-group">
                <t:label for="applesQuantity" class="col-sm-2"/>
                <div class="col-sm-2">
                    <t:textfield t:id="applesQuantity" value="myBasket.applesQuantity"/>
                </div>
            </div>
            <div class="form-group">
                <t:label for="orangesQuantity" class="col-sm-2"/>
                <div class="col-sm-2">
                    <t:textfield t:id="orangesQuantity" value="myBasket.orangesQuantity"/>
                </div>
            </div>
            <div class="form-group">
                <t:label for="bananasQuantity" class="col-sm-2"/>
                <div class="col-sm-2">
                    <t:textfield t:id="bananasQuantity" value="myBasket.bananasQuantity"/>
                </div>
            </div>
            <div class="form-group">
                <div class="col-sm-4 col-sm-offset-2">
                    <t:submit value="Next &gt;" />
                </div>
            </div>
        </t:form>
    </div>
    
    Tapestry creates this ShoppingBasket object the first time the page uses it.  Other sessions will not see it, 
    but any pages in your session will use it if they declare a field of type ShoppingBasket annotated with 
    @SessionState.<br/><br/>

    <strong>Caution:</strong> A consideration is the impact in clustered servers.  Howard discusses this in 
    <a href="http://thread.gmane.org/gmane.comp.java.tapestry.user/65410/focus=65426">Tapestry App Replication</a> 
    and the documentation discusses it in 
    <a href="http://tapestry.apache.org/persistent-page-data.html#PersistentPageData-ClusteringIssues">Clustering Issues</a>.<br/><br/>
    
    References: 
    <a href="http://tapestry.apache.org/session-storage.html">Session Storage</a>.<br/><br/>
    
    <t:eventlink event="GoHome">Home</t:eventlink><br/><br/>
    
    <t:tabgroup>
        <t:sourcecodetab src="/web/src/main/java/jumpstart/web/pages/examples/state/SharingAcrossMultiplePages1.tml"/>
        <t:sourcecodetab src="/web/src/main/java/jumpstart/web/pages/examples/state/SharingAcrossMultiplePages1.java"/>
        <t:sourcecodetab src="/web/src/main/resources/META-INF/assets/css/examples/plain.css"/>
        <t:sourcecodetab src="/web/src/main/java/jumpstart/web/state/examples/state/ShoppingBasket.java"/>
    </t:tabgroup>
</body>
</html>


package jumpstart.web.pages.examples.state;

import jumpstart.web.pages.Index;
import jumpstart.web.state.examples.state.ShoppingBasket;

import org.apache.tapestry5.annotations.Import;
import org.apache.tapestry5.annotations.Property;
import org.apache.tapestry5.annotations.SessionState;

@Import(stylesheet="css/examples/plain.css")
public class SharingAcrossMultiplePages1 {

    // Screen fields
    
    @SessionState
    @Property
    private ShoppingBasket myBasket;
    
    // The code

    Object onSuccess() {
        return SharingAcrossMultiplePages2.class;
    }

    Object onGoHome() {
        // Delete the SSO from the session
        myBasket = null;
        return Index.class;
    }
}


.eg {
                margin: 20px 0;
                padding: 14px;
                border: 1px solid #ddd;
                border-radius: 6px;
                -webkit-border-radius: 6px;
                -mox-border-radius: 6px;
}


package jumpstart.web.state.examples.state;

public class ShoppingBasket {
    private int applesQuantity;
    private int orangesQuantity;
    private int bananasQuantity;
    
    public int getApplesQuantity() {
        return applesQuantity;
    }

    public void setApplesQuantity(int applesQuantity) {
        this.applesQuantity = applesQuantity;
    }

    public int getOrangesQuantity() {
        return orangesQuantity;
    }

    public void setOrangesQuantity(int orangesQuantity) {
        this.orangesQuantity = orangesQuantity;
    }

    public int getBananasQuantity() {
        return bananasQuantity;
    }

    public void setBananasQuantity(int bananasQuantity) {
        this.bananasQuantity = bananasQuantity;
    }
}