ConversationsList.tml


<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<!-- We need a doctype to allow us to use special characters like &nbsp; 
     We use a "strict" DTD to make IE follow the alignment rules. -->
     
<html xmlns:t="http://tapestry.apache.org/schema/tapestry_5_3.xsd">
<head>
    <link rel="stylesheet" type="text/css" href="${context:css/examples/conversationslist.css}"/>
</head>
<body>
    <h1>Conversations List</h1>
    
    This page shows which "conversations" are in your session.  The Wizard examples use conversations.<br/>
    
    <div class="eg">
        <table class="grid">
            <tr>
                <th>Target</th>
                <th>ConversationId</th>
            </tr>
            <tr t:type="Loop" t:source="allConversations" t:value="conversation">
                <td>${object.class}</td>
                <td><a t:type="eventlink" t:event="GoTo" t:context="conversation.id" href="#">${conversation.id}</a></td>
            </tr>
        </table>
        <div t:type="if" t:test="allConversations" t:negate="true">
            <div class="nodata">(No Conversations to display)</div>
        </div>
    </div>
    
    References: 
    <a href="http://tapestry.apache.org/session-storage.html">Session Storage</a>.<br/><br/>

    <a t:type="pagelink" t:page="Index" href="#">Home</a><br/><br/>

    <t:sourcecodedisplay src="/web/src/main/java/jumpstart/web/pages/examples/wizard/ConversationsList.tml"/>
    <t:sourcecodedisplay src="/web/src/main/java/jumpstart/web/pages/examples/wizard/ConversationsList.java"/>
    <t:sourcecodedisplay src="/web/src/main/java/jumpstart/web/css/examples/conversationslist.css"/>
    <t:sourcecodedisplay src="/web/src/main/java/jumpstart/web/model/Conversation.java"/>
    <t:sourcecodedisplay src="/web/src/main/java/jumpstart/web/model/Conversations.java"/>
</body>
</html>

ConversationsList.java


package jumpstart.web.pages.examples.wizard;

import java.util.Collection;

import jumpstart.web.base.examples.wizard.WizardConversationalPage;
import jumpstart.web.model.Conversation;
import jumpstart.web.model.Conversations;

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

public class ConversationsList {

    // Screen fields

    @Property
    private Collection<Conversation> allConversations;

    @Property
    private Conversation conversation;

    // Other pages

    @InjectPage
    private WizardUsingPages1 creditRequestsWizard;

    // Generally useful bits and pieces

    @SessionState
    private Conversations conversations;

    // The code
    
    void setupRender() {
        allConversations = conversations.getAll();
    }

    Object onGoTo(String conversationId) throws Exception {
        Conversation conversation = conversations.get(conversationId);

        if (conversation != null) {
            // We know of 1 type of conversation only - it belongs to the credit requests wizard
            if (conversation.getObject(WizardConversationalPage.CREDIT_REQUEST_KEY) != null) {
                creditRequestsWizard.set(conversationId);
                return creditRequestsWizard;
            }
        }

        return null;
    }

    public Object getObject() throws Exception {

        if (conversation != null) {
            // We know of 1 type of conversation only - it belongs to the credit requests wizard
            Object object = conversation.getObject(WizardConversationalPage.CREDIT_REQUEST_KEY);
            return object;
        }

        return null;
    }
}

conversationslist.css


body            { font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; font-size: 13px; font-weight: normal; color: #333;
                    line-height: 17px; }
h1              { font-size: 26px; line-height: 20px; } /* For IE 7 */

.eg             { margin: 20px 0; padding: 20px; 
                    border: 1px solid #ddd; border-radius: 4px; -webkit-border-radius: 4px; -mox-border-radius: 4px; }

a               { text-decoration: none; color: #3D69B6; }
a:hover         { text-decoration: underline; }

.grid           { border-collapse: collapse; border-spacing: 0; border: 1px solid #ddd; font-size: 13px; }
.grid tr        { border-top: 1px solid #f8f8f8; }
.grid th        { padding: 3px 5px; text-align: left; width: 400px; border: 1px solid #ddd; 
                    font-weight: normal; background-color: #eee; 
                    filter: progid:DXImageTransform.Microsoft.gradient(startColorstr='#fbfbfb', endColorstr='#e4e4e4'); /* for IE */
                    background: -webkit-gradient(linear, left top, left bottom, from(#fbfbfb), to(#e4e4e4)); /* for webkit browsers */
                    background: -moz-linear-gradient(top, #fbfbfb, #e4e4e4); /* for firefox 3.6+ */ }
.grid td        { padding: 3px 5px; text-align:left; }

.nodata         { margin-top: 5px; margin-left:40px; }

Conversation.java


package jumpstart.web.model;

import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;

public class Conversation {
    private String id;
    private Map<Object, Object> objectsByKey = null;

    public Conversation(String id) {
        this.id = id;
    }

    public String getId() {
        return id;
    }

    public void setObject(Object key, Object obj) {
        if (objectsByKey == null) {
            objectsByKey = new HashMap<Object, Object>(1);
        }
        objectsByKey.put(key, obj);
    }

    public Object getObject(Object key) {
        if (objectsByKey == null) {
            return null;
        }
        else {
            return objectsByKey.get(key);
        }
    }

    public String toString() {
        final String DIVIDER = ", ";

        StringBuilder buf = new StringBuilder();
        buf.append(this.getClass().getSimpleName() + ": ");
        buf.append("[");
        buf.append("id=" + id + DIVIDER);
        buf.append("objectsByKey=");
        if (objectsByKey == null) {
            buf.append("null");
        }
        else {
            buf.append("{");
            for (Iterator<Object> iterator = objectsByKey.keySet().iterator(); iterator.hasNext();) {
                Object key = (Object) iterator.next();
                buf.append("(" + key + "," + "<" + objectsByKey.get(key) == null ? "null" : objectsByKey.get(key).getClass()
                        .getSimpleName()
                        + ">" + ")");
            }
            buf.append("}");
        }
        buf.append("]");
        return buf.toString();
    }
}

Conversations.java


package jumpstart.web.model;

import java.util.Collection;
import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;

public class Conversations {

    private Map<String, Integer> counters = new HashMap<String, Integer>();
    private Map<String, Conversation> conversations = new HashMap<String, Conversation>();

    public String startConversation() {
        return startConversation("dEfAuLt");
    }

    public synchronized String startConversation(String conversationIdPrefix) {
        int conversationNumber = incrementCounter(conversationIdPrefix);
        String conversationId = conversationIdPrefix + Integer.toString(conversationNumber);

        startConversationForId(conversationId);

        return conversationId;
    }

    public synchronized void startConversationForId(String conversationId) {
        Conversation conversation = new Conversation(conversationId);
        add(conversation);
    }

    public void saveToConversation(String conversationId, Object key, Object value) {
        Conversation conversation = get(conversationId);
        // Save a new reference to the object, just in case Tapestry cleans up the other one as we leave the page.
        Object valueNewRef = value;
        conversation.setObject(key, valueNewRef);
    }

    public Object restoreFromConversation(String conversationId, Object key) {
        Conversation conversation = get(conversationId);
        return conversation == null ? null : conversation.getObject(key);
    }

    public void endConversation(String conversationId) {
        remove(conversationId);
    }

    public Collection<Conversation> getAll() {
        return conversations.values();
    }

    public boolean isEmpty() {
        return conversations.isEmpty();
    }

    private synchronized void add(Conversation conversation) {
        if (conversations.containsKey(conversation.getId())) {
            throw new IllegalArgumentException("Conversation already exists. conversationId = " + conversation.getId());
        }
        conversations.put(conversation.getId(), conversation);
    }

    public Conversation get(String conversationId) {
        return conversations.get(conversationId);
    }

    private void remove(String conversationId) {
        Object obj = conversations.remove(conversationId);
        if (obj == null) {
            throw new IllegalArgumentException("Conversation did not exist. conversationId = " + conversationId);
        }
    }

    public synchronized int incrementCounter(String counterKey) {

        if (counters == null) {
            counters = new HashMap<String, Integer>(2);
        }

        Integer counterValue = counters.get(counterKey);

        if (counterValue == null) {
            counterValue = 1;
        }
        else {
            counterValue++;
        }

        counters.put(counterKey, counterValue);
        return counterValue;
    }

    public String toString() {
        final String DIVIDER = ", ";

        StringBuilder buf = new StringBuilder();
        buf.append(this.getClass().getSimpleName() + ": ");
        buf.append("[ ");
        buf.append("counters=");
        if (counters == null) {
            buf.append("null");
        }
        else {
            buf.append("{");
            for (Iterator<String> iterator = counters.keySet().iterator(); iterator.hasNext();) {
                String key = (String) iterator.next();
                buf.append("(" + key + ", " + counters.get(key) + ")");
            }
            buf.append("}");
        }
        buf.append(DIVIDER);
        buf.append("conversations=");
        if (conversations == null) {
            buf.append("null");
        }
        else {
            buf.append("{");
            for (Iterator<String> iterator = conversations.keySet().iterator(); iterator.hasNext();) {
                String key = (String) iterator.next();
                buf.append("(" + key + ", " + conversations.get(key) + ")");
            }
            buf.append("}");
        }
        buf.append("]");
        return buf.toString();
    }

}