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javaxmlrssmappingsimple-framework

SimpleXML issue

I am working with SimpleXML library. I need to get rss feed and transform it to java object. Here the XML I need to map to the object

<rss xmlns:lj="http://www.livejournal.org/rss/lj/1.0/" xmlns:media="http://search.yahoo.com/mrss/" xmlns:atom10="http://www.w3.org/2005/Atom" version="2.0">
<channel>
<title>Всегда! Везде! Со всеми! и ни с кем!</title>
<link>http://xuma.livejournal.com/</link>
<description>
Всегда! Везде! Со всеми! и ни с кем! - LiveJournal.com
</description>
<lastBuildDate>Thu, 17 Mar 2011 10:08:33 GMT</lastBuildDate>
<generator>LiveJournal / LiveJournal.com</generator>
<lj:journal>xuma</lj:journal>
<lj:journalid>5295048</lj:journalid>
<lj:journaltype>personal</lj:journaltype>
<copyright>NOINDEX</copyright>
<image>
<url>http://l-userpic.livejournal.com/104864030/5295048</url>
<title>Всегда! Везде! Со всеми! и ни с кем!</title>
<link>http://xuma.livejournal.com/</link>
<width>66</width>
<height>100</height>
</image>
<item>
<guid isPermaLink="true">http://xuma.livejournal.com/7831.html</guid>
<pubDate>Thu, 17 Mar 2011 10:08:33 GMT</pubDate>
<title>Япония. Поможем пострадавшим.</title>
<link>http://xuma.livejournal.com/7831.html</link>
<description>...</description>
<comments>http://xuma.livejournal.com/7831.html</comments>
<lj:security>public</lj:security>
<lj:reply-count>0</lj:reply-count>
</item>
<item>
<guid isPermaLink="true">http://xuma.livejournal.com/7575.html</guid>
<pubDate>Sat, 16 Oct 2010 12:36:48 GMT</pubDate>
<link>http://xuma.livejournal.com/7575.html</link>
<description>
<h1>Тест личности</h1><br /><a href="http://teh-nomad.livejournal.com/667478.html"><img border="0" src="http://www.ljplus.ru/img4/a/s/astro_nomad/chtree_6.jpg" alt="" /></a><br /><br /><a href="http://teh-nomad.livejournal.com/667478.html">Выбрать себе дерево</a>
</description>
<comments>http://xuma.livejournal.com/7575.html</comments>
<lj:music>I chase the Devil</lj:music>
<media:title type="plain">I chase the Devil</media:title>
<lj:mood>опаздываю...</lj:mood>
<lj:security>public</lj:security>
<lj:reply-count>0</lj:reply-count>
</item>
</channel>
</rss>

Here are beans I have defined:

@Root
public class RssType {

    @Element(name="channel")
    private ChannelType channel;

    @Attribute
    private String version;

    public ChannelType getChannel() {
        return channel;
    }

    public void setChannel(ChannelType channel) {
        this.channel = channel;
    }

    public String getVersion() {
        return version;
    }

    public void setVersion(String version) {
        this.version = version;
    }


}



@Element(name="channel")
public class ChannelType {

    @Element
    private String title;

    @Element
    private String link;

    @Element
    private String description;

    @Element
    private String lastBuildDate;

    @Element
    private String generator;

    @Element
    @Namespace(reference="http://www.livejournal.org/rss/lj/1.0/", prefix="lj")
    private String journal;

    @Element
    @Namespace(reference="http://www.livejournal.org/rss/lj/1.0/", prefix="lj")
    private String journalid;

    @Element
    @Namespace(reference="http://www.livejournal.org/rss/lj/1.0/", prefix="lj")
    private String journaltype;

    @Element
    private ImageType image;

    @ElementList(inline=false)
    private List<ItemType> item;

    public String getTitle() {
        return title;
    }

    public void setTitle(String title) {
        this.title = title;
    }

    public String getLink() {
        return link;
    }

    public void setLink(String link) {
        this.link = link;
    }

    public String getDescription() {
        return description;
    }

    public void setDescription(String description) {
        this.description = description;
    }

    public String getLastBuildDate() {
        return lastBuildDate;
    }

    public void setLastBuildDate(String lastBuildDate) {
        this.lastBuildDate = lastBuildDate;
    }

    public String getGenerator() {
        return generator;
    }

    public void setGenerator(String generator) {
        this.generator = generator;
    }

    public String getJournal() {
        return journal;
    }

    public void setJournal(String journal) {
        this.journal = journal;
    }

    public String getJournalid() {
        return journalid;
    }

    public void setJournalid(String journalid) {
        this.journalid = journalid;
    }

    public String getJournaltype() {
        return journaltype;
    }

    public void setJournaltype(String journaltype) {
        this.journaltype = journaltype;
    }

    public ImageType getImage() {
        return image;
    }

    public void setImage(ImageType image) {
        this.image = image;
    }

    public List<ItemType> getItem() {
        return item;
    }

    public void setItem(List<ItemType> item) {
        this.item = item;
    }


}


@Element(name="image")
public class ImageType {

    @Element
    private String url;

    @Element
    private String title;

    @Element
    private String link;

    @Element
    private String width;

    @Element
    private String height;


    public String getUrl() {
        return url;
    }

    public void setUrl(String url) {
        this.url = url;
    }

    public String getTitle() {
        return title;
    }

    public void setTitle(String title) {
        this.title = title;
    }

    public String getLink() {
        return link;
    }

    public void setLink(String link) {
        this.link = link;
    }

    public String getWidth() {
        return width;
    }

    public void setWidth(String width) {
        this.width = width;
    }

    public String getHeight() {
        return height;
    }

    public void setHeight(String height) {
        this.height = height;
    }


}


@Element(name="item")
public class ItemType {

    @Element
    private GuidType guid;

    @Element
    private String pubDate;

    @Element
    private String title;

    @Element
    private String link;

    @Element
    private String description;

    @Element
    private String comments;

    @ElementList(inline=false)
    private List<String> category;

    @Element
    @Namespace(reference="http://www.livejournal.org/rss/lj/1.0/", prefix="lj")
    private String security;

    @Element
    @Namespace(reference="http://www.livejournal.org/rss/lj/1.0/", prefix="lj")
    private String replyCount;

    public GuidType getGuid() {
        return guid;
    }

    public void setGuid(GuidType guid) {
        this.guid = guid;
    }

    public String getPubDate() {
        return pubDate;
    }

    public void setPubDate(String pubDate) {
        this.pubDate = pubDate;
    }

    public String getTitle() {
        return title;
    }

    public void setTitle(String title) {
        this.title = title;
    }

    public String getLink() {
        return link;
    }

    public void setLink(String link) {
        this.link = link;
    }

    public String getDescription() {
        return description;
    }

    public void setDescription(String description) {
        this.description = description;
    }

    public String getComments() {
        return comments;
    }

    public void setComments(String comments) {
        this.comments = comments;
    }


    public List<String> getCategory() {
        return category;
    }

    public void setCategory(List<String> category) {
        this.category = category;
    }

    public String getSecurity() {
        return security;
    }

    public void setSecurity(String security) {
        this.security = security;
    }

    public String getReplyCount() {
        return replyCount;
    }

    public void setReplyCount(String replyCount) {
        this.replyCount = replyCount;
    }


}



@Element(name="guid")
public class GuidType {

    @Attribute
    public String isPermaLink;    

    public String text;   

    @Text
    public String getText() {
        return text;
    }

    @Text
    public void setText(String text) {
        this.text = text;
    }

    public String getIsPermaLink() {
        return isPermaLink;
    }

    public void setIsPermaLink(String isPermaLink) {
        this.isPermaLink = isPermaLink;
    }


}

Executing this code :

 String xmlData = retrieve("http://zuma.livejournal.com/data/rss");

        Serializer serializer = new Persister();            

        RssType example = serializer.read(RssType.class, xmlData);

Getting such exception 

org.simpleframework.xml.core.AttributeException: Attribute 'isPermaLink' does not have a match in class com.ljclient.xml.beans.ItemType at line 22

But isPermaLink is not an attribute of <item> node but <guid> node.

If I made isPermaLink to be an attribute of <item> and in that case I'm getting following exception:

org.simpleframework.xml.core.ValueRequiredException: Unable to satisfy @org.simpleframework.xml.ElementList(data=false, empty=true, entry=, inline=false, name=, required=true, type=void) on field 'category' private java.util.List com.ljclient.xml.beans.ItemType.category for class com.ljclient.xml.beans.ItemType at line 22

Its strange because the value exist for each category node. Any ideas?

Solution

  • This is not a direct answer to your question, but have you tried creating RssType instance and writing it to XML. The point of this exercise is that then you can see how your markup translates to XML for any obvious issues.

    public static void main(String[] args) {
    RssType rss = new RssType();
    rss.setVersion("1.0");
    ChannelType channel = new ChannelType();
    channel.setTitle("Test title");
    // Set the rest of the variables
    rss.setChannel(channel);

    //do the same for you other types then
    //convert it to xml

    Serializer serializer = new Persister();
    File result = new File("rss.xml");

    serializer.write(rss, result);
}

    I know that this does not immediately solve the problem, but it should lead you to identifying what the problem is.

    Okay I just tried:

    public static void main(String[] args) throws Exception {
    ItemType item = new ItemType();

    GuidType guid = new GuidType();
    guid.setIsPermaLink("true");
    guid.setText("http://zuma.livejournal.com/147000.html");    
    item.setGuid(guid);
    item.setPubDate("Sun, 07 Oct 2012 06:43:24 GMT");
    item.setTitle("tao machine");
    item.setLink("http://zuma.livejournal.com/147000.html");
    item.setDescription(">&lt;div class=&quot;qpp3&quot;&gt;&lt;div class=&quot;qpp4&quot;&gt;&lt;div class=&quot;qrbrdr1&quot;&gt;&lt;div class=&quot;qrbrdr2&quot;&gt;&lt;center&gt;&lt;img src=&quot;http://zuma.vip.warped.com/transparent_8x8.png&quot;&gt;&lt;br&gt;&lt;a title=&quot;http://stonedmotors.blogspot.com/2012/10/tao-machine.html&quot; href=&quot;http://stonedmotors.blogspot.com/2012/10/tao-machine.html&quot;&gt;&lt;img src=&quot;http://zuma.vip.warped.com/stonedmotors2.png&quot; border=&quot;0&quot;&gt;&lt;/a&gt;&lt;br&gt;&lt;img src=&quot;http://zuma.vip.warped.com/transparent_8x8.png&quot;&gt;&lt;/center&gt;&lt;/div&gt;&lt;/div&gt;&lt;img src=&quot;http://zuma.vip.warped.com/transparent_8x8.png&quot;&gt;&lt;br&gt;&lt;div class=&quot;a720&quot;&gt;&lt;div class=&quot;b720&quot;&gt;&lt;span class=&quot;tnr&quot;&gt;midnight&lt;/span&gt;&lt;br /&gt;&lt;i&gt;&quot;dirt-tired, greased &amp; wired, but the job&apos;s done, hey.&quot;&lt;/i&gt;&lt;br /&gt;&lt;br /&gt;the scattered tools upon the table, all in disarray. the wrenches, sockets, screwdrivers, extensions &amp; adaptors, nuts &amp; bolts &amp; washers scrounged from the floor and about all (mostly) gathered in coffee cans... the piles of parts; case halves, studs, con rods &amp; cranks, camshafts &amp; shims, heads, manifolds, oil radiators, fan housings, distributors, coils, voltage regulators, generators &amp; alternators, carbs &amp; pistons, fuel pumps, filters, trannies, CV joints, axles, brake shoes, fuses, spark plugs, batteries, mufflers, belts, pulleys, flywheels... the cans of mineral spirits, carb cleaner, oil &amp; gas; brake fluid... cleaning a set of wheel bearings w/ an air hose sets it spinning at umpteen hundred RPM. buckets of grease. pressure plates &amp; throw-out bearings. clamps &amp; hoses. breaker bars &amp; torgue wrenches. plastigauge. pedal clusters. cables. shifter plates &amp; bushings. tires, wheels, brake drums clanging, struck by a 5 pound sledge hammer. smoke from the ashtray curls up to the rafters. the coffee pot ticks. we laugh like mad children w/ dirt (like black soot) on our faces &amp; elbows &amp; old worn clothing in the midnight garage.&lt;/div&gt;&lt;/div&gt;&lt;img src=&quot;http://zuma.vip.warped.com/transparent_8x8.png&quot;&gt;&lt;div class=&quot;zim&quot;&gt;&lt;div class=&quot;im1&quot;&gt;&lt;div class=&quot;im2&quot;&gt;&lt;a title=&quot;960x640 version&quot; href=&quot;http://zuma.vip.warped.com/stomo8.png&quot;&gt;&lt;img src=&quot;http://zuma.vip.warped.com/stomo8_716x476.png&quot; border=&quot;0&quot;&gt;&lt;/a&gt;&lt;/div&gt;&lt;/div&gt;&lt;/div&gt;&lt;img src=&quot;http://zuma.vip.warped.com/transparent_8x8.png&quot;&gt;&lt;div class=&quot;a720&quot;&gt;&lt;div class=&quot;b720&quot;&gt;the eternal engine that moves us. forward.&lt;br /&gt;&lt;br /&gt;&lt;i&gt;&quot;i could carve one from a rock...&quot;&lt;/i&gt;&lt;br /&gt;&lt;br /&gt;crank it over. snick it in gear. let out the clutch. foot on the gas in Wide Open Throttle.&lt;br /&gt;&lt;br /&gt;stand on it.&lt;br /&gt;&lt;/div&gt;&lt;/div&gt;&lt;/div&gt;&lt;/div&gt;");
    item.setComments("http://zuma.livejournal.com/147000.html");
    item.setSecurity("public");
    item.setReplyCount("8");
    item.setCategory(new ArrayList<String>());

    Serializer serializer = new Persister();
    File result = new File("rss.xml");

    serializer.write(item, result);
}

    And got:

    <itemType>
   <guid isPermaLink="true">http://zuma.livejournal.com/147000.html</guid>
   <pubDate>Sun, 07 Oct 2012 06:43:24 GMT</pubDate>
   <title>tao machine</title>
   <link>http://zuma.livejournal.com/147000.html</link>
   <description>&gt;&amp;lt;div class=&amp;quot;qpp3&amp;quot;&amp;gt;&amp;lt;div class=&amp;quot;qpp4&amp;quot;&amp;gt;&amp;lt;div class=&amp;quot;qrbrdr1&amp;quot;&amp;gt;&amp;lt;div class=&amp;quot;qrbrdr2&amp;quot;&amp;gt;&amp;lt;center&amp;gt;&amp;lt;img src=&amp;quot;http://zuma.vip.warped.com/transparent_8x8.png&amp;quot;&amp;gt;&amp;lt;br&amp;gt;&amp;lt;a title=&amp;quot;http://stonedmotors.blogspot.com/2012/10/tao-machine.html&amp;quot; href=&amp;quot;http://stonedmotors.blogspot.com/2012/10/tao-machine.html&amp;quot;&amp;gt;&amp;lt;img src=&amp;quot;http://zuma.vip.warped.com/stonedmotors2.png&amp;quot; border=&amp;quot;0&amp;quot;&amp;gt;&amp;lt;/a&amp;gt;&amp;lt;br&amp;gt;&amp;lt;img src=&amp;quot;http://zuma.vip.warped.com/transparent_8x8.png&amp;quot;&amp;gt;&amp;lt;/center&amp;gt;&amp;lt;/div&amp;gt;&amp;lt;/div&amp;gt;&amp;lt;img src=&amp;quot;http://zuma.vip.warped.com/transparent_8x8.png&amp;quot;&amp;gt;&amp;lt;br&amp;gt;&amp;lt;div class=&amp;quot;a720&amp;quot;&amp;gt;&amp;lt;div class=&amp;quot;b720&amp;quot;&amp;gt;&amp;lt;span class=&amp;quot;tnr&amp;quot;&amp;gt;midnight&amp;lt;/span&amp;gt;&amp;lt;br /&amp;gt;&amp;lt;i&amp;gt;&amp;quot;dirt-tired, greased &amp;amp; wired, but the job&amp;apos;s done, hey.&amp;quot;&amp;lt;/i&amp;gt;&amp;lt;br /&amp;gt;&amp;lt;br /&amp;gt;the scattered tools upon the table, all in disarray. the wrenches, sockets, screwdrivers, extensions &amp;amp; adaptors, nuts &amp;amp; bolts &amp;amp; washers scrounged from the floor and about all (mostly) gathered in coffee cans... the piles of parts; case halves, studs, con rods &amp;amp; cranks, camshafts &amp;amp; shims, heads, manifolds, oil radiators, fan housings, distributors, coils, voltage regulators, generators &amp;amp; alternators, carbs &amp;amp; pistons, fuel pumps, filters, trannies, CV joints, axles, brake shoes, fuses, spark plugs, batteries, mufflers, belts, pulleys, flywheels... the cans of mineral spirits, carb cleaner, oil &amp;amp; gas; brake fluid... cleaning a set of wheel bearings w/ an air hose sets it spinning at umpteen hundred RPM. buckets of grease. pressure plates &amp;amp; throw-out bearings. clamps &amp;amp; hoses. breaker bars &amp;amp; torgue wrenches. plastigauge. pedal clusters. cables. shifter plates &amp;amp; bushings. tires, wheels, brake drums clanging, struck by a 5 pound sledge hammer. smoke from the ashtray curls up to the rafters. the coffee pot ticks. we laugh like mad children w/ dirt (like black soot) on our faces &amp;amp; elbows &amp;amp; old worn clothing in the midnight garage.&amp;lt;/div&amp;gt;&amp;lt;/div&amp;gt;&amp;lt;img src=&amp;quot;http://zuma.vip.warped.com/transparent_8x8.png&amp;quot;&amp;gt;&amp;lt;div class=&amp;quot;zim&amp;quot;&amp;gt;&amp;lt;div class=&amp;quot;im1&amp;quot;&amp;gt;&amp;lt;div class=&amp;quot;im2&amp;quot;&amp;gt;&amp;lt;a title=&amp;quot;960x640 version&amp;quot; href=&amp;quot;http://zuma.vip.warped.com/stomo8.png&amp;quot;&amp;gt;&amp;lt;img src=&amp;quot;http://zuma.vip.warped.com/stomo8_716x476.png&amp;quot; border=&amp;quot;0&amp;quot;&amp;gt;&amp;lt;/a&amp;gt;&amp;lt;/div&amp;gt;&amp;lt;/div&amp;gt;&amp;lt;/div&amp;gt;&amp;lt;img src=&amp;quot;http://zuma.vip.warped.com/transparent_8x8.png&amp;quot;&amp;gt;&amp;lt;div class=&amp;quot;a720&amp;quot;&amp;gt;&amp;lt;div class=&amp;quot;b720&amp;quot;&amp;gt;the eternal engine that moves us. forward.&amp;lt;br /&amp;gt;&amp;lt;br /&amp;gt;&amp;lt;i&amp;gt;&amp;quot;i could carve one from a rock...&amp;quot;&amp;lt;/i&amp;gt;&amp;lt;br /&amp;gt;&amp;lt;br /&amp;gt;crank it over. snick it in gear. let out the clutch. foot on the gas in Wide Open Throttle.&amp;lt;br /&amp;gt;&amp;lt;br /&amp;gt;stand on it.&amp;lt;br /&amp;gt;&amp;lt;/div&amp;gt;&amp;lt;/div&amp;gt;&amp;lt;/div&amp;gt;&amp;lt;/div&amp;gt;</description>
   <comments>http://zuma.livejournal.com/147000.html</comments>
   <category class="java.util.ArrayList"/>
   <lj:security xmlns:lj="http://www.livejournal.org/rss/lj/1.0/">public</lj:security>
   <lj:replyCount xmlns:lj="http://www.livejournal.org/rss/lj/1.0/">8</lj:replyCount>
</itemType>

    I noticed that if a field is not set, I was getting and exception. So I simply set everything. Then I edited the xml to look like:

    <itemType>
   <guid isPermaLink="true">http://zuma.livejournal.com/147000.html</guid>
   <pubDate>Sun, 07 Oct 2012 06:43:24 GMT</pubDate>
   <title>tao machine</title>
   <link>http://zuma.livejournal.com/147000.html</link>
   <description>&gt;&amp;lt;div class=&amp;quot;qpp3&amp;quot;&amp;gt;&amp;lt;div class=&amp;quot;qpp4&amp;quot;&amp;gt;&amp;lt;div class=&amp;quot;qrbrdr1&amp;quot;&amp;gt;&amp;lt;div class=&amp;quot;qrbrdr2&amp;quot;&amp;gt;&amp;lt;center&amp;gt;&amp;lt;img src=&amp;quot;http://zuma.vip.warped.com/transparent_8x8.png&amp;quot;&amp;gt;&amp;lt;br&amp;gt;&amp;lt;a title=&amp;quot;http://stonedmotors.blogspot.com/2012/10/tao-machine.html&amp;quot; href=&amp;quot;http://stonedmotors.blogspot.com/2012/10/tao-machine.html&amp;quot;&amp;gt;&amp;lt;img src=&amp;quot;http://zuma.vip.warped.com/stonedmotors2.png&amp;quot; border=&amp;quot;0&amp;quot;&amp;gt;&amp;lt;/a&amp;gt;&amp;lt;br&amp;gt;&amp;lt;img src=&amp;quot;http://zuma.vip.warped.com/transparent_8x8.png&amp;quot;&amp;gt;&amp;lt;/center&amp;gt;&amp;lt;/div&amp;gt;&amp;lt;/div&amp;gt;&amp;lt;img src=&amp;quot;http://zuma.vip.warped.com/transparent_8x8.png&amp;quot;&amp;gt;&amp;lt;br&amp;gt;&amp;lt;div class=&amp;quot;a720&amp;quot;&amp;gt;&amp;lt;div class=&amp;quot;b720&amp;quot;&amp;gt;&amp;lt;span class=&amp;quot;tnr&amp;quot;&amp;gt;midnight&amp;lt;/span&amp;gt;&amp;lt;br /&amp;gt;&amp;lt;i&amp;gt;&amp;quot;dirt-tired, greased &amp;amp; wired, but the job&amp;apos;s done, hey.&amp;quot;&amp;lt;/i&amp;gt;&amp;lt;br /&amp;gt;&amp;lt;br /&amp;gt;the scattered tools upon the table, all in disarray. the wrenches, sockets, screwdrivers, extensions &amp;amp; adaptors, nuts &amp;amp; bolts &amp;amp; washers scrounged from the floor and about all (mostly) gathered in coffee cans... the piles of parts; case halves, studs, con rods &amp;amp; cranks, camshafts &amp;amp; shims, heads, manifolds, oil radiators, fan housings, distributors, coils, voltage regulators, generators &amp;amp; alternators, carbs &amp;amp; pistons, fuel pumps, filters, trannies, CV joints, axles, brake shoes, fuses, spark plugs, batteries, mufflers, belts, pulleys, flywheels... the cans of mineral spirits, carb cleaner, oil &amp;amp; gas; brake fluid... cleaning a set of wheel bearings w/ an air hose sets it spinning at umpteen hundred RPM. buckets of grease. pressure plates &amp;amp; throw-out bearings. clamps &amp;amp; hoses. breaker bars &amp;amp; torgue wrenches. plastigauge. pedal clusters. cables. shifter plates &amp;amp; bushings. tires, wheels, brake drums clanging, struck by a 5 pound sledge hammer. smoke from the ashtray curls up to the rafters. the coffee pot ticks. we laugh like mad children w/ dirt (like black soot) on our faces &amp;amp; elbows &amp;amp; old worn clothing in the midnight garage.&amp;lt;/div&amp;gt;&amp;lt;/div&amp;gt;&amp;lt;img src=&amp;quot;http://zuma.vip.warped.com/transparent_8x8.png&amp;quot;&amp;gt;&amp;lt;div class=&amp;quot;zim&amp;quot;&amp;gt;&amp;lt;div class=&amp;quot;im1&amp;quot;&amp;gt;&amp;lt;div class=&amp;quot;im2&amp;quot;&amp;gt;&amp;lt;a title=&amp;quot;960x640 version&amp;quot; href=&amp;quot;http://zuma.vip.warped.com/stomo8.png&amp;quot;&amp;gt;&amp;lt;img src=&amp;quot;http://zuma.vip.warped.com/stomo8_716x476.png&amp;quot; border=&amp;quot;0&amp;quot;&amp;gt;&amp;lt;/a&amp;gt;&amp;lt;/div&amp;gt;&amp;lt;/div&amp;gt;&amp;lt;/div&amp;gt;&amp;lt;img src=&amp;quot;http://zuma.vip.warped.com/transparent_8x8.png&amp;quot;&amp;gt;&amp;lt;div class=&amp;quot;a720&amp;quot;&amp;gt;&amp;lt;div class=&amp;quot;b720&amp;quot;&amp;gt;the eternal engine that moves us. forward.&amp;lt;br /&amp;gt;&amp;lt;br /&amp;gt;&amp;lt;i&amp;gt;&amp;quot;i could carve one from a rock...&amp;quot;&amp;lt;/i&amp;gt;&amp;lt;br /&amp;gt;&amp;lt;br /&amp;gt;crank it over. snick it in gear. let out the clutch. foot on the gas in Wide Open Throttle.&amp;lt;br /&amp;gt;&amp;lt;br /&amp;gt;stand on it.&amp;lt;br /&amp;gt;&amp;lt;/div&amp;gt;&amp;lt;/div&amp;gt;&amp;lt;/div&amp;gt;&amp;lt;/div&amp;gt;</description>
   <comments>http://zuma.livejournal.com/147000.html</comments>
   <lj:security xmlns:lj="http://www.livejournal.org/rss/lj/1.0/">public</lj:security>
   <lj:replyCount xmlns:lj="http://www.livejournal.org/rss/lj/1.0/">8</lj:replyCount>
</itemType>

    removing the ChannelType value. When I tried to read it back in doing:

    ItemType read = serializer.read(ItemType.class, new File("rss.xml"));

    I get:

    Exception in thread "main" org.simpleframework.xml.core.ValueRequiredException: Unable to satisfy @org.simpleframework.xml.ElementList(entry=, name=, inline=false, data=false, empty=true, type=void, required=true) on field 'category' private java.util.List ItemType.category for class ItemType at line 1
    at org.simpleframework.xml.core.Composite.validate(Composite.java:644)
    at org.simpleframework.xml.core.Composite.readElements(Composite.java:449)
    at org.simpleframework.xml.core.Composite.access$400(Composite.java:59)
    at org.simpleframework.xml.core.Composite$Builder.read(Composite.java:1383)
    at org.simpleframework.xml.core.Composite.read(Composite.java:201)
    at org.simpleframework.xml.core.Composite.read(Composite.java:148)
    at org.simpleframework.xml.core.Traverser.read(Traverser.java:92)
    at org.simpleframework.xml.core.Persister.read(Persister.java:625)
    at org.simpleframework.xml.core.Persister.read(Persister.java:606)
    at org.simpleframework.xml.core.Persister.read(Persister.java:584)
    at org.simpleframework.xml.core.Persister.read(Persister.java:543)
    at org.simpleframework.xml.core.Persister.read(Persister.java:521)
    at org.simpleframework.xml.core.Persister.read(Persister.java:426)
    at Test.main(Test.java:31)

    So basically it is requiring all the fields to be there. So you need to change the @Element and @ElementList(inline=false) annotations to @Element(required=false) and @ElementList(inline=false, required=false) on any optional fields.