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POHibernate mapping returns null properties
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  1. POHibernate mapping returns null properties
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    copied!<p>I have a Hibernate mapping setup. The table is species, my Java class is Species. hibernate.cfg.xml points to mappings in species.hbn.xml</p> <p>In my code I'm using a simple HQL query and then throwing the resultant Species instances into a "SpeciesLister" class (which I'm passing over to the presentation layer).</p> <pre><code> SpeciesLister speciesList = new SpeciesLister(); Query q = session.createQuery("SELECT s FROM Species s"); for (Species s : (List&lt;Species&gt;) q.list()){ speciesList.addSpecies(s); } </code></pre> <p>The Species class looks like this:</p> <pre><code>package springwildlife; public class Species implements Serializable { long id; String commonName; String latinName; String order; String family; ArrayList&lt;Sighting&gt; sightings; public Species() { } public Species(String commonName, String latinName) { sightings = new ArrayList&lt;Sighting&gt;(); this.commonName = commonName; this.latinName = latinName; } public long getId() { return id; } public String getCommonName() { return commonName; } public String getLatinName() { return latinName; } public String getOrder() { return order; } public String getFamily() { return family; } public ArrayList&lt;Sighting&gt; getSightings() { return sightings; } public void addSighting(Sighting s) { sightings.add(s); } public void setId(long id) { this.id = id; } public void setCommonName(String cn) { commonName = cn; } public void setLatinName(String ln) { commonName = ln; } public void setFamily(String f) { family = f; } public void setOrder(String o) { order = o; } } </code></pre> <p>My database schema looks like this:</p> <pre><code>CREATE TABLE species ( id serial NOT NULL, common_name text, latin_name text, order_name text, family_name text, CONSTRAINT id PRIMARY KEY (id) ) </code></pre> <p>species.hbn.xml looks like this:</p> <pre><code>&lt;?xml version="1.0"?&gt; &lt;!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN" "http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd"&gt; &lt;hibernate-mapping&gt; &lt;class name="springwildlife.Species" table="species"&gt; &lt;id name="id" type="java.lang.Long" column="id" &gt; &lt;generator class="native"&gt; &lt;param name="sequence"&gt;species_id_seq&lt;/param&gt; &lt;/generator&gt; &lt;/id&gt; &lt;property name="commonName" type="java.lang.String"&gt; &lt;column name="common_name" /&gt; &lt;/property&gt; &lt;property name="latinName" type="java.lang.String"&gt; &lt;column name="latin_name"/&gt; &lt;/property&gt; &lt;property name="order" type="java.lang.String"&gt; &lt;column name="order_name"/&gt; &lt;/property&gt; &lt;property name="family" type="java.lang.String"&gt; &lt;column name="family_name"/&gt; &lt;/property&gt; &lt;/class&gt; &lt;/hibernate-mapping&gt; </code></pre> <p>My SpeciesLister instance gets a full slate of all the expected number of Species instances. However, when I examine the resultant Species instances, all their fields are null except for the id (long), all the others like familyName, latinName, commonName all are null in the mapped object.</p> <p>This is unexpected and I can't figure out why it is happening. Am I doing something wrong? </p> <p>I'm suspicious about two things, but I'm not sure of what to make of them:</p> <ol> <li><p>I think the fact that the id is being property set, but not the other string fields might be a clue.</p></li> <li><p>I suspect something might be wrong with the way I'm casting the objects into a list of Species instances.</p></li> </ol>
 

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