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POJAXB: How to marshal objects in lists?
 

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    <p>Perhaps a stupid question: I have a <code>List</code> of type <code>&lt;Data&gt;</code> which I want to marshal into a XML file. This is my class <code>Database</code> containing an <code>ArrayList</code>...</p> <pre class="lang-java prettyprint-override"><code>@XmlRootElement public class Database { List&lt;Data&gt; records = new ArrayList&lt;Data&gt;(); public List&lt;Data&gt; getRecords() { return records; } public void setRecords(List&lt;Data&gt; records) { this.records = records; } } </code></pre> <p>...and this is class Data:</p> <pre class="lang-java prettyprint-override"><code>// @XmlRootElement public class Data { String name; String address; public String getName() { return name; } public void setName(String name) { this.name = name; } public String getAddress() { return address; } public void setAddress(String address) { this.address = address; } } </code></pre> <p>Using the following test class...</p> <pre class="lang-java prettyprint-override"><code>public class Test { public static void main(String args[]) throws Exception { Data data1 = new Data(); data1.setName("Peter"); data1.setAddress("Cologne"); Data data2 = new Data(); data2.setName("Mary"); data2.setAddress("Hamburg"); Database database = new Database(); database.getRecords().add(data1); database.getRecords().add(data2); JAXBContext context = JAXBContext.newInstance(Database.class); Marshaller marshaller = context.createMarshaller(); marshaller.setProperty(Marshaller.JAXB_FORMATTED_OUTPUT, true); marshaller.marshal(database, new FileWriter("test.xml")); } } </code></pre> <p>...I got the result:</p> <pre class="lang-xml prettyprint-override"><code>&lt;database&gt; &lt;records&gt; &lt;address&gt;Cologne&lt;/address&gt; &lt;name&gt;Peter&lt;/name&gt; &lt;/records&gt; &lt;records&gt; &lt;address&gt;Hamburg&lt;/address&gt; &lt;name&gt;Mary&lt;/name&gt; &lt;/records&gt; &lt;/database&gt; </code></pre> <p>But that's not what I was expecting, i.e. all tags for <code>&lt;Data&gt;</code> objects are missing. I am looking for a way to export the data in the following structure, but I don't know how to achieve this:</p> <pre class="lang-xml prettyprint-override"><code>&lt;database&gt; &lt;records&gt; &lt;data&gt; &lt;address&gt;Cologne&lt;/address&gt; &lt;name&gt;Peter&lt;/name&gt; &lt;/data&gt; &lt;data&gt; &lt;address&gt;Hamburg&lt;/address&gt; &lt;name&gt;Mary&lt;/name&gt; &lt;/data&gt; &lt;/records&gt; &lt;/database&gt; </code></pre> <hr> <p>One additional question: if I want to deal with the problem <strong>without</strong> using <code>@XmlElementWrapper</code> and <code>@XmlElement</code> annotations, I can introduce an intermediary class</p> <pre class="lang-java prettyprint-override"><code>public class Records { List&lt;Data&gt; data = new ArrayList&lt;Data&gt;(); public List&lt;Data&gt; getData() { return data; } public void setData(List&lt;Data&gt; data) { this.data = data; } } </code></pre> <p>used by the modified base class</p> <pre class="lang-java prettyprint-override"><code>@XmlRootElement public class Database { Records records = new Records(); public Records getRecords() { return records; } public void setRecords(Records records) { this.records = records; } } </code></pre> <p>in a slightly modified <code>Test</code> class:</p> <pre class="lang-java prettyprint-override"><code>... Database database = new Database(); database.getRecords().getData().add(data1); database.getRecords().getData().add(data2); ... </code></pre> <p>The result also is:</p> <pre class="lang-xml prettyprint-override"><code>&lt;database&gt; &lt;records&gt; &lt;data&gt; &lt;address&gt;Cologne&lt;/address&gt; &lt;name&gt;Peter&lt;/name&gt; &lt;/data&gt; &lt;data&gt; &lt;address&gt;Hamburg&lt;/address&gt; &lt;name&gt;Mary&lt;/name&gt; &lt;/data&gt; &lt;/records&gt; &lt;/database&gt; </code></pre> <p>Is this the <strong>recommended</strong> way to create a Java class structure according to the XML file structure above?</p>
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    1. COI don't see you using `DataList` in your test class.
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    2. COPardon me - i copied & pasted the wrong class... It's now corrected in the example above.
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