writexml.html

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  <h3>
    e7.  
    Serializing a Bean to XML</h3>

The <code>XMLEncoder</code> class serializes an object in similar fashion to
<code>java.io.ObjectOutput</code>. However, unlike <code>ObjectOutput</code>, which
persists all non-transient private and public data, the
<code>XMLEncoder</code> only persists the value of public properties. In
particular, for every public property, <code>XMLEncoder</code> calls its
getter method and persists the returned value. In deserialization, a
newly created object is initialized with these persisted property
values.  Therefore, any private state that is not associated with a
property will, by default, not be persisted.
 
<P>
See also <a href="../java.beans/ReadXml.html" class="eglink"><font size="-1"><b>e8</b> Deserializing a Bean from XML</font></a>.


<pre>
    // Create an object and set properties
    <font color="#0066ff"><i>MyClass</i></font> o = new <font color="#0066ff"><i>MyClass</i></font>();
    o.setProp(<font color="#0066ff"><i>1</i></font>);
    o.setProps(new int[]{<font color="#0066ff"><i>1, 2, 3</i></font>});
    
    try {
        // Serialize object into XML
        XMLEncoder encoder = new XMLEncoder(new BufferedOutputStream(
            new FileOutputStream(<font color="#0066ff"><i>"outfilename.xml"</i></font>)));
        encoder.writeObject(o);
        encoder.close();
    } catch (FileNotFoundException e) {
    }
</pre>


<pre>
    // This class defines two properties - prop and props
    public class MyClass {
        // The prop property
        int i;
        public int getProp() {
            return i;
        }
        public void setProp(int i) {
            this.i = i;
        }
    
        // The props property
        int[] iarray = new int[0];
        public int[] getProps() {
            return iarray;
        }
        public void setProps(int[] iarray) {
            this.iarray = iarray;
        }
    }
</pre>
Here is the XML data:

<pre>
    &lt;?xml version="1.0" encoding="UTF-8"?&gt;
    &lt;java version="1.4.0" class="java.beans.XMLDecoder"&gt;
        &lt;object class="MyClass"&gt;
            &lt;void property="prop"&gt;
                &lt;int&gt;1&lt;/int&gt;
            &lt;/void&gt;
            &lt;void property="props"&gt;
                &lt;array class="int" length="3"&gt;
                    &lt;void index="0"&gt;
                        &lt;int&gt;1&lt;/int&gt;
                    &lt;/void&gt;
                    &lt;void index="1"&gt;
                        &lt;int&gt;2&lt;/int&gt;
                    &lt;/void&gt;
                    &lt;void index="2"&gt;
                        &lt;int&gt;3&lt;/int&gt;
                    &lt;/void&gt;
                &lt;/array&gt;
            &lt;/void&gt;
        &lt;/object&gt;
    &lt;/java&gt;
</pre>
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            &nbsp;Related Examples
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e8. <a class="eglink" href="ReadXml.html?l=rel">
    Deserializing a Bean from XML
</a>
<br>

e9. <a class="eglink" href="MakeTrans.html?l=rel">
    Preventing a Bean Property from Being Serialized to XML
</a>
<br>

e10. <a class="eglink" href="Immute.html?l=rel">
    Serializing an Immutable Bean Property to XML
</a>
<br>


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<br>
        See also: 
<a class="eglink" href="/egs/java.beans/pkg.html?l=rel#Events">
    Events
</a>&nbsp;&nbsp;

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