XmlWriteTransformer (EclipseLink 2.7.15, API Reference)

```
@Target({METHOD,FIELD})
@Retention(RUNTIME)
public @interface XmlWriteTransformer
```
Annotation for org.eclipse.persistence.mappings.oxm.XMLTransformationMapping. WriteTransformer defines transformation of the attribute value to a single XML value (XPath is specified in the WriteTransformer). A single XmlWriteTransformer may be specified directly on the method or attribute. Multiple XmlWriteTransformers should be wrapped into XmlWriteTransformers annotation. No XmlWriteTransformers specified for read-only mapping. Unless the XMLTransformationMapping is write-only, it should have a ReadTransformer, it defines transformation of XML value(s) into attribute value.

See Also:

XmlReadTransformer, XmlTransformation, XmlWriteTransformers

Required Element Summary

Required Elements
Modifier and Type Required Element Description

java.lang.String xmlPath
Specify here the XPath into which the value should be written.

Optional Element Summary

Optional Elements
Modifier and Type	Optional Element	Description
`java.lang.String`	`method`	The mapped class must have a method with this name which returns a value to be written into the XML document.
`java.lang.Class<? extends FieldTransformer>`	`transformerClass`	User-defined class that must implement the org.eclipse.persistence.mappings.transformers.FieldTransformer interface.

- Element Detail
  - xmlPath
```
java.lang.String xmlPath
```
    Specify here the XPath into which the value should be written. The only case when this could be skipped is if a single WriteTransformer annotates an attribute - the attribute's name will be used as an element name.
- - transformerClass
```
java.lang.Class<? extends FieldTransformer> transformerClass
```
    User-defined class that must implement the org.eclipse.persistence.mappings.transformers.FieldTransformer interface. The class will be instantiated, its buildFieldValue will be used to create the value to be written into XML document. Either transformerClass or method must be specified, but not both.
    
    Default:
    
    org.eclipse.persistence.mappings.transformers.FieldTransformer.class
- - method
```
java.lang.String method
```
    The mapped class must have a method with this name which returns a value to be written into the XML document. The method may require an XmlTransient annotation to avoid being mapped as an XmlElement by default. Either transformerClass or method must be specified, but not both.
    
    Default:
    
    ""