Package org.elasticsearch.common.xcontent

Interface XContentBuilderExtension

public interface XContentBuilderExtension

This interface provides a way for non-JDK classes to plug in a way to serialize to xcontent. It is greatly preferred that you implement ToXContentFragment in the class for encoding, however, in some situations you may not own the class, in which case you can add an implementation here for encoding it.

Method Summary

Modifier and Type	Method	Description
java.util.Map<java.lang.Class<?>,java.util.function.Function<java.lang.Object,java.lang.Object>>	getDateTransformers()	Used for plugging a transformer for a date or time type object into a String (or other encodable object).
java.util.Map<java.lang.Class<?>,XContentBuilder.HumanReadableTransformer>	getXContentHumanReadableTransformers()	Used for plugging in a human readable version of a class's encoding.
java.util.Map<java.lang.Class<?>,XContentBuilder.Writer>	getXContentWriters()	Used for plugging in a generic writer for a class, for example, an example implementation:

Method Detail

getXContentWriters

java.util.Map<java.lang.Class<?>,XContentBuilder.Writer> getXContentWriters()

Used for plugging in a generic writer for a class, for example, an example implementation:

 
     Map<Class<?>, XContentBuilder.Writer> addlWriters = new HashMap<>();
     addlWriters.put(BytesRef.class, (builder, value) -> b.value(((BytesRef) value).utf8String()));
     return addlWriters;
 
 

Returns:

a map of class name to writer

getXContentHumanReadableTransformers

java.util.Map<java.lang.Class<?>,XContentBuilder.HumanReadableTransformer> getXContentHumanReadableTransformers()

Used for plugging in a human readable version of a class's encoding. It is assumed that the human readable equivalent is always behind the toString() method, so this transformer returns the raw value to be used. An example implementation:

 
     Map<Class<?>, XContentBuilder.HumanReadableTransformer> transformers = new HashMap<>();
     transformers.put(ByteSizeValue.class, (value) -> ((ByteSizeValue) value).bytes());
 
 

Returns:

a map of class name to transformer used to retrieve raw value

getDateTransformers

java.util.Map<java.lang.Class<?>,java.util.function.Function<java.lang.Object,java.lang.Object>> getDateTransformers()

Used for plugging a transformer for a date or time type object into a String (or other encodable object). For example:

 
     final DateTimeFormatter datePrinter = ISODateTimeFormat.dateTime().withZone(DateTimeZone.UTC);
     Map<Class<?>, Function<Object, Object>> transformers = new HashMap<>();
     transformers.put(Date.class, d -> datePrinter.print(((Date) d).getTime()));