io.druid.query.extraction

Class JavascriptExtractionFn

java.lang.Object

io.druid.query.extraction.JavascriptExtractionFn

All Implemented Interfaces:

ExtractionFn

public class JavascriptExtractionFn
extends Object
implements ExtractionFn

Constructor Summary

Constructors

Constructor and Description
JavascriptExtractionFn(String function)

Method Summary

Methods

Modifier and Type	Method and Description
String	apply(long value)
String	apply(Object value) The "extraction" function.
String	apply(String value)
boolean	equals(Object o)
byte[]	getCacheKey() Returns a byte[] unique to all concrete implementations of DimExtractionFn.
String	getFunction()
int	hashCode()
boolean	preservesOrdering() Offers information on whether the extraction will preserve the original ordering of the values.
String	toString()

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Constructor Detail

JavascriptExtractionFn

public JavascriptExtractionFn(String function)

Method Detail

getFunction

public String getFunction()

getCacheKey

public byte[] getCacheKey()

Description copied from interface: ExtractionFn

Returns a byte[] unique to all concrete implementations of DimExtractionFn. This byte[] is used to generate a cache key for the specific query.

Specified by:

getCacheKey in interface ExtractionFn

Returns:

a byte[] unit to all concrete implements of DimExtractionFn

apply

public String apply(Object value)

Description copied from interface: ExtractionFn

The "extraction" function. This should map a value into some other String value. In order to maintain the "null and empty string are equivalent" semantics that Druid provides, the empty string is considered invalid output for this method and should instead return null. This is a contract on the method rather than enforced at a lower level in order to eliminate a global check for extraction functions that do not already need one.

Specified by:

apply in interface ExtractionFn

Parameters:

value - the original value of the dimension

Returns:

a value that should be used instead of the original

apply

public String apply(String value)

Specified by:

apply in interface ExtractionFn

apply

public String apply(long value)

Specified by:

apply in interface ExtractionFn

preservesOrdering

public boolean preservesOrdering()

Description copied from interface: ExtractionFn

Offers information on whether the extraction will preserve the original ordering of the values. Some optimizations of queries is possible if ordering is preserved. Null values *do* count towards ordering.

Specified by:

preservesOrdering in interface ExtractionFn

Returns:

true if ordering is preserved, false otherwise

toString

public String toString()

Overrides:

toString in class Object

equals

public boolean equals(Object o)

Overrides:

equals in class Object

hashCode

public int hashCode()

Overrides:

hashCode in class Object