org.apache.ambari.server.collections.functors

Class ContextTransformer

java.lang.Object

org.apache.ambari.server.collections.functors.ContextTransformer

All Implemented Interfaces:

org.apache.commons.collections.Transformer

public class ContextTransformer
extends Object
implements org.apache.commons.collections.Transformer

ContextTransformer is a Transformer implementation that traverses a Map of Maps to find the value related to the specified key.

This implementation first checks the context map for the explicit key. If the key exists, it returns the value associated with it. If the key does not exist and appears to represent a path via "/"-delimited keys (configurations/service-site/property_name), the path is traversed recursively looking for the requested data.

Example context:

 |- services : [set of services]
 |
 |- configurations
 |  |- service-site
 |  |  |- property : [value]
 |
 |- key/looks/like/path : [value2]
 

• If the key was services, [set of services] would be returned
• If the key was configurations/service-site/property, value would be returned
• If the key was configurations/service-site, [map of service-site properties] would be returned
• If the key was key/looks/like/path, value2 would be returned

Constructor Summary

Constructors

Constructor and Description
ContextTransformer(String key) Constructor.

Method Summary

Modifier and Type	Method and Description
boolean	equals(Object obj)
String	getKey() Returns the key this transformer is using to search for data
int	hashCode()
Object	transform(Object o)

Methods inherited from class java.lang.Object

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

Constructor Detail

ContextTransformer

public ContextTransformer(String key)

Constructor.

Parameters:

key - the key to search for

Method Detail

getKey

public String getKey()

Returns the key this transformer is using to search for data

Returns:

a string

transform

public Object transform(Object o)

Specified by:

transform in interface org.apache.commons.collections.Transformer

hashCode

public int hashCode()

Overrides:

hashCode in class Object

equals

public boolean equals(Object obj)

Overrides:

equals in class Object