org.apache.ambari.server.collections.functors

Class EqualsPredicate

java.lang.Object

org.apache.ambari.server.collections.Predicate

org.apache.ambari.server.collections.functors.EqualsPredicate

All Implemented Interfaces:

org.apache.commons.collections.Predicate

public class EqualsPredicate
extends Predicate

EqualsPredicate wraps EqualPredicate to provide additional functionality like serializing to and from a Map and JSON formatted data as well as obtaining data using a ContextTransformer

Field Summary

Fields

Modifier and Type	Field and Description
static String	NAME The name of this Predicate implementation

Constructor Summary

Constructors

Constructor and Description
EqualsPredicate(ContextTransformer transformer, String value) Constructor.

Method Summary

Modifier and Type	Method and Description
boolean	equals(Object obj)
boolean	evaluate(Object o)
boolean	evaluateTransformedData(Object data) Abstract method used internally to process the evaluate(Object) logic after the input data is transformed.
static EqualsPredicate	fromMap(Map<String,Object> map) Creates a new EqualsPredicate using the given Map of data.
String	getContextKey() Gets the context key assigned to the ContextTransformer.
ContextTransformer	getTransformer() Gets the Transformer
String	getValue() Gets the test value
int	hashCode()
void	setTransformer(ContextTransformer transformer) Sets the Transformer
Map<String,Object>	toMap() Serialize this Predicate to a Map

Methods inherited from class org.apache.ambari.server.collections.Predicate

getName, toJSON

Methods inherited from class java.lang.Object

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

Field Detail

NAME

public static final String NAME

The name of this Predicate implementation

See Also:

Constant Field Values

Constructor Detail

EqualsPredicate

public EqualsPredicate(ContextTransformer transformer,
                       String value)

Constructor.

Parameters:

transformer - the ContextTransformer

value - the value to test

Method Detail

fromMap

public static EqualsPredicate fromMap(Map<String,Object> map)

Creates a new EqualsPredicate using the given Map of data.

It is expected that the map contains a single Map.Entry where the key name is "equals" and the value is a Collection of 2 Strings. The first value should be the key to use when retrieving data from the context, which should resolve to a String (or null). The second value should be the value to use when checking for equality.

Returns:

a new EqualsPredicate

getValue

public String getValue()

Gets the test value

Returns:

a string

toMap

public Map<String,Object> toMap()

Description copied from class: Predicate

Serialize this Predicate to a Map

Specified by:

toMap in class Predicate

Returns:

a Map

evaluateTransformedData

public boolean evaluateTransformedData(Object data)

Abstract method used internally to process the evaluate(Object) logic after the input data is transformed.

Parameters:

data - the transformed data to use

Returns:

the result of the evaluation (true, false)

See Also:

Predicate.evaluate(Object)

getTransformer

public ContextTransformer getTransformer()

Gets the Transformer

Returns:

the assigned ContextTransformer

setTransformer

public void setTransformer(ContextTransformer transformer)

Sets the Transformer

Parameters:

transformer - a ContextTransformer

getContextKey

public String getContextKey()

Gets the context key assigned to the ContextTransformer.

This key is used to identify which value from the context a passed to the Predicate.evaluate(Object) method

Returns:

a key name

evaluate

public boolean evaluate(Object o)

hashCode

public int hashCode()

Overrides:

hashCode in class Predicate

equals

public boolean equals(Object obj)

Overrides:

equals in class Predicate