com.linkedin.feathr.offline.mvel

Class MvelContext

java.lang.Object

com.linkedin.feathr.offline.mvel.MvelContext

public class MvelContext
extends java.lang.Object

Some MVEL hackery to enable use in Feathr. MVEL is an open-source expression language and runtime that makes it easy to write concise statements that operate on structured data objects (such as Avro records), among other things.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	MvelContext.GenericRecordPropertyHandler Allows easy access to the properties of GenericRecord object from MVEL.

Method Summary

Modifier and Type	Method and Description
static void	ensureInitialized()
static java.lang.Object	executeExpressionWithPluginSupport(java.lang.Object compiledExpression, java.lang.Object ctx, com.linkedin.feathr.offline.mvel.plugins.FeathrExpressionExecutionContext mvelContext) Evaluate MVEL expression as per MVEL.executeExpression(Object, Object), with added support for com.linkedin.feathr.offline.mvel.plugins.FeathrMvelPluginContext.
static java.lang.Object	executeExpressionWithPluginSupportWithFactory(java.lang.Object compiledExpression, java.lang.Object ctx, org.mvel2.integration.VariableResolverFactory variableResolverFactory, com.linkedin.feathr.offline.mvel.plugins.FeathrExpressionExecutionContext mvelContext) Evaluate MVEL expression as per MVEL.executeExpression(Object, Object, VariableResolverFactory), with added support for com.linkedin.feathr.offline.mvel.plugins.FeathrMvelPluginContext.
static org.mvel2.ParserContext	newParserContext() Gives access to our helper methods from within an MVEL expression.

Methods inherited from class java.lang.Object

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

Method Detail

ensureInitialized

public static void ensureInitialized()

newParserContext

public static org.mvel2.ParserContext newParserContext()

Gives access to our helper methods from within an MVEL expression.

Returns:

an MVEL ParserContext in which our helper UDFs are available

executeExpressionWithPluginSupport

public static java.lang.Object executeExpressionWithPluginSupport(java.lang.Object compiledExpression,
                                                                  java.lang.Object ctx,
                                                                  com.linkedin.feathr.offline.mvel.plugins.FeathrExpressionExecutionContext mvelContext)

Evaluate MVEL expression as per MVEL.executeExpression(Object, Object), with added support for com.linkedin.feathr.offline.mvel.plugins.FeathrMvelPluginContext. (Output objects that can be converted to FeatureValue via plugins, will be converted after MVEL returns.)

executeExpressionWithPluginSupportWithFactory

public static java.lang.Object executeExpressionWithPluginSupportWithFactory(java.lang.Object compiledExpression,
                                                                             java.lang.Object ctx,
                                                                             org.mvel2.integration.VariableResolverFactory variableResolverFactory,
                                                                             com.linkedin.feathr.offline.mvel.plugins.FeathrExpressionExecutionContext mvelContext)

Evaluate MVEL expression as per MVEL.executeExpression(Object, Object, VariableResolverFactory), with added support for com.linkedin.feathr.offline.mvel.plugins.FeathrMvelPluginContext. (Output objects that can be converted to FeatureValue via plugins, will be converted after MVEL returns.)