secondaryindex

Class Binding

java.lang.Object

secondaryindex.Binding

public class Binding
extends Object

Implements a generic conversion between Value and Avro schema instances.

The class is used by IndexViewService to parse the Value part of KV pairs. It also supplies some general conversion methods for user records with different schemas. The example defines a BillInfo as its primary DB record schema which is defined in the resource file "billinfo-schema.avsc".

Constructor Summary

Constructors

Constructor and Description
Binding(AvroCatalog avroCatalog)

Method Summary

Methods

Modifier and Type	Method and Description
Schema	getSchema(String schemaName) Returns the Schema object for the given schema name.
String	getSchemaName(Value value) Returns the schema name of value.
List<Object>	toFields(Value value, List<String> fieldNames) Given a list of Avro field names, extracts the field values from the value parameter.
GenericRecord	toObject(Value value) Returns the deserialized GenericRecord instance.
Value	toValue(GenericRecord record) Returns the Value that conforms to the schema of the given GenericRecord.

Methods inherited from class java.lang.Object

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

Constructor Detail

Binding

public Binding(AvroCatalog avroCatalog)

Method Detail

toValue

public Value toValue(GenericRecord record)

Returns the Value that conforms to the schema of the given GenericRecord.

Parameters:

record -

Returns:

Value

toObject

public GenericRecord toObject(Value value)

Returns the deserialized GenericRecord instance. If the given Value is not in Avro format then null will be returned.

Parameters:

value -

Returns:

a GenericRecord or null if the given Value is not an Avro data.

toFields

public List<Object> toFields(Value value,
                    List<String> fieldNames)

Given a list of Avro field names, extracts the field values from the value parameter. null is returned if the given Value is not valid Avro data.

Parameters:

value -

fieldNames - the Avro field names to extract from value. The fields must be contained in the value's schema definition.

Returns:

a list holding field values in the same order as the input field name list. null is return if the given Value is not valid Avro data.

getSchemaName

public String getSchemaName(Value value)

Returns the schema name of value. If the value is not an Avro data then null is returned.

Parameters:

value -

Returns:

null if the given Value is not valid Avro data.

getSchema

public Schema getSchema(String schemaName)

Returns the Schema object for the given schema name.

Parameters:

schemaName -

Returns:

Schema