org.apache.avro.reflect
Class ReflectData

java.lang.Object
  org.apache.avro.generic.GenericData
      org.apache.avro.specific.SpecificData
          org.apache.avro.reflect.ReflectData

Direct Known Subclasses:

ReflectData.AllowNull

public class ReflectData
extends SpecificData

Utilities to use existing Java classes and interfaces via reflection.

Nested Class Summary

static class

ReflectData.AllowNull ReflectData implementation that permits null field values.

Nested classes/interfaces inherited from class org.apache.avro.generic.GenericData

GenericData.Array<T>, GenericData.EnumSymbol, GenericData.Fixed, GenericData.Record

Constructor Summary

protected

ReflectData()

Method Summary

int	compare(Object o1, Object o2, Schema s) Compare objects according to their schema.
protected Schema	createFieldSchema(Field field, Map<String,Schema> names) Create a schema for a field.
protected Schema	createSchema(Type type, Map<String,Schema> names) Create the schema for a Java type.
static ReflectData	get() Return the singleton instance.
Class	getClass(Schema schema) Return the class that implements a schema, or null if none exists.
Object	getField(Object record, String name, int position) Called by GenericDatumReader.readRecord(java.lang.Object, org.apache.avro.Schema, org.apache.avro.io.ResolvingDecoder) to retrieve a record field value from a reused instance.
Protocol	getProtocol(Class iface) Return the protocol for a Java interface.
protected Schema	getRecordSchema(Object record) Called to obtain the schema of a record.
protected boolean	isArray(Object datum) Called by the default implementation of GenericData.instanceOf(org.apache.avro.Schema, java.lang.Object).
protected boolean	isBytes(Object datum) Called by the default implementation of GenericData.instanceOf(org.apache.avro.Schema, java.lang.Object).
protected boolean	isRecord(Object datum) Called by the default implementation of GenericData.instanceOf(org.apache.avro.Schema, java.lang.Object).
static Schema	makeNullable(Schema schema) Create and return a union of the null schema and the provided schema.
void	setField(Object record, String name, int position, Object o) Called by GenericDatumReader.readRecord(java.lang.Object, org.apache.avro.Schema, org.apache.avro.io.ResolvingDecoder) to set a record fields value to a record instance.
boolean	validate(Schema schema, Object datum) Returns true if a Java datum matches a schema.

Methods inherited from class org.apache.avro.specific.SpecificData

getClassName, getEnumSchema, getSchema, isEnum

Methods inherited from class org.apache.avro.generic.GenericData

getFixedSchema, hashCode, hashCodeAdd, induce, instanceOf, isFixed, isMap, isString, resolveUnion, toString, toString

Methods inherited from class java.lang.Object

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

Constructor Detail

ReflectData

protected ReflectData()

Method Detail

get

public static ReflectData get()

Return the singleton instance.

setField

public void setField(Object record,
                     String name,
                     int position,
                     Object o)

Description copied from class: GenericData

Called by GenericDatumReader.readRecord(java.lang.Object, org.apache.avro.Schema, org.apache.avro.io.ResolvingDecoder) to set a record fields value to a record instance. The default implementation is for IndexedRecord.

Overrides:

setField in class GenericData

getField

public Object getField(Object record,
                       String name,
                       int position)

Description copied from class: GenericData

Called by GenericDatumReader.readRecord(java.lang.Object, org.apache.avro.Schema, org.apache.avro.io.ResolvingDecoder) to retrieve a record field value from a reused instance. The default implementation is for IndexedRecord.

Overrides:

getField in class GenericData

isRecord

protected boolean isRecord(Object datum)

Description copied from class: GenericData

Called by the default implementation of GenericData.instanceOf(org.apache.avro.Schema, java.lang.Object).

Overrides:

isRecord in class GenericData

isArray

protected boolean isArray(Object datum)

Description copied from class: GenericData

Called by the default implementation of GenericData.instanceOf(org.apache.avro.Schema, java.lang.Object).

Overrides:

isArray in class GenericData

isBytes

protected boolean isBytes(Object datum)

Description copied from class: GenericData

Called by the default implementation of GenericData.instanceOf(org.apache.avro.Schema, java.lang.Object).

Overrides:

isBytes in class GenericData

getRecordSchema

protected Schema getRecordSchema(Object record)

Description copied from class: GenericData

Called to obtain the schema of a record. By default calls {GenericContainer#getSchema(). May be overridden for alternate record representations.

Overrides:

getRecordSchema in class GenericData

validate

public boolean validate(Schema schema,
                        Object datum)

Description copied from class: GenericData

Returns true if a Java datum matches a schema.

Overrides:

validate in class GenericData

getClass

public Class getClass(Schema schema)

Description copied from class: SpecificData

Return the class that implements a schema, or null if none exists.

Overrides:

getClass in class SpecificData

createSchema

protected Schema createSchema(Type type,
                              Map<String,Schema> names)

Description copied from class: SpecificData

Create the schema for a Java type.

Overrides:

createSchema in class SpecificData

makeNullable

public static Schema makeNullable(Schema schema)

Create and return a union of the null schema and the provided schema.

createFieldSchema

protected Schema createFieldSchema(Field field,
                                   Map<String,Schema> names)

Create a schema for a field.

getProtocol

public Protocol getProtocol(Class iface)

Return the protocol for a Java interface.

Note that this requires that Paranamer is run over compiled interface declarations, since Java 6 reflection does not provide access to method parameter names. See Avro's build.xml for an example.

Overrides:

getProtocol in class SpecificData

compare

public int compare(Object o1,
                   Object o2,
                   Schema s)

Description copied from class: GenericData

Compare objects according to their schema. If equal, return zero. If greater-than, return 1, if less than return -1. Order is consistent with that of BinaryData.compare(byte[], int, byte[], int, Schema).

Overrides:

compare in class SpecificData