org.apache.beam.sdk.schemas

Class JavaBeanSchema

java.lang.Object

org.apache.beam.sdk.schemas.GetterBasedSchemaProvider

org.apache.beam.sdk.schemas.JavaBeanSchema

All Implemented Interfaces:

java.io.Serializable, SchemaProvider

@Experimental(value=SCHEMAS)
public class JavaBeanSchema
extends GetterBasedSchemaProvider

A SchemaProvider for Java Bean objects.

This provider finds (recursively) all public getters and setters in a Java object, and creates schemas and rows that bind to those fields. The field order in the schema is not guaranteed to match the method order in the class. The Java object is expected to have implemented a correct .equals() and .hashCode methods The equals method must be completely determined by the schema fields. i.e. if the object has hidden fields that are not reflected in the schema but are compared in equals, then results will be incorrect.

TODO: Validate equals() method is provided, and if not generate a "slow" equals method based on the schema.

See Also:

Serialized Form

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	JavaBeanSchema.GetterTypeSupplier FieldValueTypeSupplier that's based on getter methods.
static class	JavaBeanSchema.SetterTypeSupplier FieldValueTypeSupplier that's based on setter methods.

Constructor Summary

Constructors

Constructor and Description
JavaBeanSchema()

Method Summary

Modifier and Type	Method and Description
boolean	equals(@Nullable java.lang.Object obj)
java.util.List<FieldValueGetter>	fieldValueGetters(java.lang.Class<?> targetClass, Schema schema) Implementing class should override to return FieldValueGetters.
java.util.List<FieldValueTypeInformation>	fieldValueTypeInformations(java.lang.Class<?> targetClass, Schema schema) Implementing class should override to return a list of type-informations.
int	hashCode()
<T> Schema	schemaFor(TypeDescriptor<T> typeDescriptor) Lookup a schema for the given type.
SchemaUserTypeCreator	schemaTypeCreator(java.lang.Class<?> targetClass, Schema schema) Implementing class should override to return a constructor.

Methods inherited from class org.apache.beam.sdk.schemas.GetterBasedSchemaProvider

fromRowFunction, toRowFunction

Methods inherited from class java.lang.Object

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

Constructor Detail

JavaBeanSchema

public JavaBeanSchema()

Method Detail

schemaFor

public <T> Schema schemaFor(TypeDescriptor<T> typeDescriptor)

Description copied from interface: SchemaProvider

Lookup a schema for the given type. If no schema exists, returns null.

fieldValueGetters

public java.util.List<FieldValueGetter> fieldValueGetters(java.lang.Class<?> targetClass,
                                                          Schema schema)

Description copied from class: GetterBasedSchemaProvider

Implementing class should override to return FieldValueGetters.

Specified by:

fieldValueGetters in class GetterBasedSchemaProvider

fieldValueTypeInformations

public java.util.List<FieldValueTypeInformation> fieldValueTypeInformations(java.lang.Class<?> targetClass,
                                                                            Schema schema)

Description copied from class: GetterBasedSchemaProvider

Implementing class should override to return a list of type-informations.

Specified by:

fieldValueTypeInformations in class GetterBasedSchemaProvider

schemaTypeCreator

public SchemaUserTypeCreator schemaTypeCreator(java.lang.Class<?> targetClass,
                                               Schema schema)

Description copied from class: GetterBasedSchemaProvider

Implementing class should override to return a constructor.

Specified by:

schemaTypeCreator in class GetterBasedSchemaProvider

hashCode

public int hashCode()

Overrides:

hashCode in class GetterBasedSchemaProvider

equals

public boolean equals(@Nullable java.lang.Object obj)

Overrides:

equals in class GetterBasedSchemaProvider