org.apache.hadoop.hive.serde2.objectinspector
Interface ObjectInspector
- All Known Subinterfaces:
- BooleanObjectInspector, ByteObjectInspector, DoubleObjectInspector, FloatObjectInspector, IntObjectInspector, ListObjectInspector, LongObjectInspector, MapObjectInspector, PrimitiveObjectInspector, SettableBooleanObjectInspector, SettableByteObjectInspector, SettableDoubleObjectInspector, SettableFloatObjectInspector, SettableIntObjectInspector, SettableListObjectInspector, SettableLongObjectInspector, SettableMapObjectInspector, SettableShortObjectInspector, SettableStringObjectInspector, ShortObjectInspector, StringObjectInspector, VoidObjectInspector
- All Known Implementing Classes:
- AbstractPrimitiveJavaObjectInspector, AbstractPrimitiveLazyObjectInspector, AbstractPrimitiveObjectInspector, AbstractPrimitiveWritableObjectInspector, JavaBooleanObjectInspector, JavaByteObjectInspector, JavaDoubleObjectInspector, JavaFloatObjectInspector, JavaIntObjectInspector, JavaLongObjectInspector, JavaShortObjectInspector, JavaStringObjectInspector, JavaVoidObjectInspector, LazyBinaryListObjectInspector, LazyBinaryMapObjectInspector, LazyBinaryStructObjectInspector, LazyBooleanObjectInspector, LazyByteObjectInspector, LazyDoubleObjectInspector, LazyFloatObjectInspector, LazyIntObjectInspector, LazyListObjectInspector, LazyLongObjectInspector, LazyMapObjectInspector, LazyShortObjectInspector, LazySimpleStructObjectInspector, LazyStringObjectInspector, LazyVoidObjectInspector, MetadataListStructObjectInspector, ReflectionStructObjectInspector, SettableStructObjectInspector, StandardListObjectInspector, StandardMapObjectInspector, StandardStructObjectInspector, StructObjectInspector, UnionStructObjectInspector, WritableBooleanObjectInspector, WritableByteObjectInspector, WritableDoubleObjectInspector, WritableFloatObjectInspector, WritableIntObjectInspector, WritableLongObjectInspector, WritableShortObjectInspector, WritableStringObjectInspector, WritableVoidObjectInspector
public interface ObjectInspector
ObjectInspector helps us to look into the internal structure of a complex
object.
A (probably configured) ObjectInspector instance stands for a specific type
and a specific way to store the data of that type in the memory.
For native java Object, we can directly access the internal structure through
member fields and methods. ObjectInspector is a way to delegate that functionality
away from the Object, so that we have more control on the behavior of those actions.
An efficient implementation of ObjectInspector should rely on factory, so that we can
make sure the same ObjectInspector only has one instance. That also makes sure
hashCode() and equals() methods of java.lang.Object directly works for ObjectInspector
as well.
Method Summary |
ObjectInspector.Category |
getCategory()
An ObjectInspector must inherit from one of the following interfaces
if getCategory() returns:
PRIMITIVE: PrimitiveObjectInspector
LIST: ListObjectInspector
MAP: MapObjectInspector
STRUCT: StructObjectInspector |
String |
getTypeName()
Returns the name of the data type that is inspected by this ObjectInspector. |
getTypeName
String getTypeName()
- Returns the name of the data type that is inspected by this ObjectInspector.
This is used to display the type information to the user.
For primitive types, the type name is standardized.
For other types, the type name can be something like "list", "map",
java class names, or user-defined type names similar to typedef.
getCategory
ObjectInspector.Category getCategory()
- An ObjectInspector must inherit from one of the following interfaces
if getCategory() returns:
PRIMITIVE: PrimitiveObjectInspector
LIST: ListObjectInspector
MAP: MapObjectInspector
STRUCT: StructObjectInspector
Copyright © 2009 The Apache Software Foundation