org.helenus.driver.impl

Class DataTypeImpl

java.lang.Object

org.helenus.driver.impl.DataTypeImpl

public class DataTypeImpl
extends Object

The DataTypeImpl class provides definition for Cassandra data types used for columns when one cannot rely on the default behavior where the type is inferred from the field type.

Since:

1.0

Version:

1 - Jan 19, 2015 - paouelle - Creation

Author:

The Helenus Driver Project Authors

Copyright:

2015-2015 The Helenus Driver Project Authors

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	DataTypeImpl.Definition The Definition class provides a data type definition for a CQL data type.

Constructor Summary

Constructors

Constructor and Description
DataTypeImpl()

Method Summary

Modifier and Type	Method and Description
static DataTypeImpl.Definition	inferDataTypeFrom(DataType type, Class<?> clazz) Infers the data type from the specified class' superclass.
static DataTypeImpl.Definition	inferDataTypeFrom(Field field) Infers the data type from the specified field.
static boolean	isAssignableFrom(CQLDataType type, Class<?> clazz) Determines if the given data type is either the same as or is a superclass or super interface of, the class or interface represented by the specified clazz parameter.
static boolean	isInstance(CQLDataType type, Object object) Determines if the given object is assignment compatible with this data type.
static Class<?>	unwrapOptionalIfPresent(Class<?> clazz, Type type) Unwraps the specific class if it is an Optional.

Methods inherited from class java.lang.Object

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

Constructor Detail

DataTypeImpl

public DataTypeImpl()

Method Detail

unwrapOptionalIfPresent

public static Class<?> unwrapOptionalIfPresent(Class<?> clazz,
                                               Type type)

Unwraps the specific class if it is an Optional.

Parameters:

clazz - the class to unwrap if required

type - the corresponding type for the class

Returns:

the element of the optional class if it is an optional otherwise the class itself

inferDataTypeFrom

public static DataTypeImpl.Definition inferDataTypeFrom(Field field)

Infers the data type from the specified field.

Parameters:

field - the field from which to infer the data type

Returns:

a non-null data type definition

Throws:

NullPointerException - if field is null

IllegalArgumentException - if the data type cannot be inferred from the field or it is persisted but the persister cannot be instantiate

inferDataTypeFrom

public static DataTypeImpl.Definition inferDataTypeFrom(DataType type,
                                                        Class<?> clazz)

Infers the data type from the specified class' superclass.

Parameters:

type - the collection type being inferred

clazz - the class from which to infer the data type of its superclass

Returns:

a non-null data type definition

Throws:

NullPointerException - if type or clazz is null

IllegalArgumentException - if the argument data type cannot be inferred from the superclass or the specified type is not a collection data type

isAssignableFrom

public static boolean isAssignableFrom(CQLDataType type,
                                       Class<?> clazz)

Determines if the given data type is either the same as or is a superclass or super interface of, the class or interface represented by the specified clazz parameter. It returns true if so; otherwise it returns false.

Parameters:

type - the data type to check

clazz - the class to check

Returns:

true if the given class can be assigned to the given data type

isInstance

public static boolean isInstance(CQLDataType type,
                                 Object object)

Determines if the given object is assignment compatible with this data type.

Parameters:

type - the data type to check

object - the object to check

Returns:

true if the given object can be assigned to a column of this data type; false otherwise