org.datanucleus.store.rdbms.mapping.java

Class JavaTypeMapping

java.lang.Object

org.datanucleus.store.rdbms.mapping.java.JavaTypeMapping

Direct Known Subclasses:

MultiMapping, SerialisedLocalFileMapping, SingleCollectionMapping, SingleFieldMapping, SingleFieldMultiMapping

public abstract class JavaTypeMapping
extends Object

Representation of the mapping of a Java type. The java type maps to one or more column mappings. This means that a field/property in a java class can be mapped to many columns in a table. A JavaTypeMapping can exist in 2 forms

• Constructed for a field/property managed by a datastore container, and so has metadata/container information
• Constructed to represent a parameter in a query, so has no metadata and container information.

Field Summary

Fields

Modifier and Type	Field and Description
protected int	absFieldNumber Absolute field number for this mapping.
protected ColumnMapping[]	columnMappings The Column mappings for this Java type.
protected org.datanucleus.metadata.AbstractMemberMetaData	mmd MetaData for the field/property that we are mapping.
protected JavaTypeMapping	referenceMapping Mapping of the reference on the end of a bidirectional association.
protected org.datanucleus.metadata.FieldRole	roleForMember Role of the mapping for the field.
protected RDBMSStoreManager	storeMgr StoreManager for the datastore being used.
protected Table	table The Table storing this mapping.
protected String	type Actual type being mapped

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	JavaTypeMapping() Create a new empty JavaTypeMapping.

Method Summary

Modifier and Type	Method and Description
void	addColumnMapping(ColumnMapping cm) Method to add a column mapping
boolean	equals(Object obj) Equality operator.
protected String	failureMessage(String method) Utility to output any error message.
protected int	getAbsoluteFieldNumber()
boolean	getBoolean(org.datanucleus.ExecutionContext ec, ResultSet rs, int[] exprIndex) Obtains a value from datastoreResults at position specified by exprIndex.
byte	getByte(org.datanucleus.ExecutionContext ec, ResultSet rs, int[] exprIndex) Obtains a value from datastoreResults at position specified by exprIndex.
char	getChar(org.datanucleus.ExecutionContext ec, ResultSet rs, int[] exprIndex) Obtains a value from datastoreResults at position specified by exprIndex.
ColumnMapping	getColumnMapping(int index) Accessor for a column mapping
ColumnMapping[]	getColumnMappings() Accessor for the column mappings for this java type
protected static org.datanucleus.metadata.ColumnMetaData[]	getColumnMetaDataForMember(org.datanucleus.metadata.AbstractMemberMetaData mmd, org.datanucleus.metadata.FieldRole role) Convenience method to return the ColumnMetaData appropriate for this mapping.
double	getDouble(org.datanucleus.ExecutionContext ec, ResultSet rs, int[] exprIndex) Obtains a value from datastoreResults at position specified by exprIndex.
float	getFloat(org.datanucleus.ExecutionContext ec, ResultSet rs, int[] exprIndex) Obtains a value from datastoreResults at position specified by exprIndex.
int	getInt(org.datanucleus.ExecutionContext ec, ResultSet rs, int[] exprIndex) Obtains a value from datastoreResults at position specified by exprIndex.
abstract Class	getJavaType() Accessor for the java type being mapped.
String	getJavaTypeForColumnMapping(int index) Accessor for the name of the java-type actually used when mapping the particular column.
long	getLong(org.datanucleus.ExecutionContext ec, ResultSet rs, int[] exprIndex) Obtains a value from datastoreResults at position specified by exprIndex.
org.datanucleus.metadata.AbstractMemberMetaData	getMemberMetaData() Accessor for the MetaData of the field/property being mapped.
int	getNumberOfColumnMappings() Accessor for the number of column mappings.
Object	getObject(org.datanucleus.ExecutionContext ec, ResultSet rs, int[] exprIndex) Obtains a value from datastoreResults at position specified by exprIndex.
Object	getObject(org.datanucleus.ExecutionContext ec, ResultSet rs, int[] exprIndex, org.datanucleus.state.ObjectProvider ownerOP, int ownerFieldNumber) Obtains a value from datastoreResults at position specified by exprIndex.
JavaTypeMapping	getReferenceMapping() Accessor for the mapping at the other end of a relation when this field is part of a 1-1, 1-N, M-N (bidirectional) relation.
org.datanucleus.metadata.FieldRole	getRoleForMember() Accessor for the role of this mapping for the field/property.
short	getShort(org.datanucleus.ExecutionContext ec, ResultSet rs, int[] exprIndex) Obtains a value from datastoreResults at position specified by exprIndex.
RDBMSStoreManager	getStoreManager()
String	getString(org.datanucleus.ExecutionContext ec, ResultSet rs, int[] exprIndex) Obtains a value from datastoreResults at position specified by exprIndex.
Table	getTable() Accessor for the table.
String	getType() Accessor for the class name of the object that is being mapped here.
Object	getValueForColumnMapping(org.datanucleus.NucleusContext nucleusCtx, int index, Object value) Method to return the value to be stored in the specified column index given the overall value for this java type.
int	hashCode() Hash code function.
boolean	hasSimpleDatastoreRepresentation() Whether the mapping has a simple (single column) datastore representation.
boolean	includeInFetchStatement() Accessor for whether this mapping is to be included in any fetch statement.
boolean	includeInInsertStatement() Accessor for whether this mapping is to be included in the insert statement.
boolean	includeInUpdateStatement() Accessor for whether this mapping is to be included in the update statement.
void	initialize(org.datanucleus.metadata.AbstractMemberMetaData mmd, Table table, org.datanucleus.ClassLoaderResolver clr) Initialize this JavaTypeMapping for the supplied table and field/property metadata.
void	initialize(RDBMSStoreManager storeMgr, String type) Initialise this JavaTypeMapping with the given StoreManager for the given type.
boolean	isNullable() Accessor for whether this mapping is nullable
boolean	isSerialised() Convenience method to return if the (part of the) field being represented by this mapping is serialised.
boolean	representableAsStringLiteralInStatement() The vast majority of types can be added to a (SQL) statement in their String form and the statement would operate ok.
void	setAbsFieldNumber(int num)
void	setBoolean(org.datanucleus.ExecutionContext ec, PreparedStatement ps, int[] exprIndex, boolean value) Sets a value into datastoreStatement at position specified by exprIndex.
void	setByte(org.datanucleus.ExecutionContext ec, PreparedStatement ps, int[] exprIndex, byte value) Sets a value into datastoreStatement at position specified by exprIndex.
void	setChar(org.datanucleus.ExecutionContext ec, PreparedStatement ps, int[] exprIndex, char value) Sets a value into datastoreStatement at position specified by exprIndex.
void	setDouble(org.datanucleus.ExecutionContext ec, PreparedStatement ps, int[] exprIndex, double value) Sets a value into datastoreStatement at position specified by exprIndex.
void	setFloat(org.datanucleus.ExecutionContext ec, PreparedStatement ps, int[] exprIndex, float value) Sets a value into datastoreStatement at position specified by exprIndex.
void	setInt(org.datanucleus.ExecutionContext ec, PreparedStatement ps, int[] exprIndex, int value) Sets a value into datastoreStatement at position specified by exprIndex.
void	setLong(org.datanucleus.ExecutionContext ec, PreparedStatement ps, int[] exprIndex, long value) Sets a value into datastoreStatement at position specified by exprIndex.
void	setMemberMetaData(org.datanucleus.metadata.AbstractMemberMetaData mmd) Method to set the metadata of the member for which this mapping applies.
void	setObject(org.datanucleus.ExecutionContext ec, PreparedStatement ps, int[] exprIndex, Object value) Sets a value into datastoreStatement at position specified by exprIndex.
void	setObject(org.datanucleus.ExecutionContext ec, PreparedStatement ps, int[] exprIndex, Object value, org.datanucleus.state.ObjectProvider ownerOP, int ownerFieldNumber) Sets a value into datastoreStatement at position specified by exprIndex.
void	setReferenceMapping(JavaTypeMapping referenceMapping) Method to set the mapping at the other end of the relation.
void	setRoleForMember(org.datanucleus.metadata.FieldRole role) Method to set the role for the field/property.
void	setShort(org.datanucleus.ExecutionContext ec, PreparedStatement ps, int[] exprIndex, short value) Sets a value into datastoreStatement at position specified by exprIndex.
void	setString(org.datanucleus.ExecutionContext ec, PreparedStatement ps, int[] exprIndex, String value) Sets a value into datastoreStatement at position specified by exprIndex.
void	setTable(Table table)

Methods inherited from class java.lang.Object

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

Field Detail

mmd

protected org.datanucleus.metadata.AbstractMemberMetaData mmd

MetaData for the field/property that we are mapping. Null when it applies to a query parameter.

roleForMember

protected org.datanucleus.metadata.FieldRole roleForMember

Role of the mapping for the field. Whether it is for the field as a whole, or element of a collection field (in a join table), or key/value of a map field (in a join table).

columnMappings

protected ColumnMapping[] columnMappings

The Column mappings for this Java type.

table

protected Table table

The Table storing this mapping. Null when it applies to a query parameter.

storeMgr

protected RDBMSStoreManager storeMgr

StoreManager for the datastore being used.

type

protected String type

Actual type being mapped

referenceMapping

protected JavaTypeMapping referenceMapping

Mapping of the reference on the end of a bidirectional association. Only used when this mapping doesn't have columns, but the other side has.

absFieldNumber

protected int absFieldNumber

Absolute field number for this mapping. Will match "mmd" unless this is an embedded field.

Constructor Detail

JavaTypeMapping

protected JavaTypeMapping()

Create a new empty JavaTypeMapping. The caller must call one of the initialize() methods to initialise the instance with the DatastoreAdapter and its type. The combination of this empty constructor and one of the initialize() methods is used instead of parameterised constructors for efficiency purpose, both in execution time and code maintainability. See MappingFactory for how they are used. Concrete subclasses must have a publicly accessible empty constructor.

Method Detail

initialize

public void initialize(RDBMSStoreManager storeMgr,
                       String type)

Initialise this JavaTypeMapping with the given StoreManager for the given type. Used when the mapping is for a parameter in a query. This will not set the "mmd" and "datastoreContainer" parameters. If these are required for usage of the mapping then you should call "setFieldInformation(AbstractMemberMetaData, DatastoreContainerObject)" below Subclasses should override this method to perform any datastore initialization operations.

Parameters:

storeMgr - The Datastore Adapter that this Mapping should use.

type - The Class that this mapping maps to the database.

initialize

public void initialize(org.datanucleus.metadata.AbstractMemberMetaData mmd,
                       Table table,
                       org.datanucleus.ClassLoaderResolver clr)

Initialize this JavaTypeMapping for the supplied table and field/property metadata. Subclasses should override this method to perform any datastore initialization operations. Assumes the "roleForMember" is already set

Parameters:

mmd - MetaData for the field/property to be mapped (if any)

table - The table storing this mapping (if any)

clr - the ClassLoaderResolver

hashCode

public int hashCode()

Hash code function.

Overrides:

hashCode in class Object

Returns:

The hash code for this object

equals

public boolean equals(Object obj)

Equality operator.

Overrides:

equals in class Object

Parameters:

obj - Object to compare against

Returns:

Whether they are equal

setMemberMetaData

public void setMemberMetaData(org.datanucleus.metadata.AbstractMemberMetaData mmd)

Method to set the metadata of the member for which this mapping applies. For use where the mapping was created for a particular type (using the initialize(StoreManager, String) and we now have the member that it applies for.

Parameters:

mmd - Field/Property MetaData

getMemberMetaData

public org.datanucleus.metadata.AbstractMemberMetaData getMemberMetaData()

Accessor for the MetaData of the field/property being mapped. Will be null if this mapping is for a literal in a query.

Returns:

Returns the metadata for the field or property

getStoreManager

public RDBMSStoreManager getStoreManager()

setTable

public void setTable(Table table)

getTable

public Table getTable()

Accessor for the table. Will be null if this mapping is for a literal in a query.

Returns:

The datastore class containing this mapped field.

getRoleForMember

public org.datanucleus.metadata.FieldRole getRoleForMember()

Accessor for the role of this mapping for the field/property.

Returns:

Role of this mapping for the field/property

setRoleForMember

public void setRoleForMember(org.datanucleus.metadata.FieldRole role)

Method to set the role for the field/property. Should be called before initialize().

Parameters:

role - Role for field/property.

getAbsoluteFieldNumber

protected int getAbsoluteFieldNumber()

setAbsFieldNumber

public void setAbsFieldNumber(int num)

isSerialised

public boolean isSerialised()

Convenience method to return if the (part of the) field being represented by this mapping is serialised.

Returns:

Whether to use Java serialisation

isNullable

public boolean isNullable()

Accessor for whether this mapping is nullable

Returns:

Whether it is nullable

hasSimpleDatastoreRepresentation

public boolean hasSimpleDatastoreRepresentation()

Whether the mapping has a simple (single column) datastore representation.

Returns:

Whether it has a simple datastore representation (single column)

representableAsStringLiteralInStatement

public boolean representableAsStringLiteralInStatement()

The vast majority of types can be added to a (SQL) statement in their String form and the statement would operate ok. Some types (e.g spatial types) cannot be used in their String form in a statement, so have to be represented as parameters to the statement.

Returns:

Whether a literal of this type can be considered in its String form (otherwise has to be a parameter).

getColumnMappings

public ColumnMapping[] getColumnMappings()

Accessor for the column mappings for this java type

Returns:

The column mapping(s)

getColumnMapping

public ColumnMapping getColumnMapping(int index)

Accessor for a column mapping

Parameters:

index - The id of the column

Returns:

The column mapping

addColumnMapping

public void addColumnMapping(ColumnMapping cm)

Method to add a column mapping

Parameters:

cm - The column mapping

getNumberOfColumnMappings

public int getNumberOfColumnMappings()

Accessor for the number of column mappings.

Returns:

the number of column mappings

getValueForColumnMapping

public Object getValueForColumnMapping(org.datanucleus.NucleusContext nucleusCtx,
                                       int index,
                                       Object value)

Method to return the value to be stored in the specified column index given the overall value for this java type. All multi-column mappings must override this.

Parameters:

nucleusCtx - Context

index - The datastore index

value - The overall value for this java type

Returns:

The value for this datastore index

getReferenceMapping

public JavaTypeMapping getReferenceMapping()

Accessor for the mapping at the other end of a relation when this field is part of a 1-1, 1-N, M-N (bidirectional) relation. Will be null otherwise.

Returns:

The mapping at the other end.

setReferenceMapping

public void setReferenceMapping(JavaTypeMapping referenceMapping)

Method to set the mapping at the other end of the relation. Only used when part of a (bidirectional) relation.

Parameters:

referenceMapping - The mapping at the other end

getJavaType

public abstract Class getJavaType()

Accessor for the java type being mapped. This is the java type that the mapping represents. Some examples :

• if the field is of type "MyClass" then the mapping will be OIDMapping (or subclass) the javaType will be OID, and the type will be MyClass.
• if the field is of type "int" then the mapping will be IntegerMapping, the javaType will be Integer, and the type will be int.

The "java type" is the java-type name used in the plugin.xml mapping file

Returns:

The java type

getJavaTypeForColumnMapping

public String getJavaTypeForColumnMapping(int index)

Accessor for the name of the java-type actually used when mapping the particular column. This java-type must have an entry in the column mappings. The default implementation throws an UnsupportedOperationException.

Parameters:

index - requested column index.

Returns:

the name of java-type for the requested column.

getType

public String getType()

Accessor for the class name of the object that is being mapped here. There are mainly two situations:

• For a JavaTypeMapping that maps a persistable class field, this will return the type of the field. For example with a field of type "MyClass" this will return "MyClass"
• For a JavaTypeMapping that maps a variable or parameter in a query, this will return the type declared in the query.

Returns:

The actual type that this Mapping maps.

includeInFetchStatement

public boolean includeInFetchStatement()

Accessor for whether this mapping is to be included in any fetch statement.

Returns:

Whether to include this mapping in a fetch statement

includeInUpdateStatement

public boolean includeInUpdateStatement()

Accessor for whether this mapping is to be included in the update statement.

Returns:

Whether to include in update statement

includeInInsertStatement

public boolean includeInInsertStatement()

Accessor for whether this mapping is to be included in the insert statement.

Returns:

Whether to include in insert statement

failureMessage

protected String failureMessage(String method)

Utility to output any error message.

Parameters:

method - The method that failed.

Returns:

the localised failure message

setBoolean

public void setBoolean(org.datanucleus.ExecutionContext ec,
                       PreparedStatement ps,
                       int[] exprIndex,
                       boolean value)

Sets a value into datastoreStatement at position specified by exprIndex.

Parameters:

ec - ExecutionContext

ps - PreparedStatement

exprIndex - the position of the value in the statement

value - the value

getBoolean

public boolean getBoolean(org.datanucleus.ExecutionContext ec,
                          ResultSet rs,
                          int[] exprIndex)

Obtains a value from datastoreResults at position specified by exprIndex.

Parameters:

ec - ExecutionContext

rs - ResultSet

exprIndex - the position of the value in the result

Returns:

the value

setChar

public void setChar(org.datanucleus.ExecutionContext ec,
                    PreparedStatement ps,
                    int[] exprIndex,
                    char value)

Sets a value into datastoreStatement at position specified by exprIndex.

Parameters:

ec - ExecutionContext

ps - PreparedStatement

exprIndex - the position of the value in the statement

value - the value

getChar

public char getChar(org.datanucleus.ExecutionContext ec,
                    ResultSet rs,
                    int[] exprIndex)

Obtains a value from datastoreResults at position specified by exprIndex.

Parameters:

ec - ExecutionContext

rs - ResultSet

exprIndex - the position of the value in the result

Returns:

the value

setByte

public void setByte(org.datanucleus.ExecutionContext ec,
                    PreparedStatement ps,
                    int[] exprIndex,
                    byte value)

Sets a value into datastoreStatement at position specified by exprIndex.

Parameters:

ec - ExecutionContext

ps - PreparedStatement

exprIndex - the position of the value in the statement

value - the value

getByte

public byte getByte(org.datanucleus.ExecutionContext ec,
                    ResultSet rs,
                    int[] exprIndex)

Obtains a value from datastoreResults at position specified by exprIndex.

Parameters:

ec - ExecutionContext

rs - ResultSet

exprIndex - the position of the value in the result

Returns:

the value

setShort

public void setShort(org.datanucleus.ExecutionContext ec,
                     PreparedStatement ps,
                     int[] exprIndex,
                     short value)

Sets a value into datastoreStatement at position specified by exprIndex.

Parameters:

ec - execution context

ps - PreparedStatement

exprIndex - the position of the value in the statement

value - the value

getShort

public short getShort(org.datanucleus.ExecutionContext ec,
                      ResultSet rs,
                      int[] exprIndex)

Obtains a value from datastoreResults at position specified by exprIndex.

Parameters:

ec - ExecutionContext

rs - ResultSet

exprIndex - the position of the value in the result

Returns:

the value

setInt

public void setInt(org.datanucleus.ExecutionContext ec,
                   PreparedStatement ps,
                   int[] exprIndex,
                   int value)

Sets a value into datastoreStatement at position specified by exprIndex.

Parameters:

ec - ExecutionContext

ps - PreparedStatement

exprIndex - the position of the value in the statement

value - the value

getInt

public int getInt(org.datanucleus.ExecutionContext ec,
                  ResultSet rs,
                  int[] exprIndex)

Obtains a value from datastoreResults at position specified by exprIndex.

Parameters:

ec - ExecutionContext

rs - ResultSet

exprIndex - the position of the value in the result

Returns:

the value

setLong

public void setLong(org.datanucleus.ExecutionContext ec,
                    PreparedStatement ps,
                    int[] exprIndex,
                    long value)

Sets a value into datastoreStatement at position specified by exprIndex.

Parameters:

ec - ExecutionContext

ps - PreparedStatement

exprIndex - the position of the value in the statement

value - the value

getLong

public long getLong(org.datanucleus.ExecutionContext ec,
                    ResultSet rs,
                    int[] exprIndex)

Obtains a value from datastoreResults at position specified by exprIndex.

Parameters:

ec - ExecutionContext

rs - ResultSet

exprIndex - the position of the value in the result

Returns:

the value

setFloat

public void setFloat(org.datanucleus.ExecutionContext ec,
                     PreparedStatement ps,
                     int[] exprIndex,
                     float value)

Sets a value into datastoreStatement at position specified by exprIndex.

Parameters:

ec - ExecutionContext

ps - PreparedStatement

exprIndex - the position of the value in the statement

value - the value

getFloat

public float getFloat(org.datanucleus.ExecutionContext ec,
                      ResultSet rs,
                      int[] exprIndex)

Obtains a value from datastoreResults at position specified by exprIndex.

Parameters:

ec - ExecutionContext

rs - ResultSet

exprIndex - the position of the value in the result

Returns:

the value

setDouble

public void setDouble(org.datanucleus.ExecutionContext ec,
                      PreparedStatement ps,
                      int[] exprIndex,
                      double value)

Sets a value into datastoreStatement at position specified by exprIndex.

Parameters:

ec - ExecutionContext

ps - PreparedStatement

exprIndex - the position of the value in the statement

value - the value

getDouble

public double getDouble(org.datanucleus.ExecutionContext ec,
                        ResultSet rs,
                        int[] exprIndex)

Obtains a value from datastoreResults at position specified by exprIndex.

Parameters:

ec - ExecutionContext

rs - ResultSet

exprIndex - the position of the value in the result

Returns:

the value

setString

public void setString(org.datanucleus.ExecutionContext ec,
                      PreparedStatement ps,
                      int[] exprIndex,
                      String value)

Sets a value into datastoreStatement at position specified by exprIndex.

Parameters:

ec - ExecutionContext

ps - PreparedStatement

exprIndex - the position of the value in the statement

value - the value

getString

public String getString(org.datanucleus.ExecutionContext ec,
                        ResultSet rs,
                        int[] exprIndex)

Obtains a value from datastoreResults at position specified by exprIndex.

Parameters:

ec - ExecutionContext

rs - ResultSet

exprIndex - the position of the value in the result

Returns:

the value

setObject

public void setObject(org.datanucleus.ExecutionContext ec,
                      PreparedStatement ps,
                      int[] exprIndex,
                      Object value,
                      org.datanucleus.state.ObjectProvider ownerOP,
                      int ownerFieldNumber)

Sets a value into datastoreStatement at position specified by exprIndex.

Parameters:

ec - ExecutionContext

ps - PreparedStatement

exprIndex - the position of the value in the statement

value - the value

ownerOP - the owner ObjectProvider

ownerFieldNumber - the owner absolute field number

setObject

public void setObject(org.datanucleus.ExecutionContext ec,
                      PreparedStatement ps,
                      int[] exprIndex,
                      Object value)

Sets a value into datastoreStatement at position specified by exprIndex.

Parameters:

ec - ExecutionContext

ps - PreparedStatement

exprIndex - the position of the value in the statement

value - the value

getObject

public Object getObject(org.datanucleus.ExecutionContext ec,
                        ResultSet rs,
                        int[] exprIndex,
                        org.datanucleus.state.ObjectProvider ownerOP,
                        int ownerFieldNumber)

Obtains a value from datastoreResults at position specified by exprIndex.

Parameters:

ec - ExecutionContext

rs - an object returned from the datastore with values

exprIndex - the position of the value in the result

ownerOP - the owner ObjectProvider

ownerFieldNumber - the owner absolute field number

Returns:

the value

getObject

public Object getObject(org.datanucleus.ExecutionContext ec,
                        ResultSet rs,
                        int[] exprIndex)

Obtains a value from datastoreResults at position specified by exprIndex.

Parameters:

ec - ExecutionContext

rs - ResultSet

exprIndex - the position of the value in the result

Returns:

the value

getColumnMetaDataForMember

protected static org.datanucleus.metadata.ColumnMetaData[] getColumnMetaDataForMember(org.datanucleus.metadata.AbstractMemberMetaData mmd,
                                                                                      org.datanucleus.metadata.FieldRole role)

Convenience method to return the ColumnMetaData appropriate for this mapping. If the mapping is in a join table then picks the correct component for the column definition.

Parameters:

mmd - Metadata for the member

role - The role this mapping plays for the specified member

Returns:

The column metadata (if any)