org.jpox.store.mapping
Class NullMapping

java.lang.Object
  org.jpox.store.mapping.JavaTypeMapping
      org.jpox.store.mapping.SingleFieldMapping
          org.jpox.store.mapping.NullMapping

public class NullMapping
extends SingleFieldMapping

Simple mapping for a null literal. Only used when the type is not determined

Version:

$Revision: 1.3 $

Field Summary

Fields inherited from class org.jpox.store.mapping.SingleFieldMapping

datastoreContainer, typeInfo

Fields inherited from class org.jpox.store.mapping.JavaTypeMapping

datastoreMappings, dba, fmd, LOCALISER, referenceMapping, type

Constructor Summary

NullMapping(DatastoreAdapter dba)

Method Summary

java.lang.Class	getJavaType() Accessor for the java type being mapped
java.lang.Object	getObject(PersistenceManager pm, java.lang.Object resultSet, int[] exprIndex) Obtains a value from resultSet at position specified by exprIndex.
java.lang.Object	getSampleValue() Return a sample value of the mapping type to be used for internal evaluation of type and conversion.
ScalarExpression	newLiteral(QueryExpression qs, java.lang.Object value) Creates a literal from an value.
ScalarExpression	newScalarExpression(QueryExpression qs, LogicSetExpression te) Creates a expression from a field name/table.
void	setObject(PersistenceManager pm, java.lang.Object preparedStatement, int[] exprIndex, java.lang.Object value) Sets a value into preparedStatement at position specified by exprIndex.

Methods inherited from class org.jpox.store.mapping.SingleFieldMapping

equals, getBoolean, getByte, getChar, getDatastoreContainer, getDouble, getFloat, getInt, getLong, getShort, getString, hasValue, includeInFetchStatement, includeInInsertStatement, includeInUpdateStatement, prepareDatastoreMapping, setBoolean, setByte, setChar, setDouble, setFloat, setInt, setLong, setShort, setString

Methods inherited from class org.jpox.store.mapping.JavaTypeMapping

addDataStoreMapping, failureMessage, getDataStoreMapping, getDataStoreMappings, getFieldMetaData, getNumberOfDatastoreFields, getObject, getReferenceMapping, getType, isNullable, setDefault, setObject, setReferenceMapping

Methods inherited from class java.lang.Object

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

Constructor Detail

NullMapping

public NullMapping(DatastoreAdapter dba)

Method Detail

getJavaType

public java.lang.Class getJavaType()

Description copied from class: JavaTypeMapping

Accessor for the java type being mapped

Specified by:

getJavaType in class JavaTypeMapping

Returns:

The java type

getSampleValue

public java.lang.Object getSampleValue()

Description copied from class: JavaTypeMapping

Return a sample value of the mapping type to be used for internal evaluation of type and conversion.

Specified by:

getSampleValue in class JavaTypeMapping

Returns:

The sample value.

getObject

public java.lang.Object getObject(PersistenceManager pm,
                                  java.lang.Object resultSet,
                                  int[] exprIndex)

Description copied from class: JavaTypeMapping

Obtains a value from resultSet at position specified by exprIndex.

Overrides:

getObject in class SingleFieldMapping

Parameters:

pm - the PersistenceManager

resultSet - an object returned from the datastore with values

exprIndex - the position of the value in the result

Returns:

the value

setObject

public void setObject(PersistenceManager pm,
                      java.lang.Object preparedStatement,
                      int[] exprIndex,
                      java.lang.Object value)

Description copied from class: JavaTypeMapping

Sets a value into preparedStatement at position specified by exprIndex.

Overrides:

setObject in class SingleFieldMapping

Parameters:

pm - the PersistenceManager

preparedStatement - a datastore object that executes statements in the database

exprIndex - the position of the value in the statement

value - the value

newLiteral

public ScalarExpression newLiteral(QueryExpression qs,
                                   java.lang.Object value)

Description copied from class: JavaTypeMapping

Creates a literal from an value. A string literal is enclosed in single quotes. for example: "literal". A string literal that includes a single quote is represented by two single quotes. for example: "literal''s". An exact numeric literal is a numeric value without a decimal point, such as 57, -957, +62. An approximate numeric literal is a numeric value in scientific notation, such as 7E3, -57.9E2, or a numeric value with a decimal, such as 7., -95.7, +6.2.

Specified by:

newLiteral in class JavaTypeMapping

Parameters:

qs - The Query statement

value - The object

Returns:

A Scalar Expression

newScalarExpression

public ScalarExpression newScalarExpression(QueryExpression qs,
                                            LogicSetExpression te)

Description copied from class: JavaTypeMapping

Creates a expression from a field name/table. e.g. tablename.fieldname; tablealias.fieldalias

Specified by:

newScalarExpression in class JavaTypeMapping

Parameters:

qs - The Query statement

te - the alias for the table

Returns:

A Scalar Expression