org.apache.empire.db.expr.column

Class DBValueExpr

java.lang.Object

org.apache.empire.db.DBObject

org.apache.empire.db.DBExpr

org.apache.empire.db.DBColumnExpr

org.apache.empire.db.expr.column.DBValueExpr

All Implemented Interfaces:

Serializable, ColumnExpr

public class DBValueExpr
extends DBColumnExpr

This class is used for declaring constant values in SQL.

There is no need to explicitly create instances of this class.
Instead use DBDatabase.getValueExpr(String) or one of it's overloads

See Also:

Serialized Form

Field Summary

Fields

Modifier and Type	Field and Description
DBColumnExpr	column
DBDatabase	db
DataType	type
protected Object	value

Fields inherited from class org.apache.empire.db.DBColumnExpr

attributes, beanPropertyName, DBCOLATTR_TITLE, DBCOLATTR_TYPE, options

Fields inherited from class org.apache.empire.db.DBExpr

CTX_ALIAS, CTX_ALL, CTX_DEFAULT, CTX_FULLNAME, CTX_NAME, CTX_NOPARENTHESES, CTX_VALUE

Constructor Summary

Constructors

Constructor and Description
DBValueExpr(DBColumnExpr col, Object value) Construct a new DBValueExpr object set the specified parameters to this object.
DBValueExpr(DBDatabase db, Object value, DataType type) Constructs a new DBValueExpr object.

Method Summary

Modifier and Type	Method and Description
void	addReferencedColumns(Set<DBColumn> list) Internal function to obtain all DBColumnExpr-objects used by this expression.
void	addSQL(StringBuilder buf, long context) Creates the SQL-Command.
Element	addXml(Element parent, long flags) this helper function calls the DBColumnExpr.addXML(Element, long) method
DBDatabase	getDatabase() Returns the current DBDatabase object.
DataType	getDataType() Returns the data type of the DBColumnExpr object.
String	getName() Returns the column name.
DBColumn	getUpdateColumn() Returns null.
Object	getValue() return the value associated with this value expression
boolean	isAggregate() Always returns false since value expressions cannot be an aggregate.
void	setValue(Object value) set the value associated with this value expression

Methods inherited from class org.apache.empire.db.DBColumnExpr

abs, append, as, as, asc, avg, ceiling, cmp, coalesce, convertTo, convertTo, count, countDistinct, day, decode, decode, decode, decode, decode, decode, decodeEnum, decodeSort, desc, divideBy, floor, format, getAttribute, getBeanPropertyName, getControlType, getExprFromPhrase, getExprFromPhrase, getOptions, getSourceColumn, getTitle, in, in, in, indexOf, indexOf, indexOf, is, isBetween, isGreaterThan, isLessOrEqual, isMoreOrEqual, isNot, isNotBetween, isSmallerThan, length, like, like, likeLower, likeUpper, lower, max, min, minus, minus, modulo, month, multiplyWith, notIn, notIn, notIn, notLike, nvl, parenthesis, plus, plus, replace, reverse, round, setAttribute, setBeanPropertyName, setControlType, setOptions, setTitle, substring, substring, substring, substring, substring, substring, sum, toChar, toChar, trim, trimLeft, trimRight, trunc, upper, when, year

Methods inherited from class org.apache.empire.db.DBExpr

getObjectValue, getValueClass

Methods inherited from class java.lang.Object

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

Field Detail

db

public final DBDatabase db

type

public final DataType type

column

public final DBColumnExpr column

value

protected Object value

Constructor Detail

DBValueExpr

public DBValueExpr(DBDatabase db,
                   Object value,
                   DataType type)

Constructs a new DBValueExpr object.

Parameters:

db - the database

value - the value for this constant

type - the data type for this constant

DBValueExpr

public DBValueExpr(DBColumnExpr col,
                   Object value)

Construct a new DBValueExpr object set the specified parameters to this object.

Parameters:

col - the column

value - the value

Method Detail

getValue

public Object getValue()

return the value associated with this value expression

Returns:

the current value

setValue

public void setValue(Object value)

set the value associated with this value expression

Parameters:

the - value

getDatabase

public DBDatabase getDatabase()

Returns the current DBDatabase object.

Specified by:

getDatabase in class DBObject

Returns:

the current DBDatabase object

getDataType

public DataType getDataType()

Returns the data type of the DBColumnExpr object.

Specified by:

getDataType in interface ColumnExpr

Specified by:

getDataType in class DBColumnExpr

Returns:

the data type

See Also:

DataType

getName

public String getName()

Returns the column name.

Specified by:

getName in interface ColumnExpr

Specified by:

getName in class DBColumnExpr

Returns:

the column name

addXml

public Element addXml(Element parent,
                      long flags)

this helper function calls the DBColumnExpr.addXML(Element, long) method

Specified by:

addXml in class DBColumnExpr

Parameters:

parent - the parent element to which to append the column description

flags - currently not used

Returns:

the newly created child element

getUpdateColumn

public DBColumn getUpdateColumn()

Returns null.

Specified by:

getUpdateColumn in class DBColumnExpr

Returns:

null

isAggregate

public boolean isAggregate()

Always returns false since value expressions cannot be an aggregate.

Specified by:

isAggregate in class DBColumnExpr

Returns:

false

addSQL

public void addSQL(StringBuilder buf,
                   long context)

Creates the SQL-Command.

Specified by:

addSQL in class DBExpr

Parameters:

buf - the SQL-Command

context - the current SQL-Command context

addReferencedColumns

public void addReferencedColumns(Set<DBColumn> list)

Description copied from class: DBExpr

Internal function to obtain all DBColumnExpr-objects used by this expression.

Specified by:

addReferencedColumns in class DBExpr

Parameters:

list - list to which all used column expressions must be added

See Also:

DBExpr.addReferencedColumns(Set)