Package 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:

ColumnExpr, DBPreparable

public class DBValueExpr
extends DBColumnExpr
implements DBPreparable

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

Field Summary

Fields

Modifier and Type	Field	Description
final DBDatabase	db
static String	IGNORE_CASE_CONTEXT
final DataType	type
protected Object	value

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

attributes, beanPropertyName, options

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

CTX_ALIAS, CTX_ALL, CTX_DEFAULT, CTX_FULLNAME, CTX_NAME, CTX_NOPARENTHESIS, CTX_VALUE

Constructor Summary

Constructors

Constructor	Description
DBValueExpr(DBDatabase db, Object value, DataType type)	Deprecated. please use DBDatabase.getValueExpr(...)

Method Summary

Modifier and Type	Method	Description
void	addReferencedColumns(Set<DBColumn> list)	Internal function to obtain all DBColumnExpr-objects used by this expression.
void	addSQL(DBSQLBuilder sql, long context)	Creates the SQL-Command.
Element	addXml(Element parent, long flags)	this helper function calls the DBColumnExpr.addXML(Element, long) method
DBValueExpr	autoParam()	Sets literal mode off, i.e. the value may passed as a parameter and referenced by a ?
boolean	equals(Object other)	Returns true if other is equal to this expression
final DBDatabase	getDatabase()	Returns the current DBDatabase object.
DataType	getDataType()	Returns the data type of the DBColumnExpr object.
Class<Enum<?>>	getEnumType()	Returns the EnumType if the value is an Enum
DBColumnExpr	getIgnoreCaseExpr(DBColumnExpr context)	Returns an expression which ignores the case Only for case sensitive columns!
String	getName()	Returns the column name.
DBRowSet	getRowSet()	Returns null.
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.
DBValueExpr	literal()	Set literal mode, i.e. the value will be placed in the sql statement Otherwise it may be automatically replaced by a parameter ?
void	prepareParams(DBCommand cmd, DBExpr parent)	Prepares an expression for a query This function is called by DBCommand in order to add values as query parameters instead of being literally included in the sql statement Please Note: This function is internally called.
void	setValue(Object value)	set the value associated with this value expression

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

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

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

checkParamNull

Methods inherited from class java.lang.Object

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

Field Details

IGNORE_CASE_CONTEXT

public static String IGNORE_CASE_CONTEXT

db

public final DBDatabase db

type

public final DataType type

value

protected Object value

Constructor Details

DBValueExpr

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

Deprecated.

please use DBDatabase.getValueExpr(...) The constructor will be made protected in future versions

Constructs a new DBValueExpr object.

Parameters:

db - the database

value - the value for this constant

type - the data type for this constant

Method Details

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:

value - the value to set

getDatabase

public final 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

getEnumType

public Class<Enum<?>> getEnumType()

Returns the EnumType if the value is an Enum

Specified by:

getEnumType in interface ColumnExpr

Returns:

the enum type

getName

public String getName()

Returns the column name.

Specified by:

getName in interface ColumnExpr

Specified by:

getName in class DBColumnExpr

Returns:

the column name

getRowSet

public DBRowSet getRowSet()

Returns null.

Specified by:

getRowSet in class DBColumnExpr

Returns:

null

getUpdateColumn

public DBColumn getUpdateColumn()

Returns null.

Specified by:

getUpdateColumn in interface ColumnExpr

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

equals

public boolean equals(Object other)

Returns true if other is equal to this expression

Overrides:

equals in class Object

getIgnoreCaseExpr

public DBColumnExpr getIgnoreCaseExpr(DBColumnExpr context)

Returns an expression which ignores the case Only for case sensitive columns! Default is upper(expr)

Parameters:

context - the column context

Returns:

the ignore case expression or the expression itself

literal

public DBValueExpr literal()

Set literal mode, i.e. the value will be placed in the sql statement Otherwise it may be automatically replaced by a parameter ?

Returns:

self (this)

autoParam

public DBValueExpr autoParam()

Sets literal mode off, i.e. the value may passed as a parameter and referenced by a ? in the sql statement

Returns:

self (this)

prepareParams

public void prepareParams(DBCommand cmd,
 DBExpr parent)

Description copied from interface: DBPreparable

Prepares an expression for a query This function is called by DBCommand in order to add values as query parameters instead of being literally included in the sql statement Please Note: This function is internally called. Do not call yourself!

Specified by:

prepareParams in interface DBPreparable

Parameters:

cmd - the command to which to add the parameters

parent - the parent expression holding the value

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)

addSQL

public void addSQL(DBSQLBuilder sql,
 long context)

Creates the SQL-Command.

Specified by:

addSQL in class DBExpr

Parameters:

sql - the SQL-Command

context - the current SQL-Command context

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