Package org.apache.empire.db.expr.column

Class DBCalcExpr

java.lang.Object

org.apache.empire.db.DBObject

org.apache.empire.db.DBExpr

org.apache.empire.db.DBColumnExpr

org.apache.empire.db.expr.column.DBCalcExpr

All Implemented Interfaces:

ColumnExpr

public class DBCalcExpr
extends DBColumnExpr

This class is used for performing calculations in SQL
It handles the mathematical operations ("+", "-", "*", "/") for the current column.

There is no need to explicitly create instances of this class.
Instead use DBColumnExpr.plus(Object), DBColumnExpr.minus(Object), DBColumnExpr.multiplyWith(Object), DBColumnExpr.divideBy(Object)

Field Summary

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
DBCalcExpr(DBColumnExpr expr, String op, Object value)	Constructs a DBCalcExpr object Sets the mathematical operations ("+", "-", "*", "/") for the specified DBColumnExpr object and value.

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 adds the mathematical operations for the specified DBColumnExpr object and value to the.
Element	addXml(Element parent, long flags)	This function set the specified mathematical operations to the XML tag.
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: DBDataType.DECIMAL.
Class<Enum<?>>	getEnumType()	Not an Enum.
String	getName()	Returns the given expression name.
DBRowSet	getRowSet()	Returns the underlying rowset
DBColumn	getUpdateColumn()	Returns the underlying column
boolean	isAggregate()	Always returns false since CalcExpressions cannot be aggregates.
String	toString()	For Debugging

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, 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

Constructor Details

DBCalcExpr

public DBCalcExpr(DBColumnExpr expr,
 String op,
 Object value)

Constructs a DBCalcExpr object Sets the mathematical operations ("+", "-", "*", "/")
for the specified DBColumnExpr object and value.

Parameters:

expr - an DBColumnExpr object, one column

op - the mathematical operation ("+", "-", "*" or "/")

value - the value to multiply, divide, sum or subtract

Method Details

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: DBDataType.DECIMAL.

Specified by:

getDataType in interface ColumnExpr

Specified by:

getDataType in class DBColumnExpr

Returns:

the expressions data type

See Also:

• DataType

getEnumType

public Class<Enum<?>> getEnumType()

Not an Enum. Returns null

Returns:

the enum type

getName

public String getName()

Returns the given expression name.

Specified by:

getName in interface ColumnExpr

Specified by:

getName in class DBColumnExpr

Returns:

the column name

getRowSet

public DBRowSet getRowSet()

Returns the underlying rowset

Specified by:

getRowSet in class DBColumnExpr

Returns:

a column used for this expression

getUpdateColumn

public DBColumn getUpdateColumn()

Returns the underlying column

Specified by:

getUpdateColumn in interface ColumnExpr

Specified by:

getUpdateColumn in class DBColumnExpr

Returns:

the underlying column

isAggregate

public boolean isAggregate()

Always returns false since CalcExpressions cannot be aggregates.

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

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 adds the mathematical operations for the specified DBColumnExpr object and value to the. SQL-Command

Specified by:

addSQL in class DBExpr

Parameters:

sql - the SQL statment

context - the current SQL-Command context

addXml

public Element addXml(Element parent,
 long flags)

This function set the specified mathematical operations to the XML tag.

Specified by:

addXml in class DBColumnExpr

Parameters:

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

flags - currently not used

Returns:

the XML tag (with the mathematical operations)

toString

public String toString()

Description copied from class: DBColumnExpr

For Debugging

Overrides:

toString in class DBColumnExpr