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

Class DBCaseWhenExpr

java.lang.Object

org.apache.empire.db.DBObject

org.apache.empire.db.DBExpr

org.apache.empire.db.DBColumnExpr

org.apache.empire.db.expr.column.DBCaseExpr

org.apache.empire.db.expr.column.DBCaseWhenExpr

All Implemented Interfaces:

ColumnExpr

public class DBCaseWhenExpr
extends DBCaseExpr

This class is used to create a SQL CASE constraint in the form of case when {cond1} then {result1} when {cond2} then {result2} ... else {defaultResult} end" There is no need to explicitly create instances of this class.

Author:

doebele

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
DBCaseWhenExpr(DBDatabase db, Map<DBCompareExpr,? extends Object> whenMap, Object elseValue)	Constructs a DBCaseExpr
DBCaseWhenExpr(DBCompareExpr cmpExpr, Object trueExpr, Object elseValue)

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)	Used to build the SQL command.
boolean	equals(Object other)	Returns true if other is equal to this expression
String	getName()	Returns the column name for this column expression.

Methods inherited from class org.apache.empire.db.expr.column.DBCaseExpr

addXml, getDatabase, getDataType, getEnumType, getRowSet, getSourceColumnExpr, getUpdateColumn, init, initDataTypeFromValue, isAggregate, isNotNull, isNull

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

Constructor Details

DBCaseWhenExpr

public DBCaseWhenExpr(DBDatabase db,
 Map<DBCompareExpr,? extends Object> whenMap,
 Object elseValue)

Constructs a DBCaseExpr

Parameters:

db - the database

whenMap - a map of compareExpressions with the corresponding result values

elseValue - the expression returned if no condition is true (may be null)

DBCaseWhenExpr

public DBCaseWhenExpr(DBCompareExpr cmpExpr,
 Object trueExpr,
 Object elseValue)

Method Details

getName

public String getName()

Description copied from class: DBColumnExpr

Returns the column name for this column expression. The name must contain only alphanumeric characters and the underscore. For SQL functions this name may be generated. However subsequent calls to this function for the same object instance must return the same string.

Specified by:

getName in interface ColumnExpr

Specified by:

getName in class DBColumnExpr

Returns:

the column name

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

addSQL

public void addSQL(DBSQLBuilder sql,
 long context)

Description copied from class: DBExpr

Used to build the SQL command. SQL for this expression must be appended to StringBuilder.

Specified by:

addSQL in class DBExpr

Parameters:

sql - the string buffer used to build the sql command

context - context flag for this SQL-Command (see CTX_??? constants).