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

Class DBConcatExpr

java.lang.Object

org.apache.empire.db.DBObject

org.apache.empire.db.DBExpr

org.apache.empire.db.DBColumnExpr

org.apache.empire.db.expr.column.DBConcatExpr

All Implemented Interfaces:

ColumnExpr

public class DBConcatExpr
extends DBColumnExpr

This class is used for performing string concatenation in SQL

There is no need to explicitly create instances of this class.
Instead use DBColumnExpr.append(Object)

Field Summary

Fields

Modifier and Type	Field	Description
protected final DBColumnExpr	left
protected final Object	right

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
DBConcatExpr(DBColumnExpr left, Object right)	Constructs a new DBConcatExpr object set the specified parameters to this object.

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 concatenate a specified column with a specified value sets the column with a specified value to the SQL-Command.
Element	addXml(Element parent, long flags)	Add a description of this column with relevant metadata to the supplied parent XML Element.
boolean	equals(Object other)	Returns true if other is equal to this expression
final DBDatabase	getDatabase()	Returns the database object to which this object belongs to.
DataType	getDataType()	Returns the data type: DataType.VARCHAR
Class<Enum<?>>	getEnumType()	Not an Enum.
String	getName()	Returns the column name for this column expression.
DBRowSet	getRowSet()	Returns the underlying rowset
DBColumn	getUpdateColumn()	Returns the underlying column
boolean	isAggregate()	Always returns false since a concat expression cannot be an aggregate.

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

left

protected final DBColumnExpr left

right

protected final Object right

Constructor Details

DBConcatExpr

public DBConcatExpr(DBColumnExpr left,
 Object right)

Constructs a new DBConcatExpr object set the specified parameters to this object.

Parameters:

left - the left column for this concatenation

right - the right column for this concatenation

Method Details

getDatabase

public final DBDatabase getDatabase()

Description copied from class: DBObject

Returns the database object to which this object belongs to. For the database object itself this function will return the this pointer.

Specified by:

getDatabase in class DBObject

Returns:

the database object

getDataType

public DataType getDataType()

Returns the data type: DataType.VARCHAR

Specified by:

getDataType in interface ColumnExpr

Specified by:

getDataType in class DBColumnExpr

Returns:

DataType.VARCHAR

See Also:

• DataType

getEnumType

public Class<Enum<?>> getEnumType()

Not an Enum. Returns null

Returns:

the enum type

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

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 a concat expression 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

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 concatenate a specified column with a specified value sets the column with a specified 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)

Description copied from class: DBColumnExpr

Add a description of this column with relevant metadata to the supplied parent XML Element.

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