adql.query.constraint

Class IsNull

java.lang.Object

adql.query.constraint.IsNull

All Implemented Interfaces:

ADQLObject, ADQLConstraint

public class IsNull
extends java.lang.Object
implements ADQLConstraint

Represents a comparison between a column to the NULL value.

Version:

1.4 (06/2015)

Author:

Grégory Mantelet (CDS;ARI)

Constructor Summary

Constructors

Constructor and Description
IsNull(ADQLColumn column) Builds a comparison between the given column and NULL.
IsNull(ADQLColumn column, boolean isNot) Builds a comparison between the column and NULL.
IsNull(IsNull toCopy) Builds a IsNull constraint by copying the given one.

Method Summary

Modifier and Type	Method and Description
ADQLIterator	adqlIterator() Gets an iterator on the intern ADQL objects.
ADQLColumn	getColumn() Gets the column whose the value is compared to NULL.
ADQLObject	getCopy() Gets a (deep) copy of this ADQL object.
java.lang.String	getName() Gets the name of this object in ADQL.
TextPosition	getPosition() Gets the position of this object/token in the ADQL query.
boolean	isNotNull() Tells whether the predicate is IS NULL or IS NOT NULL.
void	setColumn(ADQLColumn column) Lets changing the column whose the value must be compared to NULL.
void	setNotNull(boolean notNull) Lets indicating which predicate must be used (IS NULL or IS NOT NULL).
void	setPosition(TextPosition position) Set the position of this IsNull in the given ADQL query string.
java.lang.String	toADQL() Gets the ADQL expression of this object.

Methods inherited from class java.lang.Object

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

Constructor Detail

IsNull

public IsNull(ADQLColumn column)
       throws java.lang.NullPointerException

Builds a comparison between the given column and NULL.

Parameters:

column - The column whose the value must be compared to NULL.

Throws:

java.lang.NullPointerException - If the given column is null.

IsNull

public IsNull(ADQLColumn column,
              boolean isNot)
       throws java.lang.NullPointerException

Builds a comparison between the column and NULL.

Parameters:

column - The column whose the value must be compared to NULL.

isNot - true means IS NOT NULL, false means IS NULL.

Throws:

java.lang.NullPointerException - If the given column is null.

IsNull

public IsNull(IsNull toCopy)
       throws java.lang.Exception

Builds a IsNull constraint by copying the given one.

Parameters:

toCopy - The IsNull to copy.

Throws:

java.lang.Exception - If there is an error during the copy.

Method Detail

getColumn

public final ADQLColumn getColumn()

Gets the column whose the value is compared to NULL.

Returns:

The column compared to NULL.

setColumn

public final void setColumn(ADQLColumn column)
                     throws java.lang.NullPointerException

Lets changing the column whose the value must be compared to NULL.

Parameters:

column - The new column to compare to NULL.

Throws:

java.lang.NullPointerException - If the given column is null.

isNotNull

public final boolean isNotNull()

Tells whether the predicate is IS NULL or IS NOT NULL.

Returns:

true for IS NOT NULL, false for IS NULL.

setNotNull

public final void setNotNull(boolean notNull)

Lets indicating which predicate must be used (IS NULL or IS NOT NULL).

Parameters:

notNull - true for IS NOT NULL, false for IS NULL.

getPosition

public final TextPosition getPosition()

Description copied from interface: ADQLObject

Gets the position of this object/token in the ADQL query.

By default, no position should be set.

Specified by:

getPosition in interface ADQLObject

Returns:

Position of this ADQL item in the ADQL query, or NULL if not written originally in the query (for example, if added afterwards.

setPosition

public final void setPosition(TextPosition position)

Set the position of this IsNull in the given ADQL query string.

Parameters:

position - New position of this IsNull.

Since:

1.4

getCopy

public ADQLObject getCopy()
                   throws java.lang.Exception

Description copied from interface: ADQLObject

Gets a (deep) copy of this ADQL object.

Specified by:

getCopy in interface ADQLObject

Returns:

The copy of this ADQL object.

Throws:

java.lang.Exception - If there is any error during the copy.

getName

public java.lang.String getName()

Description copied from interface: ADQLObject

Gets the name of this object in ADQL.

Specified by:

getName in interface ADQLObject

Returns:

The name of this ADQL object.

adqlIterator

public ADQLIterator adqlIterator()

Description copied from interface: ADQLObject

Gets an iterator on the intern ADQL objects.

Note:The returned iterator is particularly used by a ISearchHandler extension to browse a whole ADQL tree.

Specified by:

adqlIterator in interface ADQLObject

Returns:

An ADQL objects iterator.

See Also:

ADQLIterator, ISearchHandler

toADQL

public java.lang.String toADQL()

Description copied from interface: ADQLObject

Gets the ADQL expression of this object.

Specified by:

toADQL in interface ADQLObject

Returns:

The corresponding ADQL expression.