org.apache.openjpa.jdbc.kernel.exps
Class Null
java.lang.Object
org.apache.openjpa.jdbc.kernel.exps.AbstractVal
org.apache.openjpa.jdbc.kernel.exps.Const
org.apache.openjpa.jdbc.kernel.exps.Null
- All Implemented Interfaces:
- Serializable, Val, Constant, Value
public class Null
- extends Const
A literal null value in a filter.
- Author:
- Abe White
- See Also:
- Serialized Form
| Fields inherited from interface org.apache.openjpa.jdbc.kernel.exps.Val |
ABS_VAL, ARGS_VAL, CMP_EQUAL, COALESCE_VAL, CONCAT_VAL, FORCE_OUTER, GENERALCASE_VAL, INDEXOF_VAL, JOIN_REL, LENGTH_VAL, LOCATE_VAL, LOWER_VAL, MATH_VAL, NULL_CMP, NULLIF_VAL, SIMPLECASE_VAL, SQRT_VAL, SUBSTRING_VAL, TRIM_VAL, UPPER_VAL, VAL, WHENCONDITION_VAL, WHENSCALAR_VAL |
|
Constructor Summary |
Null()
|
|
Method Summary |
void |
appendTo(Select sel,
ExpContext ctx,
ExpState state,
SQLBuffer sql,
int index)
Append the indexth SQL element to the given buffer. |
void |
calculateValue(Select sel,
ExpContext ctx,
ExpState state,
Val other,
ExpState otherState)
Calculate and cache the SQL for this value. |
Class |
getType()
Return the expected type for this value, or Object if
the type is unknown. |
Object |
getValue(Object[] params)
Return the value for this constant given the specified parameters. |
void |
setImplicitType(Class type)
Set the implicit type of the value, based on how it is used in the
filter. |
| Methods inherited from class org.apache.openjpa.jdbc.kernel.exps.Const |
appendIsEmpty, appendIsNotEmpty, appendIsNotNull, appendIsNull, appendSize, getMetaData, getSQLValue, getValue, groupBy, initialize, isSQLValueNull, length, load, orderBy, select, selectColumns, setMetaData |
| Methods inherited from class org.apache.openjpa.jdbc.kernel.exps.AbstractVal |
acceptVisit, appendIndex, appendType, getAlias, getId, getName, getPath, getSelectAs, isAggregate, isVariable, isXPath, setAlias, toDataStoreValue |
| Methods inherited from class java.lang.Object |
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait |
Null
public Null()
getType
public Class getType()
- Description copied from interface:
Value
- Return the expected type for this value, or
Object if
the type is unknown.
setImplicitType
public void setImplicitType(Class type)
- Description copied from interface:
Value
- Set the implicit type of the value, based on how it is used in the
filter. This method is only called on values who return
Object from Value.getType().
getValue
public Object getValue(Object[] params)
- Description copied from interface:
Constant
- Return the value for this constant given the specified parameters.
calculateValue
public void calculateValue(Select sel,
ExpContext ctx,
ExpState state,
Val other,
ExpState otherState)
- Description copied from interface:
Val
- Calculate and cache the SQL for this value. This method is called
before
length or any append methods.
- Specified by:
calculateValue in interface Val- Overrides:
calculateValue in class Const
other - the value being compared to, or null if not a comparison
appendTo
public void appendTo(Select sel,
ExpContext ctx,
ExpState state,
SQLBuffer sql,
int index)
- Description copied from interface:
Val
- Append the
indexth SQL element to the given buffer.
Copyright © 2006-2013 Apache Software Foundation. All Rights Reserved.