WorkHorseForCollatorDatatypes (Apache Derby V10.14 Internals)

java.lang.Object
- org.apache.derby.iapi.types.WorkHorseForCollatorDatatypes

```
final class WorkHorseForCollatorDatatypes
extends java.lang.Object
```
WorkHorseForCollatorDatatypes class holds on to RuleBasedCollator, and the base SQLChar object for the collation sensitive SQLChar, SQLVarchar, SQLLongvarchar and SQLClob. This class uses RuleBasedCollator and SQLChar object in the collation sensitive methods to do the comparison. The reason for encapsulating this here is that the collation version of SQLChar, SQLVarchar, SQLLongvarchar and SQLClob do not all have to duplicate the code for collation sensitive methods. Instead, they can simply delegate the work to methods defined in this class.

Field Summary

Fields
Modifier and Type	Field	Description
`private java.text.RuleBasedCollator`	`collatorForCharacterDatatypes`	Use this object for collation on character datatype.
`private SQLChar`	`stringData`	collatorForCharacterDatatypes will be used on this SQLChar to determine collationElementsForString.

Constructor Summary

Constructors
Constructor Description

WorkHorseForCollatorDatatypes(java.text.RuleBasedCollator collatorForCharacterDatatypes, SQLChar stringData)

Constructors
Constructor	Description
`WorkHorseForCollatorDatatypes(java.text.RuleBasedCollator collatorForCharacterDatatypes, SQLChar stringData)`

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`(package private) java.text.RuleBasedCollator`	`getCollatorForCollation()`	Get the RuleBasedCollator which is getting used for collation sensitive methods.
`(package private) boolean`	`hasSingleCollationElement()`	Check if the string consists of a single collation element.
`(package private) BooleanDataValue`	`like(DataValueDescriptor pattern)`	This method implements the like function for char (with no escape value).
`(package private) BooleanDataValue`	`like(DataValueDescriptor pattern, DataValueDescriptor escape)`	This method implements the like function for char with an escape value.
`(package private) int`	`stringCompare(SQLChar str1, SQLChar str2)`

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Field Detail
  - collatorForCharacterDatatypes
```
private java.text.RuleBasedCollator collatorForCharacterDatatypes
```
    Use this object for collation on character datatype. This collator object is passed as a parameter to the constructor.
  - stringData
```
private SQLChar stringData
```
    collatorForCharacterDatatypes will be used on this SQLChar to determine collationElementsForString. The collationElementsForString is used by the like method to do Collator specific comparison. This SQLChar object is passed as a parameter to the constructor.
- Constructor Detail
  - WorkHorseForCollatorDatatypes
```
WorkHorseForCollatorDatatypes(java.text.RuleBasedCollator collatorForCharacterDatatypes,
                              SQLChar stringData)
```
- Method Detail
  - stringCompare
```
int stringCompare(SQLChar str1,
                  SQLChar str2)
           throws StandardException
```
    Throws:
    
    StandardException
    
    See Also:
    
    SQLChar.stringCompare(SQLChar, SQLChar)
  - like
```
BooleanDataValue like(DataValueDescriptor pattern)
               throws StandardException
```
    This method implements the like function for char (with no escape value). The difference in this method and the same method in SQLChar is that here we use special Collator object to do the comparison rather than using the Collator object associated with the default jvm locale.
    
    Parameters:
    
    pattern - The pattern to use
    
    Returns:
    
    A SQL boolean value telling whether the first operand is like the second operand
    
    Throws:
    
    StandardException - Thrown on error
  - like
```
BooleanDataValue like(DataValueDescriptor pattern,
                      DataValueDescriptor escape)
               throws StandardException
```
    This method implements the like function for char with an escape value.
    
    Parameters:
    
    pattern - The pattern to use
    
    Returns:
    
    A SQL boolean value telling whether the first operand is like the second operand
    
    Throws:
    
    StandardException - Thrown on error
  - getCollatorForCollation
```
java.text.RuleBasedCollator getCollatorForCollation()
```
    Get the RuleBasedCollator which is getting used for collation sensitive methods.
  - hasSingleCollationElement
```
boolean hasSingleCollationElement()
                           throws StandardException
```
    Check if the string consists of a single collation element.
    
    Returns:
    
    true iff it's a single collation element
    
    Throws:
    
    StandardException
    
    See Also:
    
    CollationElementsInterface.hasSingleCollationElement()

Class WorkHorseForCollatorDatatypes

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

collatorForCharacterDatatypes

stringData

Constructor Detail

WorkHorseForCollatorDatatypes

Method Detail

stringCompare

like

like

getCollatorForCollation

hasSingleCollationElement