BasicSortObserver (Apache Derby V10.14 Internals)

java.lang.Object
- org.apache.derby.impl.sql.execute.BasicSortObserver

All Implemented Interfaces:

SortObserver

Direct Known Subclasses:

AggregateSortObserver, UniqueIndexSortObserver, UniqueWithDuplicateNullsIndexSortObserver
```
public class BasicSortObserver
extends java.lang.Object
implements SortObserver
```
This is the most basic sort observer. It handles distinct sorts and non-distinct sorts.

Field Summary

Fields
Modifier and Type	Field	Description
`protected boolean`	`distinct`
`protected boolean`	`doClone`
`private ExecRow`	`execRow`
`private boolean`	`reuseWrappers`
`private java.util.Vector<DataValueDescriptor[]>`	`vector`

Constructor Summary

Constructors
Constructor	Description
`BasicSortObserver(boolean doClone, boolean distinct, ExecRow execRow, boolean reuseWrappers)`	Simple constructor

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`void`	`addToFreeList(DataValueDescriptor[] objectArray, int maxFreeListSize)`
`boolean`	`deferrable()`	Overridden by subclasses that observe sorters with uniqueness checking.
`boolean`	`deferred()`	Overridden by subclasses that observe sorters with uniqueness checking.
`DataValueDescriptor[]`	`getArrayClone()`
`private DataValueDescriptor[]`	`getClone(DataValueDescriptor[] origArray)`
`DataValueDescriptor[]`	`insertDuplicateKey(DataValueDescriptor[] insertRow, DataValueDescriptor[] existingRow)`	Called prior to inserting a duplicate sort key.
`DataValueDescriptor[]`	`insertNonDuplicateKey(DataValueDescriptor[] insertRow)`	Called prior to inserting a distinct sort key.
`void`	`rememberDuplicate(DataValueDescriptor[] row)`	Overridden by subclasses that observe sorters with uniqueness checking.

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

- Field Detail
  - doClone
```
protected boolean doClone
```
  - distinct
```
protected boolean distinct
```
  - reuseWrappers
```
private boolean reuseWrappers
```
  - execRow
```
private ExecRow execRow
```
  - vector
```
private java.util.Vector<DataValueDescriptor[]> vector
```
- Constructor Detail
  - BasicSortObserver
```
public BasicSortObserver(boolean doClone,
                         boolean distinct,
                         ExecRow execRow,
                         boolean reuseWrappers)
```
    Simple constructor
    
    Parameters:
    
    doClone - If true, then rows that are retained by the sorter will be cloned. This is needed if language is reusing row wrappers.
    
    distinct - If true, toss out duplicates. Otherwise, retain them.
    
    execRow - ExecRow to use as source of clone for store.
    
    reuseWrappers - Whether or not we can reuse the wrappers
- Method Detail
  - insertNonDuplicateKey
```
public DataValueDescriptor[] insertNonDuplicateKey(DataValueDescriptor[] insertRow)
                                            throws StandardException
```
    Called prior to inserting a distinct sort key.
    
    Specified by:
    
    insertNonDuplicateKey in interface SortObserver
    
    Parameters:
    
    insertRow - the current row that the sorter is on the verge of retaining
    
    Returns:
    
    the row to be inserted by the sorter. If null, then nothing is inserted by the sorter. Distinct sorts will want to return null.
    
    Throws:
    
    StandardException - never thrown
  - insertDuplicateKey
```
public DataValueDescriptor[] insertDuplicateKey(DataValueDescriptor[] insertRow,
                                                DataValueDescriptor[] existingRow)
                                         throws StandardException
```
    Called prior to inserting a duplicate sort key.
    
    Specified by:
    
    insertDuplicateKey in interface SortObserver
    
    Parameters:
    
    insertRow - the current row that the sorter is on the verge of retaining. It is a duplicate of existingRow.
    
    existingRow - the row that is already in the the sorter which is a duplicate of insertRow
    
    Returns:
    
    the row to be inserted by the sorter. If null, then nothing is inserted by the sorter. Distinct sorts will want to return null.
    
    Throws:
    
    StandardException - never thrown
  - addToFreeList
```
public void addToFreeList(DataValueDescriptor[] objectArray,
                          int maxFreeListSize)
```
    Specified by:
    
    addToFreeList in interface SortObserver
  - getArrayClone
```
public DataValueDescriptor[] getArrayClone()
                                    throws StandardException
```
    Specified by:
    
    getArrayClone in interface SortObserver
    
    Throws:
    
    StandardException
  - getClone
```
private DataValueDescriptor[] getClone(DataValueDescriptor[] origArray)
```
  - deferred
```
public boolean deferred()
```
    Description copied from interface: SortObserver
    
    Overridden by subclasses that observe sorters with uniqueness checking.
    
    Specified by:
    
    deferred in interface SortObserver
    
    Returns:
    
    true if constraint mode of the index's constraint is effectively deferred. Any SortObserver implementations that implement uniqueness checking need to keep track of this information.
  - deferrable
```
public boolean deferrable()
```
    Description copied from interface: SortObserver
    
    Overridden by subclasses that observe sorters with uniqueness checking.
    
    Specified by:
    
    deferrable in interface SortObserver
    
    Returns:
    
    true if the index's constraint is deferrable. Any SortObserver implementations that implement uniqueness checking need to keep track of this information.
  - rememberDuplicate
```
public void rememberDuplicate(DataValueDescriptor[] row)
                       throws StandardException
```
    Description copied from interface: SortObserver
    
    Overridden by subclasses that observe sorters with uniqueness checking. Will be called by sorters iff deferrable() and deferred() and uniqueness violation, so implementations that sometimes return true to these must implement this method to save duplicate information till commit time.
    
    Specified by:
    
    rememberDuplicate in interface SortObserver
    
    Parameters:
    
    row - data of offending key
    
    Throws:
    
    StandardException - standard error policy

Class BasicSortObserver

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

doClone

distinct

reuseWrappers

execRow

vector

Constructor Detail

BasicSortObserver

Method Detail

insertNonDuplicateKey

insertDuplicateKey

addToFreeList

getArrayClone

getClone

deferred

deferrable

rememberDuplicate