ColumnOrderedKey

java.lang.Object
- org.datanucleus.store.rdbms.key.Key
- - org.datanucleus.store.rdbms.key.ColumnOrderedKey

Direct Known Subclasses:

CandidateKey, Index
```
public abstract class ColumnOrderedKey
extends Key
```
Representation of a key that has columns with specified ordering (ascending/descending) for each column (if required).

Field Summary

Fields
Modifier and Type	Field	Description
`protected java.util.List<java.lang.Boolean>`	`columnOrdering`	Column ordering.
`protected java.util.Map<java.lang.String,java.lang.String>`	`extensions`

Fields inherited from class org.datanucleus.store.rdbms.key.Key
columns, name, table

Constructor Summary

Constructors
Constructor Description

ColumnOrderedKey(Table table, java.util.Map<java.lang.String,java.lang.String> extensions)

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`void`	`addColumn(Column col)`	Class to add a column to the key
`java.lang.String`	`getColumnList(boolean includeOrdering)`	Method to return the list of columns which the key applies to.
`java.lang.String`	`getValueForExtension(java.lang.String key)`
`void`	`setColumn(int seq, Column col)`	Sets a column in a specified position `seq` for this index.
`void`	`setColumnOrdering(java.lang.String ordering)`

Methods inherited from class org.datanucleus.store.rdbms.key.Key
assertSameDatastoreObject, equals, getColumnList, getColumnList, getColumns, getName, getNumberOfColumns, getTable, hashCode, setListMinimumSize, setName

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

- Field Detail
  - columnOrdering
```
protected java.util.List<java.lang.Boolean> columnOrdering
```
    Column ordering. True implies ascending order.
  - extensions
```
protected java.util.Map<java.lang.String,java.lang.String> extensions
```
- Constructor Detail
  - ColumnOrderedKey
```
public ColumnOrderedKey(Table table,
                        java.util.Map<java.lang.String,java.lang.String> extensions)
```
- Method Detail
  - getValueForExtension
```
public java.lang.String getValueForExtension(java.lang.String key)
```
  - addColumn
```
public void addColumn(Column col)
```
    Class to add a column to the key
    
    Overrides:
    
    addColumn in class Key
    
    Parameters:
    
    col - The column to add
  - setColumnOrdering
```
public void setColumnOrdering(java.lang.String ordering)
```
  - setColumn
```
public void setColumn(int seq,
                      Column col)
```
    Sets a column in a specified position seq for this index.
    
    Overrides:
    
    setColumn in class Key
    
    Parameters:
    
    seq - the specified position for the col
    
    col - the Column
  - getColumnList
```
public java.lang.String getColumnList(boolean includeOrdering)
```
    Method to return the list of columns which the key applies to.
    
    Parameters:
    
    includeOrdering - Whether to include ordering in the column list when it is specified
    
    Returns:
    
    The column list.