IndexData (Jackcess 4.0.7 API)

java.lang.Object
- com.healthmarketscience.jackcess.impl.IndexData

```
public class IndexData
extends Object
```
Access table index data. This is the actual data which backs a logical Index, where one or more logical indexes can be backed by the same index data.

Author:

Tim McCune

Nested Class Summary

Nested Classes
Modifier and Type	Class and Description
`static class`	`IndexData.ColumnDescriptor` Information about the columns in an index.
`static class`	`IndexData.Entry` A single leaf entry in an index (points to a single row)
`class`	`IndexData.EntryCursor` Utility class to traverse the entries in the Index.
`static class`	`IndexData.EntryType` type attributes for Entries which simplify comparisons
`static class`	`IndexData.PendingChange` Utility class which maintains information about a pending index update.

Field Summary

Fields
Modifier and Type	Field and Description
`static byte`	`ASCENDING_COLUMN_FLAG`
`static Comparator<byte[]>`	`BYTE_CODE_COMPARATOR`
`static IndexData.Entry`	`FIRST_ENTRY` special entry which is less than any other entry
`static byte`	`IGNORE_NULLS_INDEX_FLAG`
`static IndexData.Entry`	`LAST_ENTRY` special entry which is greater than any other entry
`static int`	`MAX_COLUMNS` Max number of columns in an index
`static Object`	`MAX_VALUE` special object which will always be greater than any other value, when searching for an index entry range in a multi-value index
`static Object`	`MIN_VALUE` special object which will always be greater than any other value, when searching for an index entry range in a multi-value index
`static byte`	`REQUIRED_INDEX_FLAG`
`static byte`	`UNIQUE_INDEX_FLAG`
`static byte`	`UNKNOWN_INDEX_FLAG`

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`static void`	`commitAll(IndexData.PendingChange change)`
`Object[]`	`constructIndexRow(Map<String,?> row)` Constructs an array of values appropriate for this index from the given column values.
`Object[]`	`constructIndexRow(String colName, Object value)` Constructs an array of values appropriate for this index from the given column value.
`Object[]`	`constructIndexRowFromEntry(Object... values)` Constructs an array of values appropriate for this index from the given column values, expected to match the columns for this index.
`Object[]`	`constructPartialIndexRow(Object filler, Map<String,?> row)` Constructs an array of values appropriate for this index from the given column values, possibly only using a subset of the given values.
`Object[]`	`constructPartialIndexRow(Object filler, String colName, Object value)` Constructs an array of values appropriate for this index from the given column value, which must be the first column of the index.
`Object[]`	`constructPartialIndexRowFromEntry(Object filler, Object... values)` Constructs an array of values appropriate for this index from the given column values, possibly only providing a prefix subset of the index columns (at least one value must be provided).
`static IndexData`	`create(TableImpl table, ByteBuffer tableBuffer, int number, JetFormat format)` Creates an IndexData appropriate for the given table, using information from the given table definition buffer.
`IndexData.EntryCursor`	`cursor()` Gets a new cursor for this index.
`IndexData.EntryCursor`	`cursor(Object[] startRow, boolean startInclusive, Object[] endRow, boolean endInclusive)` Gets a new cursor for this index, narrowed to the range defined by the given startRow and endRow.
`void`	`deleteRow(Object[] row, RowIdImpl rowId)` Removes a row from this index
`int`	`getColumnCount()`
`List<IndexData.ColumnDescriptor>`	`getColumns()` Returns the Columns for this index (unmodifiable)
`int`	`getEntryCount()` Returns the number of index entries in the index.
`JetFormat`	`getFormat()`
`int`	`getIndexDataNumber()`
`List<Index>`	`getIndexes()`
`byte`	`getIndexFlags()`
`String`	`getName()`
`int`	`getOwnedPageCount()` Returns the number of database pages owned by this index data.
`PageChannel`	`getPageChannel()`
`Index`	`getPrimaryIndex()`
`TableImpl`	`getTable()`
`int`	`getUniqueEntryCount()`
`int`	`getUniqueEntryCountOffset()`
`void`	`initialize()` Forces initialization of this index (actual parsing of index pages).
`boolean`	`isInitialized()` Whether or not the complete index state has been read.
`boolean`	`isRequired()` Whether or not values are required in the columns.
`boolean`	`isUnique()` Whether or not index entries must be unique.
`IndexData.PendingChange`	`prepareAddRow(Object[] row, RowIdImpl rowId, IndexData.PendingChange nextChange)` Prepares to add a row to this index.
`IndexData.PendingChange`	`prepareUpdateRow(Object[] oldRow, RowIdImpl rowId, Object[] newRow, IndexData.PendingChange nextChange)` Prepares to update a row in this index.
`void`	`read(ByteBuffer tableBuffer, List<ColumnImpl> availableColumns)` Read the rest of the index info from a tableBuffer
`static void`	`rollbackAll(IndexData.PendingChange change)`
`boolean`	`shouldIgnoreNulls()` Whether or not `null` values are actually recorded in the index.
`String`	`toString()`
`void`	`update()` Writes the current index state to the database.
`void`	`validate(boolean forceLoad)` Used by unit tests to validate the internal status of the index.

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

- Field Detail
  - FIRST_ENTRY
```
public static final IndexData.Entry FIRST_ENTRY
```
    special entry which is less than any other entry
  - LAST_ENTRY
```
public static final IndexData.Entry LAST_ENTRY
```
    special entry which is greater than any other entry
  - MAX_VALUE
```
public static final Object MAX_VALUE
```
    special object which will always be greater than any other value, when searching for an index entry range in a multi-value index
  - MIN_VALUE
```
public static final Object MIN_VALUE
```
    special object which will always be greater than any other value, when searching for an index entry range in a multi-value index
  - MAX_COLUMNS
```
public static final int MAX_COLUMNS
```
    Max number of columns in an index
    
    See Also:
    
    Constant Field Values
  - ASCENDING_COLUMN_FLAG
```
public static final byte ASCENDING_COLUMN_FLAG
```
    See Also:
    
    Constant Field Values
  - UNIQUE_INDEX_FLAG
```
public static final byte UNIQUE_INDEX_FLAG
```
    See Also:
    
    Constant Field Values
  - IGNORE_NULLS_INDEX_FLAG
```
public static final byte IGNORE_NULLS_INDEX_FLAG
```
    See Also:
    
    Constant Field Values
  - REQUIRED_INDEX_FLAG
```
public static final byte REQUIRED_INDEX_FLAG
```
    See Also:
    
    Constant Field Values
  - UNKNOWN_INDEX_FLAG
```
public static final byte UNKNOWN_INDEX_FLAG
```
    See Also:
    
    Constant Field Values
  - BYTE_CODE_COMPARATOR
```
public static final Comparator<byte[]> BYTE_CODE_COMPARATOR
```
- Method Detail
  - create
```
public static IndexData create(TableImpl table,
                               ByteBuffer tableBuffer,
                               int number,
                               JetFormat format)
                        throws IOException
```
    Creates an IndexData appropriate for the given table, using information from the given table definition buffer.
    
    Throws:
    
    IOException
  - getName
```
public String getName()
```
  - getTable
```
public TableImpl getTable()
```
  - getFormat
```
public JetFormat getFormat()
```
  - getPageChannel
```
public PageChannel getPageChannel()
```
  - getPrimaryIndex
```
public Index getPrimaryIndex()
```
    Returns:
    
    the "main" logical index which is backed by this data.
  - getIndexes
```
public List<Index> getIndexes()
```
    Returns:
    
    All of the Indexes backed by this data (unmodifiable List)
  - getIndexFlags
```
public byte getIndexFlags()
```
  - getIndexDataNumber
```
public int getIndexDataNumber()
```
  - getUniqueEntryCount
```
public int getUniqueEntryCount()
```
  - getUniqueEntryCountOffset
```
public int getUniqueEntryCountOffset()
```
  - shouldIgnoreNulls
```
public boolean shouldIgnoreNulls()
```
    Whether or not null values are actually recorded in the index.
  - isUnique
```
public boolean isUnique()
```
    Whether or not index entries must be unique.
    Some notes about uniqueness:
    - Access does not seem to consider multiple null entries invalid for a unique index
    - text indexes collapse case, and Access seems to compare only the index entry bytes, therefore two strings which differ only in case will violate the unique constraint
  - isRequired
```
public boolean isRequired()
```
    Whether or not values are required in the columns.
  - getColumns
```
public List<IndexData.ColumnDescriptor> getColumns()
```
    Returns the Columns for this index (unmodifiable)
  - getColumnCount
```
public int getColumnCount()
```
  - isInitialized
```
public boolean isInitialized()
```
    Whether or not the complete index state has been read.
  - getOwnedPageCount
```
public int getOwnedPageCount()
```
    Returns the number of database pages owned by this index data.
    
    Usage:
    
    Intermediate: This method requires moderate API knowledge.
  - validate
```
public void validate(boolean forceLoad)
              throws IOException
```
    Used by unit tests to validate the internal status of the index.
    
    Parameters:
    
    forceLoad - if false only validate currently loaded index data pages, otherwise, load and validate all index pages
    
    Throws:
    
    IOException
    
    Usage:
    
    Advanced: This method is for advanced/internal use.
  - getEntryCount
```
public int getEntryCount()
                  throws IOException
```
    Returns the number of index entries in the index. Only called by unit tests.
    Forces index initialization.
    
    Throws:
    
    IOException
    
    Usage:
    
    Advanced: This method is for advanced/internal use.
  - initialize
```
public void initialize()
                throws IOException
```
    Forces initialization of this index (actual parsing of index pages). normally, the index will not be initialized until the entries are actually needed.
    
    Throws:
    
    IOException
  - update
```
public void update()
            throws IOException
```
    Writes the current index state to the database.
    Forces index initialization.
    
    Throws:
    
    IOException
  - read
```
public void read(ByteBuffer tableBuffer,
                 List<ColumnImpl> availableColumns)
          throws IOException
```
    Read the rest of the index info from a tableBuffer
    
    Parameters:
    
    tableBuffer - table definition buffer to read from initial info
    
    availableColumns - Columns that this index may use
    
    Throws:
    
    IOException
  - prepareAddRow
```
public IndexData.PendingChange prepareAddRow(Object[] row,
                                             RowIdImpl rowId,
                                             IndexData.PendingChange nextChange)
                                      throws IOException
```
    Prepares to add a row to this index. All constraints are checked before this method returns.
    Forces index initialization.
    
    Parameters:
    
    row - Row to add
    
    rowId - rowId of the row to be added
    
    Returns:
    
    a PendingChange which can complete the addition or roll it back
    
    Throws:
    
    IOException
  - prepareUpdateRow
```
public IndexData.PendingChange prepareUpdateRow(Object[] oldRow,
                                                RowIdImpl rowId,
                                                Object[] newRow,
                                                IndexData.PendingChange nextChange)
                                         throws IOException
```
    Prepares to update a row in this index. All constraints are checked before this method returns.
    Forces index initialization.
    
    Parameters:
    
    oldRow - Row to be removed
    
    newRow - Row to be added
    
    rowId - rowId of the row to be updated
    
    Returns:
    
    a PendingChange which can complete the update or roll it back
    
    Throws:
    
    IOException
  - deleteRow
```
public void deleteRow(Object[] row,
                      RowIdImpl rowId)
               throws IOException
```
    Removes a row from this index
    Forces index initialization.
    
    Parameters:
    
    row - Row to remove
    
    rowId - rowId of the row to be removed
    
    Throws:
    
    IOException
  - commitAll
```
public static void commitAll(IndexData.PendingChange change)
                      throws IOException
```
    Throws:
    
    IOException
  - rollbackAll
```
public static void rollbackAll(IndexData.PendingChange change)
                        throws IOException
```
    Throws:
    
    IOException
  - cursor
```
public IndexData.EntryCursor cursor()
                             throws IOException
```
    Gets a new cursor for this index.
    Forces index initialization.
    
    Throws:
    
    IOException
  - cursor
```
public IndexData.EntryCursor cursor(Object[] startRow,
                                    boolean startInclusive,
                                    Object[] endRow,
                                    boolean endInclusive)
                             throws IOException
```
    Gets a new cursor for this index, narrowed to the range defined by the given startRow and endRow.
    Forces index initialization.
    
    Parameters:
    
    startRow - the first row of data for the cursor, or null for the first entry
    
    startInclusive - whether or not startRow is inclusive or exclusive
    
    endRow - the last row of data for the cursor, or null for the last entry
    
    endInclusive - whether or not endRow is inclusive or exclusive
    
    Throws:
    
    IOException
  - constructIndexRowFromEntry
```
public Object[] constructIndexRowFromEntry(Object... values)
```
    Constructs an array of values appropriate for this index from the given column values, expected to match the columns for this index.
    
    Returns:
    
    the appropriate sparse array of data
    
    Throws:
    
    IllegalArgumentException - if the wrong number of values are provided
  - constructPartialIndexRowFromEntry
```
public Object[] constructPartialIndexRowFromEntry(Object filler,
                                                  Object... values)
```
    Constructs an array of values appropriate for this index from the given column values, possibly only providing a prefix subset of the index columns (at least one value must be provided). If a prefix entry is provided, any missing, trailing index entry values will use the given filler value.
    
    Returns:
    
    the appropriate sparse array of data
    
    Throws:
    
    IllegalArgumentException - if at least one value is not provided
  - constructIndexRow
```
public Object[] constructIndexRow(String colName,
                                  Object value)
```
    Constructs an array of values appropriate for this index from the given column value.
    
    Returns:
    
    the appropriate sparse array of data or null if not all columns for this index were provided
  - constructPartialIndexRow
```
public Object[] constructPartialIndexRow(Object filler,
                                         String colName,
                                         Object value)
```
    Constructs an array of values appropriate for this index from the given column value, which must be the first column of the index. Any missing, trailing index entry values will use the given filler value.
    
    Returns:
    
    the appropriate sparse array of data or null if no prefix list of columns for this index were provided
  - constructIndexRow
```
public Object[] constructIndexRow(Map<String,?> row)
```
    Constructs an array of values appropriate for this index from the given column values.
    
    Returns:
    
    the appropriate sparse array of data or null if not all columns for this index were provided
  - constructPartialIndexRow
```
public Object[] constructPartialIndexRow(Object filler,
                                         Map<String,?> row)
```
    Constructs an array of values appropriate for this index from the given column values, possibly only using a subset of the given values. A partial row can be created if one or more prefix column values are provided. If a prefix can be found, any missing, trailing index entry values will use the given filler value.
    
    Returns:
    
    the appropriate sparse array of data or null if no prefix list of columns for this index were provided
  - toString
```
public String toString()
```
    Overrides:
    
    toString in class Object

Class IndexData

Nested Class Summary

Field Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

FIRST_ENTRY

LAST_ENTRY

MAX_VALUE

MIN_VALUE

MAX_COLUMNS

ASCENDING_COLUMN_FLAG

UNIQUE_INDEX_FLAG

IGNORE_NULLS_INDEX_FLAG

REQUIRED_INDEX_FLAG

UNKNOWN_INDEX_FLAG

BYTE_CODE_COMPARATOR

Method Detail

create

getName

getTable

getFormat

getPageChannel

getPrimaryIndex

getIndexes

getIndexFlags

getIndexDataNumber

getUniqueEntryCount

getUniqueEntryCountOffset

shouldIgnoreNulls

isUnique

isRequired

getColumns

getColumnCount

isInitialized

getOwnedPageCount

validate

getEntryCount

initialize

update

read

prepareAddRow

prepareUpdateRow

deleteRow

commitAll

rollbackAll

cursor

cursor

constructIndexRowFromEntry

constructPartialIndexRowFromEntry

constructIndexRow

constructPartialIndexRow

constructIndexRow

constructPartialIndexRow

toString