DeletionInfo (apache-cassandra API)
Date: 2018-02-12

org.apache.cassandra.db

## Class DeletionInfo

- java.lang.Object
- - org.apache.cassandra.db.DeletionInfo

- All Implemented Interfaces:
    IMeasurableMemory

      public class DeletionInfo
      extends java.lang.Object
      implements IMeasurableMemory

  A combination of a top-level (or row) tombstone and range tombstones describing the deletions within a `ColumnFamily` (or row).

- - ### Nested Class Summary

    Nested Classes
    Modifier and Type | Class and Description
    --- | ---
    `class` | `DeletionInfo.InOrderTester` This object allow testing whether a given column (name/timestamp) is deleted or not by this DeletionInfo, assuming that the columns given to this object are passed in forward or reversed comparator sorted order.
    `static class` | `DeletionInfo.Serializer`

  - ### Constructor Summary

    Constructors
    Constructor and Description
    `DeletionInfo(Composite start, Composite end, java.util.Comparator<Composite> comparator, long markedForDeleteAt, int localDeletionTime)`
    `DeletionInfo(DeletionTime topLevel)`
    `DeletionInfo(long markedForDeleteAt, int localDeletionTime)` Creates a DeletionInfo with only a top-level (row) tombstone.
    `DeletionInfo(RangeTombstone rangeTombstone, java.util.Comparator<Composite> comparator)`

  - ### Method Summary

    All Methods Static Methods Instance Methods Concrete Methods
    Modifier and Type | Method and Description
    --- | ---
    `DeletionInfo` | `add(DeletionInfo newInfo)` Combines another DeletionInfo with this one and returns the result.
    `void` | `add(DeletionTime newInfo)` Potentially replaces the top-level tombstone with another, keeping whichever has the higher markedForDeleteAt timestamp.
    `void` | `add(RangeTombstone tombstone, java.util.Comparator<Composite> comparator)`
    `DeletionInfo` | `copy()`
    `DeletionInfo` | `copy(AbstractAllocator allocator)`
    `int` | `dataSize()`
    `DeletionInfo` | `diff(DeletionInfo superset)` Evaluates difference between this deletion info and superset for read repair
    `boolean` | `equals(java.lang.Object o)`
    `DeletionTime` | `getTopLevelDeletion()` Returns the top-level (or "row") tombstone.
    `int` | `hashCode()`
    `boolean` | `hasPurgeableTombstones(int gcBefore)` Returns true if `purge` would remove the top-level tombstone or any of the range tombstones, false otherwise.
    `boolean` | `hasRanges()`
    `DeletionInfo.InOrderTester` | `inOrderTester()` Returns a new `DeletionInfo.InOrderTester` in forward order.
    `DeletionInfo.InOrderTester` | `inOrderTester(boolean reversed)` Returns a new `DeletionInfo.InOrderTester` given the order in which columns will be passed to it.
    `boolean` | `isDeleted(Cell cell)` Return whether a given cell is deleted by the container having this deletion info.
    `boolean` | `isLive()` Returns whether this DeletionInfo is live, that is deletes no columns.
    `static DeletionInfo` | `live()` Returns a new DeletionInfo that has no top-level tombstone or any range tombstones.
    `long` | `maxTimestamp()` Returns the maximum timestamp in any of the range tombstones or the top-level tombstone.
    `boolean` | `mayModify(DeletionInfo delInfo)` Whether this deletion info may modify the provided one if added to it.
    `long` | `minTimestamp()` Returns the minimum timestamp in any of the range tombstones or the top-level tombstone.
    `void` | `purge(int gcBefore)` Purge every tombstones that are older than `gcbefore`.
    `int` | `rangeCount()`
    `RangeTombstone` | `rangeCovering(Composite name)`
    `java.util.Iterator<RangeTombstone>` | `rangeIterator()`
    `java.util.Iterator<RangeTombstone>` | `rangeIterator(Composite start, Composite finish)`
    `java.lang.String` | `toString()`
    `long` | `unsharedHeapSize()`
    `void` | `updateAllTimestamp(long timestamp)`
    `void` | `updateDigest(java.security.MessageDigest digest)` Digests deletion info.

    - ### Methods inherited from class java.lang.Object

      `clone, finalize, getClass, notify, notifyAll, wait, wait, wait`

- - ### Constructor Detail

    - #### DeletionInfo

          public DeletionInfo(long markedForDeleteAt,
                              int localDeletionTime)

      Creates a DeletionInfo with only a top-level (row) tombstone.
      Parameters:
        `markedForDeleteAt` - the time after which the entire row should be considered deleted
        `localDeletionTime` - what time the deletion write was applied locally (for purposes of purging the tombstone after gc_grace_seconds).

    - #### DeletionInfo

          public DeletionInfo(DeletionTime topLevel)

    - #### DeletionInfo

          public DeletionInfo(Composite start,
                              Composite end,
                              java.util.Comparator<Composite> comparator,
                              long markedForDeleteAt,
                              int localDeletionTime)

    - #### DeletionInfo

          public DeletionInfo(RangeTombstone rangeTombstone,
                              java.util.Comparator<Composite> comparator)

  - ### Method Detail

    - #### live

          public static DeletionInfo live()

      Returns a new DeletionInfo that has no top-level tombstone or any range tombstones.

    - #### copy

          public DeletionInfo copy()

    - #### copy

          public DeletionInfo copy(AbstractAllocator allocator)

    - #### isLive

          public boolean isLive()

      Returns whether this DeletionInfo is live, that is deletes no columns.

    - #### isDeleted

          public boolean isDeleted(Cell cell)

      Return whether a given cell is deleted by the container having this deletion info.
      Parameters:
        `cell` - the cell to check.
      Returns:
        true if the cell is deleted, false otherwise

    - #### inOrderTester

          public DeletionInfo.InOrderTester inOrderTester()

      Returns a new `DeletionInfo.InOrderTester` in forward order.

    - #### inOrderTester

          public DeletionInfo.InOrderTester inOrderTester(boolean reversed)

      Returns a new `DeletionInfo.InOrderTester` given the order in which columns will be passed to it.

    - #### purge

          public void purge(int gcBefore)

      Purge every tombstones that are older than `gcbefore`.
      Parameters:
        `gcBefore` - timestamp (in seconds) before which tombstones should be purged

    - #### diff

          public DeletionInfo diff(DeletionInfo superset)

      Evaluates difference between this deletion info and superset for read repair
      Returns:
        the difference between the two, or LIVE if no difference

    - #### updateDigest

          public void updateDigest(java.security.MessageDigest digest)

      Digests deletion info. Used to trigger read repair on mismatch.

    - #### hasPurgeableTombstones

          public boolean hasPurgeableTombstones(int gcBefore)

      Returns true if `purge` would remove the top-level tombstone or any of the range tombstones, false otherwise.
      Parameters:
        `gcBefore` - timestamp (in seconds) before which tombstones should be purged

    - #### add

          public void add(DeletionTime newInfo)

      Potentially replaces the top-level tombstone with another, keeping whichever has the higher markedForDeleteAt timestamp.
      Parameters:
        `newInfo` -

    - #### add

          public void add(RangeTombstone tombstone,
                          java.util.Comparator<Composite> comparator)

    - #### add

          public DeletionInfo add(DeletionInfo newInfo)

      Combines another DeletionInfo with this one and returns the result. Whichever top-level tombstone has the higher markedForDeleteAt timestamp will be kept, along with its localDeletionTime. The range tombstones will be combined.
      Returns:
        this object.

    - #### minTimestamp

          public long minTimestamp()

      Returns the minimum timestamp in any of the range tombstones or the top-level tombstone.

    - #### maxTimestamp

          public long maxTimestamp()

      Returns the maximum timestamp in any of the range tombstones or the top-level tombstone.

    - #### getTopLevelDeletion

          public DeletionTime getTopLevelDeletion()

      Returns the top-level (or "row") tombstone.

    - #### rangeIterator

          public java.util.Iterator<RangeTombstone> rangeIterator()

    - #### rangeIterator

          public java.util.Iterator<RangeTombstone> rangeIterator(Composite start,
                                                                  Composite finish)

    - #### rangeCovering

          public RangeTombstone rangeCovering(Composite name)

    - #### dataSize

          public int dataSize()

    - #### hasRanges

          public boolean hasRanges()

    - #### rangeCount

          public int rangeCount()

    - #### mayModify

          public boolean mayModify(DeletionInfo delInfo)

      Whether this deletion info may modify the provided one if added to it.

    - #### toString

          public java.lang.String toString()

      Overrides:
        `toString` in class `java.lang.Object`

    - #### updateAllTimestamp

          public void updateAllTimestamp(long timestamp)

    - #### equals

          public boolean equals(java.lang.Object o)

      Overrides:
        `equals` in class `java.lang.Object`

    - #### hashCode

          public final int hashCode()

      Overrides:
        `hashCode` in class `java.lang.Object`

    - #### unsharedHeapSize

          public long unsharedHeapSize()

      Specified by:
        `unsharedHeapSize` in interface `IMeasurableMemory`
      Returns:
        the amount of on-heap memory retained by the object that might be reclaimed if the object were reclaimed, i.e. it should try to exclude globally cached data where possible, or counting portions of arrays that are referenced by the object but used by other objects only (e.g. slabbed byte-buffers), etc.

Copyright © 2018 The Apache Software Foundation