com.faunos.skwish.sys.filters
Class ReadOnlyFilterSegment

java.lang.Object
  com.faunos.skwish.Segment
      com.faunos.skwish.sys.filters.FilterSegment
          com.faunos.skwish.sys.filters.ReadOnlyFilterSegment

All Implemented Interfaces:

Range

public class ReadOnlyFilterSegment
extends FilterSegment

A read-only view of an underlying segment.

Author:

Babak Farhang

See Also:

On the read-only property

Field Summary

Fields inherited from class com.faunos.skwish.sys.filters.FilterSegment

inner

Fields inherited from class com.faunos.skwish.Segment

validator

Constructor Summary

ReadOnlyFilterSegment(Segment inner)
Creates and returns a read-only view of the given inner instance.

Method Summary

void	delete(long id) Deletes the entry with the specified id.
void	delete(long id, int count) Deletes count entries starting at the entry with the specified id.
void	delete(long id, int count, boolean purge) Deletes count entries starting at the entry with the specified id.
long	insertEntry(ByteBuffer buffer) Inserts the given entry and returns the entry's ID.
long	insertEntry(ReadableByteChannel entry) Inserts the entry represented by the given channel.
boolean	isReadOnly() Determines whether this instance is read-only (unmodifiable).
long	killNext() Kills the next entry ID.
long	killNext(int count) Kills the next count entry IDs.

Methods inherited from class com.faunos.skwish.sys.filters.FilterSegment

getBaseId, getEntry, getEntryChannel, getEntryCount, getEntryPart, getEntrySize, getNextId

Methods inherited from class com.faunos.skwish.Segment

contains, getEntry, getEntrySize, getEntryStream, hi, isDeleted, isDeleted, lo, toString

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

ReadOnlyFilterSegment

public ReadOnlyFilterSegment(Segment inner)

Creates and returns a read-only view of the given inner instance.

Method Detail

isReadOnly

public final boolean isReadOnly()

Description copied from class: Segment

Determines whether this instance is read-only (unmodifiable).

Overrides:

isReadOnly in class FilterSegment

Returns:

true

See Also:

Write operations

delete

public final void delete(long id)
                  throws UnsupportedOperationException,
                         IOException

Description copied from class: Segment

Deletes the entry with the specified id. The entry is marked as deleted; the deleted contents will be purged whenever the segment is compacted or merged with another segment.

Overrides:

delete in class Segment

Parameters:

id - the ID of the entry to be deleted. Must be a valid ID in this segment [baseId, baseId + entryCount)

Throws:

UnsupportedOperationException

IOException

delete

public final void delete(long id,
                         int count)
                  throws UnsupportedOperationException,
                         IOException

Description copied from class: Segment

Deletes count entries starting at the entry with the specified id. The entries are marked as deleted; the deleted contents will be purged whenever the segment is compacted or merged with another segment.

Overrides:

delete in class Segment

Parameters:

id - the ID of the first entry to be deleted. Must be a valid ID in this segment [baseId, baseId + entryCount)

count - the number of entries to be deleted. Specifies a range of IDs to be deleted: [id, id + count). The range of IDs must be valid entries within this segment; o.w. an exception is raised.

Throws:

UnsupportedOperationException

IOException

delete

public final void delete(long id,
                         int count,
                         boolean purge)
                  throws UnsupportedOperationException,
                         IOException

Description copied from class: Segment

Deletes count entries starting at the entry with the specified id. The contents of the deleted entries may optionally be requested to be purged (overwritten) immediately; o.w. the deleted contents will be purged whenever the segment is compacted or merged with another segment.

Note that purging is not part of any transaction semantic; whether or not a purge immediately takes place on its being signaled is implementation-dependent.

Overrides:

delete in class FilterSegment

Parameters:

id - the ID of the first entry to be deleted. Must be a valid ID in this segment [baseId, baseId + entryCount)

count - the number of entries to be deleted. Specifies a range of IDs to be deleted: [id, id + count). The range of IDs must be valid entries within this segment; o.w. an exception is raised.

purge - if true, the contents of the deleted entries are signaled to be purged (overwritten) immediately; o.w. the contents will be deleted on the next time the segment is compacted.

Throws:

UnsupportedOperationException

IOException

insertEntry

public final long insertEntry(ByteBuffer buffer)
                       throws UnsupportedOperationException,
                              IOException

Description copied from class: Segment

Inserts the given entry and returns the entry's ID. The contents of the entry is understood to be the remaining contents in the given buffer.

Overrides:

insertEntry in class FilterSegment

Parameters:

buffer - they contents of the entry

Returns:

the ID assigned to the entry

Throws:

UnsupportedOperationException

IOException

insertEntry

public final long insertEntry(ReadableByteChannel entry)
                       throws UnsupportedOperationException,
                              IOException

Description copied from class: Segment

Inserts the entry represented by the given channel. The contents are of the entry is understood to be the entire remaining contents in the specified channel.

This is the most efficient method for inserting a large-size entry (even one that doesn't fit in memory).

Overrides:

insertEntry in class FilterSegment

Throws:

UnsupportedOperationException

IOException

killNext

public final long killNext()
                    throws UnsupportedOperationException,
                           IOException

Description copied from class: Segment

Kills the next entry ID. A killed entry is an entry that begins (and ends) life in the deleted state.

Overrides:

killNext in class Segment

Returns:

the value that getNextId() returns after this method has completed

Throws:

UnsupportedOperationException

IOException

killNext

public final long killNext(int count)
                    throws UnsupportedOperationException,
                           IOException

Description copied from class: Segment

Kills the next count entry IDs. A killed entry is an entry that begins (and ends) life in the deleted state.

Overrides:

killNext in class FilterSegment

Parameters:

count - the number of entries to kill (must be greater than 1)

Returns:

the value that getNextId() returns after this method has completed

Throws:

UnsupportedOperationException

IOException