com.mware.ge.store.mutations

Class StoreMutation

java.lang.Object

com.mware.ge.store.mutations.StoreMutation

public class StoreMutation
extends Object

Mutation represents an action that manipulates a row in a table. A mutation holds a list of column/value pairs that represent an atomic set of modifications to make to a row.

Convenience methods which takes columns and value as CharSequence (String implements CharSequence) are provided. CharSequence is converted to UTF-8 by constructing a new Text object.

When always passing in the same data as a CharSequence/String, it's probably more efficient to call the Text put methods. This way the data is only encoded once and only one Text object is created.

All of the put methods append data to the mutation; they do not overwrite anything that was previously put. The mutation holds a list of all columns/values that were put into it.

The putDelete() methods do not remove something that was previously added to the mutation; rather, they indicate that Accumulo should insert a delete marker for that row column. A delete marker effectively hides entries for that row column with a timestamp earlier than the marker's. (The hidden data is eventually removed during Accumulo garbage collection.)

Field Summary

Fields

Modifier and Type	Field and Description
static byte[]	EMPTY_BYTES

Constructor Summary

Constructors

Constructor and Description
StoreMutation() Creates a new mutation.
StoreMutation(byte[] row) Creates a new mutation.
StoreMutation(byte[] row, int start, int length) Creates a new mutation.
StoreMutation(byte[] row, int start, int length, int initialBufferSize) Creates a new mutation.
StoreMutation(String rowId) Creates a new mutation.

Method Summary

Modifier and Type	Method and Description
static ByteBuffer	encode(String string, boolean replace) Converts the provided String to bytes using the UTF-8 encoding.
byte[]	getData()
byte[]	getRow() Gets the row ID for this mutation.
List<StoreColumnUpdate>	getUpdates() Gets the modifications and deletions in this mutation.
protected StoreColumnUpdate	newColumnUpdate(byte[] cf, byte[] cq, byte[] cv, boolean hasts, long ts, boolean deleted, byte[] val)
void	put(CharSequence columnFamily, CharSequence columnQualifier, byte[] value) Puts a modification in this mutation.
void	put(CharSequence columnFamily, CharSequence columnQualifier, byte[] columnVisibility, boolean hasts, long timestamp, boolean deleted, byte[] value) Puts a modification in this mutation.
void	put(CharSequence columnFamily, CharSequence columnQualifier, ColumnVisibility columnVisibility, byte[] value) Puts a modification in this mutation.
void	put(CharSequence columnFamily, CharSequence columnQualifier, ColumnVisibility columnVisibility, long timestamp, byte[] value) Puts a modification in this mutation.
void	put(CharSequence columnFamily, CharSequence columnQualifier, long timestamp, byte[] value) Puts a modification in this mutation.
void	putDelete(CharSequence columnFamily, CharSequence columnQualifier) Puts a deletion in this mutation.
void	putDelete(CharSequence columnFamily, CharSequence columnQualifier, ColumnVisibility columnVisibility) Puts a deletion in this mutation.
void	putDelete(CharSequence columnFamily, CharSequence columnQualifier, ColumnVisibility columnVisibility, long timestamp) Puts a deletion in this mutation.
byte[]	serialize()

Methods inherited from class java.lang.Object

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

Field Detail

EMPTY_BYTES

public static final byte[] EMPTY_BYTES

Constructor Detail

StoreMutation

public StoreMutation(byte[] row)

Creates a new mutation. A defensive copy is made.

Parameters:

row - row ID

StoreMutation

public StoreMutation(byte[] row,
                     int start,
                     int length)

Creates a new mutation. A defensive copy is made.

Parameters:

row - byte array containing row ID

start - starting index of row ID in byte array

length - length of row ID in byte array

Throws:

IndexOutOfBoundsException - if start or length is invalid

StoreMutation

public StoreMutation(byte[] row,
                     int start,
                     int length,
                     int initialBufferSize)

Creates a new mutation. A defensive copy is made.

Parameters:

row - byte array containing row ID

start - starting index of row ID in byte array

length - length of row ID in byte array

initialBufferSize - the initial size, in bytes, of the internal buffer for serializing

Throws:

IndexOutOfBoundsException - if start or length is invalid

StoreMutation

public StoreMutation()

Creates a new mutation.

StoreMutation

public StoreMutation(String rowId)

Creates a new mutation.

Parameters:

rowId - row ID

Method Detail

getRow

public byte[] getRow()

Gets the row ID for this mutation. Not a defensive copy.

Returns:

row ID

put

public void put(CharSequence columnFamily,
                CharSequence columnQualifier,
                byte[] value)

Puts a modification in this mutation. Column visibility is empty; timestamp is not set. All parameters are defensively copied.

Parameters:

columnFamily - column family

columnQualifier - column qualifier

value - cell value

put

public void put(CharSequence columnFamily,
                CharSequence columnQualifier,
                long timestamp,
                byte[] value)

Puts a modification in this mutation. Column visibility is empty. All appropriate parameters are defensively copied.

Parameters:

columnFamily - column family

columnQualifier - column qualifier

timestamp - timestamp

value - cell value

put

public void put(CharSequence columnFamily,
                CharSequence columnQualifier,
                ColumnVisibility columnVisibility,
                byte[] value)

Puts a modification in this mutation. Timestamp is not set. All parameters are defensively copied.

Parameters:

columnFamily - column family

columnQualifier - column qualifier

columnVisibility - column visibility

value - cell value

put

public void put(CharSequence columnFamily,
                CharSequence columnQualifier,
                ColumnVisibility columnVisibility,
                long timestamp,
                byte[] value)

Puts a modification in this mutation. Timestamp is not set. All parameters are defensively copied.

Parameters:

columnFamily - column family

columnQualifier - column qualifier

columnVisibility - column visibility

timestamp - timestamp

value - cell value

putDelete

public void putDelete(CharSequence columnFamily,
                      CharSequence columnQualifier)

Puts a deletion in this mutation. Timestamp is not set. All parameters are defensively copied.

Parameters:

columnFamily - column family

columnQualifier - column qualifier

putDelete

public void putDelete(CharSequence columnFamily,
                      CharSequence columnQualifier,
                      ColumnVisibility columnVisibility)

Puts a deletion in this mutation. Timestamp is not set. All parameters are defensively copied.

Parameters:

columnFamily - column family

columnQualifier - column qualifier

columnVisibility - column visibility

putDelete

public void putDelete(CharSequence columnFamily,
                      CharSequence columnQualifier,
                      ColumnVisibility columnVisibility,
                      long timestamp)

Puts a deletion in this mutation. All appropriate parameters are defensively copied.

Parameters:

columnFamily - column family

columnQualifier - column qualifier

columnVisibility - column visibility

timestamp - timestamp

put

public void put(CharSequence columnFamily,
                CharSequence columnQualifier,
                byte[] columnVisibility,
                boolean hasts,
                long timestamp,
                boolean deleted,
                byte[] value)

Puts a modification in this mutation. All appropriate parameters are defensively copied.

Parameters:

columnFamily - column family

columnQualifier - column qualifier

columnVisibility - column visibility

timestamp - timestamp

value - cell value

serialize

public byte[] serialize()

getUpdates

public List<StoreColumnUpdate> getUpdates()

Gets the modifications and deletions in this mutation. After calling this method, further modifications to this mutation are ignored. Changes made to the returned updates do not affect this mutation.

Returns:

list of modifications and deletions

newColumnUpdate

protected StoreColumnUpdate newColumnUpdate(byte[] cf,
                                            byte[] cq,
                                            byte[] cv,
                                            boolean hasts,
                                            long ts,
                                            boolean deleted,
                                            byte[] val)

encode

public static ByteBuffer encode(String string,
                                boolean replace)
                         throws CharacterCodingException

Converts the provided String to bytes using the UTF-8 encoding. If replace is true, then malformed input is replaced with the substitution character, which is U+FFFD. Otherwise the method throws a MalformedInputException.

Returns:

ByteBuffer: bytes stores at ByteBuffer.array() and length is ByteBuffer.limit()

Throws:

CharacterCodingException

getData

public byte[] getData()