HbaseObjectWritableFor96Migration (Apache HBase 1.2.12 API)

java.lang.Object
- org.apache.hadoop.hbase.security.access.HbaseObjectWritableFor96Migration

All Implemented Interfaces:

org.apache.hadoop.conf.Configurable, WritableWithSize, org.apache.hadoop.io.Writable

Deprecated.
This class is needed migrating TablePermissions written with Writables. It is needed to read old permissions written pre-0.96. This class is to be removed after HBase 0.96 ships since then all permissions will have been migrated and written with protobufs.
```
@Deprecated
@InterfaceAudience.Private
 class HbaseObjectWritableFor96Migration
extends Object
implements org.apache.hadoop.io.Writable, WritableWithSize, org.apache.hadoop.conf.Configurable
```
This is a customized version of the polymorphic hadoop ObjectWritable. It removes UTF8 (HADOOP-414). Using Text intead of UTF-8 saves ~2% CPU between reading and writing objects running a short sequentialWrite Performance Evaluation test just in ObjectWritable alone; more when we're doing randomRead-ing. Other optimizations include our passing codes for classes instead of the actual class names themselves. This makes it so this class needs amendment if non-Writable classes are introduced -- if passed a Writable for which we have no code, we just do the old-school passing of the class name, etc. -- but passing codes the savings are large particularly when cell data is small (If < a couple of kilobytes, the encoding/decoding of class name and reflection to instantiate class was costing in excess of the cell handling).

Nested Class Summary

Nested Classes
Modifier and Type Class and Description

private static class HbaseObjectWritableFor96Migration.NullInstance
Deprecated.

Nested Classes
Modifier and Type	Class and Description
`private static class`	`HbaseObjectWritableFor96Migration.NullInstance` Deprecated.

Field Summary

Fields
Modifier and Type	Field and Description
`(package private) static Map<Class<?>,Integer>`	`CLASS_TO_CODE` Deprecated.
`(package private) static Map<Integer,Class<?>>`	`CODE_TO_CLASS` Deprecated.
`private org.apache.hadoop.conf.Configuration`	`conf` Deprecated.
`private Class<?>`	`declaredClass` Deprecated.
`private static int`	`GENERIC_ARRAY_CODE` Deprecated.
`private Object`	`instance` Deprecated.
`private static org.apache.commons.logging.Log`	`LOG` Deprecated.
`private static int`	`NEXT_CLASS_CODE` Deprecated.
`private static byte`	`NOT_ENCODED` Deprecated.

Constructor Summary

Constructors
Constructor and Description
`HbaseObjectWritableFor96Migration()` Deprecated. default constructor for writable
`HbaseObjectWritableFor96Migration(Class<?> declaredClass, Object instance)` Deprecated.
`HbaseObjectWritableFor96Migration(Object instance)` Deprecated.

Method Summary

Methods
Modifier and Type	Method and Description
`private static void`	`addToMap(Class<?> clazz, int code)` Deprecated.
`(package private) Object`	`get()` Deprecated.
`private static Class`	`getClassByName(org.apache.hadoop.conf.Configuration conf, String className)` Deprecated.
`(package private) static Integer`	`getClassCode(Class<?> c)` Deprecated.
`org.apache.hadoop.conf.Configuration`	`getConf()` Deprecated.
`(package private) Class<?>`	`getDeclaredClass()` Deprecated.
`(package private) static int`	`getNextClassCode()` Deprecated.
`(package private) static Method`	`getStaticProtobufMethod(Class<?> declaredClass, String method, Class<?>... args)` Deprecated.
`long`	`getWritableSize()` Deprecated. Provide a size hint to the caller.
`(package private) static long`	`getWritableSize(Object instance, Class declaredClass, org.apache.hadoop.conf.Configuration conf)` Deprecated.
`(package private) static Class<?>`	`readClass(org.apache.hadoop.conf.Configuration conf, DataInput in)` Deprecated. Reads and returns the class as written by `writeClass(DataOutput, Class)`
`void`	`readFields(DataInput in)` Deprecated.
`(package private) static Object`	`readObject(DataInput in, org.apache.hadoop.conf.Configuration conf)` Deprecated. Read a `Writable`, `String`, primitive type, or an array of the preceding.
`(package private) static Object`	`readObject(DataInput in, HbaseObjectWritableFor96Migration objectWritable, org.apache.hadoop.conf.Configuration conf)` Deprecated. Read a `Writable`, `String`, primitive type, or an array of the preceding.
`(package private) void`	`set(Object instance)` Deprecated. Reset the instance.
`void`	`setConf(org.apache.hadoop.conf.Configuration conf)` Deprecated.
`String`	`toString()` Deprecated.
`(package private) static com.google.protobuf.Message`	`tryInstantiateProtobuf(Class<?> protoClass, DataInput dataIn)` Deprecated. Try to instantiate a protocol buffer of the given message class from the given input stream.
`void`	`write(DataOutput out)` Deprecated.
`(package private) static void`	`writeClass(DataOutput out, Class<?> c)` Deprecated. Writes the encoded class code as defined in CLASS_TO_CODE, or the whole class name if not defined in the mapping.
`(package private) static void`	`writeClassCode(DataOutput out, Class<?> c)` Deprecated. Write out the code for passed Class.
`(package private) static void`	`writeObject(DataOutput out, Object instance, Class declaredClass, org.apache.hadoop.conf.Configuration conf)` Deprecated. Write a `Writable`, `String`, primitive type, or an array of the preceding.

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

Field Detail

LOG

private static final org.apache.commons.logging.Log LOG

Deprecated.

CODE_TO_CLASS

static final Map<Integer,Class<?>> CODE_TO_CLASS

Deprecated.

CLASS_TO_CODE

static final Map<Class<?>,Integer> CLASS_TO_CODE

Deprecated.

NOT_ENCODED
```
private static final byte NOT_ENCODED
```
Deprecated.

See Also:
Constant Field Values

GENERIC_ARRAY_CODE

private static final int GENERIC_ARRAY_CODE

Deprecated.

NEXT_CLASS_CODE

private static final int NEXT_CLASS_CODE

Deprecated.

declaredClass
```
private Class<?> declaredClass
```
Deprecated.

instance
```
private Object instance
```
Deprecated.

conf

private org.apache.hadoop.conf.Configuration conf

Deprecated.

Constructor Detail
- HbaseObjectWritableFor96Migration
```
HbaseObjectWritableFor96Migration()
```
  Deprecated.
  
  default constructor for writable
- HbaseObjectWritableFor96Migration
```
HbaseObjectWritableFor96Migration(Object instance)
```
  Deprecated.
  
  Parameters:
  instance -
- HbaseObjectWritableFor96Migration
```
HbaseObjectWritableFor96Migration(Class<?> declaredClass,
                                 Object instance)
```
  Deprecated.
  
  Parameters:
  declaredClass -
  instance -

Method Detail

get
```
Object get()
```
Deprecated.

Returns:
the instance, or null if none.

getDeclaredClass
```
Class<?> getDeclaredClass()
```
Deprecated.

Returns:
the class this is meant to be.

set
```
void set(Object instance)
```
Deprecated.

Reset the instance.

Parameters:
instance -

toString
```
public String toString()
```
Deprecated.

Overrides:

toString in class Object

See Also:
Object.toString()

readFields
```
public void readFields(DataInput in)
                throws IOException
```
Deprecated.

Specified by:

readFields in interface org.apache.hadoop.io.Writable

Throws:

IOException

write
```
public void write(DataOutput out)
           throws IOException
```
Deprecated.

Specified by:

write in interface org.apache.hadoop.io.Writable

Throws:

IOException

getWritableSize
```
public long getWritableSize()
```
Deprecated.

Description copied from interface: WritableWithSize

Provide a size hint to the caller. write() should ideally not go beyond this if at all possible. You can return 0 if there is no size hint.

Specified by:

getWritableSize in interface WritableWithSize

Returns:
the size of the writable

getClassCode

static Integer getClassCode(Class<?> c)
                     throws IOException

Deprecated.

Throws:: IOException

getNextClassCode
```
static int getNextClassCode()
```
Deprecated.

Returns:
the next object code in the list. Used in testing to verify that additional fields are not added

writeClassCode

static void writeClassCode(DataOutput out,
                  Class<?> c)
                    throws IOException

Deprecated.

Write out the code for passed Class.

Parameters:: out -; c -
Throws:: IOException

getWritableSize

static long getWritableSize(Object instance,
                   Class declaredClass,
                   org.apache.hadoop.conf.Configuration conf)

Deprecated.

writeObject

static void writeObject(DataOutput out,
               Object instance,
               Class declaredClass,
               org.apache.hadoop.conf.Configuration conf)
                 throws IOException

Deprecated.

Write a Writable, String, primitive type, or an array of the preceding.

Parameters:: out -; instance -; declaredClass -; conf -
Throws:: IOException

writeClass
```
static void writeClass(DataOutput out,
              Class<?> c)
                throws IOException
```
Deprecated.

Writes the encoded class code as defined in CLASS_TO_CODE, or the whole class name if not defined in the mapping.

Throws:

IOException

readClass

static Class<?> readClass(org.apache.hadoop.conf.Configuration conf,
                 DataInput in)
                   throws IOException

Deprecated.

Reads and returns the class as written by writeClass(DataOutput, Class)

Throws:: IOException

readObject

static Object readObject(DataInput in,
                org.apache.hadoop.conf.Configuration conf)
                  throws IOException

Deprecated.

Read a Writable, String, primitive type, or an array of the preceding.

Parameters:: in -; conf -
Returns:: the object
Throws:: IOException

readObject

static Object readObject(DataInput in,
                HbaseObjectWritableFor96Migration objectWritable,
                org.apache.hadoop.conf.Configuration conf)
                  throws IOException

Deprecated.

Read a Writable, String, primitive type, or an array of the preceding.

Parameters:: in -; objectWritable -; conf -
Returns:: the object
Throws:: IOException

tryInstantiateProtobuf
```
static com.google.protobuf.Message tryInstantiateProtobuf(Class<?> protoClass,
                                                 DataInput dataIn)
                                                   throws IOException
```
Deprecated.

Try to instantiate a protocol buffer of the given message class from the given input stream.

Parameters:
protoClass - the class of the generated protocol buffer
dataIn - the input stream to read from

Returns:
the instantiated Message instance

Throws:

IOException - if an IO problem occurs

getStaticProtobufMethod

static Method getStaticProtobufMethod(Class<?> declaredClass,
                             String method,
                             Class<?>... args)

Deprecated.

getClassByName

private static Class getClassByName(org.apache.hadoop.conf.Configuration conf,
                   String className)
                             throws ClassNotFoundException

Deprecated.

Throws:: ClassNotFoundException

addToMap

private static void addToMap(Class<?> clazz,
            int code)

Deprecated.

setConf
```
public void setConf(org.apache.hadoop.conf.Configuration conf)
```
Deprecated.

Specified by:

setConf in interface org.apache.hadoop.conf.Configurable

getConf
```
public org.apache.hadoop.conf.Configuration getConf()
```
Deprecated.

Specified by:

getConf in interface org.apache.hadoop.conf.Configurable

Class HbaseObjectWritableFor96Migration

Nested Class Summary

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

LOG

CODE_TO_CLASS

CLASS_TO_CODE

NOT_ENCODED

GENERIC_ARRAY_CODE

NEXT_CLASS_CODE

declaredClass

instance

conf

Constructor Detail

HbaseObjectWritableFor96Migration

HbaseObjectWritableFor96Migration

HbaseObjectWritableFor96Migration

Method Detail

get

getDeclaredClass

set

toString

readFields

write

getWritableSize

getClassCode

getNextClassCode

writeClassCode

getWritableSize

writeObject

writeClass

readClass

readObject

readObject

tryInstantiateProtobuf

getStaticProtobufMethod

getClassByName

addToMap

setConf

getConf