org.datavec.api.writable

Class WritableFactory

java.lang.Object

org.datavec.api.writable.WritableFactory

public class WritableFactory
extends Object

Factory class for creating and saving writable objects to/from DataInput and DataOutput

Author:

Alex Black

Method Summary

Modifier and Type	Method and Description
static WritableFactory	getInstance()
Writable	newWritable(short writableTypeKey) Create a new writable instance (using reflection) given the specified key
Writable	readWithType(DataInput dataInput) Read a Writable From the DataInput, where the Writable was previously written using writeWithType(Writable, DataOutput)
void	registerWritableType(short writableTypeKey, Class<? extends Writable> writableClass) Register a writable class with a specific key (as a short).
void	writeWithType(Writable w, DataOutput dataOutput) A convenience method for writing a given Writable object to a DataOutput.

Methods inherited from class java.lang.Object

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

Method Detail

getInstance

public static WritableFactory getInstance()

Returns:

Singleton WritableFactory instance

registerWritableType

public void registerWritableType(short writableTypeKey,
                                 @NonNull
                                 Class<? extends Writable> writableClass)

Register a writable class with a specific key (as a short). Note that key values must be unique for each type of Writable, as they are used as type information in certain types of serialisation. Consequently, an exception will be thrown If the key value is not unique or is already assigned.
Note that in general, this method needs to only be used for custom Writable types; Care should be taken to ensure that the given key does not change once assigned.

Parameters:

writableTypeKey - Key for the Writable

writableClass - Class for the given key. Must have a no-arg constructor

newWritable

public Writable newWritable(short writableTypeKey)

Create a new writable instance (using reflection) given the specified key

Parameters:

writableTypeKey - Key to create a new writable instance for

Returns:

A new (empty/default) Writable instance

writeWithType

public void writeWithType(Writable w,
                          DataOutput dataOutput)
                   throws IOException

A convenience method for writing a given Writable object to a DataOutput. The key is 1st written (a single short) followed by the value from writable.

Parameters:

w - Writable value

dataOutput - DataOutput to write both key and value to

Throws:

IOException - If an error occurs during writing to the DataOutput

readWithType

public Writable readWithType(DataInput dataInput)
                      throws IOException

Read a Writable From the DataInput, where the Writable was previously written using writeWithType(Writable, DataOutput)

Parameters:

dataInput - DataInput to read the Writable from

Returns:

Writable from the DataInput

Throws:

IOException - In an error occurs during reading