Assembly

An Assembly is a construction consisting of a chain of Transformer elements; each wired in pre- or post- operational mode. This chain is (always) terminated by one LoopbackTransformer element.

Once constructed, and correctly initialized, the bulk of the methods available on the Assembly are delegated to the head of the Transformer chain of the Assembly.

String DIRECTION

Variable

The name of a property in the attributes map that is passed to the init method, representing the assembly's desired wiring direction. The mapped value should be a valid Direction value. If this attribute is omitted, Direction.FORWARD is used.

boolean addPreTransformer (Transformer t)

Function

Adds the designated Transformer t, to the head of the current chain, and signals that it should operate in pre-processing mode; i.e. it should apply its internal transformation algorithm on the input data stream, before it passes that stream to the next element in the chain. Throws an IllegalArgumentException if the designated Transformer has a non-null tail; i.e. it is already an element of a chain.

boolean addPostTransformer (Transformer t)

Function

Adds the designated Transformer t, to the head of the current chain, and signals that it should operate in post-processing mode; i.e. it should apply its internal transformation algorithm on the input data stream, after it passes that stream to the next element in the chain. Throws an IllegalArgumentException if the designated Transformer has a non-null tail; i.e. it is already an element of a chain.

void init (java.util.Map attributes) throws TransformerException

Function

Initializes the Assembly for operation with specific characteristics, indicated by the designated attributes. The latter being a set of name-value pairs that describes the desired future behavior of this instance. Throws an IllegalStateException if the instance is already initialized.

void reset ()

Function

Resets the Assembly for re-initialization and use with other characteristics. This method always succeeds.

byte [] update (byte b) throws TransformerException

Function

Convenience method that calls the method with same name and three arguments, using a byte array of length 1 whose contents are the designated byte b. Returns the result of transformation. Throws an IllegalStateException if the instance is not yet initialized. Throws an TransformerException if a transformation-related exception occurs during the operation.

byte [] update (byte[] in) throws TransformerException

Function

Convenience method that calls the same method with three arguments. All bytes in in, starting from index position 0 are considered. Returns the result of transformation. Throws an IllegalStateException if the instance is not yet initialized. Throws a TransformerException if a transformation-related exception occurs during the operation.

byte [] update (byte[] in, int offset, int length) throws TransformerException

Function

Returns the result of processing a designated length bytes from a given in byte array, starting at position offset. Throws an IllegalStateException if the instance is not yet initialized. Throws an TransformerException if a transformation-related exception occurs during the operation.

byte [] lastUpdate () throws TransformerException

Function

Convenience method that calls the same method with three arguments. A zero-long byte array is used. Returns the result of transformation. Throws an IllegalStateException if the instance is not yet initialized. Throws an TransformerException if a transformation-related exception occurs during the operation.

byte [] lastUpdate (byte b) throws TransformerException

Function

Convenience method that calls the method with same name and three arguments, using a byte array of length 1 whose contents are the designated byte b. Returns the result of transformation. Throws an IllegalStateException if the instance is not yet initialized. Throws an TransformerException if a transformation-related exception occurs during the operation.

byte [] lastUpdate (byte[] in) throws TransformerException

Function

Convenience method that calls the same method with three arguments. All bytes in in, starting from index position 0 are considered. Returns the result of transformation. Throws an IllegalStateException if the instance is not yet initialized. Throws an TransformerException if a transformation-related exception occurs during the operation.

byte [] lastUpdate (byte[] in, int offset, int length) throws TransformerException

Function

Returns the result of processing a designated length bytes from the given in byte array, starting at index position offset and signals, at the same time, that this is the last push operation on this Transformer. Throws an IllegalStateException if the instance is not yet initialized. Throws an TransformerException if a transformation-related exception occurs during the operation.