gov.nasa.pds.transport

Class AbstractPdsGetHandler

java.lang.Object

gov.nasa.pds.transport.AbstractPdsGetHandler

All Implemented Interfaces:

org.apache.oodt.product.handlers.ofsn.metadata.OFSNMetKeys, org.apache.oodt.product.handlers.ofsn.OFSNGetHandler

Direct Known Subclasses:

PdsLabelHandler, PdsLabelTransformerHandler, ZipDirHandler, ZipFileHandler, ZipSizeDirHandler, ZipSizeFileHandler

public abstract class AbstractPdsGetHandler
extends Object
implements org.apache.oodt.product.handlers.ofsn.OFSNGetHandler, org.apache.oodt.product.handlers.ofsn.metadata.OFSNMetKeys

Abstract superclass of OFSN handlers that generate PDS products. Each subclass should: 1) define the mime type of the output file it generates, specified in the handler XML configuration 2) implement the specific process to generate the output file from the input file in the method getOutputFile()

Author:

Luca Cinquini

Field Summary

Fields

Modifier and Type	Field and Description
protected static Logger	LOG

Fields inherited from interface org.apache.oodt.product.handlers.ofsn.metadata.OFSNMetKeys

GET_CMD, LISTING_CMD, OFSN_COMPUTE_DIR_SIZE, OFSN_COMPUTE_FILE_SIZE, OFSN_XML_CONF_FILE_KEY

Constructor Summary

Constructors

Constructor and Description
AbstractPdsGetHandler()

Method Summary

Methods

Modifier and Type	Method and Description
void	configure(Properties properties) Configuration method sets the temporary cache directory.
protected File	getCache() Returns the directory where products are created.
protected org.apache.oodt.product.handlers.ofsn.OFSNFileHandlerConfiguration	getConfiguration() Returns the overall configuration read from file 'ofsn-ps.xml'.
protected abstract File	getOutputFile(String inputFilePath) Method to generate the requested product from the given target.
byte[]	retrieveChunk(String inputFilePath, long offset, int length) Method that returns the generated product, piece by piece.
long	sizeOf(String inputFilePath) Method to establish the size of the product to be returned.

Methods inherited from class java.lang.Object

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

Field Detail

LOG

protected static final Logger LOG

Constructor Detail

AbstractPdsGetHandler

public AbstractPdsGetHandler()

Method Detail

configure

public void configure(Properties properties)

Configuration method sets the temporary cache directory. Overriding subclasses should also invoke this superclass method.

Specified by:

configure in interface org.apache.oodt.product.handlers.ofsn.OFSNGetHandler

retrieveChunk

public byte[] retrieveChunk(String inputFilePath,
                   long offset,
                   int length)
                     throws org.apache.oodt.product.ProductException

Method that returns the generated product, piece by piece. Invoked after the size of the product has been determined.

Specified by:

retrieveChunk in interface org.apache.oodt.product.handlers.ofsn.OFSNGetHandler

Throws:

org.apache.oodt.product.ProductException

sizeOf

public long sizeOf(String inputFilePath)

Method to establish the size of the product to be returned. This method implicitly triggers the creation of the product.

Specified by:

sizeOf in interface org.apache.oodt.product.handlers.ofsn.OFSNGetHandler

getCache

protected File getCache()

Returns the directory where products are created.

Returns:

getConfiguration

protected org.apache.oodt.product.handlers.ofsn.OFSNFileHandlerConfiguration getConfiguration()

Returns the overall configuration read from file 'ofsn-ps.xml'.

Returns:

getOutputFile

protected abstract File getOutputFile(String inputFilePath)
                               throws org.apache.oodt.product.ProductException

Method to generate the requested product from the given target. Must be implemented by subclasses.

Parameters:

inputFile -

Returns:

outputFile

Throws:

org.apache.oodt.product.ProductException