org.gcube.indexmanagement.bdbwrapper
Class BDBWrapper

java.lang.Object
  org.gcube.indexmanagement.bdbwrapper.BDBWrapper

All Implemented Interfaces:

ForwardIndex

public class BDBWrapper
extends Object
implements ForwardIndex

Class to store key and value pairs in the berkeley database

Field Summary

static String	EXACT
static String[]	SupportedRelations
static String	WITHIN

Constructor Summary

BDBWrapper(String baseDir, String dbName, String resourceId, String[] keyNames, ForwardIndexType[] dbT)
Provides the ability to store simple key-value pairs.

Method Summary

void	close() Closes this BDBWrapper by deleting the whole index
protected void	finalize()
String	getAllDec(String keyName, ResultType resType) Gets all.
String	getAllInc(String keyName, ResultType resType) Gets all.
String	getEQ(String keyName, Object key, ResultType resType) Gets the values where the key equals the input key.
String	getGE(String keyName, Object keyGE, ResultType resType) Gets values >= keyGE.
String	getGEandLE(String keyName, Object keyGE, Object keyLE, ResultType resType) Gets keyGE <= values <= keyLE
String	getGEandLT(String keyName, Object keyGE, Object keyLT, ResultType resType) Gets keyGE <= values < keyLT
String	getGT(String keyName, Object keyGT, ResultType resType) Gets keyGT < values
String	getGTandLE(String keyName, Object keyGT, Object keyLE, ResultType resType) Gets keyGT < values <= keyLE
String	getGTandLT(String keyName, Object keyGT, Object keyLT, ResultType resType) Gets keyGT < values < keyLT
String	getLE(String keyName, Object keyLE, ResultType resType) Gets values <= keyLE
String	getLT(String keyName, Object keyLT, ResultType resType) Gets values < keyLT
int	getNumDocs() Returns the number of stored documents(values)
int[]	getNumKeys() Returns the number of entries for each indexed field
long	getPackageSize() Returns the package size that determines how keys and values are multiplexed.
static ArrayList<String>	getPresentableFromXML(String fieldsString, String colID, String colLang) Parses the XML containing the presentable information for a document (FORMAT: fieldvalue ) and returns an array containing the unique field names.
static HashMap<String,String>	getPresentationFieldsFromXML(String fieldsString) Parses the XML containing the presentable information for a document (FORMAT: fieldvalue ) and returns a map containing the field name - value pairs.
void	mergeAddition(File inputIndex) Receives the file with rowsets that is to be merged into the index.
int	mergeDeletion(File deletionFile) THIS METHOD IS NEVER CALLED IN FORWARD INDEX.
URI	processQuery(String cqlQuery, ArrayList<String> presentable, ArrayList<String> searchable, RRadaptor adaptor)
void	setPackageSize(long packageSize) Sets the package size that determines how keys and values are multiplexed.
void	updateIndex() Updates the index.

Methods inherited from class java.lang.Object

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

Field Detail

EXACT

public static final String EXACT

See Also:

Constant Field Values

WITHIN

public static final String WITHIN

See Also:

Constant Field Values

SupportedRelations

public static String[] SupportedRelations

Constructor Detail

BDBWrapper

public BDBWrapper(String baseDir,
                  String dbName,
                  String resourceId,
                  String[] keyNames,
                  ForwardIndexType[] dbT)
           throws IndexException

Provides the ability to store simple key-value pairs.

Parameters:

baseDir - The base directory - it must exist before the call to the constructor

dbName - The name of the database to be used

resourceId - The ID of the collection to be indexed

keyNames - The names of the keys. One index is created for each keyName

dbT - The corresponding type of each keyName(int,string or float,string or string,string date,string).

Throws:

IndexException - - in case of failure.

Method Detail

getNumDocs

public int getNumDocs()

Returns the number of stored documents(values)

Returns:

the number of stored documents

getNumKeys

public int[] getNumKeys()

Returns the number of entries for each indexed field

Returns:

array with the number of entries for each indexed field

getPackageSize

public long getPackageSize()

Returns the package size that determines how keys and values are multiplexed. Package size refers to how many key values will be sent before the corresponding values are sent.

Returns:

package size

setPackageSize

public void setPackageSize(long packageSize)

Sets the package size that determines how keys and values are multiplexed. Package size refers to how many key values will be sent before the corresponding values are sent.

Parameters:

packageSize - - package size

close

public void close()
           throws Exception

Closes this BDBWrapper by deleting the whole index

Throws:

Exception

finalize

protected void finalize()
                 throws Throwable

Overrides:

finalize in class Object

Throws:

Throwable

getEQ

public String getEQ(String keyName,
                    Object key,
                    ResultType resType)
             throws IndexException

Gets the values where the key equals the input key.

Specified by:

getEQ in interface ForwardIndex

Parameters:

key - - The equality key for the search

bKeysOnly - return only keys, or full tuples?

Returns:

String - The EPR of the result set containing the result.

Throws:

IndexException - - when IOException is received.

getGE

public String getGE(String keyName,
                    Object keyGE,
                    ResultType resType)
             throws IndexException

Gets values >= keyGE.

Specified by:

getGE in interface ForwardIndex

Parameters:

keyGE - - the key

bKeysOnly - return only keys, or full tuples?

Returns:

String - The EPR of the result set containing the result.

Throws:

IndexException - - when IOException is received.

getGT

public String getGT(String keyName,
                    Object keyGT,
                    ResultType resType)
             throws IndexException

Gets keyGT < values

Specified by:

getGT in interface ForwardIndex

Parameters:

keyGT - - The lower exclusive bound key

bKeysOnly - return only keys, or full tuples?

Returns:

String - The EPR of the result set containing the result.

Throws:

IndexException - - when IOException is received.

getLE

public String getLE(String keyName,
                    Object keyLE,
                    ResultType resType)
             throws IndexException

Gets values <= keyLE

Specified by:

getLE in interface ForwardIndex

Parameters:

keyLE - - The upper inclusive bound key

bKeysOnly - return only keys, or full tuples?

Returns:

String - The EPR of the result set containing the result.

Throws:

IndexException - - when IOException is received.

getLT

public String getLT(String keyName,
                    Object keyLT,
                    ResultType resType)
             throws IndexException

Gets values < keyLT

Specified by:

getLT in interface ForwardIndex

Parameters:

keyLT - - The upper exclusive bound key

bKeysOnly - return only keys, or full tuples?

Returns:

String - The EPR of the result set containing the result.

Throws:

IndexException - - when IOException is received.

getGEandLE

public String getGEandLE(String keyName,
                         Object keyGE,
                         Object keyLE,
                         ResultType resType)
                  throws IndexException

Gets keyGE <= values <= keyLE

Specified by:

getGEandLE in interface ForwardIndex

Parameters:

keyGE - - The lower inclusive bound

keyLE - - The upper inclusive bound

bKeysOnly - return only keys, or full tuples?

Returns:

String - The EPR of the result set containing the result.

Throws:

IndexException - - when IOException is received.

getGEandLT

public String getGEandLT(String keyName,
                         Object keyGE,
                         Object keyLT,
                         ResultType resType)
                  throws IndexException

Gets keyGE <= values < keyLT

Specified by:

getGEandLT in interface ForwardIndex

Parameters:

keyGE - - The lower inclusive bound key

keyLT - - The upper exclusive bound key

bKeysOnly - return only keys, or full tuples?

Returns:

String - The EPR of the result set containing the result.

Throws:

IndexException - - when IOException is received.

getGTandLE

public String getGTandLE(String keyName,
                         Object keyGT,
                         Object keyLE,
                         ResultType resType)
                  throws IndexException

Gets keyGT < values <= keyLE

Specified by:

getGTandLE in interface ForwardIndex

Parameters:

keyGT - - The lower exclusive bound

keyLE - - The upper inclusive bound

bKeysOnly - return only keys, or full tuples?

Returns:

String - The EPR of the result set containing the result.

Throws:

IndexException - - when IOException is received.

getGTandLT

public String getGTandLT(String keyName,
                         Object keyGT,
                         Object keyLT,
                         ResultType resType)
                  throws IndexException

Gets keyGT < values < keyLT

Specified by:

getGTandLT in interface ForwardIndex

Parameters:

keyGT - - The lower exclusive bound key

keyLT - - The upper exclusive bound key

bKeysOnly - return only keys, or full tuples?

Returns:

String - The EPR of the result set containing the result.

Throws:

IndexException - - when IOException is received.

getAllDec

public String getAllDec(String keyName,
                        ResultType resType)
                 throws IndexException

Gets all.

Parameters:

bKeysOnly - return only keys, or full tuples?

Returns:

String - The EPR of the result set containing the result.

Throws:

IndexException - - when IOException is received.

getAllInc

public String getAllInc(String keyName,
                        ResultType resType)
                 throws IndexException

Gets all.

Parameters:

bKeysOnly - return only keys, or full tuples?

Returns:

String - The EPR of the result set containing the result.

Throws:

IndexException - - when IOException is received.

processQuery

public URI processQuery(String cqlQuery,
                        ArrayList<String> presentable,
                        ArrayList<String> searchable,
                        RRadaptor adaptor)
                 throws gr.uoa.di.madgik.grs.writer.GRS2WriterException

Throws:

gr.uoa.di.madgik.grs.writer.GRS2WriterException

mergeDeletion

public int mergeDeletion(File deletionFile)
                  throws IndexException

THIS METHOD IS NEVER CALLED IN FORWARD INDEX. Merge deletion is used to update the index with documents to be deleted.

Parameters:

deletionFile - - the file with the content to delete .

Throws:

IndexException - - in case of failure.

mergeAddition

public void mergeAddition(File inputIndex)
                   throws IndexException

Receives the file with rowsets that is to be merged into the index.

Parameters:

inputIndex - - The file with rowsets that is merged into the index.

Throws:

IndexException - - in case of error.

getPresentationFieldsFromXML

public static HashMap<String,String> getPresentationFieldsFromXML(String fieldsString)

Parses the XML containing the presentable information for a document (FORMAT: fieldvalue ) and returns a map containing the field name - value pairs.

Parameters:

fieldsString - - XML containing the presentable information for a document

Returns:

HashMap containing the field pairs

getPresentableFromXML

public static ArrayList<String> getPresentableFromXML(String fieldsString,
                                                      String colID,
                                                      String colLang)

Parses the XML containing the presentable information for a document (FORMAT: fieldvalue ) and returns an array containing the unique field names.

Parameters:

fieldsString - - XML containing the presentable information for a document

Returns:

ArrayList containing the unique field names

updateIndex

public void updateIndex()
                 throws IndexException

Updates the index. NOT USED IN THE FORWARDINDEX

Throws:

IndexException - - in case of error