com.denodo.parser.connection.filter

Class ConnectionFilter

java.lang.Object

com.denodo.parser.connection.filter.ConnectionFilter

Direct Known Subclasses:

CustomConnectionFilter

public abstract class ConnectionFilter
extends Object

Parent class of all the connection filters. To develop a custom connection filter do not override this class. Instead, override CustomConnectionFilter.

Field Summary

Fields

Modifier and Type	Field and Description
protected ConnectionFilter	nextFilter
protected HashMap<String,Object>	parameters

Constructor Summary

Constructors

Constructor and Description
ConnectionFilter()

Method Summary

Modifier and Type	Method and Description
InputStream	doFilter(InputStream in)
protected abstract InputStream	execute(InputStream inputStream) The Execution Engine invokes this method every time a query involves a base view of the data source that has this filter assigned.
ConnectionFilter	getNextFilter()
HashMap<String,Object>	getParameters() Returns the input parameters of the filter.
abstract String	getVQLName()
void	setNextFilter(ConnectionFilter nextFilter)
void	setParameters(HashMap<String,Object> parameters)

Methods inherited from class java.lang.Object

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

Field Detail

nextFilter

protected ConnectionFilter nextFilter

parameters

protected HashMap<String,Object> parameters

Constructor Detail

ConnectionFilter

public ConnectionFilter()

Method Detail

setNextFilter

public final void setNextFilter(ConnectionFilter nextFilter)

getNextFilter

public final ConnectionFilter getNextFilter()

setParameters

public final void setParameters(HashMap<String,Object> parameters)

getParameters

public final HashMap<String,Object> getParameters()

Returns the input parameters of the filter.

Returns:

the input parameters.

doFilter

public final InputStream doFilter(InputStream in)
                           throws com.denodo.util.exceptions.InternalErrorException

Throws:

com.denodo.util.exceptions.InternalErrorException

execute

protected abstract InputStream execute(InputStream inputStream)
                                throws com.denodo.util.exceptions.InternalErrorException

The Execution Engine invokes this method every time a query involves a base view of the data source that has this filter assigned.

In this method you have to read the data of the InputStream parameter and return another InputStream with the data transformed.

Parameters:

inputStream - an InputStream that provides the data from the source.

Returns:

an InputStream that returns the data transformed by the filter.

Throws:

com.denodo.util.exceptions.InternalErrorException - Throw this exception if there is an error during the execution of the filter. The Execution Engine will capture the exception and interrupt the access to the source and the execution of the filter.

getVQLName

public abstract String getVQLName()