org.apache.lens.server.api.query.save.param

Class ParameterParser

java.lang.Object

org.apache.lens.server.api.query.save.param.ParameterParser

public class ParameterParser
extends Object

Responsible for parsing the query (any grammar) and extracting parameters out of it

Constructor Summary

Constructors

Constructor and Description
ParameterParser(String query)

Method Summary

Methods

Modifier and Type	Method and Description
Set<String>	extractParameterNames() Returns set of parameter names found in the query
ParameterParserResponse	extractParameters() Returns parameter parser response for the query
static int	getParameterPrefixLength() Returns the length of the parameter prefix configured.
static String	getPatternStringFor(String baseParameterPattern)

Methods inherited from class java.lang.Object

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

Constructor Detail

ParameterParser

public ParameterParser(String query)

Method Detail

getPatternStringFor

public static String getPatternStringFor(String baseParameterPattern)

Parameters:

baseParameterPattern, - regex denoting the parameters to match

Returns:

a regex pattern that captures the valid occurrences in the 1st group while ignoring occurrences inside literals (single/double quoted) To search for a parameter named p1, we will have to search for ':p1' that occurs natively in the query ignoring the ones that are single/double quoted. For eg. In the string - "Hai this is valid param :p1 and 'this is invalid param :p1'", the first occurrence is valid and the second is invalid as it falls under matching single quotes invalid_pattern_1|invalid_pattern_2|PARAMETER_INDICATOR_PREFIX(baseParameterPattern) For a baseParameterPattern - param1, the resulting pattern would be '[^']*'|"[^"]*"|:(param1)

getParameterPrefixLength

public static int getParameterPrefixLength()

Returns the length of the parameter prefix configured.

Returns:

length of the parameter prefix

extractParameterNames

public Set<String> extractParameterNames()

Returns set of parameter names found in the query

Returns:

set of parameter names

extractParameters

public ParameterParserResponse extractParameters()

Returns parameter parser response for the query

Returns:

ParameterParserResponse object