Package com.yahoo.search.query.rewrite

Class RewriterUtils

  • public class RewriterUtils
extends Object
    Contains common utilities used by rewriters
    Author:
    Karen Sze Wing Lee

    • Constructor Detail

      • RewriterUtils

        public RewriterUtils()

    • Method Detail

      • loadFSA

        public static com.yahoo.fsa.FSA loadFSA​(File file,
                                        Query query)
                                 throws IOException
        Load FSA from file
        Parameters:
        file - FSA dictionary file object
        query - Query object from the searcher, could be null if not available
        Returns:
        FSA The FSA object for the input file path
        Throws:
        IOException

      • loadFSA

        public static com.yahoo.fsa.FSA loadFSA​(String filename,
                                        Query query)
                                 throws IOException
        Load FSA from file
        Parameters:
        filename - FSA dictionary file path
        query - Query object from the searcher, could be null if not available
        Returns:
        FSA The FSA object for the input file path
        Throws:
        IOException

      • getRewriteFromFSA

        public static String getRewriteFromFSA​(Query query,
                                       HashMap<String,​Object> rewriterDicts,
                                       String dictName,
                                       String key)
                                throws RuntimeException
        Retrieve rewrite from FSA given the original query
        Parameters:
        query - Query object from searcher
        dictName - FSA dictionary name
        rewriterDicts - list of rewriter dictionaries It has the following format: HashMap<dictionary name, FSA>
        key - The original query used to retrieve rewrite from the dictionary
        Returns:
        String The retrieved rewrites, null if query doesn't exist
        Throws:
        RuntimeException

      • getQPConfig

        public static String getQPConfig​(Query query,
                                 String rewriterName,
                                 String paramName)
        Get config parameter value set in query profile
        Parameters:
        query - Query object from the searcher
        rewriterName - Name of the rewriter
        paramName - parameter to be retrieved
        Returns:
        parameter value or null if not found

      • getRewriterChain

        public static String getRewriterChain​(Query query)
        Get rewriter chain value
        Parameters:
        query - Query object from the searcher
        Returns:
        parameter value or null if not found

      • getUserParam

        public static String getUserParam​(Query query,
                                  String paramName)
        Get user param value
        Parameters:
        query - Query object from the searcher
        paramName - parameter to be retrieved
        Returns:
        parameter value or null if not found

      • getRewriteMeta

        public static HashMap<String,​Object> getRewriteMeta​(Query query)
        Retrieve metadata passed by previous rewriter from query properties Initialize values if this is the first rewriter
        Parameters:
        query - Query object from the searcher
        Returns:
        hashmap containing the metadata

      • setRewriteMeta

        public static void setRewriteMeta​(Query query,
                                  HashMap<String,​Object> metadata)
        Pass metadata to the next rewriter through query properties
        Parameters:
        query - Query object from the searcher
        metadata - HashMap containing the metadata

      • getSpellCorrected

        public static String getSpellCorrected​(Query query,
                                       boolean qss_rw,
                                       boolean qss_sugg)
                                throws RuntimeException
        Retrieve spell corrected query with highest score from QLAS
        Parameters:
        query - Query object from the searcher
        qss_rw - Whether to consider qss_rw modification
        qss_sugg - Whether ot consider qss_sugg modification
        Returns:
        Spell corrected query or null if not found
        Throws:
        RuntimeException

      • getNormalizedOriginalQuery

        public static String getNormalizedOriginalQuery​(Query query)
        Retrieve normalized original query from query object
        Parameters:
        query - Query object from searcher
        Returns:
        normalized query

      • log

        public static void log​(Logger logger,
                       String msg)
        Log message
        Parameters:
        logger - Logger used for this msg
        msg - Log message

      • log

        public static void log​(Logger logger,
                       Query query,
                       String msg)
        Log message
        Parameters:
        logger - Logger used for this msg
        query - Query object from searcher
        msg - Log message

      • error

        public static void error​(Logger logger,
                         String msg)
        Print error message
        Parameters:
        logger - Logger used for this msg
        msg - Error message

      • error

        public static void error​(Logger logger,
                         Query query,
                         String msg)
        Print error message
        Parameters:
        logger - Logger used for this msg
        query - Query object from searcher
        msg - Error message