Package com.yahoo.search.query.rewrite.rewriters

Class MisspellRewriter

  • All Implemented Interfaces:
    com.yahoo.component.Component, com.yahoo.component.Deconstructable, java.lang.Comparable<com.yahoo.component.Component>
    public class MisspellRewriter
extends QueryRewriteSearcher
    This rewriter would retrieve spell corrected query from QLAS and add it to the original query tree as equiv
    - Features:
    RewritesAsEquiv flag: add rewrites to original query as equiv
    Author:
    Karen Sze Wing Lee

    • Field Summary

      Fields 
      Modifier and Type Field Description
      static java.lang.String REWRITER_NAME  

      • Fields inherited from class com.yahoo.component.AbstractComponent

        isDeconstructable

    • Constructor Summary

      Constructors 
      Constructor Description
      MisspellRewriter()
      Constructor for MisspellRewriter unit test
      MisspellRewriter​(com.yahoo.component.ComponentId id)
      Constructor for MisspellRewriter

    • Method Summary

      All Methods Instance Methods Concrete Methods 
      Modifier and Type Method Description
      boolean configure​(com.yahoo.filedistribution.fileacquirer.FileAcquirer fileAcquirer, RewritesConfig config, java.util.HashMap<java.lang.String,​java.io.File> fileList)
      Instance creation time config loading besides FSA.
      java.util.HashMap<java.lang.String,​java.lang.String> getDefaultFSAs()
      Get default FSA dictionary names
      java.lang.String getRewriterName()
      Get the name of the rewriter
      boolean getSkipRewriterIfRewritten()
      Get the flag which specifies whether this rewriter should be skipped if the query has been rewritten
      java.util.HashMap<java.lang.String,​java.lang.Object> rewrite​(Query query, java.lang.String dictKey)
      Main logic of rewriter
      - Retrieve spell corrected query from QLAS
      - Add spell corrected query as equiv

      • Methods inherited from class com.yahoo.component.chain.ChainedComponent

        getAnnotatedDependencies, getDefaultAnnotatedDependencies, getDependencies, initDependencies

      • Methods inherited from class com.yahoo.component.AbstractComponent

        clone, compareTo, deconstruct, getClassName, getId, getIdString, hasInitializedId, initId, isDeconstructable, setIsDeconstructable

      • Methods inherited from class java.lang.Object

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

    • Constructor Detail

      • MisspellRewriter

        @Inject
public MisspellRewriter​(com.yahoo.component.ComponentId id)
        Constructor for MisspellRewriter

      • MisspellRewriter

        public MisspellRewriter()
        Constructor for MisspellRewriter unit test

    • Method Detail

      • configure

        public boolean configure​(com.yahoo.filedistribution.fileacquirer.FileAcquirer fileAcquirer,
                         RewritesConfig config,
                         java.util.HashMap<java.lang.String,​java.io.File> fileList)
        Instance creation time config loading besides FSA. Empty for this rewriter
        Specified by:
        configure in class QueryRewriteSearcher
        Parameters:
        fileAcquirer - Required param for retrieving file type config (see vespa's search container doc for more detail)
        config - Config from vespa-services.xml (see vespa's search container doc for more detail)
        fileList - pairs of file name and file handler for unit tests
        Returns:
        boolean true if loaded successfully, false otherwise

      • rewrite

        public java.util.HashMap<java.lang.String,​java.lang.Object> rewrite​(Query query,
                                                                          java.lang.String dictKey)
                                                                   throws java.lang.RuntimeException
        Main logic of rewriter
        - Retrieve spell corrected query from QLAS
        - Add spell corrected query as equiv
        Specified by:
        rewrite in class QueryRewriteSearcher
        Parameters:
        query - Query object from searcher
        dictKey - the key passed from previous rewriter to be treated as "original query from user" For example, if previous is misspell rewriter, it would pass the corrected query as the "original query from user". For other rewriters which add variants, abbr, etc to the query, the original query should be passed as a key. This rewriter could still choose to ignore this key. This key is not the rewritten query itself. For example, if original query is (willl smith) and the rewritten query is (willl smith) OR (will smith) the key to be passed could be (will smith)
        Returns:
        HashMap which contains the key value pairs:
        - whether this query has been rewritten by this rewriter
        key: rewritten
        value: true or false
        - the key to be treated as "original query from user" in next rewriter downstream, for example, misspell rewriter would pass the corrected query as the "original query from user" to the next rewriter. For other rewriters which add variants, abbr, etc to the query, the original query should be passed as a key. This key is not necessarily consumed by the next rewriter. The next rewriter can still choose to ignore this key.
        key: newDictKey
        value: new dict key
        Throws:
        java.lang.RuntimeException

      • getSkipRewriterIfRewritten

        public boolean getSkipRewriterIfRewritten()
        Get the flag which specifies whether this rewriter should be skipped if the query has been rewritten
        Specified by:
        getSkipRewriterIfRewritten in class QueryRewriteSearcher
        Returns:
        true if rewriter should be skipped, false otherwise

      • getRewriterName

        public java.lang.String getRewriterName()
        Get the name of the rewriter
        Specified by:
        getRewriterName in class QueryRewriteSearcher
        Returns:
        Name of the rewriter

      • getDefaultFSAs

        public java.util.HashMap<java.lang.String,​java.lang.String> getDefaultFSAs()
        Get default FSA dictionary names
        Specified by:
        getDefaultFSAs in class QueryRewriteSearcher
        Returns:
        Pair of FSA dictionary name and filename