rename _shard -> _index and also rename classes and variables

closes elastic#4584

docs/reference/modules/advanced-scripting.asciidoc

@@ -2,7 +2,7 @@
 == Text scoring in scripts
 
 
-Text features, such as term or document frequency for a specific term can be accessed in scripts (see <<modules-scripting, scripting documentation>> ) with the `_shard` variable. This can be useful if, for example, you want to implement your own scoring model using for example a script inside a <<query-dsl-function-score-query,function score query>>.
+Text features, such as term or document frequency for a specific term can be accessed in scripts (see <<modules-scripting, scripting documentation>> ) with the `_index` variable. This can be useful if, for example, you want to implement your own scoring model using for example a script inside a <<query-dsl-function-score-query,function score query>>.
 Statistics over the document collection are computed *per shard*, not per
 index.
 
@@ -35,15 +35,15 @@ depending on the shard the current document resides in.
 [float]
 === Shard statistics:
 
-`_shard.numDocs()`::
+`_index.numDocs()`::
 
     Number of documents in shard. 
 
-`_shard.maxDoc()`::
+`_index.maxDoc()`::
 
     Maximal document number in shard.
 
-`_shard.numDeletedDocs()`::
+`_index.numDeletedDocs()`::
 
     Number of deleted documents in shard.
 
@@ -52,49 +52,49 @@ depending on the shard the current document resides in.
 === Field statistics:
 
 Field statistics can be accessed with a subscript operator like this:
-`_shard['FIELD']`.
+`_index['FIELD']`.
 
 
-`_shard['FIELD'].docCount()`::
+`_index['FIELD'].docCount()`::
 
     Number of documents containing the field `FIELD`. Does not take deleted documents into account.
 
-`_shard['FIELD'].sumttf()`::
+`_index['FIELD'].sumttf()`::
 
     Sum of `ttf` over all terms that appear in field `FIELD` in all documents.
 
-`_shard['FIELD'].sumdf()`::
+`_index['FIELD'].sumdf()`::
 
     The sum of `df` s over all terms that appear in field `FIELD` in all
     documents.
 
 
 Field statistics are computed per shard and therfore these numbers can vary
 depending on the shard the current document resides in.
-The number of terms in a field cannot be accessed using the `_shard` variable. See <<mapping-core-types, word count mapping type>> on how to do that.
+The number of terms in a field cannot be accessed using the `_index` variable. See <<mapping-core-types, word count mapping type>> on how to do that.
 
 [float]
 === Term statistics:
 
 Term statistics for a field can be accessed with a subscript operator like
-this: `_shard['FIELD']['TERM']`. This will never return null, even if term or field does not exist. 
-If you do not need the term frequency, call `_shard['FIELD'].get('TERM', 0)`
+this: `_index['FIELD']['TERM']`. This will never return null, even if term or field does not exist. 
+If you do not need the term frequency, call `_index['FIELD'].get('TERM', 0)`
 to avoid uneccesary initialization of the frequencies. The flag will have only
 affect is your set the `index_options` to `docs` (see <<mapping-core-types, mapping documentation>>).
 
 
-`_shard['FIELD']['TERM'].df()`::
+`_index['FIELD']['TERM'].df()`::
 
     `df` of term `TERM` in field `FIELD`. Will be returned, even if the term
     is not present in the current document.
 
-`_shard['FIELD']['TERM'].ttf()`::
+`_index['FIELD']['TERM'].ttf()`::
 
     The sum of term frequencys of term `TERM` in field `FIELD` over all
     documents. Will be returned, even if the term is not present in the
     current document.
 
-`_shard['FIELD']['TERM'].tf()`::
+`_index['FIELD']['TERM'].tf()`::
 
     `tf` of term `TERM` in field `FIELD`. Will be 0 if the term is not present
     in the current document.
@@ -104,7 +104,7 @@ affect is your set the `index_options` to `docs` (see <<mapping-core-types, mapp
 === Term positions, offsets and payloads:
 
 If you need information on the positions of terms in a field, call
-`_shard['FIELD'].get('TERM', flag)` where flag can be
+`_index['FIELD'].get('TERM', flag)` where flag can be
 
 [horizontal]
 `_POSITIONS`::      if you need the positions of the term
@@ -119,7 +119,7 @@ example, the following will return an object holding the positions and payloads,
 as well as all statistics:
 
 
-    `_shard['FIELD'].get('TERM', _POSITIONS | _PAYLOADS)`
+    `_index['FIELD'].get('TERM', _POSITIONS | _PAYLOADS)`
 
 
 Positions can be accessed with an iterator that returns an object
@@ -164,7 +164,7 @@ Example: sums up all payloads for the term `foo`.
 
 [source,mvel]
 ---------------------------------------------------------
-termInfo = _shard['my_field'].get('foo',_PAYLOADS);
+termInfo = _index['my_field'].get('foo',_PAYLOADS);
 score = 0;
 for (pos : termInfo) {
     score = score + pos.payloadAsInt(0);
@@ -176,8 +176,8 @@ return score;
 [float]
 === Term vectors:
 
-The `_shard` variable can only be used to gather statistics for single terms. If you want to use information on all terms in a field, you must store the term vectors (set `term_vector` in the mapping as described in the <<mapping-core-types,mapping documentation>>). To access them, call
-`_shard.getTermVectors()` to get a
+The `_index` variable can only be used to gather statistics for single terms. If you want to use information on all terms in a field, you must store the term vectors (set `term_vector` in the mapping as described in the <<mapping-core-types,mapping documentation>>). To access them, call
+`_index.getTermVectors()` to get a
 https://lucene.apache.org/core/4_0_0/core/org/apache/lucene/index/Fields.html[Fields]
 instance. This object can then be used as described in https://lucene.apache.org/core/4_0_0/core/org/apache/lucene/index/Fields.html[lucene doc] to iterate over fields and then for each field iterate over each term in the field.
 The method will return null if the term vectors were not stored.

src/main/java/org/elasticsearch/script/AbstractSearchScript.java

@@ -19,7 +19,7 @@
 
 package org.elasticsearch.script;
 
-import org.elasticsearch.search.lookup.ShardTermsLookup;
+import org.elasticsearch.search.lookup.IndexLookup;
 
 import org.apache.lucene.index.AtomicReaderContext;
 import org.apache.lucene.search.Scorer;
@@ -93,8 +93,8 @@ protected final SourceLookup source() {
     /**
      * Allows to access statistics on terms and fields.
      */
-    protected final ShardTermsLookup shardTerms() {
-        return lookup.shardTerms();
+    protected final IndexLookup indexLookup() {
+        return lookup.indexLookup();
     }
 
     /**

src/main/java/org/elasticsearch/search/lookup/CachedPositionIterator.java

@@ -30,8 +30,8 @@
  * */
 public class CachedPositionIterator extends PositionIterator {
 
-    public CachedPositionIterator(ScriptTerm termInfo) {
-        super(termInfo);
+    public CachedPositionIterator(IndexFieldTerm indexFieldTerm) {
+        super(indexFieldTerm);
     }
 
     // all payloads of the term in the current document in one bytes array.

src/main/java/org/elasticsearch/search/lookup/ScriptTerms.java → src/main/java/org/elasticsearch/search/lookup/IndexField.java

@@ -30,14 +30,14 @@
 /**
  * Script interface to all information regarding a field.
  * */
-public class ScriptTerms extends MinimalMap<String, ScriptTerm> {
+public class IndexField extends MinimalMap<String, IndexFieldTerm> {
 
     /*
      * TermsInfo Objects that represent the Terms are stored in this map when
      * requested. Information such as frequency, doc frequency and positions
      * information can be retrieved from the TermInfo objects in this map.
      */
-    private final Map<String, ScriptTerm> terms = new HashMap<String, ScriptTerm>();
+    private final Map<String, IndexFieldTerm> terms = new HashMap<String, IndexFieldTerm>();
 
     // the name of this field
     private final String fieldName;
@@ -46,7 +46,7 @@ public class ScriptTerms extends MinimalMap<String, ScriptTerm> {
      * The holds the current reader. We need it to populate the field
      * statistics. We just delegate all requests there
      */
-    private ShardTermsLookup shardTermsLookup;
+    private IndexLookup indexLookup;
 
     /*
      * General field statistics such as number of documents containing the
@@ -58,7 +58,7 @@ public class ScriptTerms extends MinimalMap<String, ScriptTerm> {
      * Uodate posting lists in all TermInfo objects
      */
     void setReader(AtomicReader reader) {
-        for (ScriptTerm ti : terms.values()) {
+        for (IndexFieldTerm ti : terms.values()) {
             ti.setNextReader(reader);
         }
     }
@@ -68,15 +68,15 @@ void setReader(AtomicReader reader) {
      * statistics of this field. Information on specific terms in this field can
      * be accessed by calling get(String term).
      */
-    public ScriptTerms(String fieldName, ShardTermsLookup shardTermsLookup) throws IOException {
+    public IndexField(String fieldName, IndexLookup indexLookup) throws IOException {
 
         assert fieldName != null;
         this.fieldName = fieldName;
 
-        assert shardTermsLookup != null;
-        this.shardTermsLookup = shardTermsLookup;
+        assert indexLookup != null;
+        this.indexLookup = indexLookup;
 
-        fieldStats = shardTermsLookup.getIndexSearcher().collectionStatistics(fieldName);
+        fieldStats = this.indexLookup.getIndexSearcher().collectionStatistics(fieldName);
     }
 
     /* get number of documents containing the field */
@@ -107,29 +107,29 @@ public long sumdf() throws IOException {
      * advance which terms are requested, we could provide an array which the
      * user could then iterate over.
      */
-    public ScriptTerm get(Object key, int flags) {
+    public IndexFieldTerm get(Object key, int flags) {
         String termString = (String) key;
-        ScriptTerm termInfo = terms.get(termString);
+        IndexFieldTerm indexFieldTerm = terms.get(termString);
         // see if we initialized already...
-        if (termInfo == null) {
-            termInfo = new ScriptTerm(termString, fieldName, shardTermsLookup, flags);
-            terms.put(termString, termInfo);
+        if (indexFieldTerm == null) {
+            indexFieldTerm = new IndexFieldTerm(termString, fieldName, indexLookup, flags);
+            terms.put(termString, indexFieldTerm);
         }
-        termInfo.validateFlags(flags);
-        return termInfo;
+        indexFieldTerm.validateFlags(flags);
+        return indexFieldTerm;
     }
 
     /*
      * Returns a TermInfo object that can be used to access information on
      * specific terms. flags can be set as described in TermInfo.
      */
-    public ScriptTerm get(Object key) {
+    public IndexFieldTerm get(Object key) {
         // per default, do not initialize any positions info
-        return get(key, ShardTermsLookup.FLAG_FREQUENCIES);
+        return get(key, IndexLookup.FLAG_FREQUENCIES);
     }
 
     public void setDocIdInTerms(int docId) {
-        for (ScriptTerm ti : terms.values()) {
+        for (IndexFieldTerm ti : terms.values()) {
             ti.setNextDoc(docId);
         }
     }

src/main/java/org/elasticsearch/search/lookup/ScriptTerm.java → src/main/java/org/elasticsearch/search/lookup/IndexFieldTerm.java

@@ -30,7 +30,7 @@
 /**
  * Holds all information on a particular term in a field.
  * */
-public class ScriptTerm implements Iterable<TermPosition> {
+public class IndexFieldTerm implements Iterable<TermPosition> {
 
     // The posting list for this term. Is null if the term or field does not
     // exist. Can be DocsEnum or DocsAndPositionsEnum.
@@ -90,16 +90,16 @@ void setNextReader(AtomicReader reader) {
     }
 
     private boolean shouldRetrieveFrequenciesOnly() {
-        return (flags & ~ShardTermsLookup.FLAG_FREQUENCIES) == 0;
+        return (flags & ~IndexLookup.FLAG_FREQUENCIES) == 0;
     }
 
     private int getLuceneFrequencyFlag(int flags) {
-        return (flags & ShardTermsLookup.FLAG_FREQUENCIES) > 0 ? DocsEnum.FLAG_FREQS : DocsEnum.FLAG_NONE;
+        return (flags & IndexLookup.FLAG_FREQUENCIES) > 0 ? DocsEnum.FLAG_FREQS : DocsEnum.FLAG_NONE;
     }
 
     private int getLucenePositionsFlags(int flags) {
-        int lucenePositionsFlags = (flags & ShardTermsLookup.FLAG_PAYLOADS) > 0 ? DocsAndPositionsEnum.FLAG_PAYLOADS : 0x0;
-        lucenePositionsFlags |= (flags & ShardTermsLookup.FLAG_OFFSETS) > 0 ? DocsAndPositionsEnum.FLAG_OFFSETS : 0x0;
+        int lucenePositionsFlags = (flags & IndexLookup.FLAG_PAYLOADS) > 0 ? DocsAndPositionsEnum.FLAG_PAYLOADS : 0x0;
+        lucenePositionsFlags |= (flags & IndexLookup.FLAG_OFFSETS) > 0 ? DocsAndPositionsEnum.FLAG_OFFSETS : 0x0;
         return lucenePositionsFlags;
     }
 
@@ -162,19 +162,19 @@ public void setNextDoc(int docId) {
             }
             iterator.nextDoc();
         } catch (IOException e) {
-            throw new ElasticSearchException("While trying to initialize term positions in ScriptTerm.setNextDoc() ", e);
+            throw new ElasticSearchException("While trying to initialize term positions in IndexFieldTerm.setNextDoc() ", e);
         }
     }
 
-    public ScriptTerm(String term, String fieldName, ShardTermsLookup shardTermsLookup, int flags) {
+    public IndexFieldTerm(String term, String fieldName, IndexLookup indexLookup, int flags) {
         assert fieldName != null;
         this.fieldName = fieldName;
         assert term != null;
         this.term = term;
-        assert shardTermsLookup != null;
+        assert indexLookup != null;
         identifier = new Term(fieldName, (String) term);
         this.flags = flags;
-        boolean doRecord = ((flags & ShardTermsLookup.FLAG_CACHE) > 0);
+        boolean doRecord = ((flags & IndexLookup.FLAG_CACHE) > 0);
         if (withPositions()) {
             if (!doRecord) {
                 iterator = new PositionIterator(this);
@@ -184,11 +184,11 @@ public ScriptTerm(String term, String fieldName, ShardTermsLookup shardTermsLook
         } else {
             iterator = new PositionIterator(this);
         }
-        setNextReader(shardTermsLookup.getReader());
-        setNextDoc(shardTermsLookup.getDocId());
+        setNextReader(indexLookup.getReader());
+        setNextDoc(indexLookup.getDocId());
         try {
-            termStats = shardTermsLookup.getIndexSearcher().termStatistics(identifier,
-                    TermContext.build(shardTermsLookup.getReaderContext(), identifier));
+            termStats = indexLookup.getIndexSearcher().termStatistics(identifier,
+                    TermContext.build(indexLookup.getReaderContext(), identifier));
         } catch (IOException e) {
             throw new ElasticSearchException("Cannot get term statistics: ", e);
         }
@@ -199,15 +199,15 @@ private boolean withPositions() {
     }
 
     protected boolean shouldRetrievePositions() {
-        return (flags & ShardTermsLookup.FLAG_POSITIONS) > 0;
+        return (flags & IndexLookup.FLAG_POSITIONS) > 0;
     }
 
     protected boolean shouldRetrieveOffsets() {
-        return (flags & ShardTermsLookup.FLAG_OFFSETS) > 0;
+        return (flags & IndexLookup.FLAG_OFFSETS) > 0;
     }
 
     protected boolean shouldRetrievePayloads() {
-        return (flags & ShardTermsLookup.FLAG_PAYLOADS) > 0;
+        return (flags & IndexLookup.FLAG_PAYLOADS) > 0;
     }
 
     public int tf() throws IOException {
@@ -241,24 +241,24 @@ private String getCalledStatement(int flags2) {
     }
 
     private String getCallStatement(String calledFlags) {
-        return "_shard['" + this.fieldName + "'].get('" + this.term + "', " + calledFlags + ")";
+        return "_index['" + this.fieldName + "'].get('" + this.term + "', " + calledFlags + ")";
     }
 
     private String getFlagsString(int flags2) {
         String flagsString = null;
-        if ((flags2 & ShardTermsLookup.FLAG_FREQUENCIES) != 0) {
+        if ((flags2 & IndexLookup.FLAG_FREQUENCIES) != 0) {
             flagsString = anddToFlagsString(flagsString, "_FREQUENCIES");
         }
-        if ((flags2 & ShardTermsLookup.FLAG_POSITIONS) != 0) {
+        if ((flags2 & IndexLookup.FLAG_POSITIONS) != 0) {
             flagsString = anddToFlagsString(flagsString, "_POSITIONS");
         }
-        if ((flags2 & ShardTermsLookup.FLAG_OFFSETS) != 0) {
+        if ((flags2 & IndexLookup.FLAG_OFFSETS) != 0) {
             flagsString = anddToFlagsString(flagsString, "_OFFSETS");
         }
-        if ((flags2 & ShardTermsLookup.FLAG_PAYLOADS) != 0) {
+        if ((flags2 & IndexLookup.FLAG_PAYLOADS) != 0) {
             flagsString = anddToFlagsString(flagsString, "_PAYLOADS");
         }
-        if ((flags2 & ShardTermsLookup.FLAG_CACHE) != 0) {
+        if ((flags2 & IndexLookup.FLAG_CACHE) != 0) {
             flagsString = anddToFlagsString(flagsString, "_CACHE");
         }
         return flagsString;