Do not create all the results at once. Be a bit lazy.

We don't need to generate a vector of result when we do a search.
We better to just keep the handle to the current MSetIterator and
generate the wanted values when needed.

include/searcher.h

@@ -35,14 +35,16 @@
 
 using namespace std;
 
-struct Result
+class Result
 {
-  string url;
-  string title;
-  int score;
-  string snippet;
-  int wordCount;
-  int size;
+  public:
+    virtual ~Result() {};
+    virtual std::string get_url() = 0;
+    virtual std::string get_title() = 0;
+    virtual int get_score() = 0;
+    virtual std::string get_snippet() = 0;
+    virtual int get_wordCount() = 0;
+    virtual int get_size() = 0;
 };
 
 namespace kiwix {
@@ -55,7 +57,8 @@ namespace kiwix {
 
     void search(std::string &search, unsigned int resultStart,
 		unsigned int resultEnd, const bool verbose=false);
-    bool getNextResult(string &url, string &title, unsigned int &score);
+    virtual Result* getNextResult() = 0;
+    virtual void restart_search() = 0;
     unsigned int getEstimatedResultCount();
     bool setProtocolPrefix(const std::string prefix);
     bool setSearchProtocolPrefix(const std::string prefix);
@@ -72,8 +75,6 @@ namespace kiwix {
     virtual void searchInIndex(string &search, const unsigned int resultStart,
 			       const unsigned int resultEnd, const bool verbose=false) = 0;
 
-    std::vector<Result> results;
-    std::vector<Result>::iterator resultOffset;
     std::string searchPattern;
     std::string protocolPrefix;
     std::string searchProtocolPrefix;

include/xapianSearcher.h

@@ -27,6 +27,23 @@ using namespace std;
 
 namespace kiwix {
 
+  class XapianResult : public Result {
+    public:
+      XapianResult(Xapian::MSetIterator& iterator);
+      virtual ~XapianResult() {};
+
+      virtual std::string get_url();
+      virtual std::string get_title();
+      virtual int get_score();
+      virtual std::string get_snippet();
+      virtual int get_wordCount();
+      virtual int get_size();
+
+    private:
+      Xapian::MSetIterator iterator;
+      Xapian::Document document;
+  };
+
   class NoXapianIndexInZim: public exception {
     virtual const char* what() const throw() {
       return "There is no fulltext index in the zim file";
@@ -40,6 +57,8 @@ namespace kiwix {
     virtual ~XapianSearcher() {};
     void searchInIndex(string &search, const unsigned int resultStart, const unsigned int resultEnd, 
 		       const bool verbose=false);
+    virtual Result* getNextResult();
+    void restart_search();
 
   protected:
     void closeIndex();
@@ -47,6 +66,8 @@ namespace kiwix {
 
     Xapian::Database readableDatabase;
     Xapian::Stem stemmer;
+    Xapian::MSet results;
+    Xapian::MSetIterator current_result;
   };
 
 }

src/android/kiwix.cpp

@@ -460,19 +460,18 @@ JNIEXPORT jstring JNICALL Java_org_kiwix_kiwixlib_JNIKiwix_indexedQuery
   (JNIEnv *env, jclass obj, jstring query, jint count) {
   std::string cQuery = jni2c(query, env);
   unsigned int cCount = jni2c(count);
-  std::string url;
-  std::string title;
+  kiwix::Result *p_result;
   std::string result;
-  unsigned int score;
       
   pthread_mutex_lock(&searcherLock);
   try {
     if (searcher != NULL) {
       searcher->search(cQuery, 0, count);
-      while (searcher->getNextResult(url, title, score) &&
-	     !title.empty() &&
-	     !url.empty()) {
-	result += title + "\n";
+      while ( (p_result = searcher->getNextResult()) &&
+	     !(p_result->get_title().empty()) &&
+	     !(p_result->get_url().empty())) {
+	result += p_result->get_title() + "\n";
+	delete p_result;
       }
     }
   } catch (...) {

src/searcher.cpp

@@ -81,7 +81,6 @@ namespace kiwix {
       this->resultEnd = resultEnd;
       string unaccentedSearch = removeAccents(search);
       searchInIndex(unaccentedSearch, resultStart, resultEnd, verbose);
-      this->resultOffset = this->results.begin();
     }
 
     return;
@@ -89,8 +88,6 @@ namespace kiwix {
 
   /* Reset the results */
   void Searcher::reset() {
-    this->results.clear();
-    this->resultOffset = this->results.begin();
     this->estimatedResultCount = 0;
     this->searchPattern = "";
     return;
@@ -101,30 +98,6 @@ namespace kiwix {
     return this->estimatedResultCount;
   }
 
-  /* Get next result */
-  bool Searcher::getNextResult(string &url, string &title, unsigned int &score) {
-    bool retVal = false;
-
-    if (this->resultOffset != this->results.end()) {
-
-      /* url */
-      url = this->resultOffset->url;
-
-      /* title */
-      title = this->resultOffset->title;
-
-      /* score */
-      score =  this->resultOffset->score;
-
-      /* increment the cursor for the next call */
-      this->resultOffset++;
-
-      retVal = true;
-    }
-
-    return retVal;
-  }
-
   bool Searcher::setProtocolPrefix(const std::string prefix) {
     this->protocolPrefix = prefix;
     return true;
@@ -149,23 +122,24 @@ namespace kiwix {
     CDT oData;
     CDT resultsCDT(CDT::ARRAY_VAL);
 
-    this->resultOffset = this->results.begin();
-    while (this->resultOffset != this->results.end()) {
+    this->restart_search();
+    Result * p_result = NULL;
+    while ( (p_result = this->getNextResult()) ) {
       CDT result;
-      result["title"] = this->resultOffset->title;
-      result["url"] = this->resultOffset->url;
-      result["snippet"] = this->resultOffset->snippet;
+      result["title"] = p_result->get_title();
+      result["url"] = p_result->get_url();
+      result["snippet"] = p_result->get_snippet();
 
-      if (this->resultOffset->size >= 0)
-    result["size"] = kiwix::beautifyInteger(this->resultOffset->size);
+      if (p_result->get_size() >= 0)
+        result["size"] = kiwix::beautifyInteger(p_result->get_size());
 
-      if (this->resultOffset->wordCount >= 0)
-    result["wordCount"] = kiwix::beautifyInteger(this->resultOffset->wordCount);
+      if (p_result->get_wordCount() >= 0)
+        result["wordCount"] = kiwix::beautifyInteger(p_result->get_wordCount());
 
       resultsCDT.PushBack(result);
-      this->resultOffset++;
+      delete p_result;
     }
-    this->resultOffset = this->results.begin();
+    this->restart_search();
     oData["results"] = resultsCDT;
 
     // pages

src/xapianSearcher.cpp

@@ -68,32 +68,55 @@ namespace kiwix {
     enquire.set_query(query);
 
     /* Get the results */
-    Xapian::MSet matches = enquire.get_mset(resultStart, resultEnd - resultStart);
-    
-    Xapian::MSetIterator i;
-    for (i = matches.begin(); i != matches.end(); ++i) {
-      Xapian::Document doc = i.get_document();
-      
-      Result result;
-      result.url = doc.get_data();
-      result.title = doc.get_value(0);
-      result.snippet = doc.get_value(1);
-      result.size = (doc.get_value(2).empty() == true ? -1 : atoi(doc.get_value(2).c_str()));
-      result.wordCount = (doc.get_value(3).empty() == true ? -1 : atoi(doc.get_value(3).c_str()));
-      result.score = i.get_percent();
-      
-      this->results.push_back(result);
-
-      if (verbose) {
-	std::cout << "Document ID " << *i << "   \t";
-	std::cout << i.get_percent() << "% ";
-	std::cout << "\t[" << doc.get_data() << "] - " << doc.get_value(0) << std::endl;
-      }
-    }
+    this->results = enquire.get_mset(resultStart, resultEnd - resultStart);
+    this->current_result = this->results.begin();
 
     /* Update the global resultCount value*/
-    this->estimatedResultCount = matches.get_matches_estimated();
-
-    return;
+    this->estimatedResultCount = this->results.get_matches_estimated();
   }
-}
+
+  /* Get next result */
+  Result* XapianSearcher::getNextResult() {
+    if (this->current_result != this->results.end()) {
+      XapianResult* result = new XapianResult(this->current_result);
+      this->current_result++;
+      return result;
+    }
+    return NULL;
+  }
+
+  void XapianSearcher::restart_search() {
+    this->current_result = this->results.begin();
+  }
+
+  XapianResult::XapianResult(Xapian::MSetIterator& iterator):
+    iterator(iterator),
+    document(iterator.get_document())
+  {
+  }
+
+  std::string XapianResult::get_url() {
+    return document.get_data();
+  }
+
+  std::string XapianResult::get_title() {
+      return document.get_value(0);
+  }
+
+  int XapianResult::get_score() {
+    return iterator.get_percent();
+  }
+
+  std::string XapianResult::get_snippet() {
+      return document.get_value(1);
+  }
+
+  int XapianResult::get_size() {
+      return document.get_value(2).empty() == true ? -1 : atoi(document.get_value(2).c_str());
+  }
+
+  int XapianResult::get_wordCount() {
+        return document.get_value(3).empty() == true ? -1 : atoi(document.get_value(3).c_str());
+  }
+
+} // Kiwix namespace