svn commit: r1352039 - in /lucene/dev/branches/branch_4x: ./ lucene/ lucene/CHANGES.txt lucene/facet/ lucene/facet/src/java/org/apache/lucene/facet/taxonomy/directory/DirectoryTaxonomyWriter.java

[sh...@apache.org]

Author: shaie
Date: Wed Jun 20 10:45:00 2012
New Revision: 1352039

URL: http://svn.apache.org/viewvc?rev=1352039&view=rev
Log:
LUCENE-4156: remove synchronization from DirectoryTaxonomyWriter.getSize()

Modified:
    lucene/dev/branches/branch_4x/   (props changed)
    lucene/dev/branches/branch_4x/lucene/   (props changed)
    lucene/dev/branches/branch_4x/lucene/CHANGES.txt   (contents, props changed)
    lucene/dev/branches/branch_4x/lucene/facet/   (props changed)
    lucene/dev/branches/branch_4x/lucene/facet/src/java/org/apache/lucene/facet/taxonomy/directory/DirectoryTaxonomyWriter.java

Modified: lucene/dev/branches/branch_4x/lucene/CHANGES.txt
URL: http://svn.apache.org/viewvc/lucene/dev/branches/branch_4x/lucene/CHANGES.txt?rev=1352039&r1=1352038&r2=1352039&view=diff
==============================================================================
--- lucene/dev/branches/branch_4x/lucene/CHANGES.txt (original)
+++ lucene/dev/branches/branch_4x/lucene/CHANGES.txt Wed Jun 20 10:45:00 2012
@@ -980,6 +980,9 @@ Optimizations
 
 * LUCENE-4098: Add bulk get/set methods to PackedInts (Adrien Grand
   via Mike McCandless)
+  
+* LUCENE-4156: DirectoryTaxonomyWriter.getSize is no longer synchronized.
+  (Shai Erera, Sivan Yogev)
 
 Bug fixes
 

Modified: lucene/dev/branches/branch_4x/lucene/facet/src/java/org/apache/lucene/facet/taxonomy/directory/DirectoryTaxonomyWriter.java
URL: http://svn.apache.org/viewvc/lucene/dev/branches/branch_4x/lucene/facet/src/java/org/apache/lucene/facet/taxonomy/directory/DirectoryTaxonomyWriter.java?rev=1352039&r1=1352038&r2=1352039&view=diff
==============================================================================
--- lucene/dev/branches/branch_4x/lucene/facet/src/java/org/apache/lucene/facet/taxonomy/directory/DirectoryTaxonomyWriter.java (original)
+++ lucene/dev/branches/branch_4x/lucene/facet/src/java/org/apache/lucene/facet/taxonomy/directory/DirectoryTaxonomyWriter.java Wed Jun 20 10:45:00 2012
@@ -103,7 +103,6 @@ public class DirectoryTaxonomyWriter imp
   /** Records the taxonomy index creation time, updated on replaceTaxonomy as well. */
   private String createTime;
   
-  private int nextID;
   private char delimiter = Consts.DEFAULT_DELIMITER;
   private SinglePositionTokenStream parentStream = new SinglePositionTokenStream(Consts.PAYLOAD_PARENT);
   private Field parentStreamField;
@@ -126,6 +125,7 @@ public class DirectoryTaxonomyWriter imp
   private volatile boolean shouldRefreshReaderManager;
   private volatile boolean isClosed = false;
   private volatile ParentArray parentArray;
+  private volatile int nextID;
 
   /** Reads the commit data from a Directory. */
   private static Map<String, String> readCommitData(Directory dir) throws IOException {
@@ -135,16 +135,16 @@ public class DirectoryTaxonomyWriter imp
   }
   
   /**
-   * setDelimiter changes the character that the taxonomy uses in its internal
-   * storage as a delimiter between category components. Do not use this
-   * method unless you really know what you are doing. It has nothing to do
-   * with whatever character the application may be using to represent
-   * categories for its own use.
-   * <P>
+   * Changes the character that the taxonomy uses in its internal storage as a
+   * delimiter between category components. Do not use this method unless you
+   * really know what you are doing. It has nothing to do with whatever
+   * character the application may be using to represent categories for its own
+   * use.
+   * <p>
    * If you do use this method, make sure you call it before any other methods
-   * that actually queries the taxonomy. Moreover, make sure you always pass
-   * the same delimiter for all LuceneTaxonomyWriter and LuceneTaxonomyReader
-   * objects you create for the same directory.
+   * that actually queries the taxonomy. Moreover, make sure you always pass the
+   * same delimiter for all taxonomy writer and reader instances you create for
+   * the same directory.
    */
   public void setDelimiter(char delimiter) {
     ensureOpen();
@@ -226,7 +226,7 @@ public class DirectoryTaxonomyWriter imp
     parentStreamField = new Field(Consts.FIELD_PAYLOADS, parentStream, ft);
     fullPathField = new StringField(Consts.FULL, "", Field.Store.YES);
 
-    this.nextID = indexWriter.maxDoc();
+    nextID = indexWriter.maxDoc();
 
     if (cache == null) {
       cache = defaultTaxonomyWriterCache();
@@ -706,43 +706,28 @@ public class DirectoryTaxonomyWriter imp
     indexWriter.prepareCommit(combinedCommitData(commitUserData));
   }
   
-  /**
-   * getSize() returns the number of categories in the taxonomy.
-   * <P>
-   * Because categories are numbered consecutively starting with 0, it means
-   * the taxonomy contains ordinals 0 through getSize()-1.
-   * <P>
-   * Note that the number returned by getSize() is often slightly higher than
-   * the number of categories inserted into the taxonomy; This is because when
-   * a category is added to the taxonomy, its ancestors are also added
-   * automatically (including the root, which always get ordinal 0).
-   */
   @Override
-  synchronized public int getSize() {
+  public int getSize() {
     ensureOpen();
-    return indexWriter.maxDoc();
+    return nextID;
   }
-
+  
   /**
-   * Set the number of cache misses before an attempt is made to read the
-   * entire taxonomy into the in-memory cache.
-   * <P> 
-   * LuceneTaxonomyWriter holds an in-memory cache of recently seen
-   * categories to speed up operation. On each cache-miss, the on-disk index
-   * needs to be consulted. When an existing taxonomy is opened, a lot of
-   * slow disk reads like that are needed until the cache is filled, so it
-   * is more efficient to read the entire taxonomy into memory at once.
-   * We do this complete read after a certain number (defined by this method)
-   * of cache misses.
-   * <P>
-   * If the number is set to <CODE>0</CODE>, the entire taxonomy is read
-   * into the cache on first use, without fetching individual categories
-   * first.
-   * <P>
-   * Note that if the memory cache of choice is limited in size, and cannot
-   * hold the entire content of the on-disk taxonomy, then it is never
-   * read in its entirety into the cache, regardless of the setting of this
-   * method. 
+   * Set the number of cache misses before an attempt is made to read the entire
+   * taxonomy into the in-memory cache.
+   * <p>
+   * This taxonomy writer holds an in-memory cache of recently seen categories
+   * to speed up operation. On each cache-miss, the on-disk index needs to be
+   * consulted. When an existing taxonomy is opened, a lot of slow disk reads
+   * like that are needed until the cache is filled, so it is more efficient to
+   * read the entire taxonomy into memory at once. We do this complete read
+   * after a certain number (defined by this method) of cache misses.
+   * <p>
+   * If the number is set to {@code 0}, the entire taxonomy is read into the
+   * cache on first use, without fetching individual categories first.
+   * <p>
+   * NOTE: it is assumed that this method is called immediately after the
+   * taxonomy writer has been created.
    */
   public void setCacheMissesUntilFill(int i) {
     ensureOpen();
@@ -841,8 +826,8 @@ public class DirectoryTaxonomyWriter imp
     // Note: the following if() just enforces that a user can never ask
     // for the parent of a nonexistant category - even if the parent array
     // was allocated bigger than it really needs to be.
-    if (ordinal >= getSize()) {
-      throw new ArrayIndexOutOfBoundsException();
+    if (ordinal >= nextID) {
+      throw new ArrayIndexOutOfBoundsException("requested ordinal is bigger than the largest ordinal in the taxonomy");
     }
     return getParentArray().getArray()[ordinal];
   }