svn commit: r701156 - in /db/derby/code/trunk/java/client/org/apache/derby/client/am: LOBStateTracker.java ResultSet.java

[kr...@apache.org]

Author: kristwaa
Date: Thu Oct  2 08:29:43 2008
New Revision: 701156

URL: http://svn.apache.org/viewvc?rev=701156&view=rev
Log:
DERBY-3601: Optimize LOBStateTracker for non-locator servers.
>From the Jira comment (improvements implemented);
  - LOBStateTracker.checkCurrentRow(): couldn't Arrays.fill() be moved inside the if block?
  - should discardState() and markAccessed() check the release flag?
  - should ResultSet.createLOBColumnTracker() use LOBStateTracker.NO_OP_TRACKER instead of allocating a new when serverSupportsLocators() returns false? 
Patch file: derby-3601-2a-non_locator_optimization.diff

Modified:
    db/derby/code/trunk/java/client/org/apache/derby/client/am/LOBStateTracker.java
    db/derby/code/trunk/java/client/org/apache/derby/client/am/ResultSet.java

Modified: db/derby/code/trunk/java/client/org/apache/derby/client/am/LOBStateTracker.java
URL: http://svn.apache.org/viewvc/db/derby/code/trunk/java/client/org/apache/derby/client/am/LOBStateTracker.java?rev=701156&r1=701155&r2=701156&view=diff
==============================================================================
--- db/derby/code/trunk/java/client/org/apache/derby/client/am/LOBStateTracker.java (original)
+++ db/derby/code/trunk/java/client/org/apache/derby/client/am/LOBStateTracker.java Thu Oct  2 08:29:43 2008
@@ -130,9 +130,9 @@
                     }
                 }
             }
+            // Reset state for the next row.
+            Arrays.fill(this.published, false);
         }
-        // Reset state for the next row.
-        Arrays.fill(this.published, false);
     }
 
     /**
@@ -143,11 +143,13 @@
      * to release them from the client side in this case.
      */
     void discardState() {
-        // Force the state to published for all LOB columns.
-        // This will cause checkCurrentRow to ignore all LOBs on the next
-        // invocation. The method markAsPublished cannot be called before after
-        // checkCurrentRow has been called again.
-        Arrays.fill(this.published, true);
+        if (this.doRelease) {
+            // Force the state to published for all LOB columns.
+            // This will cause checkCurrentRow to ignore all LOBs on the next
+            // invocation. The method markAsPublished cannot be called before
+            // after checkCurrentRow has been called again.
+            Arrays.fill(this.published, true);
+        }
     }
 
     /**
@@ -160,7 +162,9 @@
      * @param index 1-based column index
      */
     void markAsPublished(int index) {
-        int internalIndex = Arrays.binarySearch(this.columns, index);
-        this.published[internalIndex] = true;
+        if (this.doRelease) {
+            int internalIndex = Arrays.binarySearch(this.columns, index);
+            this.published[internalIndex] = true;
+        }
     }
 }

Modified: db/derby/code/trunk/java/client/org/apache/derby/client/am/ResultSet.java
URL: http://svn.apache.org/viewvc/db/derby/code/trunk/java/client/org/apache/derby/client/am/ResultSet.java?rev=701156&r1=701155&r2=701156&view=diff
==============================================================================
--- db/derby/code/trunk/java/client/org/apache/derby/client/am/ResultSet.java (original)
+++ db/derby/code/trunk/java/client/org/apache/derby/client/am/ResultSet.java Thu Oct  2 08:29:43 2008
@@ -6217,14 +6217,17 @@
     /**
      * Initializes the LOB state tracker.
      * <p>
-     * The state tracker is used to free LOB locators on the server.
+     * The state tracker is used to free LOB locators on the server. If the
+     * server doesn't support locators, or there are no LOBs in the result set,
+     * a no-op tracker will be used.
      */
     final void createLOBColumnTracker() {
         if (SanityManager.DEBUG) {
             SanityManager.ASSERT(this.lobState == null,
                     "LOB state tracker already initialized.");
         }
-        if (this.resultSetMetaData_.hasLobColumns()) {
+        if (this.connection_.supportsSessionDataCaching() &&
+                this.resultSetMetaData_.hasLobColumns()) {
             final int columnCount = this.resultSetMetaData_.columns_;
             int lobCount = 0;
             int[] tmpIndexes = new int[columnCount];
@@ -6241,8 +6244,7 @@
             boolean[] isBlob = new boolean[lobCount];
             System.arraycopy(tmpIndexes, 0, lobIndexes, 0, lobCount);
             System.arraycopy(tmpIsBlob, 0, isBlob, 0, lobCount);
-            this.lobState = new LOBStateTracker(lobIndexes, isBlob,
-                    this.connection_.serverSupportsLocators());
+            this.lobState = new LOBStateTracker(lobIndexes, isBlob, true);
         } else {
             // Use a no-op state tracker to simplify code expecting a tracker.
             this.lobState = LOBStateTracker.NO_OP_TRACKER;