From 020d33c8aaceba8f4c890b6f377f478e966b8f98 Mon Sep 17 00:00:00 2001
From: Ray Greenwell <ray@threerings.net>
Date: Mon, 20 Sep 2010 23:21:06 +0000
Subject: [PATCH] Was looking at how some things work and made a few drive-by
 optimizations to FindAllQuery. - We don't need to destructively modify the
 Set of keys to fetch if we hold   on to one iterator. - We can create an
 ArrayList that won't need to grow if our keys Iterable   happens to be a
 Collection. - And, just generally prefer Lists factories to specific
 constructors.

---
 .../com/samskivert/depot/impl/FindAllKeysQuery.java |  5 +++--
 .../com/samskivert/depot/impl/FindAllQuery.java     | 13 +++++++------
 2 files changed, 10 insertions(+), 8 deletions(-)

diff --git a/src/main/java/com/samskivert/depot/impl/FindAllKeysQuery.java b/src/main/java/com/samskivert/depot/impl/FindAllKeysQuery.java
index ae34965..ce2da88 100644
--- a/src/main/java/com/samskivert/depot/impl/FindAllKeysQuery.java
+++ b/src/main/java/com/samskivert/depot/impl/FindAllKeysQuery.java
@@ -20,7 +20,6 @@
 
 package com.samskivert.depot.impl;
 
-import java.util.ArrayList;
 import java.util.List;
 
 import java.sql.Connection;
@@ -28,6 +27,8 @@ import java.sql.PreparedStatement;
 import java.sql.ResultSet;
 import java.sql.SQLException;
 
+import com.google.common.collect.Lists;
+
 import com.samskivert.jdbc.DatabaseLiaison;
 import com.samskivert.depot.DatabaseException;
 import com.samskivert.depot.Key;
@@ -71,7 +72,7 @@ public class FindAllKeysQuery<T extends PersistentRecord> extends Query<List<Key
     public List<Key<T>> invoke (PersistenceContext ctx, Connection conn, DatabaseLiaison liaison)
         throws SQLException
     {
-        List<Key<T>> keys = new ArrayList<Key<T>>();
+        List<Key<T>> keys = Lists.newArrayList();
         PreparedStatement stmt = _builder.prepare(conn);
         ResultSet rs = stmt.executeQuery();
         while (rs.next()) {
diff --git a/src/main/java/com/samskivert/depot/impl/FindAllQuery.java b/src/main/java/com/samskivert/depot/impl/FindAllQuery.java
index 4900253..60f1b95 100644
--- a/src/main/java/com/samskivert/depot/impl/FindAllQuery.java
+++ b/src/main/java/com/samskivert/depot/impl/FindAllQuery.java
@@ -25,7 +25,7 @@ import java.sql.PreparedStatement;
 import java.sql.ResultSet;
 import java.sql.SQLException;
 
-import java.util.ArrayList;
+import java.util.Collection;
 import java.util.Iterator;
 import java.util.List;
 import java.util.Map;
@@ -228,7 +228,7 @@ public abstract class FindAllQuery<T extends PersistentRecord> extends Query<Lis
         public List<T> invoke (PersistenceContext ctx, Connection conn, DatabaseLiaison liaison)
             throws SQLException
         {
-            List<T> result = new ArrayList<T>();
+            List<T> result = Lists.newArrayList();
             SQLBuilder builder = ctx.getSQLBuilder(DepotTypes.getDepotTypes(ctx, _select));
             builder.newQuery(_select);
             ResultSet rs = builder.prepare(conn).executeQuery();
@@ -288,7 +288,9 @@ public abstract class FindAllQuery<T extends PersistentRecord> extends Query<Lis
 
     protected List<T> resolve (Iterable<Key<T>> allKeys, Map<Key<T>, T> entities)
     {
-        List<T> result = new ArrayList<T>();
+        List<T> result = (allKeys instanceof Collection<?>)
+            ? Lists.<T>newArrayListWithCapacity(((Collection<?>)allKeys).size())
+            : Lists.<T>newArrayList();
         for (Key<T> key : allKeys) {
             T value = entities.get(key);
             if (value != null) {
@@ -310,12 +312,11 @@ public abstract class FindAllQuery<T extends PersistentRecord> extends Query<Lis
         // if we're fetching a huge number of records, we have to do it in multiple queries
         if (fetchKeys.size() > In.MAX_KEYS) {
             int keyCount = fetchKeys.size();
+            Iterator<Key<T>> iter = fetchKeys.iterator();
             do {
                 Set<Key<T>> keys = Sets.newHashSet();
-                Iterator<Key<T>> iter = fetchKeys.iterator();
-                for (int ii = 0; ii < Math.min(keyCount, In.MAX_KEYS); ii++) {
+                for (int ii = 0, nn = Math.min(keyCount, In.MAX_KEYS); ii < nn; ii++) {
                     keys.add(iter.next());
-                    iter.remove();
                 }
                 keyCount -= keys.size();
                 loadRecords(ctx, conn, keys, entities, origStmt);