JAVA-342: Converting array to List instead of vice versa using Arrays.asList(T ...), to avoid double copy

Author: jyemin

src/main/com/mongodb/DBApiLayer.java

@@ -23,6 +23,7 @@
 import org.bson.types.ObjectId;
 
 import java.util.ArrayList;
+import java.util.Arrays;
 import java.util.Collections;
 import java.util.HashMap;
 import java.util.Iterator;
@@ -196,28 +197,28 @@ public void drop(){
             super.drop();
         }
 
-        public WriteResult insert(DBObject[] arr, com.mongodb.WriteConcern concern, DBEncoder encoder ){
+        public WriteResult insert(List<DBObject> list, com.mongodb.WriteConcern concern, DBEncoder encoder ){
 
             if (concern == null) {
                 throw new IllegalArgumentException("Write concern can not be null");
             }
 
-            return insert( arr, true, concern, encoder );
+            return insert(list, true, concern, encoder);
         }
 
-        protected WriteResult insert(DBObject[] arr, boolean shouldApply , com.mongodb.WriteConcern concern, DBEncoder encoder ){
+        protected WriteResult insert(List<DBObject> list, boolean shouldApply , com.mongodb.WriteConcern concern, DBEncoder encoder ){
 
             if (encoder == null)
                 encoder = DefaultDBEncoder.FACTORY.create();
 
             if ( willTrace() ) {
-                for (DBObject o : arr) {
+                for (DBObject o : list) {
                     trace( "save:  " + _fullNameSpace + " " + JSON.serialize( o ) );
                 }
             }
 
             if ( shouldApply ){
-                for (DBObject o : arr) {
+                for (DBObject o : list) {
                     apply(o);
                     _checkObject(o, false, false);
                     Object id = o.get("_id");
@@ -231,12 +232,12 @@ protected WriteResult insert(DBObject[] arr, boolean shouldApply , com.mongodb.W
 
             int cur = 0;
             int maxsize = _mongo.getMaxBsonObjectSize();
-            while ( cur < arr.length ) {
+            while ( cur < list.size() ) {
 
                OutMessage om = OutMessage.insert( this , encoder, concern );
 
-               for ( ; cur<arr.length; cur++ ){
-                    DBObject o = arr[cur];
+               for ( ; cur < list.size(); cur++ ){
+                    DBObject o = list.get(cur);
                     om.putObject( o );
 
                     // limit for batch insert is 4 x maxbson on server, use 2 x to be safe
@@ -341,7 +342,7 @@ public void createIndex( final DBObject keys, final DBObject options, DBEncoder
             MyCollection idxs = DBApiLayer.this.doGetCollection( "system.indexes" );
             //query first, maybe we should do an update w/upsert? -- need to test performance and lock behavior
             if ( idxs.findOne( full ) == null )
-                idxs.insert( new DBObject[] { full },  false, WriteConcern.SAFE, encoder );
+                idxs.insert(Arrays.asList(full), false, WriteConcern.SAFE, encoder);
         }
 
         final String _fullNameSpace;

src/main/com/mongodb/DBCollection.java

@@ -19,9 +19,11 @@
 package com.mongodb;
 
 // Mongo
+
 import org.bson.types.ObjectId;
 
 import java.util.ArrayList;
+import java.util.Arrays;
 import java.util.Collections;
 import java.util.HashMap;
 import java.util.HashSet;
@@ -69,7 +71,9 @@ public WriteResult insert(DBObject[] arr , WriteConcern concern ){
      * @throws MongoException
      * @dochub insert
      */
-    public abstract WriteResult insert(DBObject[] arr , WriteConcern concern, DBEncoder encoder);
+    public WriteResult insert(DBObject[] arr , WriteConcern concern, DBEncoder encoder) {
+        return insert(Arrays.asList(arr), concern, encoder);
+    }
 
     /**
      * Inserts a document into the database.
@@ -83,7 +87,7 @@ public WriteResult insert(DBObject[] arr , WriteConcern concern ){
      * @dochub insert
      */
     public WriteResult insert(DBObject o , WriteConcern concern ){
-        return insert( new DBObject[]{ o } , concern );
+        return insert( Arrays.asList(o) , concern );
     }
 
     /**
@@ -140,9 +144,22 @@ public WriteResult insert(List<DBObject> list ){
      * @dochub insert
      */
     public WriteResult insert(List<DBObject> list, WriteConcern concern ){
-        return insert( list.toArray( new DBObject[list.size()] ) , concern );
+        return insert(list, concern, getDBEncoder() );
     }
 
+    /**
+     * Saves document(s) to the database.
+     * if doc doesn't have an _id, one will be added
+     * you can get the _id that was added from doc after the insert
+     *
+     * @param list list of documents to save
+     * @param concern the write concern
+     * @return
+     * @throws MongoException
+     * @dochub insert
+     */
+    public abstract WriteResult insert(List<DBObject> list, WriteConcern concern, DBEncoder encoder);
+
     /**
      * Performs an update operation.
      * @param q search query for old object to update