separated ExprFactory into interface and implementation

querydsl-collections/src/main/java/com/mysema/query/collections/ExprFactory.java

@@ -0,0 +1,33 @@
+/*
+ * Copyright (c) 2008 Mysema Ltd.
+ * All rights reserved.
+ * 
+ */
+package com.mysema.query.collections;
+
+import com.mysema.query.grammar.types.ColTypes.ExtString;
+import com.mysema.query.grammar.types.Path.*;
+
+/**
+ * ExprFactory provides
+ *
+ * @author tiwe
+ * @version $Id$
+ */
+public interface ExprFactory {
+
+    PBoolean create(Boolean arg);
+
+    PBooleanArray create(Boolean[] args);
+
+    <D extends Comparable<D>> PComparable<D> create(D arg);
+
+    <D> PSimple<D> create(D arg);
+
+    <D extends Comparable<D>> PComparableArray<D> create(D[] args);
+
+    ExtString create(String arg);
+
+    PStringArray create(String[] args);
+
+}