From ec3e4127d2f5ee2bcd8e8cb1fd92953fbe0bb785 Mon Sep 17 00:00:00 2001
From: lukaseder <lukas.eder@gmail.com>
Date: Thu, 1 Jun 2017 12:23:00 +0200
Subject: [PATCH] [#6304] Improve internal TableAlias discovery

---
 .../java/org/jooq/impl/AbstractTable.java     | 16 ++---------
 .../java/org/jooq/impl/DeleteQueryImpl.java   |  7 ++---
 .../main/java/org/jooq/impl/JoinTable.java    | 28 +++++--------------
 jOOQ/src/main/java/org/jooq/impl/Tools.java   |  2 +-
 4 files changed, 13 insertions(+), 40 deletions(-)

diff --git a/jOOQ/src/main/java/org/jooq/impl/AbstractTable.java b/jOOQ/src/main/java/org/jooq/impl/AbstractTable.java
index 2df11c8451..ffc850b347 100644
--- a/jOOQ/src/main/java/org/jooq/impl/AbstractTable.java
+++ b/jOOQ/src/main/java/org/jooq/impl/AbstractTable.java
@@ -487,19 +487,9 @@ abstract class AbstractTable<R extends Record> extends AbstractQueryPart impleme
                 result.add((ForeignKey<R, O>) reference);
             }
 
-            // TODO: Refactor the following two blocks and make things more OO
-            // [#1460] In case the other table was aliased using
-            else if (other instanceof TableImpl) {
-                Table<O> aliased = ((TableImpl<O>) other).getAliasedTable();
-
-                if (aliased != null && aliased.equals(reference.getKey().getTable())) {
-                    result.add((ForeignKey<R, O>) reference);
-                }
-            }
-
-            // [#1460] In case the other table was aliased using
-            else if (other instanceof TableAlias) {
-                Table<O> aliased = ((TableAlias<O>) other).getAliasedTable();
+            // [#1460] [#6304] In case the other table was aliased
+            else {
+                Table<O> aliased = Tools.aliased(other);
 
                 if (aliased != null && aliased.equals(reference.getKey().getTable())) {
                     result.add((ForeignKey<R, O>) reference);
diff --git a/jOOQ/src/main/java/org/jooq/impl/DeleteQueryImpl.java b/jOOQ/src/main/java/org/jooq/impl/DeleteQueryImpl.java
index 9c68000e22..e4e14d130b 100644
--- a/jOOQ/src/main/java/org/jooq/impl/DeleteQueryImpl.java
+++ b/jOOQ/src/main/java/org/jooq/impl/DeleteQueryImpl.java
@@ -108,13 +108,10 @@ final class DeleteQueryImpl<R extends Record> extends AbstractDMLQuery<R> implem
         // DELETE t1 FROM my_table AS t1
         if (asList(MARIADB, MYSQL).contains(ctx.configuration().dialect())) {
 
-            // [#2579] TODO: Improve Table API to discover aliased tables more
-            // reliably instead of resorting to instanceof:
-            if (table instanceof TableAlias ||
-               (table instanceof TableImpl && ((TableImpl<R>) table).getAliasedTable() != null)) {
+            // [#2579] [#6304] TableAlias discovery
+            if (Tools.alias(table) != null)
                 ctx.visit(table)
                    .sql(' ');
-            }
         }
 
         ctx.visit(K_FROM).sql(' ')
diff --git a/jOOQ/src/main/java/org/jooq/impl/JoinTable.java b/jOOQ/src/main/java/org/jooq/impl/JoinTable.java
index 4ca2ad5469..ae9d6bbbf9 100755
--- a/jOOQ/src/main/java/org/jooq/impl/JoinTable.java
+++ b/jOOQ/src/main/java/org/jooq/impl/JoinTable.java
@@ -602,25 +602,10 @@ implements
 
     private final Table<?> search(Table<?> tree, Table<?> search) {
 
-        // TODO: Another instanceof, and we should probably resort to
-        //       implementing a new org.jooq.Context to traverse the AST
-        if (tree instanceof TableImpl) {
-            TableImpl<?> t = (TableImpl<?>) tree;
-
-            if (t.alias == null && search.equals(t))
-                return t;
-            else if (t.alias != null && search.equals(t.alias.wrapped()))
-                return t;
-            else
-                return null;
-        }
-        else if (tree instanceof TableAlias) {
-            TableAlias<?> t = (TableAlias<?>) tree;
-
-            if (search.equals(t.alias.wrapped()))
-                return t;
-            else
-                return null;
+        // [#6304] Improved alias discovery
+        Alias<? extends Table<?>> alias = Tools.alias(tree);
+        if (alias != null) {
+            return search(alias.wrapped(), search);
         }
         else if (tree instanceof JoinTable) {
             JoinTable t = (JoinTable) tree;
@@ -631,8 +616,9 @@ implements
 
             return r;
         }
-
-        return tree;
+        else {
+            return search.equals(tree) ? tree : null;
+        }
     }
 
     @SuppressWarnings({ "unchecked", "rawtypes" })
diff --git a/jOOQ/src/main/java/org/jooq/impl/Tools.java b/jOOQ/src/main/java/org/jooq/impl/Tools.java
index d39f037fef..c257307d06 100644
--- a/jOOQ/src/main/java/org/jooq/impl/Tools.java
+++ b/jOOQ/src/main/java/org/jooq/impl/Tools.java
@@ -3735,7 +3735,7 @@ final class Tools {
             return null;
     }
 
-    static final Alias<?> alias(Table<?> table) {
+    static final Alias<? extends Table<?>> alias(Table<?> table) {
         if (table instanceof TableImpl)
             return ((TableImpl<?>) table).alias;
         else if (table instanceof TableAlias)