bug fixed for oracle sql parser

src/main/java/com/alibaba/druid/sql/ast/statement/SQLExprTableSource.java

@@ -18,7 +18,7 @@ package com.alibaba.druid.sql.ast.statement;
 import com.alibaba.druid.sql.ast.SQLExpr;
 import com.alibaba.druid.sql.visitor.SQLASTVisitor;
 
-public class SQLExprTableSource extends SQLTableSource {
+public class SQLExprTableSource extends SQLTableSourceImpl {
 
     private static final long serialVersionUID = 1L;
 

src/main/java/com/alibaba/druid/sql/ast/statement/SQLJoinTableSource.java

@@ -18,7 +18,7 @@ package com.alibaba.druid.sql.ast.statement;
 import com.alibaba.druid.sql.ast.SQLExpr;
 import com.alibaba.druid.sql.visitor.SQLASTVisitor;
 
-public class SQLJoinTableSource extends SQLTableSource {
+public class SQLJoinTableSource extends SQLTableSourceImpl {
 
     private static final long serialVersionUID = 1L;
 

src/main/java/com/alibaba/druid/sql/ast/statement/SQLSetStatement.java

@@ -31,6 +31,10 @@ public class SQLSetStatement extends SQLStatementImpl {
 
     public SQLSetStatement(){
     }
+    
+    public SQLSetStatement(SQLExpr target, SQLExpr value) {
+        this.items.add(new Item(target, value));
+    }
 
     public List<Item> getItems() {
         return items;

src/main/java/com/alibaba/druid/sql/ast/statement/SQLSubqueryTableSource.java

@@ -17,7 +17,7 @@ package com.alibaba.druid.sql.ast.statement;
 
 import com.alibaba.druid.sql.visitor.SQLASTVisitor;
 
-public class SQLSubqueryTableSource extends SQLTableSource {
+public class SQLSubqueryTableSource extends SQLTableSourceImpl {
 
     private static final long serialVersionUID = 1L;
 

src/main/java/com/alibaba/druid/sql/ast/statement/SQLTableSource.java

@@ -1,42 +1,10 @@
-/*
- * Copyright 1999-2011 Alibaba Group Holding Ltd.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *      http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
 package com.alibaba.druid.sql.ast.statement;
 
-import com.alibaba.druid.sql.ast.SQLObjectImpl;
+import com.alibaba.druid.sql.ast.SQLObject;
 
-public abstract class SQLTableSource extends SQLObjectImpl {
+public interface SQLTableSource extends SQLObject {
 
-    private static final long serialVersionUID = 1L;
+    String getAlias();
 
-    protected String          alias;
-
-    public SQLTableSource(){
-
-    }
-
-    public SQLTableSource(String alias){
-
-        this.alias = alias;
-    }
-
-    public String getAlias() {
-        return this.alias;
-    }
-
-    public void setAlias(String alias) {
-        this.alias = alias;
-    }
+    void setAlias(String alias);
 }

src/main/java/com/alibaba/druid/sql/ast/statement/SQLTableSourceImpl.java

@@ -0,0 +1,42 @@
+/*
+ * Copyright 1999-2011 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.alibaba.druid.sql.ast.statement;
+
+import com.alibaba.druid.sql.ast.SQLObjectImpl;
+
+public abstract class SQLTableSourceImpl extends SQLObjectImpl implements SQLTableSource {
+
+    private static final long serialVersionUID = 1L;
+
+    protected String          alias;
+
+    public SQLTableSourceImpl(){
+
+    }
+
+    public SQLTableSourceImpl(String alias){
+
+        this.alias = alias;
+    }
+
+    public String getAlias() {
+        return this.alias;
+    }
+
+    public void setAlias(String alias) {
+        this.alias = alias;
+    }
+}