improved support hints.

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

@@ -15,9 +15,12 @@
  */
 package com.alibaba.druid.sql.ast.statement;
 
+import com.alibaba.druid.sql.ast.SQLCommentHint;
 import com.alibaba.druid.sql.ast.SQLDataTypeImpl;
 import com.alibaba.druid.sql.visitor.SQLASTVisitor;
 
+import java.util.List;
+
 public class SQLCharacterDataType extends SQLDataTypeImpl {
 
     private String             charSetName;
@@ -26,6 +29,8 @@ public class SQLCharacterDataType extends SQLDataTypeImpl {
     private String             charType;
     private boolean            hasBinary;
 
+    public List<SQLCommentHint> hints;
+
     public final static String CHAR_TYPE_BYTE = "BYTE";
     public final static String CHAR_TYPE_CHAR = "CHAR";
 
@@ -65,6 +70,14 @@ public class SQLCharacterDataType extends SQLDataTypeImpl {
         this.charType = charType;
     }
 
+    public List<SQLCommentHint> getHints() {
+        return hints;
+    }
+
+    public void setHints(List<SQLCommentHint> hints) {
+        this.hints = hints;
+    }
+
     @Override
     protected void accept0(SQLASTVisitor visitor) {
         if (visitor.visit(this)) {

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

@@ -15,18 +15,33 @@
  */
 package com.alibaba.druid.sql.ast.statement;
 
+import com.alibaba.druid.sql.ast.SQLCommentHint;
 import com.alibaba.druid.sql.ast.SQLName;
 import com.alibaba.druid.sql.ast.SQLObjectImpl;
 
+import java.util.List;
+
 public abstract class SQLConstraintImpl extends SQLObjectImpl implements SQLConstraint {
 
     private SQLName name;
     private Boolean enable;
 
+    public List<SQLCommentHint> hints;
+
     public SQLConstraintImpl(){
 
     }
 
+
+    public List<SQLCommentHint> getHints() {
+        return hints;
+    }
+
+    public void setHints(List<SQLCommentHint> hints) {
+        this.hints = hints;
+    }
+
+
     public SQLName getName() {
         return name;
     }

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

@@ -15,10 +15,15 @@
  */
 package com.alibaba.druid.sql.ast.statement;
 
+import com.alibaba.druid.sql.ast.SQLCommentHint;
 import com.alibaba.druid.sql.visitor.SQLASTVisitor;
 
+import java.util.List;
+
 public class SQLNotNullConstraint extends SQLConstraintImpl implements SQLColumnConstraint {
 
+
+
     public SQLNotNullConstraint(){
 
     }