few minor cleanups

git-svn-id: https://svn.code.sf.net/p/jackcess/code/jackcess/branches/mutateops@1001 f203690c-595d-4dc9-a70b-905162fa7fd2

src/main/java/com/healthmarketscience/jackcess/IndexBuilder.java

@@ -161,6 +161,12 @@ public class IndexBuilder
     _indexNumber = newIndexNumber;
   }
 
+  /**
+   * Checks that this index definition is valid.
+   *
+   * @throws IllegalArgumentException if this index definition is invalid.
+   * @usage _advanced_method_
+   */
   public void validate(Set<String> tableColNames, JetFormat format) {
 
     DatabaseImpl.validateIdentifierName(

src/main/java/com/healthmarketscience/jackcess/Relationship.java

@@ -45,6 +45,8 @@ public interface Relationship
   
   public boolean cascadeDeletes();
 
+  public boolean cascadeNullOnDelete();
+
   public boolean isLeftOuterJoin();
 
   public boolean isRightOuterJoin();