Program: 51155
Project: 51155
Buggy source:
private static String validateColumn(String column,String fieldName,Messages messages,MondrianGuiDef.Level l,JDBCValidator jdbcValidator,MondrianGuiDef.Cube cube,MondrianGuiDef.Hierarchy parentHierarchy){
  if (!isEmpty(column)) {
    if (jdbcValidator.isInitialized()) {
      String table=l.table;
      if (!isEmpty(table) && (parentHierarchy != null && parentHierarchy.relation instanceof MondrianGuiDef.Join)) {
        TreeSet joinTables=new TreeSet();
        SchemaExplorer.getTableNamesForJoin(parentHierarchy.relation,joinTables);
        if (!joinTables.contains(table)) {
          return messages.getString("String_Node_Str","String_Node_Str");
        }
      }
      if (isEmpty(table)) {
        if (parentHierarchy != null) {
          if (parentHierarchy.relation == null && cube != null) {
            if (!jdbcValidator.isColExists(((MondrianGuiDef.Table)cube.fact).schema,((MondrianGuiDef.Table)cube.fact).name,column)) {
              return messages.getFormattedString("String_Node_Str","String_Node_Str",new String[]{column});
            }
          }
 else           if (parentHierarchy.relation instanceof MondrianGuiDef.Table) {
            if (!jdbcValidator.isColExists(((MondrianGuiDef.Table)parentHierarchy.relation).schema,((MondrianGuiDef.Table)parentHierarchy.relation).name,column)) {
              return messages.getFormattedString("String_Node_Str","String_Node_Str",new String[]{isEmpty(column.trim()) ? "String_Node_Str" : column,fieldName,((MondrianGuiDef.Table)parentHierarchy.relation).name});
            }
          }
 else           if (parentHierarchy.relation instanceof MondrianGuiDef.Join) {
            return messages.getString("String_Node_Str","String_Node_Str");
          }
        }
      }
 else {
        if (parentHierarchy != null && parentHierarchy.relation instanceof MondrianGuiDef.Table && !isEmpty(table)) {
          return messages.getString("String_Node_Str","String_Node_Str");
        }
        if (parentHierarchy != null && parentHierarchy.relation instanceof MondrianGuiDef.Join) {
          table=SchemaExplorer.getTableNameForAlias(parentHierarchy.relation,table);
        }
        if (!jdbcValidator.isColExists(null,table,column)) {
          return messages.getFormattedString("String_Node_Str","String_Node_Str",new String[]{isEmpty(column.trim()) ? "String_Node_Str" : column,fieldName,table});
        }
      }
    }
  }
  return null;
}

Fixed version (ground truth):
private static String validateColumn(String column,String fieldName,Messages messages,MondrianGuiDef.Level l,JDBCValidator jdbcValidator,MondrianGuiDef.Cube cube,MondrianGuiDef.Hierarchy parentHierarchy){
  if (!isEmpty(column)) {
    if (jdbcValidator.isInitialized()) {
      String table=l.table;
      if (!isEmpty(table) && (parentHierarchy != null && parentHierarchy.relation instanceof MondrianGuiDef.Join)) {
        TreeSet<String> joinTables=new TreeSet<String>();
        SchemaExplorer.getTableNamesForJoin(parentHierarchy.relation,joinTables);
        if (!joinTables.contains(table)) {
          return messages.getString("String_Node_Str","String_Node_Str");
        }
      }
      if (isEmpty(table)) {
        if (parentHierarchy != null) {
          if (parentHierarchy.relation == null && cube != null) {
            if (!jdbcValidator.isColExists(((MondrianGuiDef.Table)cube.fact).schema,((MondrianGuiDef.Table)cube.fact).name,column)) {
              return messages.getFormattedString("String_Node_Str","String_Node_Str",new String[]{column});
            }
          }
 else           if (parentHierarchy.relation instanceof MondrianGuiDef.Table) {
            if (!jdbcValidator.isColExists(((MondrianGuiDef.Table)parentHierarchy.relation).schema,((MondrianGuiDef.Table)parentHierarchy.relation).name,column)) {
              return messages.getFormattedString("String_Node_Str","String_Node_Str",new String[]{isEmpty(column.trim()) ? "String_Node_Str" : column,fieldName,((MondrianGuiDef.Table)parentHierarchy.relation).name});
            }
          }
 else           if (parentHierarchy.relation instanceof MondrianGuiDef.Join) {
            return messages.getString("String_Node_Str","String_Node_Str");
          }
        }
      }
 else {
        if (parentHierarchy != null && parentHierarchy.relation instanceof MondrianGuiDef.Table && !isEmpty(table)) {
          return messages.getString("String_Node_Str","String_Node_Str");
        }
        if (parentHierarchy != null && parentHierarchy.relation instanceof MondrianGuiDef.Join) {
          table=SchemaExplorer.getTableNameForAlias(parentHierarchy.relation,table);
        }
        if (!jdbcValidator.isColExists(null,table,column)) {
          return messages.getFormattedString("String_Node_Str","String_Node_Str",new String[]{isEmpty(column.trim()) ? "String_Node_Str" : column,fieldName,table});
        }
      }
    }
  }
  return null;
}