MDELite Installation and Overview Manual

• Storing models and metamodels as obscure XML documents, MDELite  encodes them as readable relational database text files; 
• Using Object Constraint Language (OCL) to express constraints, MDELite uses relational algebra operations written in Java;
• Writing Model-to-Model (M2M) transformations using customized MDE languages, MDELite relies on relational algebra operations written in Java; and
• Using yet another language/tool for Model-to-Text (M2T) and Text-to-Model (T2M) transformations, MDELite again relies on Java.  

• Installation of MDELite
• Basics of MDELite-Relational Schemas
• Basics of MDELite-Relational Databases
• Overview of MDELite Tools
• Closing Thoughts
  

Installation of MDELite

Docs -- documentation, including this manual, lib -- a library of jar files needed by MDELite, libpl -- a library of predefined schemas, and MDELite.jar -- the MDELite jar.

> set CLASSPATH=%CLASSPATH%;C:\xfer\dist\MDELite.jar

Violet should be running now.
If not, something is wrong.
Otherwise, please close Violet,
and MDELite Ready to Use! 

MDELite-Relational Schemas

oodb(school,[person,professor,department,student]).

table(person,[id,"name"]).
table(professor,[deptid]).
table(department,[id,"name","building"]).
table(student,[utid]).

subtable(person,[professor,student]). 

• The name of this schema is school.  It contains four tables: person, professor, department, student;
• Every table has a name and a list of columns (attributes). The person table has two attributes: id and "name''; and
• Tables can be arranged in an inheritance hierarchy.  The subtable declaration says professor and student are subtables of person.

1. The first attribute of every MDELite table is an identifier column whose name need not be "id";
2. There are two kinds of fields in MDELite table schemas: those with unquoted attribute names and those with quoted names. A quoted-name field means that all of its values must be quoted (single-or-double); an unquoted-name field means that all of its values must be unquoted;
3. An n-tuple of a table t is written as a Prolog fact: t(v1 ... vn).  Some person tuples might be:  

person(p1,'Don').
person(p2,'Barack Obama').
person(p3,"Ms Piggy").

> java MDELite.OO2DBSchema school.ooschema.pl

(silently produces school.schema.pl)

> type school.schema.pl

dbase(school,[person,professor,department,student]).

table(person,[id,"name"]).
table(professor,[id,"name",deptid]).
table(department,[id,"name","building"]).
table(student,[id,"name",utid]).

subtable(person,[professor,student]). 

New Additions to MDELite Schemas

table(Person,[id,name,worksin]).
table(Department,[id,name]).

table(Person, [id:string,name:string,worksin:Department]).
table(Department,[id:int,name:string]).

table(Person[id:string,name:string,worksin : optional Department]).

abs_table(Person,[id:string,name:string,worksin : optional Department]).

MDELite-Relational Databases

dbase(school,[person,professor,department,student]).

abs_table(person,[id,"name"]).

table(professor,[id,"name",deptid]).
professor(p1,'don',d1).
professor(p2,'Robert',d1).
professor(p3,'Lorenzo',d2).
professor(p4,'kelly',d3).

table(department,[id,"name","building"]).
department(d1,'computer science','gates dell complex').
department(d2,'computer science','gates hall').
department(d3,'computer science','Bahen Centre').

table(student,[id,"name",utid]).
student(s1,'zeke','zh333').
student(s2,'Brenda','UTgreat').
student(s3,'Thomas','astronaut201').

subtable(person,[professor,student]). 

• The student table has 3 tuples, department has 3 tuples, and professor has 4.
• person has 0 (no) explicit tuples because it was declared abstract.  This is like Java: objects/tuples are listed for the class/table in which they were created.  The tuples of person are the union of the tables of it and its subtables.
• The database schema definition is always included in a database file (that's the dbase fact).
• The schema definition for each table is always included in a database file (that's the table facts).
• The tuples of the table follow (not necessarily immediately) after its table fact.  An absence of tuple declarations says the table is empty.
• Note: a difference between an OO schema and the MDELite schema/database file is the first line.  An OO schema starts with "oodb name." whereas a database schema/file starts with "dbase name."  You can see this above in the discussion of the OO2DBSchema tool.
  

>java MDELite.InstOf my.school.pl school.schema.pl

MDELite Tools

• All
• CD2OOSchema
  
• Catalina
• Conformance
  
• InstOf
• MDETool (same as Catalina)
  
• Model-to-Model Transformations
• OOSchema to Schema Translation
• Reading Databases
• Reading Schemas
• Reading Tables
  
• Verify Install
  
• Version
• Violet Tools
• Yuml Tools

All

> java MDELite.All

CD2OOSchema

> java MDELite.CD2OOSchema school.class.violet

(produces school.ooschema.pl)

InstOf

> java MDELite.InstOf

Usage: MDL.InstOf S.schema.pl Y.S.pl
       confirms that database Y is an instance of S 

Catalina (a.k.a. MDETool)

> java MDELite.Catalina
or
> java MDELite.MDETool

Usage: Boot.MDELite.catalina option args...
       all               state -> java
       validateViolet    state -> T/F
       validateMeta      state -> meta
       quick             meta -> java 

Conformance

• Person Name Constraint: A Person's name must begin with a capital letter.
• Name Uniqueness: No two Person tuples have the same name

package BuildDocumentation;

import PrologDB.*;

public class schoolConform {

    public static void main(String... args) {
        // Step 1: standard command-line processing
        MDLUtilities.Marquee4Conform mark = new MDLUtilities.Marquee4Conform(schoolConform.class, ".school.pl", args);
        String inputFileName = mark.getInputFileName();
        String AppName = mark.getAppName();  
             // if "X.school.pl" is input database name
             // then AppName = "X"

        // Step 2: open database to be validated + get needed tables
        DB db = DB.read(inputFileName);
        Table person = db.getTableEH("person");
        ErrorReport er = new ErrorReport();

        // Step 3: now perform database checks
        
        // 3a. Person Name Constraint
        person.select(t -> checkCharacter(t))
                .forEach(t -> er.add("Person name not capitalized: %s", t.get("name")));

        // 3b. Name Uniqueness Contraint
        person.select(t -> person.select(g -> g.get("name").equals(t.get("name"))).count() > 1)
                .forEach(t -> er.add("Persons with duplicate name : %s" + t.get("name")));

        // print error report 
        er.print(System.out);
    }
    
    static boolean checkCharacter(Tuple t) {
        String n = t.get("name");
        if (n.length() == 0) {
            return true;
        }
        Character c = n.charAt(0);
        return Character.isLowerCase(c);
    }
} 

Person name not capitalized: don
Person name not capitalized: kelly
Person name not capitalized: zeke 

Model to Model (M2M) Transformations

OOSchema

> java MDELite.OO2DBSchema

Usage: MDL.OO2DBSchema X.ooschema.pl [X.schema.pl]
       translate X.ooschema.pl to X.schema.pl 

Reading a Database

> java MDELite.ReadDB

Usage: MDL.ReadDB X.pl 

Reading a Schema

> java MDELite.ReadSchema

Usage: MDL.ReadSchema .ooschema or schema.pl
       reads ooschema or schema X and reports errors 

Reading a Table

> java MDELite.ReadTable

Usage: MDL.ReadTable .
        is .csv or .pl
       reads table  and reports errors 

Verify Install

> java MDELite.VerifyInstall

Violet should be running now.
If not, something is wrong.
Otherwise, please close Violet,
and MDELite Ready to Use! 

Version

 > java MDELite.Version

 MDELite version 26 JUNE 2019 

Violet and its MDELite Tools

> java MDELite.Violet      // spawns Violet and waits for Violet to close

• Violet Class Parser
• Violet Class UnParser
• Violet Class Conform
• Violet State Tools

Violet Class Parser

% Violet (vpl) class database

dbase(vpl,[vBox,vAssociation]).

% type = c(class),i(nterface),n(ote).  packages are skipped
% abst : if type==c, is class abstract?
% abstract class names are prefaced by "Abs_"

table(vBox,[id,type,"name","fields","methods",abst:bool,x,y]).

% type* = c(lass) or i(nterface)
% lineStyle = ""(solid) or "DOTTED"
% arrow1,2 = V, TRIANGLE, DIAMOND, BLACK_DIAMOND
% bentStyle = "", HV, VH, HVH, VHV
% abst -- if type==c, is class abstract?

table(vAssociation,[id,cid1:vBox,type1,"role1","arrow1",cid2:vBox,type2,"role2","arrow2","bentStyle","lineStyle","middleLabel"]). 

> java Violett.ClassParser

Usage: Violett.ClassParser X.class.violet [X.vpl.pl]
       translate X.class.violet to X.vpl.pl 

Violet Class UnParser

> java Violett.ClassUnParser

Usage: Violett.ClassUnParser X.vpl.pl [X.class.violet]
       translate X.vpl.pl to X.class.violet 

Violet Class Conform

>java Violett.ClassConform

Usage: Violett.ClassConform X.vpl.pl
       evaluate conformance rules on X.vpl.pl
       silent return indicates no errors 

Violet State Tools

% violet (fsm) state machine database

dbase(fsm,[node,edge]).

% ntype = state | note | init | final | point
% etype = arrow | note

table(node,[nid,ntype,"text","color",xpos,ypos]).
table(edge,[eid,etype,"label",startid,endid]). 

Yuml and its MDELite Tools

% yuml class schema

dbase(ypl,[yumlBox,yumlAssociation]).

% type = n (for note), c (for class), i (for interface)
% abst : if type==c, is the class abstract? 
% abstract class names are prefaced by "Abs_"

table(yumlBox,[id,type,"name","fields","methods",abst:bool]).

% end1 = <> | ++ | ^ | < | "" (nothing)
% end2 = <> | ++ | ^ | > | "" (nothing)
% lineType = - | -.-

table(yumlAssociation,[id,box1,"role1","end1","lineType",box2,"role2","end2"]). 

Closing