ANTLR Version 2.0

ANTLR Version 2.0

Installation

Step 1
Download antlr version 2 jar from maven repository. (e.g : antlr-2.7.7.jar)
Step 2

Create a antlr2 grammar file say vhdl.g

Step 3

Compile the vhdl.g file

Step 3a

java -cp  /usr/local/lib/antlr-2.7.7.jar antlr.Tool  vhdl.g

Step 3b

In step a, source code will be generated depending on target language.By default it would be java language if you have not explicitly given.

Step 4

Compile the source code from step 3

Step 4a

javac -cp /usr/local/lib/antlr-2.7.7.jar *.java

Step 5

Write java program to use the classes in step4 to parse grammar sample.

Source code generated after compiling grammar

Class files generated after compiling source code

Main program to read input from a file and print AST

import java.io.BufferedReader;

import java.io.File;

import java.io.FileReader;

import java.io.Reader;

import antlr.CommonAST;

public class Main {

 public static void main(String[] args) throws Exception {

  

  String fname = "arith.vhdl";

  System.out.println("Parsing: " + fname);

  Reader reader = new BufferedReader(new FileReader(new File(fname)));

  VhdlLexer lexer = new VhdlLexer(reader);

  VhdlParser parser = new VhdlParser(lexer);

  parser.design_file();

  CommonAST ast = (CommonAST) parser.getAST();

  System.out.println(ast.toStringList());

 }

}

Maven Project Structure

Creating Maven Project

We will create maven project using two ways:

1) Using command line in CMD (command prompt) in windows

2) Using eclipse maven plug-in in eclipse

1) Creating a Maven project using command line

We need following command

mvn

Using mvn command along with other attributes

mvn archetype:generate  -DgroupId={ project-packaging }  -DartifactId={ project-name }

 -DarchetypeArtifactId=maven-archetype-webapp  -DinteractiveMode=false

We will create our maven project using our own values for attributes DgroupId , DartifactId , DarchetypeArtifactId

mvn archetype:generate -DgroupId=mavenproject -DartifactId=myproject -DarchetypeArtifactId=maven-archetype-webapp -DinteractiveMode=false 

Press enter to execute above command

Our maven project has been successfully created.

Depending on which IDE used for development, import the project and start working with your project.

We will import the project created in eclipse using following steps:

1) Go to File and click on import

2) Type maven, select Existing Maven Projects and click Next

3) Click on browse, search for the project on drive where generated and click ok

4) Once imported click on Finish to complete

5) We can see the imported project. Although its been created successfully, some folder have not been created. We will create them in following steps

6) Right Click on the project, Go to properties, Click on Java Build path .At right select on source tab.

7) Select entries marked with red box with cross symbol and clicks remove one by one.

8) After removing we can see as below

9) Creating java folder under main folder

a) Click Add Folder

b) Select main folder

c) Click on create new folder

d)  Type java under Folder name

e) Click on Finish

            f) java folder in now created under main folder

10) Create test folder under src folder

11) Create java folder under test folder

12) Now the whole maven project structure has been created as shown below

2) Creating a Maven project using Eclipse Maven plug-in

 a) Go to File, then new, and then other...

b) Search by typing maven, select Maven Project and Click Next

c) Click Next

d) Select Internal under Catalog, Filter using webapp

Select maven-archetype-webapp from artifact Id column in filtered list

e) Enter

Group Id = mavenproject

Artifact Id = myproject

Package = com.hh

Keep version as it’s, not compulsory to change

Click on Finish

f) Maven project has been created successfully in eclipse

g) If you check the maven structure, the newly created project structure is not exactly like the maven structure as shown in maven structure image.

Please create other folders required as directed under Topic Create maven project using command line.

installing maven in windows

Dowload maven any version (currently we are using 2.0.11) from web.

1) Download zip file of maven and extract to some folder on your drive as shown below

2) Setting maven in environment variable

3) Create Environment Variable MAVEN_PATH as shown

Press windows key + Pause/Break (shortcut key)

4) Add maven bin path to path environment variable

Press windows key + Pause/Break (shortcut key)

5) Check if maven is installed in windows

Open new command prompt (don’t use already opened command prompt)

Type mvn in command prompt

6) Maven installed successfully using environment variable.

Installing Maven in Eclipse

Two ways of installing maven in eclipse are

1) Using Eclipse Marketplace

2) Using Install new software

Web Services as we know are of two types

1. SOAP Web Service

 Here for examples we use WSDL as form of communication between Server and Client.
 Data trasferred between server and client as xml data.

2. REST Web Service

Here there is no WSDL Concept. 
Data transferred between server and client as json data.

Both makes us communicate when technologies of server and client differ or may be same.
Nowdays REST Web Service is being commonly used. 

It is much faster compared to SOAP in following ways.

a) Everytime we add a web method , we need to take care of wsdl which need to be send to client.
b) We tend to make mistake in generating wsdl.
c) Android developers face lot of difficulty in using SOAP Web Service.
d) With REST Web Service and its json support , makes data trasfer from android to Server easy and less time consuming.
e) Just need to create POJO classes for data transfer. 
f) Good use of Annotations , makes developing server side code easy and at a much faster pace.

Reading Arabic Data from MS Access Database

Reading Arabic Data from MS Access Database 

Reading and writing data to/from Ms Access Database can be done using JDBC , Hibernate etc frameworks.

Problem: I had a requirement of reading arabic data from ms access database. We tried using hibernate , jdbc .Reading other  than arabic data could be read easily done using hibernate and jdbc .

But for reading Arabic Data is difficult in JDBC and Hibernate . It mostly gives ????? for Arabic data.That means for UTF-8 it was not possible for me . So we went for JACKCESS.

We could use  JACKCESS to read Arabic data for MS Access Database. 

Jackcess is a pure Java library for reading and writing MS Access databases. It provides a robust, cross-platform backend API allowing other developers to integrate MS Access support into their Java applications

Create a  dynamic web project in java.

Download Following Jars :

 jackcess-1.2.9.jar commons-lang-2.2.jar commons-logging-1.1.1.jar

Put the above jars in your lib folder.

Create a database in microsoft acces with following detail.

Say  a database Name TestDatabase and in it a

table name user .

I have three columns id , name and age .

Now to access the data i have the following code sample :

package com.MSaccessArabicData;

import java.io.File;
import java.util.Map;
import com.healthmarketscience.jackcess.Database;
import com.healthmarketscience.jackcess.Table;
public class MsDatabaseAccess {
 public static void main(String[] args) {
  try {
   Table table = Database
     .open(new File(
       "D:\\TestDatabase.mdb"))
     .getTable("user");
   for (Map row : table) {

    String name = (String) row.get("name");

    int age = (Integer) row.get("age");
    
   }

  } catch (Exception e) {
   e.printStackTrace();
  }
 }
}

Documentation for jackcess is available here.

Using Hibernate Synchronizer Tool in Eclipse

Using Hibernate Synchronizer Tool in Eclipse

This tool is used to generate hibernate mapping xml directly from database tables. This is a reverse engineering process where in we directly use database tables to generate so called hbm files. 

Installing it in eclipse 

To use this tool download hibernate synchronizer from following location:

download hibernate synchronizer

Extract the zip file to plugins folder of you eclipse .
Then restart your eclipse .

Then go to windows then to preference.

You will see the hibernate synchronizer option at the left highlighted.

Using it in project

Now go to eclipse and create a project using  File then New and then  Dynamic Web project.


Add mysql jdbc jar to the lib folder of your project.

Now right click your project src folder and create a package say com.lara

Next right click lara folder and go to new then  other and then hibernate mapping file.

suppose following is the database server

suppose following is the database configuration in mysql server .

Container : the folder in which hbm xml needs to be gernerated.

Driver      : the mysql driver class name.

URL         : the url to connect to database . Here test is my database name

Username : mysql username 

password  : mysql password


Table       : select the table to generate Hibernate mapping file .

package   : the package name in here is com.lara . This will be specified in  hbm file generated

and click Finish.

Your hibernate mapping file will be generated inside lara folder.

Generate pojo classes from the hibernate mapping file

Right click the hbm file (eg user.hbm.xml in this case) then Hibernate synchronizer and then synchronize and overwrite as shown below

The java classes will be generated as shown below:

In addition two classes will be generate , one named User in your lara folder and the setters and getters in Base User under base folder in lara package.

Now you can directly use you User class in hibernate for database access.

SOURCE CODE  download from here