This article is one of the series of Accessing Access 2007 on NetBeans 6.5 using JDBC. You can see the index of this series at Accessing Access 2007 on NetBeans 6.5 using JDBC, Part 1: Introduction

Perform SQL Operations

From Part 3: Create a Connection, I show how to create a connection from NetBeans 6.5 to the Northwind database of Microsoft Access 2007. On this post, you see how to perform basic SQL operations such as SELECT, INSERT, DELETE and UPDATE to the Customers table on Northwind database.

• Retrieve data from database
• Update data on database

Retrieve data from database

Copy and paste the code below on main method between these lines:

System.out.println("Connected!");

and

con.close();

The Code

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5
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7
8
9
10
11
12

            Statement stmt = null;
            ResultSet rs = null;
 
            // SQL query command
            String SQL = "SELECT * FROM Customers";
            stmt = con.createStatement();
            rs = stmt.executeQuery(SQL);
            while (rs.next()) {
                System.out.println(rs.getString("Company") + " : "
                        + rs.getString("First Name")+ " : "
                        + rs.getString("Last Name"));
            }

Code Explanation:

• Line 1-2: Declare some variables.
• Line 5: Define SQL query string.
• Line 6: Create a statement object for sending SQL statements to the database.
• Line 7: Executes the SQL statement and returns a single ResultSet object.
• Line 8-12: Iterative in the ResultSet object to show results on output window

Next, run the project. You see the result on the output window. It displays records from Customers table.

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Update data on database

To insert, update and delete records on MS Access 2007 databases, you can re-use the code from the previous section. But you need to replace the SQL statement and code on this line:

rs = stmt.executeQuery(SQL);
while (rs.next()) {
                System.out.println(rs.getString("Company") + " : "
                        + rs.getString("First Name")+ " : "
                        + rs.getString("Last Name"));
            }

to

int rowsEffected = stmt.executeUpdate(SQL);
System.out.println(rowsEffected + " rows effected");

Code Explanation:
Executes the given SQL statement which may be INSERT, UPDATE or DELETE statement and returns the row count for the update.

INSERT command

            // SQL INSERT command
            String SQL = "INSERT INTO Customers (Company,[First Name]," +
                    "[Last Name]) VALUES ('MyCompany','Linglom','My Last Name')";
            int rowsEffected = stmt.executeUpdate(SQL);
            System.out.println(rowsEffected + " rows effected");

UPDATE command

            // SQL UPDATE command
            String SQL = "UPDATE Customers SET [Last Name] = 'New Last Name'" +
                            "WHERE [First Name] = 'Linglom'";
            int rowsEffected = stmt.executeUpdate(SQL);
            System.out.println(rowsEffected + " rows effected");

DELETE command

            // SQL DELETE command
            String SQL = "DELETE FROM Customers WHERE [First Name] = 'Linglom'";
            int rowsEffected = stmt.executeUpdate(SQL);
            System.out.println(rowsEffected + " rows effected");

Summary

You can download the source code of this series at SampleAccess2007.java. The example code will create a connection to Northwind database on Microsoft Access 2007. Then, retrieve records, insert a new record, update and delete the record from Customer table. Here is output of the example code.

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Related posts:

1. Accessing MySQL on NetBeans using JDBC, Part II: Perform SQL Operations
2. Accessing SQL Server on NetBeans using JDBC, Part II: Perform SQL Operations
3. Accessing MS Access 2007 on NetBeans 6.5 using JDBC, Part 3: Create a Connection

This article is one of the series of Accessing MS Access 2007 on NetBeans 6.5 using JDBC. You can see the index of this series at Accessing Access 2007 on NetBeans 6.5 using JDBC, Part 1: Introduction

Create a Connection

From Part 2: Prepare Sample Database, I show how to setup Northwind database for Microsoft Access 2007. Now let’s start programming. On this post, you see how to create a connection from NetBeans 6.5 to the Northwind database of Microsoft Access 2007 which located at “c:\database\Northwind 2007.accdb”.

Step-by-step

1. Create a new Java Application project on NetBeans. Open NetBeans 6.5.1 and select File -> New Project.
   
2. On New Project, select Java -> Java Application. Click Next.
   
3. On New Java Application, type the project name “NorthwindSample” and click Finish.
   
4. The project “NorthwindSample” is created.
   
5. Let’s begin the programming part. First, I need to import some libraries.

   import java.sql.*;

   

6. Type the code below to the main method.

   1 2 3 4 5 6 7 8 9 10 11 12 13

   try { Class.forName("sun.jdbc.odbc.JdbcOdbcDriver"); String url = "jdbc:odbc:Driver={Microsoft Access Driver " + "(*.mdb, *.accdb)};DBQ=C:\\Database\\Northwind 2007.accdb"; Connection con = DriverManager.getConnection(url); System.out.println("Connected!"); con.close(); } catch (SQLException e) { System.out.println("SQL Exception: "+ e.toString()); } catch (ClassNotFoundException cE) { System.out.println("Class Not Found Exception: "+ cE.toString()); }

   Code Explanation:

   • Line 2: Class.forName(“sun.jdbc.odbc.JdbcOdbcDriver”); means load the JDBC-ODBC driver.
   • Line 3-4: String url = “jdbc:odbc:Driver={Microsoft Access Driver ” + “(*.mdb, *.accdb)};DBQ=C:\\Database\\Northwind 2007.accdb”; declare a variable which store a string of the driver name for Microsoft Access 2007 and the location of the Northwind database.
   • Line 5: Make a connection using information on the variable which was created before.
   • Line 6: Display “Connected!” on console window.
   • Line 7: Close the connection.

   

7. Compile and run the project. You see the text “Connected!” on the output window. Otherwise, you should see an exception message.
   

What’s Next?

Now you have connected to the Northwind database of Microsoft Access 2007. Next, I will show how to perform some basic SQL operations such as SELECT, INSERT, UPDATE and DELETE to the Northwind database. See Part 4: Perform SQL Operations.

Related posts:

1. Accessing SQL Server on NetBeans using JDBC, Part I: Create a connection
2. Accessing MS Access 2007 on NetBeans 6.5 using JDBC, Part 2: Prepare Sample Database
3. Accessing MS Access 2007 on NetBeans 6.5 using JDBC, Part 1: Introduction

This article is one of the series of Accessing MS Access 2007 on NetBeans 6.5 using JDBC. You can see the index of this series at Accessing Access 2007 on NetBeans 6.5 using JDBC, Part 1: Introduction

Prepare Sample Database

On this post, I show how to prepare a sample database for Microsoft Access 2007, the “Northwind” database.

Step-by-step

1. Open Microsoft Access 2007, click on Local Templates. If you have Northwind 2007 on Local Templates, click on it and skip to step 4. Otherwise, follow the next step to download one.
   
2. Download Northwind template for Access 2007 from Microsoft – Northwind 2007.
   
3. Extract the downloaded file, 01228997.cab. Then, double-click on 01228997.accdt. Microsoft Office Access 2007 will start.
   
4. On Microsoft Access, choose the destination to create a sample Northwind 2007. On this example, I choose “c:\database\Northwind 2007.accdb”. Then, click Create.
   
5. Now the sample Northwind database is created. Click on Navigation Pane on the left side menu.
   
6. On Navigation Pane, click on Supporting Objects and double-click on Customers. You see data in the Customers table.
   
7. You also see the sample database file on c:\database\Northwind 2007.accdb which was created on step 4. I will use this path in the later part.
   

What’s Next?

Now you have a sample database, Northwind. Next, I will show how to write code to create a connection from NetBeans 6.5 to the Northwind database. See Part 3: Create a Connection.

Related posts:

1. Accessing MS Access 2007 on NetBeans 6.5 using JDBC, Part 3: Create a Connection
2. Accessing MS Access 2007 on NetBeans 6.5 using JDBC, Part 1: Introduction
3. Accessing MS Access 2007 on NetBeans 6.5 using JDBC, Part 4: Perform SQL Operations

Introduction

Here comes again, a tutorial about accessing database on NetBeans. In 2007, I wrote two tutorials which are accessing SQL Server on NetBeans using JDBC and accessing MySQL on NetBeans using JDBC. Both tutorials are useful to many people so I decide to write a new one, Accessing MS Microsoft Access 2007 on NetBeans.

This series shows how to use NetBeans 6.5 to connect to a Microsoft Access 2007′s database using JDBC. After the connection is established, you see how to perform basic SQL operations such as SELECT, INSERT, UPDATE and DELETE on a table and get result (if any) to display on console window.

I divide this series into 4 parts:

1. Accessing MS Access 2007 on NetBeans 6.5 using JDBC, Part 1: Introduction
   The post that you are reading.
2. Accessing MS Access 2007 on NetBeans 6.5 using JDBC, Part 2: Prepare Northwind Database
   This post shows you how to prepare Northwind database of Microsoft Access 2007.
3. Accessing MS Access 2007 on NetBeans 6.5 using JDBC, Part 3: Create a Connection
   This post shows how to establish a connection to the Northwind database on NetBeans 6.5.
4. Accessing MS Access 2007 on NetBeans 6.5 using JDBC, Part 4: Perform SQL Operations
   This post shows how to perform basic SQL operations such as SELECT, INSERT, UPDATE and DELETE on Customer table on Northwind database.

Requirements

Here are the software requirements which I use on this series.

• NetBeans 6.5.1
• Northwind sample database for Microsoft Access 2007

Related posts:

1. Accessing MS Access 2007 on NetBeans 6.5 using JDBC, Part 3: Create a Connection
2. Accessing MS Access 2007 on NetBeans 6.5 using JDBC, Part 4: Perform SQL Operations
3. Accessing MS Access 2007 on NetBeans 6.5 using JDBC, Part 2: Prepare Sample Database

This post is the last part which gathers common problems along with solutions about accessing SQL Server using JDBC on NetBeans. By defer posting this a few months, I found many problems that may occur from many people and also solutions. So this post will benefit people who want to develop application to connect a SQL Server using JDBC and have problem with it.

There are 3 parts:

1. Part I : Create a connection
   This part which you’re reading shows about how to establish a connection between NetBeans and SQL Server. In this example, I use SQL Server 2000 SP4 and NetBeans IDE 5.5
2. Part II : Perform SQL Operations
   This part show how to perform some basic operations from NetBeans with SQL Server. For instance, send querys as SELECT, INSERT, UPDATE to the database.
3. Part III: Troubleshooting
   The last part is about problems and how to fix them.

Troubleshooting index

1. Missing the JDBC library
2. Mistype the connection string
3. The TCP/IP connection to the host has failed
4. Login failed for user ‘sa’
5. This driver is not configured for integrated authentication

1. Missing the JDBC library

Problem
You received this error message while compile code in part I.

Class Not Found Exception: java.lang.ClassNotFoundException: com.microsoft.sqlserver.jdbc.SQLServerDriver


Cause
This problem may have many causes as the following:

1. The JDBC library file is not loaded properly. You may not have add the library file “sqljdbc.jar” to the project.
2. You haven’t import the needed library to the project

Solution

1. Add the appropriate library to the project. Refer to part I: create a connection.
   
2. You need to add following code at the top of thesource code:
   import java.sql.Connection;
   import java.sql.DriverManager;
   import java.sql.SQLException;
   
   Or you can
   import java.sql.*;

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Problem
You received this error message while compile code in part I.

SQL Exception: java.sql.SQLException: No suitable driver found for jdbc:sqlserver:\\bkksql2005:1433;databaseName=AdventureWorks;user=sa;password=password;

Cause
You may have typed your connection string incorrectly so the JDBC driver couldn’t understand.

Solution
Recheck your connection string format. The format for SQL authentication mode should be
“jdbc:sqlserver://serverName:portNumber;databaseName=DatabaseName;user=UserName;password=Password;” where

• serverName is the name of the SQL Server
• (Optional) portNumber is the TCP port of SQL Server. Default port is 1433.
• (Optional) DatabaseName is the database name on SQL Server.
• UserName and Password are username and password for login to SQL Server. This user must be SQL Server authentication mode.

The format for Windows authentication mode should be
“jdbc:sqlserver://serverName:portNumber;databaseName=DatabaseName;integratedSecurity=true;” where

• serverName is the name of the SQL Server
• (Optional) portNumber is the TCP port of SQL Server. Default port is 1433.
• (Optional) DatabaseName is the database name on SQL Server.

Note: Database name is an optional. For more complex connection string, refer to MSDN – Building the Connection URL at Microsoft.

In this example, I mistype “jdbc:sqlserver://…” to “jdbc:sqlserver:\\…“.

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Problem
You received this error message while compile code in part I.

SQL Exception: com.microsoft.sqlserver.jdbc.SQLServerException: The TCP/IP connection to the host has failed. java.net.ConnectException: Connection refused: connect

Cause
You try to connect to a SQL Server which has not SQL Server service running or the service refuse to accept remote connections.

Solution

1. Recheck your connection string that you have type server name and port correctly or not.
2. Check that SQL Server is running.
3. If SQL Server is on remote host, try to check that you have allow remote connections on the server. To enable remote connections on SQL Server, try visit Enable remote connection to SQL Server 2005 Express.
4. Check firewall which may block the connection from client to server.

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Problem
You received this error message while compile code in part I.

SQL Exception: com.microsoft.sqlserver.jdbc.SQLServerException: Login failed for user ‘sa’.

Cause
This error message states clearly that you have provide wrong username or password that connect to SQL Server.

Solution
Recheck username and password again.

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Problem
You need to use Windows authentication mode by using ‘integratedSecurity=true’ instead of specify username and password in the connection string but receive this error message:

SQL Exception: com.microsoft.sqlserver.jdbc.SQLServerException: This driver is not configured for integrated authentication.
Feb 8, 2008 11:28:55 AM com.microsoft.sqlserver.jdbc.AuthenticationJNI
WARNING: Failed to load the sqljdbc_auth.dll

Cause
You need to add ‘sqljdbc_auth.dll’ to the system path. This file can be found in Microsoft SQL Server JDBC Driver. It resides in sqljdbc_1.1\enu\auth\x86 depends on your JDBC driver and system platform (x86 or x64).

Solution
Copy ‘sqljdbc_auth.dll’ to C:\Windows\System32
or
You can set the java.library.path to the directory where ‘sqljdbc_auth.dll’ is.

Note: If the path contains any spaces or special characters, you have to use double quotes “” around the value (ex. “your directory”).

Back to top

Related posts:

1. Accessing SQL Server on NetBeans using JDBC, Part I: Create a connection
2. Accessing SQL Server on NetBeans using JDBC, Part II: Perform SQL Operations
3. Accessing MySQL on NetBeans using JDBC, Part I: Create a connection

From Part I, I have only established a connection with local MySQL. Next I’ll show how to retrieve and modify data on remote MySQL.

MySQL Connection using in this part

Suppose that I have MySQL running remotely on IP:192.168.1.101 with default port (3306) and I want to connect to Northwind database with username is ‘root’ and password is ‘123456’. The connection string will be

String connectionUrl = "jdbc:mysql://192.168.1.101:3306/Northwind?" + 
            "user=root&password=123456";

Retrieve data from a database

To get some data, I need to execute query on the MySQL and get the result back to me. First, I create stmt (Statement object) and execute query in SQL language. Then I store the result on ResultSet object and iterative show the result on the output window.

            Statement stmt = null;
            ResultSet rs = null;
            //SQL query command
            String SQL = "SELECT * FROM Products";
            stmt = con.createStatement();
            rs = stmt.executeQuery(SQL);
            while (rs.next()) {
                System.out.println(rs.getString("ProductName") + " : " + rs.getString("UnitPrice"));
            }

Code Explanation:
- Statement objects allow you to execute basic SQL queries and retrieve the results through the ResultSet class.
- In while-loop, iterative in the ResultSet object to show result in console (ProductName and UnitPrice columns in Products table) on output window.

The example result will be similar to below.
Note: I have imported only 4 records from Products table in Northwind database.

Update data on database

To insert, update and delete records on SQL Server, you can use the code from retrieve data from database and simply change SQL command and also modify some code a little bit. On update, I must use executeUpdate(�?SQL�?) method on statement object instead executeQuery(“SQL�?) and the return value will be rows affected instead of a record set.

Example
INSERT command

            // SQL insert command
            String strSQL = "INSERT INTO Products (ProductName,QuantityPerUnit,UnitPrice,UnitsInStock,UnitsOnOrder," +
                            "ReOrderLevel,Discontinued) VALUES ('MyProduct','10 Kg.',1234.0000,100,50,30,0)";
            int rowsEffected = stmt.executeUpdate(strSQL);
            System.out.println(rowsEffected + " rows effected");

UPDATE command

            // SQL update command
            String strSQL = "UPDATE Products SET UnitPrice = 900, UnitsInStock = 55, UnitsOnOrder = 5 WHERE ProductName = 'MyProduct'";
            int rowsEffected = stmt.executeUpdate(strSQL);
            System.out.println(rowsEffected + " rows effected");

DELETE command

            // SQL delete command
            String strSQL = "DELETE FROM Products WHERE ProductName = 'MyProduct'");
            int rowsEffected = stmt.executeUpdate(strSQL);
            System.out.println(rowsEffected + " rows effected");

Summary

You can download source code example testMySQL.java (Right-click on the link and select Save target As…).
But you have to change connection string to match your environment. The example code will connect to Northwind database and try to retrieve records, insert a new record, update the record and delete the record from Products table. The result is below.

Related posts:

1. Accessing SQL Server on NetBeans using JDBC, Part II: Perform SQL Operations
2. Accessing MS Access 2007 on NetBeans 6.5 using JDBC, Part 4: Perform SQL Operations
3. Accessing MySQL on VB.NET using MySQL Connector/Net, Part VII: Perform SQL Operations

Introduction

This tutorial show you how to use NetBeans to connect MySQL by using MySQL Connector/J, MySQL AB’s JDBC Driver for MySQL.

I’ll divide into 2 parts:

1. Part I : Create a connection
   This part which you’re reading shows about how to establish a connection between NetBeans and MySQL.
2. Part II : Perform SQL Operations
   This part show how to perform some basic operations from NetBeans to MySQL. For instance, send querys as SELECT, INSERT, UPDATE to a database.

Requirements

• MySQL Connector/J, licensed under the GPL or a commercial license
  from MySQL AB.
• NetBeans with JRE (Java Runtime Environment).

Step-by-Step guide

1. Installation
   • Install NetBeans.
   • Download MySQL Connector/J, name ‘mysql-connector-java-5.0.6.zip’. (The file name may differs depends on the version if you’ve downloaded from the Official Site at here.)
   • Extract the zip file to a folder, you’ll see file ‘mysql-connector-java-5.0.6-bin.jar’ which is the library file that we want. Just copy the file to the library folder, for example to “C:\Program Files\Java\jdk1.6.0_02\lib” directory.
     
2. Add JDBC Driver to the project on NetBeans (Add a library).
   Next, I create a new Java project on NetBeans named ‘TestMySQL’ and add ‘mysql-connector-java-5.0.6-bin.jar’ that I’ve just extracted from previous step to the project’s library.
   1. Create New Project called TestSQL.
      
   2. In Projects window, right click the project name and select Properties.
      
   3. Project Properties window appears. The Categories on left side, select Libraries. And on right side in Compile tab, click Add JAR/Folder.
      
   4. New Window appears, browse to the file ‘mysql-connector-java-5.0.6-bin.jar’ and click Open.
      
   5. You’ll see the .jar file was added to the project. Click OK to finish.
      
      Note: You should keep mysql-connector-java-5.0.6-bin.jar in the directory that you won’t delete it (ex. not in temp folder). May be in the same directory that keep common library files. If you delete the file without delete a link from the project, the project will show error about missing library.
3. Connect to the database.
   Now I’m going to write some code to connect to MySQL database. I have configured MySQL service on localhost.
   1. I’m going to use Connection and DriverMapper Classes so I need to import libraries.
      import java.sql.*;
      
   2. I’ll connect to MySQL Server on local machine, the mysql database(a default database in MySQL). In main method, add the following code.

      try {  
                  Class.forName("com.mysql.jdbc.Driver");
                  String connectionUrl = "jdbc:mysql://localhost/mysql?" + 
                                         "user=root&password=123456";
                  Connection con = DriverManager.getConnection(connectionUrl);
              } catch (SQLException e) {
                  System.out.println("SQL Exception: "+ e.toString());
              } catch (ClassNotFoundException cE) {
                  System.out.println("Class Not Found Exception: "+ cE.toString());
              }

      The code explanation:

      • Class.forName(“com.mysql.jdbc.Driver”); means load the MySQL driver.
      • “jdbc:mysql://localhost/mysql?” + “user=root&password=123456″; is a connection string that tells to connect MySQL on localhost, select database named ‘mysql’ and user/password for MySQL server.
        If you would like to connecto to other database, simply change text ‘mysql’ after ‘localhost/’ to your database name.

      

   3. Compile and run the project. If no error occurs, it means that the connection has established successfully.
      

Next part, I’ll show to how to perform some basic SQL operations to MySQL.

Related posts:

1. Accessing SQL Server on NetBeans using JDBC, Part I: Create a connection
2. Accessing MS Access 2007 on NetBeans 6.5 using JDBC, Part 3: Create a Connection
3. Accessing MySQL on NetBeans using JDBC, Part II: Perform SQL Operations

From Part I, I have only established a connection with local SQL Server. Next I’ll show how to retrieve and modify data on remote SQL Server.

There are 3 parts:

1. Part I : Create a connection
   This part which you’re reading shows about how to establish a connection between NetBeans and SQL Server. In this example, I use SQL Server 2000 SP4 and NetBeans IDE 5.5
2. Part II : Perform SQL Operations
   This part show how to perform some basic operations from NetBeans with SQL Server. For instance, send querys as SELECT, INSERT, UPDATE to the database.
3. Part III: Troubleshooting
   The last part is about problems and how to fix them.

SQL Server Connection using in this part

Assume that I have SQL Server running remotely on BKKPDC01 computer and I want to connect to Northwind database with username is ‘sa’ and password is ‘password’. The connection string will be

String connectionUrl = "jdbc:sqlserver://bkkpdc01:1433;databaseName=Northwind;user=sa;password=password";

Retrieve data from database

To get some data, I need to execute query on the SQL Server and get the result back to me. First, I create stmt (Statement object) and execute query in SQL language. Then I store the result on ResultSet object and iterative show the result on the output window.

            Statement stmt = null;
            ResultSet rs = null;
            // SQL query command
            String SQL = "SELECT * FROM Products";
            stmt = con.createStatement();
            rs = stmt.executeQuery(SQL);
            while (rs.next()) {
                System.out.println(rs.getString("ProductName") + " : " + rs.getString("UnitPrice"));
            }

Code Explanation:
- Statement object is used for sending SQL Statement to the database.
- ResultSet object is used to keep data from the executed query.
- In while-loop, iterative in the ResultSet object to show result (All ProductName and UnitPrice in Products table) on output window.

The example result will be similar to below.

Update data on database

To insert, update and delete records on SQL Server, you can use the code from retrieve data from database and simply change SQL command and also modify some code a little bit. On update, I must use executeUpdate(�?SQL�?) method on statement object instead executeQuery(“SQL�?) and the return value will be rows affected instead of a record set.

Example
INSERT command

            // SQL query command
            String SQL = "INSERT INTO Products (ProductName,QuantityPerUnit,UnitPrice,UnitsInStock,UnitsOnOrder,ReOrderLevel,Discontinued) VALUES ('MyProduct','10 Kg.',1234.0000,100,50,30,0)";
            int rowsEffected = stmt.executeUpdate(SQL);
            System.out.println(rowsEffected + " rows effected");

UPDATE command

            // SQL query command
            String SQL = "UPDATE Products SET UnitPrice = 900, UnitsInStock = 55, UnitsOnOrder = 5 WHERE ProductName = 'MyProduct'";
            int rowsEffected = stmt.executeUpdate(SQL);
            System.out.println(rowsEffected + " rows effected");

DELETE command

            // SQL query command
            String SQL = "DELETE FROM Products WHERE ProductName = 'MyProduct'");
            int rowsEffected = stmt.executeUpdate(SQL);
            System.out.println(rowsEffected + " rows effected");

Summary

You can download the source code example here (Right-click on the link and select Save target As…).
But you have to change connection string to match your environment. The example code will connect to Northwind database and try to retrieve records, insert a new record, update the record and delete the record from Products table. The result is below.

Related posts:

1. Accessing MySQL on NetBeans using JDBC, Part II: Perform SQL Operations
2. Accessing MS Access 2007 on NetBeans 6.5 using JDBC, Part 4: Perform SQL Operations
3. Accessing MySQL on VB.NET using MySQL Connector/Net, Part VII: Perform SQL Operations

Have you ever confront a situation that you need to execute external programs while developing a Java application? For instance, you are developing a Java application and need to execute external application(another executable program) in the middle of the program or you may need to execute some commands such as listing directory command: dir (in windows) or ls (in Unix) while developing the program.

The following will show you how to execute the external program from Java application.

Example

Note: The example will use NetBeans as IDE.

Let see the example Java source code below:

 
import java.io.*;
 
public class Main {
 
       public static void main(String args[]) {
 
            try {
                Runtime rt = Runtime.getRuntime();
                //Process pr = rt.exec("cmd /c dir");
                Process pr = rt.exec("c:\\helloworld.exe");
 
                BufferedReader input = new BufferedReader(new InputStreamReader(pr.getInputStream()));
 
                String line=null;
 
                while((line=input.readLine()) != null) {
                    System.out.println(line);
                }
 
                int exitVal = pr.waitFor();
                System.out.println("Exited with error code "+exitVal);
 
            } catch(Exception e) {
                System.out.println(e.toString());
                e.printStackTrace();
            }
        }
}

The above Java’s code will try to execute the external program (helloworld.exe) and show output in console as exit code of the external program.

The sample external program, Helloworld.exe (Visual Basic)

Code Explanation:

Runtime rt = Runtime.getRuntime();
Process pr = rt.exec("c:\\helloworld.exe");

Create Runtime Object and attach to system process. In this example, execute the helloworld.exe.
If you want to execute some commands, just modify the string in the rt.exec(“….�?) to command that you want.
For instance, in the comment line; //Process pr = rt.exec(“cmd /c dir”);
Note: that you need to enter “cmd /c …�? before type any command in Windows.

int exitVal = pr.waitFor();
System.out.println("Exited with error code "+exitVal);

Method waitFor() will make the current thread to wait until the external program finish and return the exit value to the waited thread.

Output example

Process pr = rt.exec(“c:\\helloworld.exe”);

Process pr = rt.exec(“cmd /c dir”);

Summary

This is a simple code to execute external applications. If you want to call functions from other program (ex. C++, Visual Basic DLL), you need to use JNI (Java Native Interface) which you can find a nice tutorial at codeproject.com.
If you need more information, below are some sites that talk about executing external code.

For Java users

• Execute an external program – Real’s Java How-to.

  http://www.rgagnon.com/javadetails/java-0014.html

• When Runtime.exec() won’t – Java World.

  http://www.javaworld.com/javaworld/jw-12-2000/jw-1229-traps.html

• Trouble with Runtime.getRuntime().exec(cmd) on Linux – Java.

  http://www.thescripts.com/forum/thread16788.html

• Runtime.getRuntime().exec (Linux / UNIX forum at JavaRanch).

  http://saloon.javaranch.com/cgi-bin/ubb/ultimatebb.cgi?ubb=get_topic&f=13&t=001755

• Java’s Runtime.exec() and External Applications.

  http://www.ensta.fr/~diam/java/online/io/javazine.html

For C++ users

• How can I start a process?

  http://www.codeguru.com/forum/showthread.php?t=302501

• Executing programs with C(Linux).

  http://www.gidforums.com/t-3369.html

Related posts:

1. Get System Information on command-line mode

Introduction
Currently, I’m doing a Java Project that need some 3D image processing so I come across with VTK which is an open source consists of a C++ class library, and several interpreted interface layers including Tcl/Tk, Java, and Python. To use VTK in Java, I need to compile VTK for using with Java. I have found only a few website that related with this topic and hardly to get troubleshoot problems so I decided to write the tutorial.

What do you need?

1. VTK Source and Data.
   In the example, I used VTK Source 4.4.2 and Data 5.0.2. I’ve found that when compile Source 5.0.2 in VS .NET, I got some errors so I recommend as that I use.
2. CMake Cross Platform Make.
   In the example, I used CMake 2.4.6
3. Microsoft Visual Studio .NET 2003

Step-By-Step Guide

1. Extract VTK Source and Data. I extract VTK Source to C:\VTK and VTK Data to C:\VTK\VTKData.



2. Run CMake to make project for VS .NET 2003



3. Specify source code path as C:\VTK and build binaries to C:\VTK\Bin as figure below.
   You can choose place to keep Binaries elsewhere if you want.



4. Click Configure. New Window appears to let you choose which compiler you want CMake to build for. Select Visual Studio 7 .NET 2003. Click OK.



5. New Window appears to confirm new directory creation. Click OK. Wait few minutes.



6. When finished, there will be some attributes show in cache values in red. Change some attributes as figure below. Then Click Configure, again.
   BUILD_SHARED_LIBS = ON.
   VTK_DATA_ROOT = C:\VTK\VTKDAta (Where you extract VTKData).
   VTK_WRAP_JAVA = ON (To make library for Java)



7. When configured done, the color on attributes will change to gray. Now Click OK.



8. When finished, CMake will close itself automatically. Now let see C:\VTK\Bin, where you build Binaries to, you will see solution file (VTK.sln). Double-click it to run Visual Studio.



9. Change Solution Configuration to Release to make sure that the compiled libraries can be use on other machine.



10. Then, Click Start (Debug -> Start) or press F5 to compile the project. This step may takes up to 1-2 hours depends on your CPU.



11. There may be new window show about configurations are out of date, just ignore it by select Yes.



12. The Compile will finish when the output window show as below.



13. If there is a window as below, you can ignore it by Click Cancel.



14. Finish!. Now you get the compiled library files in C:\VTK\Bin\bin\release for DLL files and C:\VTK\Bin\java\vtk for Java Class files.




15. For DLL libraries in Release folder, you can use by add System path to the folder. My Computer -> Properties -> Advanced -> Environment Variables -> Edit on Path in System Variables. Insert directory where DLL files are.
    
16. For Java libraries in java\vtk\, you can use by compile them to .class file.

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