在代码上获取 ClassNotFoundException：“Class.forName(”com.microsoft.sqlserver.jdbc.SqlServerDriver“);”

Question

This is my first Java application and I'm completely inexperienced with Java and NetBeans .

I have been trying to connect to sql and get some records for 2 days. The problem is about jdbc driver, let me explain. I have downloaded sqljdbc driver and then followed these steps:

Right-click Project->Select Properties->On the left-hand side click Libraries->Under Compile tab - click Add Jar/Folder button and select sqljdbc4.jar file. Then it should be ok, right?

Then I wrote this code But I cant get rid of this exception:

  Exception in thread "main" java.lang.ClassNotFoundException: 
  com.microsoft.sqlserver.jdbc.SqlServerDriver
at java.net.URLClassLoader$1.run(URLClassLoader.java:366)
at java.net.URLClassLoader$1.run(URLClassLoader.java:355)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:354)
at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:308)
at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Class.java:190)
at javaapplication1.JavaApplication1.main(JavaApplication1.java:30)

This is the code

public static void main(String[] args) throws ClassNotFoundException, SQLException {
    String url = "jdbc:sqlserver://.\\SQLEXPRESS;databaseName=Northwind; Integrated Security = SSPI ";

    Connection con = null;
    Statement stmt = null;

    ResultSet rs = null;
    try {
        Class.forName("com.microsoft.sqlserver.jdbc.SqlServerDriver");

        con = DriverManager.getConnection(url);
        String sql = "Select Top 3 from * person.Contact";
        stmt = con.createStatement();
        rs = stmt.executeQuery(sql);
        while (rs.next()) {
            System.out.println(rs.getString(1));
        }
    } catch (Exception e) {
        e.printStackTrace();
    }
}

Answer 1

According to this page , the class is called SQLServerDriver and not SqlServerDriver . Case is important!

So, try:

Class.forName("com.microsoft.sqlserver.jdbc.SQLServerDriver");

Note that with newer versions of JDBC, it's not necessary to load the driver class explicitly with Class.forName(...) . The page I linked to explicitly explains that you don't have to do it. So, you can just remove the whole line and then it should work.

Answer 2

Java: JDBC Connectivity with MSSQL in NetBeans

Steps

1. Download JDBC from: https://www.microsoft.com/en-in/download/details.aspx?id=11774
2. Run sqljdbc__enu.exe - unpack this zip file in %Program Files (x86)% with the default directory: Microsoft JDBC DRIVER for SQL Server
3. Create your new project in NetBeans
4. Right Click on the project - select Properties - select Libraries from left panel - click Add JAR/Folder button - select your JAR file and open - ok
5. Open Sql Server Configuration Manager - select Protocols for SQLEXPRESS under Sql Server Network Configuration - Right Click on TCP/IP - select Properties - change Enable to Yes - Click IP Addresses - Goto IPAll - Change TCP Dynamic Ports to 49169 and TCP Port to 1433 - Apply - Ok - Restart the Computer
6. Open Run and type Services.msc - Start SQL Server Browser
7. Goto project and write code for database connectivity.

Code for Local Database Connectivity:

String url = "jdbc:sqlserver://YOUR PC NAME;instanceName=SQLEXPRESS;DatabaseName=dbname;integratedSecurity=true";

Class.forName("com.microsoft.sqlserver.jdbc.SQLServerDriver");
Connection myCon = DriverManager.getConnection(url);

Statement myStmt = myCon.createStatement();
ResultSet myRs = myStmt.executeQuery("select * from table name");

Answer 3

I have an update about this issue.

1. Go to this link, find your compatible JDBC driver (I dowloaded 6.0 version).
2. Find the appropriate jar in the file you downloaded (I used jre7\\sqljdbc41.jar).
3. For Intellij Idea press Ctrl+Shift+Alt+S and open Project Structure then in the dependencies section add your jar file.

I hope it works for you too.