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ClassNotFoundException when running sample MySQL code in eclipse

I'm trying to compile and run the sample code shown below, but it gives me a ClassNotFoundException. I was wondering what the best way to resolve this issue in eclipse would be, as I'm new to the software. I've read many answers on the site about this exception and what may cause it, but I cannot understand alot of the solutions, so I would greatly appreciate if someone could give me a simple explanation for what's causing the problem. Thank you.
public class Model{
public static void main(String[] args) throws Exception
{
Model myDbTest = new Model();
myDbTest.displayDbProperties();
}
private java.sql.Connection con = null;
private final String url = "jdbc:microsoft:sqlserver://";
private final String serverName= "localhost";
private final String portNumber = "1433";
private final String databaseName= "pubs";
private final String userName = "user";
private final String password = "password";
// Informs the driver to use server a side-cursor,
// which permits more than one active statement
// on a connection.
private final String selectMethod = "cursor";
// Constructor
public Model(){}
private String getConnectionUrl(){
return url+serverName+":"+portNumber+";databaseName="+databaseName+";selectMethod="+selectMethod+";";
}
private java.sql.Connection getConnection(){
try{
Class.forName("com.microsoft.jdbc.sqlserver.SQLServerDriver");
con = java.sql.DriverManager.getConnection(getConnectionUrl(),userName,password);
if(con!=null) System.out.println("Connection Successful!");
}catch(Exception e){
e.printStackTrace();
System.out.println("Error Trace in getConnection() : " + e.getMessage());
}
return con;
}
/*
Display the driver properties, database details
*/
public void displayDbProperties(){
java.sql.DatabaseMetaData dm = null;
java.sql.ResultSet rs = null;
try{
con= this.getConnection();
if(con!=null){
dm = con.getMetaData();
System.out.println("Driver Information");
System.out.println("\tDriver Name: "+ dm.getDriverName());
System.out.println("\tDriver Version: "+ dm.getDriverVersion ());
System.out.println("\nDatabase Information ");
System.out.println("\tDatabase Name: "+ dm.getDatabaseProductName());
System.out.println("\tDatabase Version: "+ dm.getDatabaseProductVersion());
System.out.println("Avalilable Catalogs ");
rs = dm.getCatalogs();
while(rs.next()){
System.out.println("\tcatalog: "+ rs.getString(1));
}
rs.close();
rs = null;
closeConnection();
}else System.out.println("Error: No active Connection");
}catch(Exception e){
e.printStackTrace();
}
dm=null;
}
private void closeConnection(){
try{
if(con!=null)
con.close();
con=null;
}catch(Exception e){
e.printStackTrace();
}
}
}
The error is printed as:
java.lang.ClassNotFoundException: com.microsoft.jdbc.sqlserver.SQLServerDriverError Trace in getConnection() : com.microsoft.jdbc.sqlserver.SQLServerDriver
Error: No active Connection
at java.net.URLClassLoader$1.run(Unknown Source)
at java.net.URLClassLoader$1.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Unknown Source)
at Model.getConnection(Model.java:30)
at Model.displayDbProperties(Model.java:48)
at Model.main(Model.java:6)

It looks like the JAR of your JDBC driver is not included in the classpath when running your source code. But as others mentioned, stacktrace is probably needed to further help you.

It looks like you haven't MsSQLServer jdbc driver in your .classpath
Look here

“java.lang.ClassNotFoundException” when executing Java code when running in terminal [duplicate]

I was trying to make connection with Oracle 11g via java and i have added ojdbc14 and ojdbc6 but still i am getting this error while compiling.Please help.
java.lang.ClassNotFoundException: com.oracle.jdbc.Driver
Goodbye!
at java.net.URLClassLoader$1.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Unknown Source)
at JDBC.main(JDBC.java:21)
And My Code is
import java.sql.*;
public class JDBC {
public static void main(String[] args) {
Connection conn = null;
Statement stmt = null;
Open a connection
try{
Class.forName("com.oracle.jdbc.Driver");
System.out.println("Connecting to database...");
conn = DriverManager.getConnection
("jdbc:oracle:thin:#172.16.209.169:1521:heritage", "USERNAME", "PASSWORD");
}catch(SQLException se){
se.printStackTrace();
}catch(Exception e){
Handle errors for Class.forName
e.printStackTrace();
}finally{
try{
if(conn!=null)
conn.close();
}catch(SQLException se){
se.printStackTrace();
}
}
System.out.println("Goodbye!");
}

You need to add JDBC driver to your class path.
java.lang.ClassNotFoundException: com.oracle.jdbc.Driver // this error shows that your application is missing oracle jdbc driver.
Download Oracle jdbc driver, then add it to your class path.

Your ojdbc$version.jar seems not to be in the classpath.

How to connect ORACLE DB [duplicate]

This question already has answers here:
connect to sql server using jdbc
(2 answers)
Closed 9 years ago.
Here I'm trying to connect oracle which is installed in local machine with DSN bam.
I'm getting java.lang.ClassNotFoundException: oracle.jdbc.driver.OracleDriver Exception. Anybody please help me to fix this issue.
public class JdbcConnectionExample {
public static void main(String[] args) {
// TODO Auto-generated method stub
try {
Class.forName("oracle.jdbc.driver.OracleDriver");
Connection con = DriverManager
.getConnection("jdbc:oracle:thin:#localhost:1521:bam"
,"system","tiger");
Statement stmt = con.createStatement();
System.out.println("Created DB Connection....");
ResultSet rs = stmt.executeQuery("select * from tt");
while(rs.next()){
System.out.println(rs.getString("ename"));
System.out.println(rs.getInt("age"));
}
rs.close();
con.close();
} catch (ClassNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
}
The Log is here
java.lang.ClassNotFoundException: oracle.jdbc.driver.OracleDriver
at java.net.URLClassLoader$1.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Unknown Source)
at com.bam.sqlex.JdbcConnectionExample.main(JdbcConnectionExample.java:14)

May be u have not added jar of oracle driver download jar from here

java.lang.ClassNotFoundException: oracle.jdbc.driver.OracleDriver
Undoubtedly, you are lack of Oralce jar, improt it into your project

Class.forName("oracle.jdbc.driver.OracleDriver");
You have to check if this class is added to the classpath.

java.lang.ClassNotFoundException: com.mysql.jdbc.Driver - Not Working [duplicate]

This question already has answers here:
runtime error: java.lang.ClassNotFoundException: com.mysql.jdbc.Driver
(6 answers)
Closed 9 years ago.
I'm trying to run this program
import java.sql.*;
import java.io.*;
public class FirstExample
{
// JDBC driver name and database URL
static final String JDBC_DRIVER = "com.mysql.jdbc.Driver";
static final String DB_URL = "jdbc:mysql://localhost/EMP";
// Database credentials
static final String USER = "root";
static final String PASS = "pass";
public static void main(String[] args)
{
Connection conn = null;
Statement stmt = null;
try
{
//STEP 2: Register JDBC driver
Class.forName("com.mysql.jdbc.Driver");
//STEP 3: Open a connection
System.out.println("Connecting to database...");
conn = DriverManager.getConnection(DB_URL,USER,PASS);
//STEP 4: Execute a query
System.out.println("Creating statement...");
stmt = conn.createStatement();
String sql;
sql = "SELECT title,duration,protocol,URL,thumbURL,favorite FROM Videos";
ResultSet rs = stmt.executeQuery(sql);
//STEP 5: Extract data from result set
while(rs.next())
{
//Retrieve by column name
String title = rs.getString("title");
String duration = rs.getString("duration");
String protocol = rs.getString("protocol");
String URL = rs.getString("URL");
String thumbURL = rs.getString("thumbURL");
String favorite = rs.getString("favorite");
//Display
System.out.println("Title:" + title);
System.out.println("Duration:" + duration);
System.out.println("Protocol:" + protocol);
System.out.println("URL:" + URL);
System.out.println("ThumbURL:" + thumbURL);
System.out.println("Favorite:" + favorite);
}
//STEP 6: Clean-up environment
rs.close();
stmt.close();
conn.close();
}
catch(SQLException se)
{
//Handle errors for JDBC
se.printStackTrace();
}
catch(Exception e)
{
//Handle errors for Class.forName
e.printStackTrace();
}
finally
{
//finally block used to close resources
try
{
if(stmt!=null)
stmt.close();
}
catch(SQLException se2)
{
}// nothing we can do
try
{
if(conn!=null)
conn.close();
}
catch(SQLException se)
{
se.printStackTrace();
}//end finally try
}
System.out.println("Goodbye!");
}
}
But I'm getting the ClassNotFoundException
D:\XML Tests>javac FirstExample.java
D:\XML Tests>java FirstExample
java.lang.ClassNotFoundException: com.mysql.jdbc.Driver
at java.net.URLClassLoader$1.run(Unknown Source)
at java.net.URLClassLoader$1.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Unknown Source)
at FirstExample.main(FirstExample.java:21)
Goodbye!
Having consulted the numerous question available i.e setting the PATH system variable to the Connector directory, it still isnt working.
Any help please?

Add the jar containing the mysql driver class com.mysql.jdbc.Driver in the classpath.

Add MySQL driver jar to your project classpath and done.

The error is trying to tell you that it's not able to find the com.mysql.jdbc.Driver which is required when you are using MySql for data storage. So What you need to do is download the JConnector. And then import that jar file into your project classpath. Then you will not get the error.

java.lang.ClassNotFoundException: org.netezza.Driver

I am trying to connect to a Netezza database using the JDBC driver and do a simple SELECT query. I have the nzjdbc.jar file in the lib folder in my project (using eclipse) and I am getting the following error.
java.lang.ClassNotFoundException: org.netezza.Driver
at java.net.URLClassLoader$1.run(Unknown Source)
at java.net.URLClassLoader$1.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Unknown Source)
Here is my code:
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
public class Tests {
public static void main(String[] args)
{
String server = "myhost.com";
String port = "5480";
String dbName = "dbname";
String url = "jdbc:netezza://" + server + "/" + dbName ;
String user = "user";
String pwd = "pwd";
Connection conn = null;
Statement st = null;
ResultSet rs = null;
try {
Class.forName("org.netezza.Driver");
System.out.println(" Connecting ... ");
conn = DriverManager.getConnection(url, user, pwd);
System.out.println(" Connected "+conn);
String sql = "SELECT COUNT(*) FROM TABLE";
st = conn.createStatement();
rs = st.executeQuery(sql);
if(rs.next()) {
System.out.println(rs.getString(1));
} else {
System.out.println(" No data found");
}
} catch (Exception e) {
e.printStackTrace();
} finally {
try {
if( rs != null)
rs.close();
if( st!= null)
st.close();
if( conn != null)
conn.close();
} catch (SQLException e1) {
e1.printStackTrace();
}
}
}
}

In Eclipse you will need to add the jar to the libraries in your "Build path"
Eclipse documentation
Tutorial