NoClassDefFoundError

public class Teste {

	private Dbcp p = new Dbcp();

	public static void main(String[ ] args) {
		Teste t = new Teste();
		
		System.out.println(t.p);		
	}

}

import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStream;
import java.sql.Connection;
import java.sql.SQLException;
import java.util.Properties;

import javax.sql.DataSource;
import org.apache.commons.dbcp.BasicDataSource;

public class Dbcp { 
private static Dbcp instance = null; 
private DataSource ds; 
private Connection con; 
private String driver; 
private String url; 
private String login; 
private String password; 
private int maxConnections; 
private long maxWait; 

public Dbcp() { 
   Properties props = new Properties(); 
   try { 
      InputStream fis = this.getClass().getClassLoader().getResourceAsStream("db.properties"); 
      props.load(fis); 
      fis.close(); 
   } 
   catch(FileNotFoundException f) { 
      System.out.println("File not found in Dbcp --> constructor." + f.getMessage()); 
      f.printStackTrace(); 
   } 
   catch(IOException ioex){ 
      System.out.println("Error I/O in Dbpc --> constructor." + ioex.getMessage()); 
      ioex.printStackTrace(); 
   } 
   catch(Exception e) { 
      System.out.println("Error in Dbpc --> constructor." + e.getMessage()); 
      e.printStackTrace(); 
   } 

   driver = props.getProperty("driver"); 
   url = props.getProperty("url"); 
   login = props.getProperty("login"); 
   password = props.getProperty("password"); 
   maxConnections = (new Integer(props.getProperty("maxConnections"))).intValue(); 
   maxWait = (new Long(props.getProperty("maxWait"))).longValue(); 
   ds = setupDataSource(); 
} 

public static Dbcp getInstance() { 
   if(instance == null) { 
      instance = new Dbcp(); 
   } 
   return instance; 
} 

public Connection getConn() throws SQLException { 
   return ds.getConnection(); 
} 

private DataSource setupDataSource() { 
   BasicDataSource ds = new BasicDataSource(); 
   ds.setDriverClassName(driver); 
   ds.setUsername(login); 

   ds.setPassword(password); 
   ds.setUrl(url); 
   ds.setMaxActive(maxConnections); 
   ds.setMaxWait(maxWait); 
   ds.setDefaultAutoCommit(false); 
   return ds; 
} 

public void printDataSourceStats() throws SQLException { 
   BasicDataSource bds = (BasicDataSource) ds; 
   System.out.println("NumActive: " + bds.getNumActive()); 
   System.out.println("NumIdle: " + bds.getNumIdle()); 
} 

public void shutdown() throws SQLException { 
   BasicDataSource bds = (BasicDataSource) ds; 
   bds.close(); 
   } 
}