Problemas com conexão e fazer um cadastro

The server encountered an internal error () that prevented it from fulfilling this request.
exception 

javax.servlet.ServletException: Wrapper cannot find servlet class ServletCadastrarCliente or a class it depends on
	org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:105)
	org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:148)
	org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:869)
	org.apache.coyote.http11.Http11BaseProtocol$Http11ConnectionHandler.processConnection(Http11BaseProtocol.java:664)
	org.apache.tomcat.util.net.PoolTcpEndpoint.processSocket(PoolTcpEndpoint.java:527)
	org.apache.tomcat.util.net.LeaderFollowerWorkerThread.runIt(LeaderFollowerWorkerThread.java:80)
	org.apache.tomcat.util.threads.ThreadPool$ControlRunnable.run(ThreadPool.java:684)
	java.lang.Thread.run(Thread.java:619)


root cause 

java.lang.ClassNotFoundException: ServletCadastrarCliente
	org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1352)
	org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1198)
	org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:105)
	org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:148)
	org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:869)
	org.apache.coyote.http11.Http11BaseProtocol$Http11ConnectionHandler.processConnection(Http11BaseProtocol.java:664)
	org.apache.tomcat.util.net.PoolTcpEndpoint.processSocket(PoolTcpEndpoint.java:527)
	org.apache.tomcat.util.net.LeaderFollowerWorkerThread.runIt(LeaderFollowerWorkerThread.java:80)
	org.apache.tomcat.util.threads.ThreadPool$ControlRunnable.run(ThreadPool.java:684)
	java.lang.Thread.run(Thread.java:619)

note The full stack trace of the root cause is available in the Apache Tomcat/5.5.17 logs.

public class Banco {
    
    private Connection con = null;
    private Statement st = null;
    private ResultSet rs = null;
    
        /** Creates a new instance of Banco */
    public Banco() throws Exception{
        Class.forName("org.postgresql.Driver");
        con = DriverManager.getConnection("jdbc:postgresql:Cliente","postgres","postgres");
        st = con.createStatement();  
    }
        
    public void salvar(Cliente cli) throws Exception{
      
        st.executeUpdate("insert into Cliente values ('"+cli.getNome()+"','"+cli.getEndereco()+"','"+cli.getBairro()+"','"+cli.getTelefone()+"','"+cli.getEmail()+")");

    }
    
    public Cliente consultar(String nome)throws Exception{
        Cliente cli=null;
        rs = st.executeQuery("select * from Cliente where  nome = '"+nome+"'");
        
        while(rs.next()){
            cli = new Cliente();
            cli.setNome(rs.getString(1));
            cli.setEndereco(rs.getString(2));
            cli.setBairro(rs.getString(3));
            cli.setTelefone(rs.getString(4));
            cli.setEmail(rs.getString(5));
                        
        }
        
        return cli;
    }
}