Java rmi

public int soma(int num1, int num2) throws RemoteException;

}

/////

package exercicioUam;

private static final long serialVersionUID = 1L;

protected SomadorRemoto() throws RemoteException{
	super(); 
}

@Override
public int soma(int num1, int num2) throws RemoteException {
	return num1 + num2;
}

public static void main(String[] args) {
    try {
        Somador somador = new SomadorRemoto();
        java.rmi.Naming.rebind("rmi://localhost:8000/SomadorService", somador);
        System.out.println("Servidor RMI pronto.");
    } catch (Exception e) {
        e.printStackTrace();
    }
}

}

Aparece mensagem de erro no console

java.rmi.ConnectException: Connection refused to host: localhost; nested exception is:

java.net.ConnectException: Connection refused: connect

at java.rmi/sun.rmi.transport.tcp.TCPEndpoint.newSocket(TCPEndpoint.java:625)

at java.rmi/sun.rmi.transport.tcp.TCPChannel.createConnection(TCPChannel.java:217)

at java.rmi/sun.rmi.transport.tcp.TCPChannel.newConnection(TCPChannel.java:204)

at java.rmi/sun.rmi.server.UnicastRef.newCall(UnicastRef.java:345)

at java.rmi/sun.rmi.registry.RegistryImpl_Stub.rebind(RegistryImpl_Stub.java:150)

at java.rmi/java.rmi.Naming.rebind(Naming.java:177)

at exercicioUam.SomadorRemoto.main(SomadorRemoto.java:22)

Caused by: java.net.ConnectException: Connection refused: connect

at java.base/sun.nio.ch.Net.connect0(Native Method)

at java.base/sun.nio.ch.Net.connect(Net.java:589)

at java.base/sun.nio.ch.Net.connect(Net.java:578)

at java.base/sun.nio.ch.NioSocketImpl.connect(NioSocketImpl.java:583)

at java.base/java.net.SocksSocketImpl.connect(SocksSocketImpl.java:327)

at java.base/java.net.Socket.connect(Socket.java:751)

at java.base/java.net.Socket.connect(Socket.java:686)

at java.base/java.net.Socket.(Socket.java:555)

at java.base/java.net.Socket.(Socket.java:324)

at java.rmi/sun.rmi.transport.tcp.TCPDirectSocketFactory.createSocket(TCPDirectSocketFactory.java:40)

at java.rmi/sun.rmi.transport.tcp.TCPEndpoint.newSocket(TCPEndpoint.java:619)

… 6 more