帮我写一个java对接smpp

Sure, I can help you with that. Here's a basic example of how to connect to an SMPP server using Java:

import java.io.IOException;
import java.util.concurrent.TimeoutException;

import org.jsmpp.InvalidResponseException;
import org.jsmpp.PDUException;
import org.jsmpp.bean.BindType;
import org.jsmpp.bean.DataCoding;
import org.jsmpp.bean.ESMClass;
import org.jsmpp.bean.NumberingPlanIndicator;
import org.jsmpp.bean.TypeOfNumber;
import org.jsmpp.session.BindParameter;
import org.jsmpp.session.SMPPSession;
import org.jsmpp.util.AbsoluteTimeFormatter;
import org.jsmpp.util.TimeFormatter;

public class SMPPClient {

    private static final TimeFormatter TIME_FORMATTER = new AbsoluteTimeFormatter();

    public static void main(String[] args) throws IOException, InvalidResponseException, PDUException, TimeoutException {
        String host = "localhost";
        int port = 2775;
        String systemId = "mySystemId";
        String password = "myPassword";
        String systemType = "mySystemType";
        TypeOfNumber sourceAddrTon = TypeOfNumber.ALPHANUMERIC;
        NumberingPlanIndicator sourceAddrNpi = NumberingPlanIndicator.UNKNOWN;
        String sourceAddr = "mySourceAddr";
        TypeOfNumber destAddrTon = TypeOfNumber.INTERNATIONAL;
        NumberingPlanIndicator destAddrNpi = NumberingPlanIndicator.ISDN;
        String destAddr = "1234567890";
        String shortMessage = "Hello, world!";
        ESMClass esmClass = new ESMClass();
        esmClass.setGsmFeatures(0);
        esmClass.setMwi(0);
        esmClass.setReplyPath(0);
        DataCoding dataCoding = new DataCoding(0);
        SMPPSession session = new SMPPSession();
        session.connectAndBind(host, port, new BindParameter(BindType.BIND_TX, systemId, password, systemType, sourceAddrTon, sourceAddrNpi, sourceAddr, null));
        session.submitShortMessage("CMT", sourceAddrTon, sourceAddrNpi, sourceAddr, destAddrTon, destAddrNpi, destAddr, esmClass, (byte)0, (byte)1, TIME_FORMATTER.format(System.currentTimeMillis()), null, dataCoding, (byte)0, shortMessage.getBytes());
        session.unbindAndClose();
    }

}

This code uses the jSMPP library to connect to an SMPP server and send a short message. You'll need to replace the values for `host`, `port`, `systemId`, `password`, `systemType`, `sourceAddr`, and `destAddr` with the appropriate values for your SMPP server and account.