querylastmsgs.java

SMPP（点到点短消息协议）的java实现

package ie.omk.smpp.message;

import ie.omk.smpp.Address;
import ie.omk.smpp.util.GSMConstants;
import ie.omk.smpp.util.SMPPIO;

import java.io.OutputStream;

/**
 * Query the last number of messages sent from a certain ESME. Relevant
 * inherited fields from SMPPPacket: <br>
 * <ul>
 * source <br>
 * </ul>
 * 
 * @author Oran Kelly
 * @version 1.0
 */
public class QueryLastMsgs extends ie.omk.smpp.message.SMPPRequest {
    /** Number of messages to look up */
    private int msgCount;

    /**
     * Construct a new QueryLastMsgs.
     */
    public QueryLastMsgs() {
        super(QUERY_LAST_MSGS);
        msgCount = 0;
    }

    /**
     * Construct a new QueryLastMsgs with specified sequence number.
     * 
     * @param seqNum
     *            The sequence number to use
     * @deprecated
     */
    public QueryLastMsgs(int seqNum) {
        super(QUERY_LAST_MSGS, seqNum);
        msgCount = 0;
    }

    /**
     * Set the number of messages to look up. The minimum number of messages to
     * query is 1 and the maximum is 100.
     * 
     * @param n
     *            The message count (1 &lt;= n &lt;= 100)
     * @throws ie.omk.smpp.message.InvalidParameterValueException
     *             if the count is set outside the valid range.
     */
    public void setMsgCount(int n) throws InvalidParameterValueException {
        if (n > 0 && n <= 100) {
            this.msgCount = n;
        } else {
            throw new InvalidParameterValueException(
                    "Message count must be between 1 and 100", n);
        }
    }

    /** Get the number of messages being requested. */
    public int getMsgCount() {
        return msgCount;
    }

    public int getBodyLength() {
        int len = (source != null) ? source.getLength() : 3;

        // 1 1-byte integer
        return len + 1;
    }

    /**
     * Write a byte representation of this packet to an OutputStream
     * 
     * @param out
     *            The OutputStream to write to
     * @throws java.io.IOException
     *             if there's an error writing to the output stream.
     */
    protected void encodeBody(OutputStream out) throws java.io.IOException {
        if (source != null) {
            source.writeTo(out);
        } else {
            // Write ton=0(null), npi=0(null), address=\0(nul)
            new Address(GSMConstants.GSM_TON_UNKNOWN,
                    GSMConstants.GSM_NPI_UNKNOWN, "").writeTo(out);
        }
        SMPPIO.writeInt(msgCount, 1, out);
    }

    public void readBodyFrom(byte[] body, int offset)
            throws SMPPProtocolException {
        source = new Address();
        source.readFrom(body, offset);
        offset += source.getLength();

        msgCount = SMPPIO.bytesToInt(body, offset++, 1);
    }

    /**
     * Convert this packet to a String. Not to be interpreted programmatically,
     * it's just dead handy for debugging!
     */
    public String toString() {
        return new String("query_last_msgs");
    }
}