Incompatible Map Entry with ENUm in java

Why am i getting "The return type is incompatible with Map.Entry<SEND,CANDataSendInfo>.getKey()"

Here i am trying to make object which consist of enum as key and Class Object as Value but instead i am getting issue at line public SEND getKey()

package cantestbus;

import java.util.Map;

public class SendKV<SEND , CANDataSendInfo> implements Map.Entry<SEND , CANDataSendInfo>
{   
    enum SEND 
    { 
        SEND_0x41, SEND_0x42, SEND_0x43, SEND_0x44, SEND_0x61, SEND_0x62, SEND_0x63, SEND_0x64 
    }  

    private SEND key;
    private CANDataSendInfo value;

    public SendKV(SEND key, CANDataSendInfo value)
    {
        this.key = key;
        this.value = value;
    }

    public SEND setKey(SEND key)
    {
        return this.key = key;
    }

    public SEND getKey()
    {
        return this.key;
    }

    public CANDataSendInfo setValue(CANDataSendInfo value)
    {
        return this.value = value;
    }

    public CANDataSendInfo getValue()
    {
        return this.value;
    }

}