/*
*
*
* Copyright 1990-2007 Sun Microsystems, Inc. All Rights Reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License version
* 2 only, as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License version 2 for more details (a copy is
* included at /legal/license.txt).
*
* You should have received a copy of the GNU General Public License
* version 2 along with this work; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
* 02110-1301 USA
*
* Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa
* Clara, CA 95054 or visit www.sun.com if you need additional
* information or have any questions.
*/
package com.sun.midp.services;
import com.sun.midp.links.*;
import java.io.*;
final class SystemServiceRequestProtocolAMS {
final static int SERVICE_REQUEST_STATUS_OK = 0;
final static int SERVICE_REQUEST_STATUS_ERROR = 1;
private final static int INVALID_STATE = -1;
private final static int WAIT_FOR_BEGIN_SESSION_STATE = 1;
private final static int WAIT_FOR_SERVICE_ID_STATE = 2;
private final static int SEND_SERVICE_REQUEST_STATUS_STATE = 3;
private final static int SEND_SERVICE_TO_CLIENT_LINK_STATE = 4;
private final static int SEND_CLIENT_TO_SERVICE_LINK_STATE = 5;
private final static int WAIT_FOR_LINKS_RECEIVED_ACK_STATE = 6;
private final static int WAIT_FOR_END_SESSION_STATE = 7;
private final static int END_SESSION_STATE = 8;
private final static int END_STATE = 9;
private SystemServiceRequestListener requestListener;
private int state = INVALID_STATE;
SystemServiceRequestProtocolAMS(
SystemServiceRequestListener requestListener) {
/**
* Argument sanity check
*/
if (requestListener == null) {
throw new NullPointerException();
}
this.requestListener = requestListener;
}
SystemServiceConnectionLinks handleServiceRequest(
SystemServiceConnectionLinks sendReceiveLinks)
throws ClosedLinkException,
InterruptedIOException,
IOException {
Link sendLink = sendReceiveLinks.getSendLink();
Link receiveLink = sendReceiveLinks.getReceiveLink();
/**
* Arguments sanity checks
*/
if (sendLink == null || receiveLink == null) {
throw new NullPointerException();
}
if (!sendLink.isOpen() || !receiveLink.isOpen()) {
throw new IllegalStateException();
}
SystemServiceConnectionLinks connectionLinks = null;
state = WAIT_FOR_BEGIN_SESSION_STATE;
try {
connectionLinks = doHandleServiceRequest(sendLink, receiveLink);
} finally {
state = INVALID_STATE;
}
return connectionLinks;
}
private SystemServiceConnectionLinks doHandleServiceRequest(
Link sendLink, Link receiveLink)
throws ClosedLinkException,
InterruptedIOException,
IOException {
String serviceID = "";
SystemServiceConnectionLinks connectionLinks = null;
if (state == INVALID_STATE) {
throw new IllegalStateException();
}
while (state != END_STATE) {
switch (state) {
case WAIT_FOR_BEGIN_SESSION_STATE: {
// wait for session begin request
LinkMessage msg = receiveLink.receive();
String str = msg.extractString();
// check request validity
if (!str.equals(
SystemServiceRequestProtocolClient.START_SESSION_STR)) {
throw new IllegalStateException();
}
// advance to next state
state = WAIT_FOR_SERVICE_ID_STATE;
break;
}
case WAIT_FOR_SERVICE_ID_STATE: {
// wait for service id
LinkMessage msg = receiveLink.receive();
serviceID = msg.extractString();
// advance to next state
state = SEND_SERVICE_REQUEST_STATUS_STATE;
break;
}
case SEND_SERVICE_REQUEST_STATUS_STATE: {
// try to obtain connection to service
int status = SERVICE_REQUEST_STATUS_OK;
try {
connectionLinks = null;
connectionLinks =
requestListener.onServiceRequest(serviceID);
} finally {
if (connectionLinks == null) {
status = SERVICE_REQUEST_STATUS_ERROR;
}
// send status
ByteArrayOutputStream bos =
new ByteArrayOutputStream();
DataOutputStream os = new DataOutputStream(bos);
os.writeInt(status);
byte[] data = bos.toByteArray();
LinkMessage msg = LinkMessage.newDataMessage(data);
sendLink.send(msg);
// advance to next state
if (status == SERVICE_REQUEST_STATUS_OK) {
state = SEND_SERVICE_TO_CLIENT_LINK_STATE;
} else {
state = END_STATE;
}
}
break;
}
case SEND_SERVICE_TO_CLIENT_LINK_STATE: {
// send service to client link
Link link = connectionLinks.getSendLink();
LinkMessage msg = LinkMessage.newLinkMessage(link);
sendLink.send(msg);
// advance to next state
state = SEND_CLIENT_TO_SERVICE_LINK_STATE;
break;
}
case SEND_CLIENT_TO_SERVICE_LINK_STATE: {
// send client to service link
Link link = connectionLinks.getReceiveLink();
LinkMessage msg = LinkMessage.newLinkMessage(link);
sendLink.send(msg);
// advance to next state
state = WAIT_FOR_LINKS_RECEIVED_ACK_STATE;
break;
}
case WAIT_FOR_LINKS_RECEIVED_ACK_STATE: {
// wait for links recieved ack
LinkMessage msg = receiveLink.receive();
String str = msg.extractString();
// check request validity
if (!str.equals(SystemServiceRequestProtocolClient.
LINKS_RECEIVED_ACK_STR)) {
throw new IllegalStateException();
}
// notify listener about connection passed to client
if (connectionLinks != null) {
requestListener.onLinksPassedToClient(connectionLinks);
}
// advance to next state
state = WAIT_FOR_END_SESSION_STATE;
break;
}
case WAIT_FOR_END_SESSION_STATE: {
// wait for session end request
LinkMessage msg = receiveLink.receive();
String str = msg.extractString();
// check request validity
if (!str.equals(
SystemServiceRequestProtocolClient.END_SESSION_STR)) {
throw new IllegalStateException();
}
// advance to next state
state = END_SESSION_STATE;
break;
}
case END_SESSION_STATE: {
// advance to next state
state = END_STATE;
break;
}
}
}
state = INVALID_STATE;
return connectionLinks;
}
}
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