--- /dev/null
+public class Inventory {
+ // Inventory flags
+ flag TransInitialize;
+
+ // Transaction variables
+ int numitems;
+ HashMap map;
+
+ // Constructor
+ public Inventory(){
+ map = new HashMap();
+ }
+
+ public Inventory(int howmany) {
+ numitems = howmany;// howmany keeps track of the number of items
+ // in the inventory
+ map = new HashMap();
+ }
+
+ // Add item to a list of inventory
+ public int additem(String name, int quantity, int price){
+ ItemInfo newitem = new ItemInfo(quantity, price);
+ // Get the item from hash
+ if (map.containsKey(name) == false) {
+ map.put(name, newitem);
+ } else {
+ ItemInfo i = (ItemInfo) map.get(name);
+ i.quantity += quantity;
+ i.price = price;
+ map.put(name, i);
+ }
+ return 0;
+ }
+
+ // Buy item from a given list of inventory
+ public int buyitem(String name, int quantity){
+ if (map.containsKey(name) == false) {
+ // System.printString("Error - Item does not exist");
+ return -1;
+ } else {
+ ItemInfo i = (ItemInfo) map.get(name);
+ if (i.quantity == 0) {
+ // System.printString("Error - Item unavailable");
+ return -1;
+ }
+ if ((i.quantity-quantity) < 0 ) {
+ // System.printString("Error - Available qty is less: Cannot Buy\n");
+ return -1;
+ } else {
+ i.quantity -= quantity;
+ map.put(name, i);
+ return i.price;
+ }
+ }
+ return 0;
+ }
+
+ //Display the inventory list
+ public String inventory(){
+ HashMapIterator i = new HashMapIterator(map, 0);// Gets key from the hashmap= name of item
+ HashMapIterator j = new HashMapIterator(map, 1);//Gets the value from hashmap
+ StringBuffer sb = new StringBuffer("");
+ while (i.hasNext() == true) {
+ Object o = i.next();
+ String name = o.toString();
+ ItemInfo oo = (ItemInfo) j.next();
+ sb.append(name);
+ sb.append(" ");
+ Integer q = new Integer(oo.quantity);
+ sb.append(q.toString());
+ sb.append(" ");
+ Integer p = new Integer(oo.price);
+ sb.append(p.toString());
+ sb.append("\n");
+ }
+ String item = new String(sb);
+ return item;
+ }
+}
--- /dev/null
+class ItemInfo {
+ int quantity;
+ int price;
+ ItemInfo(int x, int y) {
+ quantity = x;
+ price = y;
+ }
+}
--- /dev/null
+public class Logger {
+ //Logger flag
+ flag Initialize;
+ FileOutputStream fos;
+
+
+ //Constructor
+ public Logger(){
+ fos=new FileOutputStream("./Tests/htmlfiles/request.log");//Open request.log file
+ }
+
+ //Logs filename as per client requests
+ public void logrequest(String filename){
+ String request = new String("\nNew Request received: ");
+ fos.write(request.getBytes());
+ fos.write(filename.getBytes());
+ fos.flush();
+ }
+
+ public void logrequest(){
+ String request = new String("\nNew Request received: ");
+ fos.write(request.getBytes());
+ fos.flush();
+ }
+
+ public void closerequest() {
+ fos.close();
+ }
+}
--- /dev/null
+/* Startup object is generated with the initialstate flag set by the
+ * system to start the computation up */
+
+// Create New ServerSocket
+task Startup(StartupObject s {initialstate}) {
+// System.printString("W> Starting\n");
+ ServerSocket ss = new ServerSocket(9000);
+// System.printString("W> Creating ServerSocket\n");
+ Logger log = new Logger() {Initialize};
+ Inventory inventorylist = new Inventory(){TransInitialize};
+ taskexit(s {!initialstate}); /* Turns initial state flag off, so this task won't refire */
+}
+
+//Listen for a request and accept request
+task AcceptConnection(ServerSocket ss{SocketPending}) {
+// System.printString("W> Waiting for connection...\n");
+ WebServerSocket web = new WebServerSocket() {!WritePending, !TransPending, WebInitialize};
+ ss.accept(web);
+// System.printString("W> Connected... \n");
+}
+
+// Process the incoming http request
+task ProcessRequest(WebServerSocket web{IOPending && WebInitialize}) {
+//task ProcessRequest(WebServerSocket web{IOPending}) {
+ //System.printString("W> Inside ProcessRequest... \n");
+ if (web.clientrequest()) {
+ if(web.checktrans()==false)
+ // Not special transaction , do normal filesending
+ taskexit(web {WritePending, LogPending,!WebInitialize}); //Sets the WritePending and LogPending flag true
+ else
+ // Invoke special inventory transaction
+ taskexit(web {TransPending, LogPending,!WebInitialize});
+ }
+}
+
+//Do the WriteIO on server socket and send the requested file to Client
+task SendFile(WebServerSocket web{WritePending}) {
+// System.printString("W> Inside SendFile ... \n");
+ web.sendfile();
+ web.close();
+ taskexit(web {!WritePending});
+}
+
+// Log the Client request
+task LogRequest(WebServerSocket web{LogPending}, Logger log{Initialize}) {
+//Task fired when both
+// LogPending and Initialize flags are true
+// System.printString("L > Inside logrequest\n");
+ log.logrequest(web.filename);
+ taskexit(web {!LogPending});
+}
+
+//Transaction on Inventory
+task Transaction(WebServerSocket web{TransPending}, Inventory inventorylist{TransInitialize}){ //Task for WebServerTransactions
+// System.printString("T > Inside Transaction\n");
+ // Parse
+ int op = web.parseTransaction();
+ // Check for the kind of operation
+ if (op == 0 ) { /* Add */
+// System.printString("DEBUG > Calling add transaction\n");
+ Integer qty = new Integer(web.parsed[2]);
+ Integer price = new Integer(web.parsed[3]);
+ int ret = inventorylist.additem(web.parsed[1], qty.intValue(), price.intValue());
+ if (ret == 0) {
+ web.httpresponse();
+ StringBuffer s = new StringBuffer("Added Item ");
+ s.append(web.parsed[1]);
+ s.append(" Quantity ");
+ s.append(web.parsed[2]);
+ s.append(" Price ");
+ s.append(web.parsed[3]);
+ s.append("\n");
+ String towrite = new String(s);
+ web.write(towrite.getBytes());
+ } else {
+ web.httpresponse();
+ String s = new String("Error encountered");
+ web.write(s.getBytes());
+ }
+ } else if (op == 1) { /* Buy */
+// System.printString("DEBUG > Calling buy transaction\n");
+ Integer qty = new Integer(web.parsed[2]);
+ int ret = inventorylist.buyitem(web.parsed[1], qty.intValue());
+ if (ret >= 0) {
+ web.httpresponse();
+ StringBuffer s = new StringBuffer("Bought item ");
+ s.append(web.parsed[1]);
+ s.append(" Quantity ");
+ s.append(web.parsed[2]);
+ s.append(" Cost ");
+ Integer cost = new Integer(ret*qty.intValue());
+ String c = cost.toString();
+ s.append(c);
+ String towrite = new String(s);
+ web.write(towrite.getBytes());
+ } else {
+ web.httpresponse();
+ String s = new String("Error encountered");
+ web.write(s.getBytes());
+ }
+ } else if (op == 2) { /* Inventory */
+// System.printString("DEBUG > Calling inventory transaction\n");
+ web.httpresponse();
+ String towrite = inventorylist.inventory();
+ web.write(towrite.getBytes());
+ } else { /* Error */
+// System.printString("T > Error - Unknown transaction\n");
+ }
+ //Invoke close operations
+ web.close();
+ taskexit(web {!TransPending});
+}
--- /dev/null
+public class WebServerSocket extends Socket {
+ // Websocket flag
+ flag LogPending;
+ flag WritePending;
+ flag TransPending;
+ flag WebInitialize;
+
+ //Filename requested by the client
+ String filename;
+ String[] parsed;
+ String prefix;
+
+ //Constructor
+ public WebServerSocket(){
+ parsed = new String[4];
+ }
+
+ //Send the http header for web browser display
+ public void httpresponse(){
+ StringBuffer header = new StringBuffer("HTTP/1.0 200 OK\n");
+ header.append("Content-type: text/html\n");
+ header.append("\n\n");
+ String temp_str = new String(header);
+ write(temp_str.getBytes());
+ return;
+
+ }
+
+ // Send the html file , read from file one byte at a time
+ public void sendfile() {
+ StringBuffer req_file = new StringBuffer("./Tests/htmlfiles/");
+ req_file.append(filename);
+ String filepath = new String(req_file);
+ FileInputStream def_file = new FileInputStream(filepath);
+ int status = def_file.getfd();//Checks if the file is present in
+ //current directory
+ httpresponse();
+ if (status == -1){
+ StringBuffer response = new StringBuffer("404: not found: ");//Send 404 error if
+ // file not found
+ response.append(filename);
+ String buffer = new String(response);
+ write(buffer.getBytes());
+ def_file.close();
+ return;
+ }
+ byte buf[] = new byte[16];
+ int ret;
+
+ while ((ret = def_file.read(buf)) > 0) {// Read from file and write
+ // one byte at a time into the socket
+ byte tosend[] = new byte[ret];
+ for (int i = 0; i < ret; i++) {
+ tosend[i] = buf[i];
+ }
+ write(tosend);
+ //String str = new String(tosend);
+ }
+ def_file.close();
+ }
+
+ //Read the client request and extract the filename from it
+ public boolean clientrequest(){
+ byte b1[] = new byte[1024];
+ int numbytes=read(b1);//Read client request from web server socket
+ String curr=(new String(b1)).subString(0, numbytes);
+ if (prefix!=null) {
+ StringBuffer sb=new StringBuffer(prefix);
+ sb.append(curr);
+ curr=sb.toString();
+ }
+ prefix=curr;
+ if(prefix.indexOf("\r\n\r\n")>=0) {
+
+ int index = prefix.indexOf('/');//Parse the GET client request to find filename
+ int end = prefix.indexOf('H');
+ filename = prefix.subString((index+1), (end-1));
+ System.printString("\n");
+ return true;
+ }
+ return false;
+ }
+
+ // Parse for the prefix in the client request
+ // This is helpful to find if the prefix is a special transaction
+ public boolean checktrans(){
+ if (filename.startsWith("trans") == true) {
+ return true;
+ } else {
+ return false;
+ }
+ }
+
+ //Parse for the substrings in the filename and use it to obtain the
+ //kind of operation, name of item, quantity of item, price of item
+ //e.g. trans_add_car_2_10000 is the filename
+ //store in the parsed[] string , add,car,2,1000
+ public int parseTransaction(){
+ int start = filename.indexOf('_');
+ String s = filename.subString(start+1);
+
+ if (s.startsWith("add")==true){
+ // System.printString("DEBUG > ADD\n");
+ int i1 = s.indexOf('_');
+ parsed[0] = new String(s.subString(0,i1));
+
+ String s1 = s.subString(i1+1);
+ int i2 = s1.indexOf('_');
+ parsed[1] = new String(s1.subString(0,i2));
+
+ String s2 = s1.subString(i2+1);
+ int i3 = s2.indexOf('_');
+ parsed[2] = new String(s2.subString(0,i3));
+
+ String s3 = s2.subString(i3+1);
+ parsed[3] = s3;
+
+ return 0;
+
+ }
+ if (s.startsWith("buy")==true){
+ // System.printString("DEBUG > BUY\n");
+ int i1 = s.indexOf('_');
+ parsed[0] = s.subString(0,i1);
+
+ String s1 = s.subString(i1+1);
+ int i2 = s1.indexOf('_');
+ parsed[1] = s1.subString(0,i2);
+
+ String s2 = s1.subString(i2+1);
+ parsed[2] = s2;
+
+ parsed[3] = "";
+
+ return 1;
+ }
+ if (s.startsWith("inventory")==true){
+ // System.printString("DEBUG > INVENTORY\n");
+ return 2;
+
+ }
+ // Error transaction
+ return -1;
+ }
+}