/* start a transaction and add to transaction table */ public Transaction start() { Transaction t = new Transaction(random.nextInt(Integer.MAX_VALUE)); t.addCommand("start", "start"); ArrayList<RMmeta.RMtype> types = new ArrayList<RMmeta.RMtype>(); transactionTable.put(t, types); types.add(null); List<RMmeta> rms = middleware.resourceManagers; synchronized (rms) { for (RMmeta rm : rms) { Socket s = rm.getSocket(); synchronized (s) { try { BufferedReader inFromServer = new BufferedReader(new InputStreamReader(s.getInputStream())); DataOutputStream outToServer = new DataOutputStream(s.getOutputStream()); outToServer.writeBytes("start," + t.getId() + '\n'); System.out.println(inFromServer.readLine()); } catch (Exception e) { e.printStackTrace(); } } } } return t; }
/* abort a transaction, return true if success, false if not */ public boolean abort(Transaction t) { if (!transactionTable.keySet().contains(t)) { System.out.println("Oops where does this transaction come from. " + t.toString()); return false; } System.out.println("ABORTING: " + t.toString()); List<RMmeta> rms = middleware.resourceManagers; synchronized (rms) { for (RMmeta rm : rms) { Socket s = rm.getSocket(); synchronized (s) { try { BufferedReader inFromServer = new BufferedReader(new InputStreamReader(s.getInputStream())); DataOutputStream outToServer = new DataOutputStream(s.getOutputStream()); outToServer.writeBytes("abort," + t.getId() + '\n'); System.out.println(inFromServer.readLine()); } catch (Exception e) { e.printStackTrace(); } } } } this.middleware.lockManager.UnlockAll(t.getId()); t.addCommand("abort", "abort"); transactionTable.remove(t); return true; }
/* commit a transaction, return true if success, false if not */ public boolean commit(Transaction t) { if (!transactionTable.keySet().contains(t)) { System.out.println("Oops where does this transaction come from. " + t.toString()); return false; } System.out.println("COMMIT: " + t.toString()); t.addCommand("commit", "commit"); List<RMmeta> rms = middleware.resourceManagers; synchronized (rms) { boolean result = true; // ask each rm to vote for (RMmeta rm : rms) { Socket s = rm.getSocket(); synchronized (s) { try { BufferedReader inFromServer = new BufferedReader(new InputStreamReader(s.getInputStream())); DataOutputStream outToServer = new DataOutputStream(s.getOutputStream()); outToServer.writeBytes("vote," + t.getId() + '\n'); // crash point if (middleware.crashType == MiddlewareCrashType .CRASH_AFTER_SENDING_VOTE_REQUEST_AND_BEFORE_RECEIVING_ANY_REPLIES) { System.out.println(middleware.crashType.toString()); System.exit(1); } String ret = inFromServer.readLine(); // if any return null(crash) or no then result is false if (ret == null || ret.compareToIgnoreCase("no") == 0) result = false; } catch (Exception e) { e.printStackTrace(); } } } // crash point if (middleware.crashType == MiddlewareCrashType.CRASH_AFTER_RECEIVING_ALL_REPLIES_BUT_BEFORE_DECIDING) { System.out.println(middleware.crashType.toString()); System.exit(1); } // if all vote yes, then commit if (result) { System.out.println("Decide to commit:" + t.toString()); // crash point if (middleware.crashType == MiddlewareCrashType.CRASH_AFTER_DECIDING_BUT_BEFORE_SENDING_DECISION) { System.out.println(middleware.crashType.toString()); System.exit(1); } for (RMmeta rm : rms) { Socket s = rm.getSocket(); synchronized (s) { try { BufferedReader inFromServer = new BufferedReader(new InputStreamReader(s.getInputStream())); DataOutputStream outToServer = new DataOutputStream(s.getOutputStream()); outToServer.writeBytes("commit," + t.getId() + '\n'); System.out.println(inFromServer.readLine()); // crash point if (middleware.crashType == MiddlewareCrashType.CRASH_AFTER_SENDING_SOME_BUT_NOT_ALL_DECISIONS) { System.out.println(middleware.crashType.toString()); System.exit(1); } } catch (Exception e) { e.printStackTrace(); } } } t.addCommand("commit", "commit"); // if any vote no, then abort } else { System.out.println("Decide to abort: " + t.toString()); // crash point if (middleware.crashType == MiddlewareCrashType.CRASH_AFTER_DECIDING_BUT_BEFORE_SENDING_DECISION) { System.out.println(middleware.crashType.toString()); System.exit(1); } for (RMmeta rm : rms) { Socket s = rm.getSocket(); synchronized (s) { try { BufferedReader inFromServer = new BufferedReader(new InputStreamReader(s.getInputStream())); DataOutputStream outToServer = new DataOutputStream(s.getOutputStream()); outToServer.writeBytes("abort," + t.getId() + '\n'); System.out.println(inFromServer.readLine()); // crash point if (middleware.crashType == MiddlewareCrashType.CRASH_AFTER_SENDING_SOME_BUT_NOT_ALL_DECISIONS) { System.out.println(middleware.crashType.toString()); System.exit(1); } } catch (Exception e) { e.printStackTrace(); } } } t.addCommand("abort", "abort"); } // crash point if (middleware.crashType == MiddlewareCrashType.CRASH_AFTER_HAVING_SENT_ALL_DECISIONS) { System.out.println(middleware.crashType.toString()); System.exit(1); } } this.middleware.lockManager.UnlockAll(t.getId()); transactionTable.remove(t); return true; }