Initial commit

src/main/java/com/github/nkzawa/socketio/parser/Parser.java

@@ -0,0 +1,131 @@
+package com.github.nkzawa.socketio.parser;
+
+import com.google.gson.Gson;
+import com.google.gson.JsonParseException;
+import com.google.gson.JsonParser;
+import com.google.gson.JsonPrimitive;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.logging.Logger;
+
+public class Parser {
+
+    private static final Logger logger = Logger.getLogger("socket.io-parser");
+
+    private static final Gson gson = new Gson();
+    private static final JsonParser parser = new JsonParser();
+
+    public static final int CONNECT = 0;
+    public static final int DISCONNECT = 1;
+    public static final int EVENT = 2;
+    public static final int ACK = 3;
+    public static final int ERROR = 4;
+
+    public static int protocol = 1;
+    public static List<String > types = new ArrayList<String>() {{
+        add("CONNECT");
+        add("DISCONNECT");
+        add("EVENT");
+        add("ACK");
+        add("ERROR");
+    }};
+
+    private Parser() {}
+
+    public static String encode(Packet obj) {
+        StringBuilder str = new StringBuilder();
+        boolean nsp = false;
+        str.append(obj.type);
+
+        if (obj.nsp != null && !obj.nsp.isEmpty() && !"/".equals(obj.nsp)) {
+            nsp = true;
+            str.append(obj.nsp);
+        }
+
+        if (obj.id >= 0) {
+            if (nsp) {
+                str.append(",");
+                nsp = false;
+            }
+            str.append(obj.id);
+        }
+
+        if (obj.data != null) {
+            if (nsp) str.append(",");
+            str.append(gson.toJson(obj.data));
+        }
+
+        logger.info(String.format("encoded %s as %s", obj, str));
+        return str.toString();
+    }
+
+    public static Packet decode(String str) {
+        Packet p = new Packet();
+        int i = 0;
+
+        try {
+            p.type = Character.getNumericValue(str.charAt(0));
+            types.get(p.type);
+        } catch (IndexOutOfBoundsException e) {
+            return error();
+        }
+
+        char next = Character.UNASSIGNED;
+        try {
+            next = str.charAt(i + 1);
+        } catch (IndexOutOfBoundsException e) {
+            // do nothing
+        }
+        if (next == '/') {
+            StringBuilder nsp = new StringBuilder();
+            while (true) {
+                ++i;
+                char c = str.charAt(i);
+                if (c == ',') break;
+                nsp.append(c);
+                if (i + 1 == str.length()) break;
+            }
+            p.nsp = nsp.toString();
+        } else {
+            p.nsp = "/";
+        }
+
+        next = Character.UNASSIGNED;
+        try {
+            next = str.charAt(i + 1);
+        } catch (IndexOutOfBoundsException e) {
+            // do nothing
+        }
+        if (Character.getNumericValue(next) != -1) {
+            StringBuilder id = new StringBuilder();
+            while (true) {
+                ++i;
+                Character c = str.charAt(i);
+                if (c == null || Character.getNumericValue(c) == -1) {
+                    --i;
+                    break;
+                }
+                id.append(c);
+                if (i + 1 == str.length()) break;
+            }
+            p.id = Integer.parseInt(id.toString());
+        }
+
+        try {
+            str.charAt(++i);
+            p.data = parser.parse(str.substring(i));
+        } catch (IndexOutOfBoundsException e) {
+            // do nothing
+        } catch (JsonParseException e) {
+            return error();
+        }
+
+        logger.info(String.format("decoded %s as %s", str, p));
+        return p;
+    }
+
+    private static Packet error() {
+        return new Packet(ERROR, new JsonPrimitive("parser error"));
+    }
+}