Initial commit

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

@@ -0,0 +1,116 @@
+package com.github.nkzawa.engineio.parser;
+
+
+import java.util.HashMap;
+import java.util.Map;
+
+public class Parser {
+
+    public static final int protocol = 2;
+    public static final Map<String, Integer> packets = new HashMap<String, Integer>() {{
+        put("open", 0);
+        put("close", 1);
+        put("ping", 2);
+        put("pong", 3);
+        put("message", 4);
+        put("upgrade", 5);
+        put("noop", 6);
+    }};
+    public static final Map<Integer, String> bipackets = new HashMap<Integer, String>();
+    static {
+        for (Map.Entry<String, Integer> entry : packets.entrySet()) {
+            bipackets.put(entry.getValue(), entry.getKey());
+        }
+    }
+
+    private static Packet err = new Packet("error", "parser error");
+
+
+    private Parser() {}
+
+    public static String encodePacket(Packet packet) {
+        String encoded = String.valueOf(packets.get(packet.type));
+
+        if (packet.data != null) {
+            encoded += packet.data;
+        }
+        return encoded;
+    }
+
+    public static Packet decodePacket(String data) {
+        int type = Character.getNumericValue(data.charAt(0));
+        if (type < 0 || type >= packets.size()) {
+            return err;
+        }
+
+        return new Packet(bipackets.get(type), data.length() > 1 ? data.substring(1) : null);
+    }
+
+    public static String encodePayload(Packet[] packets) {
+        if (packets.length == 0) {
+            return "0:";
+        }
+
+        StringBuilder encoded = new StringBuilder();
+        for (Packet packet : packets) {
+            String message = encodePacket(packet);
+            encoded.append(message.length()).append(":").append(message);
+        }
+
+        return encoded.toString();
+    }
+
+    public static void decodePayload(String data, DecodePayloadCallback callback) {
+        if (data == null || data.isEmpty()) {
+            callback.call(err, 0, 1);
+            return;
+        }
+
+        StringBuilder length = new StringBuilder();
+        for (int i = 0, l = data.length(); i < l; i++) {
+            char chr = data.charAt(i);
+
+            if (':' != chr) {
+                length.append(chr);
+            } else {
+                int n;
+                try {
+                    n = Integer.parseInt(length.toString());
+                } catch (NumberFormatException e) {
+                    callback.call(err, 0, 1);
+                    return;
+                }
+
+                String msg;
+                try {
+                    msg = data.substring(i + 1, i + 1 + n);
+                } catch (IndexOutOfBoundsException e) {
+                    callback.call(err, 0, 1);
+                    return;
+                }
+
+                if (msg.length() != 0) {
+                    Packet packet = decodePacket(msg);
+                    if (err.type.equals(packet.type) && err.data.equals(packet.data)) {
+                        callback.call(err, 0, 1);
+                        return;
+                    }
+
+                    boolean ret = callback.call(packet, i + n, l);
+                    if (!ret) return;
+                }
+
+                i += n;
+                length = new StringBuilder();
+            }
+        }
+
+        if (length.length() > 0) {
+            callback.call(err, 0, 1);
+        }
+    }
+
+    public static interface DecodePayloadCallback {
+        public boolean call(Packet packet, int index, int total);
+    }
+}