Initial Commit

src/main/java/icu/samnyan/aqua/sega/util/ByteBufUtil.java

@@ -0,0 +1,59 @@
+package icu.samnyan.aqua.sega.util;
+
+import io.netty.buffer.ByteBuf;
+
+/**
+ * @author samnyan (privateamusement@protonmail.com)
+ */
+public class ByteBufUtil {
+
+    private static final char[] HEX_ARRAY = "0123456789ABCDEF".toCharArray();
+
+    /**
+     * Read bytes from start to current writer index
+     * Not modifying the reader index
+     *
+     * @param byteBuf The input buffer
+     * @return bytes
+     */
+    public static byte[] toBytes(ByteBuf byteBuf) {
+
+        int readerPos = byteBuf.readerIndex();
+        byteBuf.resetReaderIndex();
+        byte[] result = new byte[byteBuf.readableBytes()];
+        byteBuf.readBytes(result);
+
+        byteBuf.readerIndex(readerPos);
+        return result;
+    }
+
+    /**
+     * Move writer index to the capacity and read all the byte to the end
+     * Not modifying the reader index
+     *
+     * @param byteBuf The input buffer
+     * @return bytes
+     */
+    public static byte[] toAllBytes(ByteBuf byteBuf) {
+
+        int readerPos = byteBuf.readerIndex();
+        byteBuf.resetReaderIndex();
+        byteBuf.writerIndex(byteBuf.capacity());
+        byte[] result = new byte[byteBuf.capacity()];
+        byteBuf.readBytes(result);
+
+        byteBuf.readerIndex(readerPos);
+        return result;
+    }
+
+    public static String bytesToHex(byte[] bytes) {
+        char[] hexChars = new char[bytes.length * 2];
+        for (int j = 0; j < bytes.length; j++) {
+            int v = bytes[j] & 0xFF;
+            hexChars[j * 2] = HEX_ARRAY[v >>> 4];
+            hexChars[j * 2 + 1] = HEX_ARRAY[v & 0x0F];
+        }
+        return new String(hexChars);
+    }
+
+}