Optimization for Hex (#2476)

* Optimization for Hex

* fix checkstyle

HMCLCore/src/test/java/org/jackhuang/hmcl/util/HexTest.java

@@ -0,0 +1,51 @@
+/*
+ * Hello Minecraft! Launcher
+ * Copyright (C) 2023 huangyuhui <huanghongxun2008@126.com> and contributors
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+package org.jackhuang.hmcl.util;
+
+import org.junit.jupiter.api.Test;
+
+import java.io.IOException;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+public class HexTest {
+
+    @Test
+    public void testDecodeHex() throws IOException {
+        assertArrayEquals(new byte[0], Hex.decodeHex(""));
+        assertArrayEquals(new byte[1], Hex.decodeHex("00"));
+        assertArrayEquals(new byte[4], Hex.decodeHex("00000000"));
+
+        assertArrayEquals(
+                new byte[]{0x10, (byte) 0xa3, (byte) 0xd1, (byte) 0xff},
+                Hex.decodeHex("10a3D1Ff")
+        );
+
+        assertThrows(IOException.class, () -> Hex.decodeHex("1"));
+        assertThrows(IOException.class, () -> Hex.decodeHex("1a1"));
+        assertThrows(IOException.class, () -> Hex.decodeHex("1g"));
+    }
+
+    @Test
+    public void testEncodeHex() {
+        assertEquals("", Hex.encodeHex(new byte[0]));
+        assertEquals("00", Hex.encodeHex(new byte[1]));
+        assertEquals("00000000", Hex.encodeHex(new byte[4]));
+        assertEquals("10a3d1ff", Hex.encodeHex(new byte[]{0x10, (byte) 0xa3, (byte) 0xd1, (byte) 0xff}));
+    }
+}