From 97758682207518c375a67803001d332d6533f270 Mon Sep 17 00:00:00 2001
From: micuncang <micuncang@gmail.com>
Date: Wed, 16 Mar 2022 00:25:16 +0800
Subject: [PATCH] =?UTF-8?q?Base32=E6=B7=BB=E5=8A=A0"=3D"=E8=A1=A5=E7=A0=81?=
 =?UTF-8?q?=E6=9C=BA=E5=88=B6?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 .../java/cn/hutool/core/codec/Base32.java     | 21 +++++++++++++------
 .../java/cn/hutool/core/codec/Base32Test.java |  2 +-
 2 files changed, 16 insertions(+), 7 deletions(-)

diff --git a/hutool-core/src/main/java/cn/hutool/core/codec/Base32.java b/hutool-core/src/main/java/cn/hutool/core/codec/Base32.java
index 030bf6e66..f98619138 100644
--- a/hutool-core/src/main/java/cn/hutool/core/codec/Base32.java
+++ b/hutool-core/src/main/java/cn/hutool/core/codec/Base32.java
@@ -1,10 +1,10 @@
 package cn.hutool.core.codec;
 
-import java.nio.charset.Charset;
-
 import cn.hutool.core.util.CharsetUtil;
 import cn.hutool.core.util.StrUtil;
 
+import java.nio.charset.Charset;
+
 /**
  * Base32 - encodes and decodes RFC3548 Base32 (see http://www.faqs.org/rfcs/rfc3548.html )<br>
  * base32就是用32（2的5次方）个特定ASCII码来表示256个ASCII码。<br>
@@ -30,6 +30,7 @@ public class Base32 {
 			0x0F, 0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, // 'p', 'q', 'r', 's', 't', 'u', 'v', 'w'
 			0x17, 0x18, 0x19, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF // 'x', 'y', 'z', '{', '|', '}', '~', 'DEL'
 	};
+	private static final int[] BASE32_FILL = {-1, 4, 1, 6, 3};
 
 	//----------------------------------------------------------------------------------------- encode
 	/**
@@ -43,10 +44,17 @@ public class Base32 {
 		int digit;
 		int currByte;
 		int nextByte;
-		StringBuilder base32 = new StringBuilder((bytes.length + 7) * 8 / 5);
+
+		int encodeLen = bytes.length * 8 / 5;
+		if (encodeLen != 0) {
+			encodeLen = encodeLen + 1 + BASE32_FILL[(bytes.length * 8) % 5];
+		}
+
+		StringBuilder base32 = new StringBuilder(encodeLen);
 
 		while (i < bytes.length) {
-			currByte = (bytes[i] >= 0) ? bytes[i] : (bytes[i] + 256); // unsign
+			// unsign
+			currByte = (bytes[i] >= 0) ? bytes[i] : (bytes[i] + 256);
 
 			/* Is the current digit going to span a byte boundary? */
 			if (index > 3) {
@@ -71,7 +79,7 @@ public class Base32 {
 			base32.append(BASE32_CHARS.charAt(digit));
 		}
 
-		return base32.toString();
+		return StrUtil.fillAfter(base32.toString(), '=', encodeLen);
 	}
 
 	/**
@@ -114,7 +122,8 @@ public class Base32 {
 	 */
 	public static byte[] decode(final String base32) {
 		int i, index, lookup, offset, digit;
-		byte[] bytes = new byte[base32.length() * 5 / 8];
+		int len = base32.endsWith("=") ? base32.indexOf("=") * 5 / 8 : base32.length() * 5 / 8;
+		byte[] bytes = new byte[len];
 
 		for (i = 0, index = 0, offset = 0; i < base32.length(); i++) {
 			lookup = base32.charAt(i) - '0';
diff --git a/hutool-core/src/test/java/cn/hutool/core/codec/Base32Test.java b/hutool-core/src/test/java/cn/hutool/core/codec/Base32Test.java
index 76313f085..b19d98762 100644
--- a/hutool-core/src/test/java/cn/hutool/core/codec/Base32Test.java
+++ b/hutool-core/src/test/java/cn/hutool/core/codec/Base32Test.java
@@ -9,7 +9,7 @@ public class Base32Test {
 	public void encodeAndDecodeTest(){
 		String a = "伦家是一个非常长的字符串";
 		String encode = Base32.encode(a);
-		Assert.assertEquals("4S6KNZNOW3TJRL7EXCAOJOFK5GOZ5ZNYXDUZLP7HTKCOLLMX46WKNZFYWI", encode);
+		Assert.assertEquals("4S6KNZNOW3TJRL7EXCAOJOFK5GOZ5ZNYXDUZLP7HTKCOLLMX46WKNZFYWI======", encode);
 
 		String decodeStr = Base32.decodeStr(encode);
 		Assert.assertEquals(a, decodeStr);