feat: 新增 base32 编码工具类

sa-token-core/src/main/java/cn/dev33/satoken/secure/SaBase32Util.java

@@ -0,0 +1,126 @@
+/*
+ * Copyright 2020-2099 sa-token.cc
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package cn.dev33.satoken.secure;
+
+import java.nio.charset.StandardCharsets;
+
+/**
+ * Sa-Token Base32 工具类
+ *
+ * @author click33
+ * @since 1.41.0
+ */
+public class SaBase32Util {
+
+    private static final String BASE32_CHARS = "ABCDEFGHIJKLMNOPQRSTUVWXYZ234567";
+    private static final int[] BASE32_LOOKUP = new int[256];
+
+    static {
+        // 初始化解码查找表
+        for (int i = 0; i < BASE32_CHARS.length(); i++) {
+            char c = BASE32_CHARS.charAt(i);
+            BASE32_LOOKUP[c] = i;
+            // 支持小写字母解码
+            if (c >= 'A' && c <= 'Z') {
+                BASE32_LOOKUP[Character.toLowerCase(c)] = i;
+            }
+        }
+    }
+
+    /**
+     * Base32 编码（byte[] 转 String）
+     */
+    public static String encodeBytesToString(byte[] bytes) {
+        if (bytes == null) return null;
+
+        StringBuilder result = new StringBuilder();
+        int buffer = 0;
+        int bufferSize = 0;
+
+        for (byte b : bytes) {
+            buffer = (buffer << 8) | (b & 0xFF);
+            bufferSize += 8;
+
+            while (bufferSize >= 5) {
+                bufferSize -= 5;
+                int index = (buffer >> bufferSize) & 0x1F;
+                result.append(BASE32_CHARS.charAt(index));
+            }
+        }
+
+        // 处理剩余位
+        if (bufferSize > 0) {
+            int index = (buffer << (5 - bufferSize)) & 0x1F;
+            result.append(BASE32_CHARS.charAt(index));
+        }
+
+        return result.toString();
+    }
+
+    /**
+     * Base32 解码（String 转 byte[]）
+     */
+    public static byte[] decodeStringToBytes(String text) {
+        if (text == null) return null;
+
+        text = text.replaceAll("=", "").trim();
+        if (text.isEmpty()) return new byte[0];
+
+        int buffer = 0;
+        int bufferSize = 0;
+        int byteCount = (text.length() * 5 + 7) / 8;
+        byte[] bytes = new byte[byteCount];
+        int byteIndex = 0;
+
+        for (char c : text.toCharArray()) {
+            int value = BASE32_LOOKUP[c];
+            if (value == 0 && c != 'A') continue; // 跳过非法字符
+
+            buffer = (buffer << 5) | value;
+            bufferSize += 5;
+
+            if (bufferSize >= 8) {
+                bufferSize -= 8;
+                bytes[byteIndex++] = (byte) ((buffer >> bufferSize) & 0xFF);
+            }
+        }
+
+        // 处理最后一个字节
+        if (bufferSize > 0) {
+            bytes[byteIndex] = (byte) ((buffer << (8 - bufferSize)) & 0xFF);
+        }
+
+        return bytes;
+    }
+
+    /**
+     * Base32 编码（String 转 String）
+     */
+    public static String encode(String text) {
+        if (text == null) return null;
+        return encodeBytesToString(text.getBytes(StandardCharsets.UTF_8));
+    }
+
+    /**
+     * Base32 解码（String 转 String）
+     */
+    public static String decode(String base32Text) {
+        if (base32Text == null) return null;
+        byte[] bytes = decodeStringToBytes(base32Text);
+        return new String(bytes, StandardCharsets.UTF_8);
+    }
+
+}

sa-token-doc/up/password-secure.md

@@ -76,6 +76,22 @@ String text2 = SaBase64Util.decode(base64Text);
 System.out.println("Base64解码后：" + text2); 
 ```
 
+
+### Base32编码与解码
+``` java
+// 文本
+String text = "Sa-Token 一个轻量级java权限认证框架";
+
+// 使用Base32编码
+String base32Text = SaBase32Util.encode(text);
+System.out.println("Base32编码后：" + base32Text);
+
+// 使用Base32解码
+String text2 = SaBase32Util.decode(base32Text);
+System.out.println("Base32解码后：" + text2); 
+```
+
+
 ### BCrypt加密
 由它加密的文件可在所有支持的操作系统和处理器上进行转移