diff --git a/src/test/java/com/yexuejc/base/encrypt/AESEnhancedTest.java b/src/test/java/com/yexuejc/base/encrypt/AESEnhancedTest.java
new file mode 100644
index 0000000..159a60b
--- /dev/null
+++ b/src/test/java/com/yexuejc/base/encrypt/AESEnhancedTest.java
@@ -0,0 +1,232 @@
+package com.yexuejc.base.encrypt;
+
+import com.yexuejc.base.exception.BaseException;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.api.Assertions;
+
+import java.nio.charset.StandardCharsets;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+/**
+ * AES加密增强测试类 - 验证优化后的安全性和功能
+ *
+ * @author optimization
+ * @date 2025/09/23
+ */
+@DisplayName("AES加密增强测试")
+class AESEnhancedTest {
+
+    private AES aes;
+
+    @BeforeEach
+    void setUp() {
+        aes = AES.builder();
+    }
+
+    @Test
+    @DisplayName("测试密钥和IV必须设置")
+    void testKeyAndIvRequired() {
+        // 测试未设置密钥时抛出异常
+        IllegalStateException exception = assertThrows(IllegalStateException.class, () -> {
+            aes.encrypt("test data");
+        });
+        assertTrue(exception.getMessage().contains("AES密钥未设置"));
+    }
+
+    @Test
+    @DisplayName("测试密钥长度验证")
+    void testKeyLengthValidation() {
+        // 测试无效密钥长度
+        IllegalArgumentException exception = assertThrows(IllegalArgumentException.class, () -> {
+            aes.setKey("short");
+        });
+        assertTrue(exception.getMessage().contains("AES密钥长度必须是16、24或32字节"));
+
+        // 测试有效密钥长度
+        assertDoesNotThrow(() -> {
+            aes.setKey("1234567890123456"); // 16字节
+            aes.setKey("123456789012345678901234"); // 24字节
+            aes.setKey("12345678901234567890123456789012"); // 32字节
+        });
+    }
+
+    @Test
+    @DisplayName("测试IV长度验证")
+    void testIvLengthValidation() {
+        // 设置有效密钥
+        aes.setKey("1234567890123456");
+
+        // 测试无效IV长度
+        IllegalArgumentException exception = assertThrows(IllegalArgumentException.class, () -> {
+            aes.setIv("short");
+        });
+        assertTrue(exception.getMessage().contains("AES初始向量长度必须是16字节"));
+
+        // 测试有效IV长度
+        assertDoesNotThrow(() -> {
+            aes.setIv("1234567890123456"); // 16字节
+        });
+    }
+
+    @Test
+    @DisplayName("测试输入参数验证")
+    void testInputValidation() {
+        aes.setKey("1234567890123456")
+           .setIv("1234567890123456")
+           .setAlgorithm(AES.ALGORITHM.AES_CBC_PKCS5Padding);
+
+        // 测试空输入
+        IllegalArgumentException encryptException = assertThrows(IllegalArgumentException.class, () -> {
+            aes.encrypt(null);
+        });
+        assertTrue(encryptException.getMessage().contains("加密数据不能为空"));
+
+        IllegalArgumentException decryptException = assertThrows(IllegalArgumentException.class, () -> {
+            aes.decrypt(null);
+        });
+        assertTrue(decryptException.getMessage().contains("解密数据不能为空"));
+    }
+
+    @Test
+    @DisplayName("测试字符集设置验证")
+    void testCharsetValidation() {
+        IllegalArgumentException exception = assertThrows(IllegalArgumentException.class, () -> {
+            aes.setCharset(null);
+        });
+        assertTrue(exception.getMessage().contains("字符集不能为空"));
+
+        // 测试有效字符集设置
+        assertDoesNotThrow(() -> {
+            aes.setCharset(StandardCharsets.UTF_8);
+        });
+    }
+
+    @Test
+    @DisplayName("测试ECB模式不需要IV")
+    void testECBModeWithoutIV() throws BaseException {
+        String data = "Hello World!";
+        aes.setKey("1234567890123456")
+           .setAlgorithm(AES.ALGORITHM.AES_ECB_PKCS5Padding);
+
+        // ECB模式不需要IV
+        String encrypted = aes.encrypt(data);
+        assertNotNull(encrypted);
+        assertFalse(encrypted.isEmpty());
+
+        String decrypted = aes.decrypt(encrypted);
+        assertEquals(data, decrypted);
+    }
+
+    @Test
+    @DisplayName("测试完整的加密解密流程")
+    void testCompleteEncryptDecryptFlow() throws BaseException {
+        String originalData = "这是一个测试字符串包含中文！";
+        
+        aes.setKey("1234567890123456")
+           .setIv("1234567890123456")
+           .setAlgorithm(AES.ALGORITHM.AES_CBC_PKCS5Padding)
+           .setCharset(StandardCharsets.UTF_8);
+
+        String encrypted = aes.encrypt(originalData);
+        assertNotNull(encrypted);
+        assertNotEquals(originalData, encrypted);
+
+        String decrypted = aes.decrypt(encrypted);
+        assertEquals(originalData, decrypted);
+    }
+
+    @Test
+    @DisplayName("测试不同AES算法模式")
+    void testDifferentAlgorithms() throws BaseException {
+        String data = "Test Data";
+        String key = "1234567890123456";
+        String iv = "1234567890123456";
+
+        AES.ALGORITHM[] algorithms = {
+            AES.ALGORITHM.AES_CBC_PKCS5Padding,
+            AES.ALGORITHM.AES_OFB_PKCS5Padding,
+            AES.ALGORITHM.AES_ECB_PKCS5Padding
+        };
+
+        for (AES.ALGORITHM algorithm : algorithms) {
+            AES testAes = AES.builder()
+                .setKey(key)
+                .setAlgorithm(algorithm);
+                
+            if (!algorithm.code.contains("ECB")) {
+                testAes.setIv(iv);
+            }
+
+            String encrypted = testAes.encrypt(data);
+            String decrypted = testAes.decrypt(encrypted);
+            
+            assertEquals(data, decrypted, "Algorithm " + algorithm.code + " failed");
+        }
+    }
+
+    @Test
+    @DisplayName("测试建造者模式")
+    void testBuilderPattern() {
+        AES aes1 = AES.builder();
+        AES aes2 = AES.builder();
+        
+        // 现在返回不同的实例，避免状态共享
+        assertNotNull(aes1);
+        assertNotNull(aes2);
+        assertNotSame(aes1, aes2); // 确认不是单例
+    }
+
+    @Test
+    @DisplayName("测试解密异常处理")
+    void testDecryptErrorHandling() {
+        aes.setKey("1234567890123456")
+           .setIv("1234567890123456")
+           .setAlgorithm(AES.ALGORITHM.AES_CBC_PKCS5Padding);
+
+        // 测试无效Base64数据
+        BaseException exception = assertThrows(BaseException.class, () -> {
+            aes.decrypt("invalid_base64_data");
+        });
+        assertNotNull(exception.getErrorCode());
+    }
+
+    @Test
+    @DisplayName("测试不同密钥长度")
+    void testDifferentKeyLengths() throws BaseException {
+        String data = "Test Data";
+        String iv = "1234567890123456";
+
+        // 测试16字节密钥
+        AES aes16 = AES.builder()
+            .setKey("1234567890123456")
+            .setIv(iv)
+            .setAlgorithm(AES.ALGORITHM.AES_CBC_PKCS5Padding);
+        
+        String encrypted16 = aes16.encrypt(data);
+        String decrypted16 = aes16.decrypt(encrypted16);
+        assertEquals(data, decrypted16);
+
+        // 测试24字节密钥
+        AES aes24 = AES.builder()
+            .setKey("123456789012345678901234")
+            .setIv(iv)
+            .setAlgorithm(AES.ALGORITHM.AES_CBC_PKCS5Padding);
+        
+        String encrypted24 = aes24.encrypt(data);
+        String decrypted24 = aes24.decrypt(encrypted24);
+        assertEquals(data, decrypted24);
+
+        // 测试32字节密钥
+        AES aes32 = AES.builder()
+            .setKey("12345678901234567890123456789012")
+            .setIv(iv)
+            .setAlgorithm(AES.ALGORITHM.AES_CBC_PKCS5Padding);
+        
+        String encrypted32 = aes32.encrypt(data);
+        String decrypted32 = aes32.decrypt(encrypted32);
+        assertEquals(data, decrypted32);
+    }
+}
\ No newline at end of file
diff --git a/src/test/java/com/yexuejc/base/util/ObjUtilEnhancedTest.java b/src/test/java/com/yexuejc/base/util/ObjUtilEnhancedTest.java
new file mode 100644
index 0000000..4f26211
--- /dev/null
+++ b/src/test/java/com/yexuejc/base/util/ObjUtilEnhancedTest.java
@@ -0,0 +1,237 @@
+package com.yexuejc.base.util;
+
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.DisplayName;
+
+import java.util.Arrays;
+import java.util.List;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+/**
+ * ObjUtil增强测试类 - 验证优化后的异常处理和功能
+ *
+ * @author optimization
+ * @date 2025/09/23
+ */
+@DisplayName("ObjUtil增强测试")
+class ObjUtilEnhancedTest {
+
+    @Test
+    @DisplayName("测试基本字段复制功能")
+    void testBasicFieldCopy() throws Exception {
+        SourceObject source = new SourceObject();
+        source.setName("Test Name");
+        source.setAge(25);
+        source.setEmail("test@example.com");
+
+        TargetObject target = ObjUtil.copy(source, TargetObject.class, null, null);
+
+        assertNotNull(target);
+        assertEquals(source.getName(), target.getName());
+        assertEquals(source.getAge(), target.getAge());
+        assertEquals(source.getEmail(), target.getEmail());
+    }
+
+    @Test
+    @DisplayName("测试包含字段过滤")
+    void testIncludeFieldFiltering() throws Exception {
+        SourceObject source = new SourceObject();
+        source.setName("Test Name");
+        source.setAge(25);
+        source.setEmail("test@example.com");
+
+        List<String> includeFields = Arrays.asList("name", "age");
+        TargetObject target = ObjUtil.copy(source, TargetObject.class, includeFields, null);
+
+        assertNotNull(target);
+        assertEquals(source.getName(), target.getName());
+        assertEquals(source.getAge(), target.getAge());
+        assertNull(target.getEmail()); // 不在包含列表中
+    }
+
+    @Test
+    @DisplayName("测试排除字段过滤")
+    void testExcludeFieldFiltering() throws Exception {
+        SourceObject source = new SourceObject();
+        source.setName("Test Name");
+        source.setAge(25);
+        source.setEmail("test@example.com");
+
+        List<String> excludeFields = Arrays.asList("email");
+        TargetObject target = ObjUtil.copy(source, TargetObject.class, null, excludeFields);
+
+        assertNotNull(target);
+        assertEquals(source.getName(), target.getName());
+        assertEquals(source.getAge(), target.getAge());
+        assertNull(target.getEmail()); // 被排除
+    }
+
+    @Test
+    @DisplayName("测试使用Setter方法复制")
+    void testCopyWithSetter() throws Exception {
+        SourceObject source = new SourceObject();
+        source.setName("Test Name");
+        source.setAge(25);
+
+        TargetObjectWithSetter target = ObjUtil.copy(source, TargetObjectWithSetter.class, true);
+
+        assertNotNull(target);
+        assertEquals(source.getName(), target.getName());
+        assertEquals(source.getAge(), target.getAge());
+    }
+
+    @Test
+    @DisplayName("测试字段不匹配的处理")
+    void testFieldMismatchHandling() throws Exception {
+        SourceObjectWithExtraField source = new SourceObjectWithExtraField();
+        source.setName("Test Name");
+        source.setAge(25);
+        source.setExtraField("Extra Value");
+
+        // 目标类没有extraField字段
+        TargetObject target = ObjUtil.copy(source, TargetObject.class, null, null);
+
+        assertNotNull(target);
+        assertEquals(source.getName(), target.getName());
+        assertEquals(source.getAge(), target.getAge());
+        // extraField应该被忽略，不会导致异常
+    }
+
+    @Test
+    @DisplayName("测试空源对象处理")
+    void testNullSourceHandling() {
+        assertThrows(NullPointerException.class, () -> {
+            ObjUtil.copy(null, TargetObject.class, null, null);
+        });
+    }
+
+    @Test
+    @DisplayName("测试获取所有字段功能")
+    void testGetAllFields() {
+        List<java.lang.reflect.Field> fields = ObjUtil.getAllFields(ChildObject.class);
+        
+        assertNotNull(fields);
+        assertTrue(fields.size() >= 3); // 至少包含child字段和父类的两个字段
+        
+        // 验证包含父类字段
+        boolean hasParentField1 = fields.stream().anyMatch(f -> "parentField1".equals(f.getName()));
+        boolean hasParentField2 = fields.stream().anyMatch(f -> "parentField2".equals(f.getName()));
+        boolean hasChildField = fields.stream().anyMatch(f -> "childField".equals(f.getName()));
+        
+        assertTrue(hasParentField1);
+        assertTrue(hasParentField2);
+        assertTrue(hasChildField);
+    }
+
+    @Test
+    @DisplayName("测试获取所有Getter方法功能")
+    void testGetAllGetterMethods() {
+        List<java.lang.reflect.Method> methods = ObjUtil.getAllGetterMethods(ChildObject.class, "get");
+        
+        assertNotNull(methods);
+        assertTrue(methods.size() >= 3); // 至少包含三个getter方法
+        
+        // 验证包含父类方法
+        boolean hasGetParentField1 = methods.stream().anyMatch(m -> "getParentField1".equals(m.getName()));
+        boolean hasGetParentField2 = methods.stream().anyMatch(m -> "getParentField2".equals(m.getName()));
+        boolean hasGetChildField = methods.stream().anyMatch(m -> "getChildField".equals(m.getName()));
+        
+        assertTrue(hasGetParentField1);
+        assertTrue(hasGetParentField2);
+        assertTrue(hasGetChildField);
+    }
+
+    @Test
+    @DisplayName("测试首字母小写工具方法")
+    void testLowerCaseFirstChar() {
+        assertEquals("test", ObjUtil.lowerCaseFirstChar("Test"));
+        assertEquals("tEST", ObjUtil.lowerCaseFirstChar("TEST"));
+        assertEquals("", ObjUtil.lowerCaseFirstChar(""));
+        assertNull(ObjUtil.lowerCaseFirstChar(null));
+        assertEquals("a", ObjUtil.lowerCaseFirstChar("A"));
+    }
+
+    @Test
+    @DisplayName("测试目标类没有默认构造函数的情况")
+    void testTargetClassWithoutDefaultConstructor() {
+        SourceObject source = new SourceObject();
+        source.setName("Test");
+
+        assertThrows(Exception.class, () -> {
+            ObjUtil.copy(source, ClassWithoutDefaultConstructor.class, null, null);
+        });
+    }
+
+    // 测试用的内部类
+
+    static class SourceObject {
+        private String name;
+        private Integer age;
+        private String email;
+
+        public String getName() { return name; }
+        public void setName(String name) { this.name = name; }
+        public Integer getAge() { return age; }
+        public void setAge(Integer age) { this.age = age; }
+        public String getEmail() { return email; }
+        public void setEmail(String email) { this.email = email; }
+    }
+
+    static class SourceObjectWithExtraField extends SourceObject {
+        private String extraField;
+
+        public String getExtraField() { return extraField; }
+        public void setExtraField(String extraField) { this.extraField = extraField; }
+    }
+
+    static class TargetObject {
+        private String name;
+        private Integer age;
+        private String email;
+
+        public String getName() { return name; }
+        public void setName(String name) { this.name = name; }
+        public Integer getAge() { return age; }
+        public void setAge(Integer age) { this.age = age; }
+        public String getEmail() { return email; }
+        public void setEmail(String email) { this.email = email; }
+    }
+
+    static class TargetObjectWithSetter {
+        private String name;
+        private Integer age;
+
+        public String getName() { return name; }
+        public void setName(String name) { this.name = name; }
+        public Integer getAge() { return age; }
+        public void setAge(Integer age) { this.age = age; }
+    }
+
+    static class ParentObject {
+        private String parentField1;
+        private String parentField2;
+
+        public String getParentField1() { return parentField1; }
+        public void setParentField1(String parentField1) { this.parentField1 = parentField1; }
+        public String getParentField2() { return parentField2; }
+        public void setParentField2(String parentField2) { this.parentField2 = parentField2; }
+    }
+
+    static class ChildObject extends ParentObject {
+        private String childField;
+
+        public String getChildField() { return childField; }
+        public void setChildField(String childField) { this.childField = childField; }
+    }
+
+    static class ClassWithoutDefaultConstructor {
+        private String name;
+
+        public ClassWithoutDefaultConstructor(String name) {
+            this.name = name;
+        }
+
+        public String getName() { return name; }
+    }
+}
\ No newline at end of file
diff --git a/src/test/java/com/yexuejc/base/util/StrUtilEnhancedTest.java b/src/test/java/com/yexuejc/base/util/StrUtilEnhancedTest.java
new file mode 100644
index 0000000..7dd15f4
--- /dev/null
+++ b/src/test/java/com/yexuejc/base/util/StrUtilEnhancedTest.java
@@ -0,0 +1,288 @@
+package com.yexuejc.base.util;
+
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.RepeatedTest;
+
+import java.util.HashSet;
+import java.util.Set;
+import java.util.concurrent.ExecutorService;
+import java.util.concurrent.Executors;
+import java.util.concurrent.TimeUnit;
+import java.util.concurrent.atomic.AtomicBoolean;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+/**
+ * StrUtil增强测试类 - 验证优化后的性能和线程安全性
+ *
+ * @author optimization
+ * @date 2025/09/23
+ */
+@DisplayName("StrUtil增强测试")
+class StrUtilEnhancedTest {
+
+    @Test
+    @DisplayName("测试MD5计算的一致性")
+    void testMD5Consistency() {
+        String input = "Hello World!";
+        String expected = "ed076287532e86365e841e92bfc50d8c"; // 已知MD5值
+
+        String result1 = StrUtil.toMD5(input);
+        String result2 = StrUtil.toMD5(input);
+        
+        assertEquals(expected, result1);
+        assertEquals(result1, result2);
+    }
+
+    @Test
+    @DisplayName("测试SHA256计算的一致性")
+    void testSHA256Consistency() {
+        String input = "Hello World!";
+        String expected = "7f83b1657ff1fc53b92dc18148a1d65dfc2d4b1fa3d677284addd200126d9069"; // 已知SHA256值
+
+        String result1 = StrUtil.toSHA256(input);
+        String result2 = StrUtil.toSHA256(input);
+        
+        assertEquals(expected, result1);
+        assertEquals(result1, result2);
+    }
+
+    @Test
+    @DisplayName("测试MD5处理null值")
+    void testMD5WithNull() {
+        assertNull(StrUtil.toMD5(null));
+    }
+
+    @Test
+    @DisplayName("测试SHA256处理null值")
+    void testSHA256WithNull() {
+        assertNull(StrUtil.toSHA256(null));
+    }
+
+    @Test
+    @DisplayName("测试不支持的SHA算法")
+    void testUnsupportedSHAAlgorithm() {
+        String result = StrUtil.toSHA("test", "INVALID_ALGORITHM");
+        assertNull(result);
+    }
+
+    @Test
+    @DisplayName("测试中文字符的MD5计算")
+    void testMD5WithChinese() {
+        String input = "你好世界";
+        String result = StrUtil.toMD5(input);
+        
+        assertNotNull(result);
+        assertEquals(32, result.length()); // MD5长度应为32
+        assertTrue(result.matches("[a-f0-9]+"));
+    }
+
+    @Test
+    @DisplayName("测试中文字符的SHA256计算")
+    void testSHA256WithChinese() {
+        String input = "你好世界";
+        String result = StrUtil.toSHA256(input);
+        
+        assertNotNull(result);
+        assertEquals(64, result.length()); // SHA256长度应为64
+        assertTrue(result.matches("[a-f0-9]+"));
+    }
+
+    @Test
+    @DisplayName("测试长字符串的MD5计算")
+    void testMD5WithLongString() {
+        StringBuilder longString = new StringBuilder();
+        for (int i = 0; i < 10000; i++) {
+            longString.append("abcdefghij");
+        }
+        
+        String result = StrUtil.toMD5(longString.toString());
+        assertNotNull(result);
+        assertEquals(32, result.length());
+    }
+
+    @RepeatedTest(10)
+    @DisplayName("测试SecureRandom生成的随机性")
+    void testCodeIdRandomness() {
+        String id = "12345678901234567890123456789012"; // 32位ID
+        
+        String coded1 = StrUtil.codeId(id);
+        String coded2 = StrUtil.codeId(id);
+        
+        assertEquals(64, coded1.length());
+        assertEquals(64, coded2.length());
+        
+        // 由于使用SecureRandom，两次编码结果应该不同
+        assertNotEquals(coded1, coded2);
+        
+        // 解码后应该得到原始ID
+        String decoded1 = StrUtil.decodeId(coded1);
+        String decoded2 = StrUtil.decodeId(coded2);
+        
+        assertEquals(id, decoded1);
+        assertEquals(id, decoded2);
+    }
+
+    @Test
+    @DisplayName("测试codeId处理无效输入")
+    void testCodeIdWithInvalidInput() {
+        // 测试null
+        assertNull(StrUtil.codeId(null));
+        
+        // 测试长度不是32的字符串
+        String shortId = "short";
+        assertEquals(shortId, StrUtil.codeId(shortId));
+        
+        String longId = "this_is_a_very_long_string_that_exceeds_32_characters";
+        assertEquals(longId, StrUtil.codeId(longId));
+    }
+
+    @Test
+    @DisplayName("测试decodeId处理无效输入")
+    void testDecodeIdWithInvalidInput() {
+        // 测试null
+        assertNull(StrUtil.decodeId(null));
+        
+        // 测试长度不是64的字符串
+        String shortCoded = "short";
+        assertEquals(shortCoded, StrUtil.decodeId(shortCoded));
+        
+        String longCoded = "this_is_a_very_long_string_that_exceeds_64_characters_and_should_be_returned_as_is";
+        assertEquals(longCoded, StrUtil.decodeId(longCoded));
+    }
+
+    @Test
+    @DisplayName("测试线程安全性 - MD5计算")
+    void testMD5ThreadSafety() throws InterruptedException {
+        final int threadCount = 20;
+        final int iterationsPerThread = 100;
+        final String testString = "Thread Safety Test";
+        final String expectedMD5 = StrUtil.toMD5(testString);
+        
+        ExecutorService executor = Executors.newFixedThreadPool(threadCount);
+        AtomicBoolean hasError = new AtomicBoolean(false);
+        
+        for (int i = 0; i < threadCount; i++) {
+            executor.submit(() -> {
+                for (int j = 0; j < iterationsPerThread; j++) {
+                    String result = StrUtil.toMD5(testString);
+                    if (!expectedMD5.equals(result)) {
+                        hasError.set(true);
+                        break;
+                    }
+                }
+            });
+        }
+        
+        executor.shutdown();
+        assertTrue(executor.awaitTermination(10, TimeUnit.SECONDS));
+        assertFalse(hasError.get(), "MD5计算在多线程环境下出现不一致结果");
+    }
+
+    @Test
+    @DisplayName("测试线程安全性 - SHA256计算")
+    void testSHA256ThreadSafety() throws InterruptedException {
+        final int threadCount = 20;
+        final int iterationsPerThread = 100;
+        final String testString = "Thread Safety Test";
+        final String expectedSHA256 = StrUtil.toSHA256(testString);
+        
+        ExecutorService executor = Executors.newFixedThreadPool(threadCount);
+        AtomicBoolean hasError = new AtomicBoolean(false);
+        
+        for (int i = 0; i < threadCount; i++) {
+            executor.submit(() -> {
+                for (int j = 0; j < iterationsPerThread; j++) {
+                    String result = StrUtil.toSHA256(testString);
+                    if (!expectedSHA256.equals(result)) {
+                        hasError.set(true);
+                        break;
+                    }
+                }
+            });
+        }
+        
+        executor.shutdown();
+        assertTrue(executor.awaitTermination(10, TimeUnit.SECONDS));
+        assertFalse(hasError.get(), "SHA256计算在多线程环境下出现不一致结果");
+    }
+
+    @Test
+    @DisplayName("测试线程安全性 - codeId生成")
+    void testCodeIdThreadSafety() throws InterruptedException {
+        final int threadCount = 10;
+        final int iterationsPerThread = 50;
+        final String testId = "12345678901234567890123456789012";
+        
+        ExecutorService executor = Executors.newFixedThreadPool(threadCount);
+        Set<String> results = new HashSet<>();
+        AtomicBoolean hasError = new AtomicBoolean(false);
+        
+        for (int i = 0; i < threadCount; i++) {
+            executor.submit(() -> {
+                for (int j = 0; j < iterationsPerThread; j++) {
+                    String coded = StrUtil.codeId(testId);
+                    String decoded = StrUtil.decodeId(coded);
+                    
+                    if (!testId.equals(decoded)) {
+                        hasError.set(true);
+                        break;
+                    }
+                    
+                    synchronized (results) {
+                        results.add(coded);
+                    }
+                }
+            });
+        }
+        
+        executor.shutdown();
+        assertTrue(executor.awaitTermination(10, TimeUnit.SECONDS));
+        assertFalse(hasError.get(), "codeId在多线程环境下解码失败");
+        
+        // 验证生成的编码都是唯一的（由于使用SecureRandom）
+        assertEquals(threadCount * iterationsPerThread, results.size(), 
+                     "生成的编码应该都是唯一的");
+    }
+
+    @Test
+    @DisplayName("测试性能 - MD5计算")
+    void testMD5Performance() {
+        String testString = "Performance test string with some content to hash";
+        long startTime = System.nanoTime();
+        
+        for (int i = 0; i < 10000; i++) {
+            StrUtil.toMD5(testString);
+        }
+        
+        long endTime = System.nanoTime();
+        long duration = endTime - startTime;
+        
+        // 确保性能在合理范围内（这里只是确保能完成，具体时间取决于硬件）
+        assertTrue(duration > 0, "MD5计算应该花费一些时间");
+        
+        // 可以添加更具体的性能断言，但要考虑不同硬件的差异
+        System.out.println("MD5 10000次计算耗时: " + duration / 1_000_000 + "ms");
+    }
+
+    @Test
+    @DisplayName("测试边界值")
+    void testBoundaryValues() {
+        // 测试空字符串
+        String emptyResult = StrUtil.toMD5("");
+        assertNotNull(emptyResult);
+        assertEquals(32, emptyResult.length());
+        
+        // 测试单字符
+        String singleCharResult = StrUtil.toMD5("a");
+        assertNotNull(singleCharResult);
+        assertEquals(32, singleCharResult.length());
+        
+        // 测试特殊字符
+        String specialCharResult = StrUtil.toMD5("!@#$%^&*()");
+        assertNotNull(specialCharResult);
+        assertEquals(32, specialCharResult.length());
+    }
+}
\ No newline at end of file