!1432 fix: 修复 EnumUtil 递归更新异常 + Cache 高并发双重检查锁逻辑缺陷

Merge pull request !1432 from Busyliu/v5-dev

hutool-cache/src/main/java/cn/hutool/cache/impl/AbstractCache.java

@@ -134,8 +134,12 @@ public abstract class AbstractCache<K, V> implements Cache<K, V> {
 				// issue#3686 由于这个方法内的加锁是get独立锁，不和put锁互斥，而put和pruneCache会修改cacheMap，导致在pruneCache过程中get会有并发问题
 				// 因此此处需要使用带全局锁的get获取值
 				v = get(key, isUpdateLastAccess);
-				v = supplier.callWithRuntimeException();
-				put(key, v, timeout);
+				// fix issue#IDQGP2: 双重检查后若缓存已有值则直接返回，不再调用supplier
+				// 原实现忽略了双重检查的结果，导致高并发下缓存值被重复覆盖
+				if (null == v) {
+					v = supplier.callWithRuntimeException();
+					put(key, v, timeout);
+				}
 			} finally {
 				keyLock.unlock();
 				keyLockMap.remove(key);

hutool-core/src/main/java/cn/hutool/core/collection/BoundedPriorityQueue.java

@@ -26,11 +26,11 @@ public class BoundedPriorityQueue<E> extends PriorityQueue<E>{
 
 	/**
 	 * 构造
-	 * @param capacity 容量
+	 * @param capacity 容量，必须大于0
 	 * @param comparator 比较器
 	 */
 	public BoundedPriorityQueue(int capacity, final Comparator<? super E> comparator) {
-		super(capacity, (o1, o2) -> {
+		super(capacity <= 0 ? 1 : capacity, (o1, o2) -> {
 			int cResult;
 			if(comparator != null) {
 				cResult = comparator.compare(o1, o2);
@@ -53,6 +53,10 @@ public class BoundedPriorityQueue<E> extends PriorityQueue<E>{
 	 */
 	@Override
 	public boolean offer(E e) {
+		if (capacity <= 0) {
+			// 容量为0或负数时，不接受任何元素
+			return false;
+		}
 		if(size() >= capacity) {
 			E head = peek();
 			if (this.comparator().compare(e, head) <= 0){

hutool-core/src/main/java/cn/hutool/core/date/TemporalUtil.java

@@ -127,7 +127,7 @@ public class TemporalUtil {
 	/**
 	 * 偏移到指定的周几
 	 *
-	 * @param temporal   日期或者日期时间
+	 * @param temporal   日期或者日期时间，为{@code null}返回{@code null}
 	 * @param dayOfWeek  周几
 	 * @param <T>        日期类型，如LocalDate或LocalDateTime
 	 * @param isPrevious 是否向前偏移，{@code true}向前偏移，{@code false}向后偏移。
@@ -135,7 +135,10 @@ public class TemporalUtil {
 	 * @since 5.8.0
 	 */
 	@SuppressWarnings("unchecked")
-	public <T extends Temporal> T offset(T temporal, DayOfWeek dayOfWeek, boolean isPrevious) {
+	public static <T extends Temporal> T offset(T temporal, DayOfWeek dayOfWeek, boolean isPrevious) {
+		if (null == temporal) {
+			return null;
+		}
 		return (T) temporal.with(isPrevious ? TemporalAdjusters.previous(dayOfWeek) : TemporalAdjusters.next(dayOfWeek));
 	}
 }

hutool-core/src/main/java/cn/hutool/core/lang/Tuple.java

@@ -33,7 +33,8 @@ public class Tuple extends CloneSupport<Tuple> implements Iterable<Object>, Seri
 	 * @param members 成员数组
 	 */
 	public Tuple(Object... members) {
-		this.members = members;
+		// defensive copy，保证 Tuple 的不可变性，防止外部修改传入数组影响内部状态
+		this.members = members.clone();
 	}
 
 	/**
@@ -51,10 +52,11 @@ public class Tuple extends CloneSupport<Tuple> implements Iterable<Object>, Seri
 	/**
 	 * 获得所有元素
 	 *
-	 * @return 获得所有元素
+	 * @return 获得所有元素的副本
 	 */
 	public Object[] getMembers() {
-		return this.members;
+		// 返回副本而非内部数组引用，防止外部修改破坏 Tuple 的不可变性
+		return this.members.clone();
 	}
 
 	/**

hutool-core/src/main/java/cn/hutool/core/math/Money.java

@@ -621,6 +621,9 @@ public class Money implements Serializable, Comparable<Money> {
 	 * @return 相除后的结果。
 	 */
 	public Money divide(double val) {
+		if (val == 0) {
+			throw new ArithmeticException("Division by zero");
+		}
 		return newMoneyWithSameCurrency(Math.round(cent / val));
 	}
 
@@ -635,7 +638,10 @@ public class Money implements Serializable, Comparable<Money> {
 	 * @return 累除后的结果。
 	 */
 	public Money divideBy(double val) {
-		this.cent = Math.round(this.cent / val);
+
+		if (val == 0) {
+			throw new ArithmeticException("Division by zero");
+		}		this.cent = Math.round(this.cent / val);
 
 		return this;
 	}

hutool-core/src/main/java/cn/hutool/core/util/ArrayUtil.java

@@ -582,6 +582,9 @@ public class ArrayUtil extends PrimitiveArrayUtil {
 	 */
 	public static Object copy(Object src, int srcPos, Object dest, int destPos, int length) {
 		//noinspection SuspiciousSystemArraycopy
+		if (null == src || null == dest) {
+			throw new NullPointerException("Source array and destination array must not be null");
+		}
 		System.arraycopy(src, srcPos, dest, destPos, length);
 		return dest;
 	}
@@ -598,6 +601,9 @@ public class ArrayUtil extends PrimitiveArrayUtil {
 	 */
 	public static Object copy(Object src, Object dest, int length) {
 		//noinspection SuspiciousSystemArraycopy
+		if (null == src || null == dest) {
+			throw new NullPointerException("Source array and destination array must not be null");
+		}
 		System.arraycopy(src, 0, dest, 0, length);
 		return dest;
 	}

hutool-core/src/main/java/cn/hutool/core/util/EnumUtil.java

@@ -480,6 +480,16 @@ public class EnumUtil {
 		if (null == enumClass) {
 			return null;
 		}
-		return CACHE.computeIfAbsent(enumClass, (k) -> enumClass.getEnumConstants());
+		// fix issue#IDQYJK: 避免 ConcurrentHashMap.computeIfAbsent 在枚举类静态初始化时
+		// 递归调用导致 IllegalStateException: Recursive update 的问题
+		// 使用 get + putIfAbsent 替代 computeIfAbsent，安全支持递归场景
+		Enum<?>[] enums = CACHE.get(enumClass);
+		if (null == enums) {
+			enums = enumClass.getEnumConstants();
+			if (null != enums) {
+				CACHE.putIfAbsent(enumClass, enums);
+			}
+		}
+		return enums;
 	}
 }

hutool-core/src/test/java/cn/hutool/core/util/EnumUtilTest.java

@@ -70,6 +70,20 @@ public class EnumUtilTest {
 		assertEquals("type1", enumMap.get("TEST1"));
 	}
 
+	/**
+	 * 测试枚举类静态初始化中调用 EnumUtil 不会导致 Recursive update 异常
+	 * fix issue#IDQYJK
+	 */
+	@Test
+	public void getFieldValuesRecursiveTest() {
+		// SelfRefEnum 在静态初始化时调用了 EnumUtil.getNames，
+		// 修复前会抛出 IllegalStateException: Recursive update
+		// 修复后应正常返回结果
+		List<Object> values = EnumUtil.getFieldValues(SelfRefEnum.class, "label");
+		assertNotNull(values);
+		assertEquals(3, values.size());
+	}
+
 	public enum TestEnum{
 		TEST1("type1"), TEST2("type2"), TEST3("type3");
 
@@ -89,4 +103,24 @@ public class EnumUtilTest {
 			return this.name;
 		}
 	}
+
+	/**
+	 * 静态初始化中使用 EnumUtil 的枚举，用于测试 fix issue#IDQYJK
+	 */
+	public enum SelfRefEnum {
+		A("labelA"), B("labelB"), C("labelC");
+
+		// 静态初始化块中调用 EnumUtil，触发 ConcurrentHashMap.computeIfAbsent 的递归场景
+		static final List<String> NAMES = EnumUtil.getNames(SelfRefEnum.class);
+
+		private final String label;
+
+		SelfRefEnum(String label) {
+			this.label = label;
+		}
+
+		public String getLabel() {
+			return label;
+		}
+	}
 }

hutool-crypto/src/main/java/cn/hutool/crypto/symmetric/RC4.java

@@ -246,7 +246,8 @@ public class RC4 implements Serializable {
 		}
 
 		for (int i = 0; i < SBOX_LENGTH; i++) {
-			j = (j + sbox[i] + (key[i % key.length]) & 0xFF) % SBOX_LENGTH;
+			// fix: 运算符优先级修正，& 0xFF 应先与 key 字节值进行位与运算，再参与加法，避免有符号 byte 导致计算偏差
+			j = (j + sbox[i] + (key[i % key.length] & 0xFF)) % SBOX_LENGTH;
 			swap(i, j, sbox);
 		}
 		return sbox;