diff --git a/hutool-core/src/main/java/cn/hutool/core/stream/FastStream.java b/hutool-core/src/main/java/cn/hutool/core/stream/FastStream.java
index 04df601b9..e6aac7805 100644
--- a/hutool-core/src/main/java/cn/hutool/core/stream/FastStream.java
+++ b/hutool-core/src/main/java/cn/hutool/core/stream/FastStream.java
@@ -3,6 +3,7 @@ package cn.hutool.core.stream;
 
 import cn.hutool.core.lang.Console;
 import cn.hutool.core.lang.Opt;
+import cn.hutool.core.text.StrUtil;
 
 import java.util.*;
 import java.util.concurrent.atomic.AtomicInteger;
@@ -56,6 +57,7 @@ public class FastStream<T> implements Stream<T>, Iterable<T> {
 	 */
 	public static <T> FastStreamBuilder<T> builder() {
 		return new FastStreamBuilder<T>() {
+			private static final long serialVersionUID = 1L;
 			private final Builder<T> streamBuilder = Stream.builder();
 
 			@Override
@@ -133,9 +135,9 @@ public class FastStream<T> implements Stream<T>, Iterable<T> {
 	 * </p>
 	 *
 	 * @param <T>     元素类型
-	 * @param hasNext 条件值
 	 * @param seed    初始值
-	 * @param f       用上一个元素作为参数执行并返回一个新的元素
+	 * @param hasNext 条件值
+	 * @param next    用上一个元素作为参数执行并返回一个新的元素
 	 * @return 无限有序流
 	 */
 	public static <T> FastStream<T> iterate(T seed, Predicate<? super T> hasNext, UnaryOperator<T> next) {
@@ -650,6 +652,7 @@ public class FastStream<T> implements Stream<T>, Iterable<T> {
 	 * }</pre>
 	 */
 	public <A> A[] toArray(IntFunction<A[]> generator) {
+		//noinspection SuspiciousToArrayCall
 		return stream.toArray(generator);
 	}
 
@@ -1083,7 +1086,10 @@ public class FastStream<T> implements Stream<T>, Iterable<T> {
 	 */
 	@Override
 	public boolean equals(Object obj) {
-		return stream.equals(obj);
+		if (obj instanceof Stream) {
+			return stream.equals(obj);
+		}
+		return false;
 	}
 
 	/**
@@ -1143,7 +1149,7 @@ public class FastStream<T> implements Stream<T>, Iterable<T> {
 	 * @return 拼接后的字符串
 	 */
 	public String join() {
-		return join("");
+		return join(StrUtil.EMPTY);
 	}
 
 	/**
@@ -1153,7 +1159,7 @@ public class FastStream<T> implements Stream<T>, Iterable<T> {
 	 * @return 拼接后的字符串
 	 */
 	public String join(CharSequence delimiter) {
-		return join(delimiter, "", "");
+		return join(delimiter, StrUtil.EMPTY, StrUtil.EMPTY);
 	}
 
 	/**
@@ -1336,16 +1342,6 @@ public class FastStream<T> implements Stream<T>, Iterable<T> {
 
 	public interface FastStreamBuilder<T> extends Consumer<T>, cn.hutool.core.builder.Builder<FastStream<T>> {
 
-		/**
-		 * Adds an element to the stream being built.
-		 *
-		 * @param t the element to add
-		 * @throws IllegalStateException if the builder has already transitioned to
-		 *                               the built state
-		 */
-		@Override
-		void accept(T t);
-
 		/**
 		 * Adds an element to the stream being built.
 		 *
@@ -1363,18 +1359,6 @@ public class FastStream<T> implements Stream<T>, Iterable<T> {
 			accept(t);
 			return this;
 		}
-
-		/**
-		 * Builds the stream, transitioning this builder to the built state.
-		 * An {@code IllegalStateException} is thrown if there are further attempts
-		 * to operate on the builder after it has entered the built state.
-		 *
-		 * @return the built stream
-		 * @throws IllegalStateException if the builder has already transitioned to
-		 *                               the built state
-		 */
-		FastStream<T> build();
-
 	}
 
 }
diff --git a/hutool-core/src/test/java/cn/hutool/core/stream/FastStreamTest.java b/hutool-core/src/test/java/cn/hutool/core/stream/FastStreamTest.java
index 18dfd1380..b4060d6b9 100644
--- a/hutool-core/src/test/java/cn/hutool/core/stream/FastStreamTest.java
+++ b/hutool-core/src/test/java/cn/hutool/core/stream/FastStreamTest.java
@@ -65,7 +65,10 @@ public class FastStreamTest {
 		List<Integer> orders = Arrays.asList(1, 2, 3);
 		List<String> list = Arrays.asList("dromara", "hutool", "sweet");
 		Map<Integer, String> toZip = FastStream.of(orders).toZip(list);
-		Assert.assertEquals(new HashMap<Integer, String>() {{
+		Assert.assertEquals(new HashMap<Integer, String>() {
+			private static final long serialVersionUID = 1L;
+
+			{
 			put(1, "dromara");
 			put(2, "hutool");
 			put(3, "sweet");
@@ -85,7 +88,10 @@ public class FastStreamTest {
 	public void testToMap() {
 		List<Integer> list = Arrays.asList(1, 2, 3);
 		Map<String, Integer> identityMap = FastStream.of(list).toMap(String::valueOf);
-		Assert.assertEquals(new HashMap<String, Integer>() {{
+		Assert.assertEquals(new HashMap<String, Integer>() {
+			private static final long serialVersionUID = 1L;
+
+			{
 			put("1", 1);
 			put("2", 2);
 			put("3", 3);
@@ -97,7 +103,10 @@ public class FastStreamTest {
 		List<Integer> list = Arrays.asList(1, 2, 3);
 		Map<String, List<Integer>> group = FastStream.of(list).group(String::valueOf);
 		Assert.assertEquals(
-				new HashMap<String, List<Integer>>() {{
+				new HashMap<String, List<Integer>>() {
+					private static final long serialVersionUID = 1L;
+
+					{
 					put("1", singletonList(1));
 					put("2", singletonList(2));
 					put("3", singletonList(3));
@@ -270,7 +279,7 @@ public class FastStreamTest {
 	}
 
 	@Test
-	void testSub() {
+	public void testSub() {
 		List<Integer> list = Arrays.asList(1, 2, 3, 4, 5);
 		List<List<Integer>> lists = FastStream.of(list).sub(2).map(FastStream::toList).toList();
 		Assert.assertEquals(Arrays.asList(Arrays.asList(1, 2),
@@ -280,7 +289,7 @@ public class FastStreamTest {
 	}
 
 	@Test
-	void testSubList() {
+	public void testSubList() {
 		List<Integer> list = Arrays.asList(1, 2, 3, 4, 5);
 		List<List<Integer>> lists = FastStream.of(list).subList(2).toList();
 		Assert.assertEquals(Arrays.asList(Arrays.asList(1, 2),