diff --git a/hutool-core/src/main/java/cn/hutool/core/collection/IterChain.java b/hutool-core/src/main/java/cn/hutool/core/collection/IterChain.java
index ec73ef039..7d4b93932 100644
--- a/hutool-core/src/main/java/cn/hutool/core/collection/IterChain.java
+++ b/hutool-core/src/main/java/cn/hutool/core/collection/IterChain.java
@@ -26,7 +26,8 @@ public class IterChain<T> implements Iterator<T>, Chain<Iterator<T>, IterChain<T
 	}
 
 	/**
-	 * Creates new composite iterator with provided iterators.
+	 * 构造
+	 * @param iterators 多个{@link Iterator}
 	 */
 	@SafeVarargs
 	public IterChain(Iterator<T>... iterators) {
diff --git a/hutool-core/src/main/java/cn/hutool/core/convert/impl/ArrayConverter.java b/hutool-core/src/main/java/cn/hutool/core/convert/impl/ArrayConverter.java
index b0793d50c..ae4d72fe2 100644
--- a/hutool-core/src/main/java/cn/hutool/core/convert/impl/ArrayConverter.java
+++ b/hutool-core/src/main/java/cn/hutool/core/convert/impl/ArrayConverter.java
@@ -5,6 +5,7 @@ import cn.hutool.core.convert.AbstractConverter;
 import cn.hutool.core.convert.Convert;
 import cn.hutool.core.util.ArrayUtil;
 import cn.hutool.core.util.ByteUtil;
+import cn.hutool.core.util.CharUtil;
 import cn.hutool.core.util.ObjectUtil;
 import cn.hutool.core.util.StrUtil;
 
@@ -124,7 +125,7 @@ public class ArrayConverter extends AbstractConverter<Object> {
 			}
 
 			// 单纯字符串情况下按照逗号分隔后劈开
-			final String[] strings = StrUtil.split(value.toString(), StrUtil.COMMA);
+			final String[] strings = StrUtil.splitToArray(value.toString(), CharUtil.COMMA);
 			return convertArrayToArray(strings);
 		}
 
diff --git a/hutool-core/src/main/java/cn/hutool/core/exceptions/ExceptionUtil.java b/hutool-core/src/main/java/cn/hutool/core/exceptions/ExceptionUtil.java
index e9cf0b304..e86fd6428 100644
--- a/hutool-core/src/main/java/cn/hutool/core/exceptions/ExceptionUtil.java
+++ b/hutool-core/src/main/java/cn/hutool/core/exceptions/ExceptionUtil.java
@@ -1,7 +1,7 @@
 package cn.hutool.core.exceptions;
 
-import cn.hutool.core.collection.CollUtil;
 import cn.hutool.core.io.FastByteArrayOutputStream;
+import cn.hutool.core.map.MapUtil;
 import cn.hutool.core.util.ArrayUtil;
 import cn.hutool.core.util.ReflectUtil;
 import cn.hutool.core.util.StrUtil;
@@ -246,7 +246,7 @@ public class ExceptionUtil {
 			length = limit;
 		}
 
-		if (CollUtil.isNotEmpty(replaceCharToStrMap)) {
+		if (MapUtil.isNotEmpty(replaceCharToStrMap)) {
 			final StringBuilder sb = StrUtil.builder();
 			char c;
 			String value;
diff --git a/hutool-core/src/main/java/cn/hutool/core/net/Ipv4Util.java b/hutool-core/src/main/java/cn/hutool/core/net/Ipv4Util.java
index 2ae114f4e..881670159 100644
--- a/hutool-core/src/main/java/cn/hutool/core/net/Ipv4Util.java
+++ b/hutool-core/src/main/java/cn/hutool/core/net/Ipv4Util.java
@@ -56,11 +56,11 @@ public class Ipv4Util {
 	public static List<String> list(String ipRange, boolean isAll) {
 		if (ipRange.contains(IP_SPLIT_MARK)) {
 			// X.X.X.X-X.X.X.X
-			final String[] range = StrUtil.split(ipRange, IP_SPLIT_MARK);
+			final String[] range = StrUtil.splitToArray(ipRange, IP_SPLIT_MARK);
 			return list(range[0], range[1]);
 		} else if (ipRange.contains(IP_MASK_SPLIT_MARK)) {
 			// X.X.X.X/X
-			final String[] param = StrUtil.split(ipRange, IP_MASK_SPLIT_MARK);
+			final String[] param = StrUtil.splitToArray(ipRange, IP_MASK_SPLIT_MARK);
 			return list(param[0], Integer.parseInt(param[1]), isAll);
 		} else {
 			return ListUtil.toList(ipRange);
@@ -315,16 +315,5 @@ public class Ipv4Util {
 		return getBeginIpLong(ip, maskBit)
 				+ ~ipv4ToLong(getMaskByMaskBit(maskBit));
 	}
-
-	private static StringBuffer toBin(int x) {
-		StringBuffer result = new StringBuffer();
-		result.append(x % 2);
-		x /= 2;
-		while (x > 0) {
-			result.append(x % 2);
-			x /= 2;
-		}
-		return result;
-	}
 	//-------------------------------------------------------------------------------- Private method end
 }
diff --git a/hutool-core/src/main/java/cn/hutool/core/text/CharSequenceUtil.java b/hutool-core/src/main/java/cn/hutool/core/text/CharSequenceUtil.java
index 5a11ed922..1b5fe8cda 100644
--- a/hutool-core/src/main/java/cn/hutool/core/text/CharSequenceUtil.java
+++ b/hutool-core/src/main/java/cn/hutool/core/text/CharSequenceUtil.java
@@ -49,12 +49,6 @@ public class CharSequenceUtil {
 	 */
 	public static final String SPACE = " ";
 
-	/**
-	 * <p>The maximum size to which the padding constant(s) can expand.</p>
-	 * <p>填充常量可以最大填充的数量</p>
-	 */
-	private static final int PAD_LIMIT = 8192;
-
 	/**
 	 * <p>字符串是否为空白，空白的定义如下：</p>
 	 * <ol>
@@ -2325,7 +2319,7 @@ public class CharSequenceUtil {
 		}
 
 		final List<String> result = new LinkedList<>();
-		final String[] split = split(str, prefix);
+		final String[] split = splitToArray(str, prefix);
 		if (prefix.equals(suffix)) {
 			// 前后缀字符相同，单独处理
 			for (int i = 1, length = split.length - 1; i < length; i += 2) {