diff --git a/hutool-core/src/main/java/cn/hutool/core/convert/NumberWordFormater.java b/hutool-core/src/main/java/cn/hutool/core/convert/NumberWordFormater.java
index 2b3368614..69af19156 100644
--- a/hutool-core/src/main/java/cn/hutool/core/convert/NumberWordFormater.java
+++ b/hutool-core/src/main/java/cn/hutool/core/convert/NumberWordFormater.java
@@ -2,6 +2,8 @@ package cn.hutool.core.convert;
 
 import cn.hutool.core.util.StrUtil;
 
+import java.util.Objects;
+
 /**
  * 将浮点数类型的number转换成英语的表达方式 <br>
  * 参考博客：http://blog.csdn.net/eric_sunah/article/details/8713226
@@ -68,7 +70,7 @@ public class NumberWordFormater {
 		StringBuilder lm = new StringBuilder(); // 用来存放转换後的整数部分
 		for (int i = 0; i < lstrrev.length() / 3; i++) {
 			a[i] = StrUtil.reverse(lstrrev.substring(3 * i, 3 * i + 3)); // 截取第一个叁位
-			if (!a[i].equals("000")) { // 用来避免这种情况：1000000 = one million
+			if (!Objects.equals(a[i],"000")) { // 用来避免这种情况：1000000 = one million
 										// thousand only
 				if (i != 0) {
 					lm.insert(0, transThree(a[i]) + " " + parseMore(i) + " "); // 加:
@@ -134,7 +136,7 @@ public class NumberWordFormater {
 		String value;
 		if (s.startsWith("0")) {// 是否小於100
 			value = transTwo(s.substring(1));
-		} else if (s.substring(1).equals("00")) {// 是否被100整除
+		} else if (Objects.equals(s.substring(1),"00")) {// 是否被100整除
 			value = parseFirst(s.substring(0, 1)) + " HUNDRED";
 		} else {
 			value = parseFirst(s.substring(0, 1)) + " HUNDRED AND " + transTwo(s.substring(1));
diff --git a/hutool-core/src/main/java/cn/hutool/core/date/format/FastDateParser.java b/hutool-core/src/main/java/cn/hutool/core/date/format/FastDateParser.java
index c50630bee..eab2a55bd 100644
--- a/hutool-core/src/main/java/cn/hutool/core/date/format/FastDateParser.java
+++ b/hutool-core/src/main/java/cn/hutool/core/date/format/FastDateParser.java
@@ -5,18 +5,7 @@ import java.io.ObjectInputStream;
 import java.text.DateFormatSymbols;
 import java.text.ParseException;
 import java.text.ParsePosition;
-import java.util.ArrayList;
-import java.util.Calendar;
-import java.util.Comparator;
-import java.util.Date;
-import java.util.HashMap;
-import java.util.List;
-import java.util.ListIterator;
-import java.util.Locale;
-import java.util.Map;
-import java.util.Set;
-import java.util.TimeZone;
-import java.util.TreeSet;
+import java.util.*;
 import java.util.concurrent.ConcurrentHashMap;
 import java.util.concurrent.ConcurrentMap;
 import java.util.regex.Matcher;
@@ -688,7 +677,7 @@ class FastDateParser extends AbstractDateBasic implements DateParser {
 			for (final String[] zoneNames : zones) {
 				// offset 0 is the time zone ID and is not localized
 				final String tzId = zoneNames[ID];
-				if (tzId.equalsIgnoreCase("GMT")) {
+				if ("GMT".equalsIgnoreCase(tzId)) {
 					continue;
 				}
 				final TimeZone tz = TimeZone.getTimeZone(tzId);
@@ -761,7 +750,7 @@ class FastDateParser extends AbstractDateBasic implements DateParser {
 		 */
 		@Override
 		void setCalendar(final FastDateParser parser, final Calendar cal, final String value) {
-			if (value.equals("Z")) {
+			if (Objects.equals(value,"Z")) {
 				cal.setTimeZone(TimeZone.getTimeZone("UTC"));
 			} else {
 				cal.setTimeZone(TimeZone.getTimeZone("GMT" + value));
diff --git a/hutool-core/src/main/java/cn/hutool/core/util/IdcardUtil.java b/hutool-core/src/main/java/cn/hutool/core/util/IdcardUtil.java
index 71694ffe5..f88984e0f 100644
--- a/hutool-core/src/main/java/cn/hutool/core/util/IdcardUtil.java
+++ b/hutool-core/src/main/java/cn/hutool/core/util/IdcardUtil.java
@@ -175,7 +175,7 @@ public class IdcardUtil {
 				return isValidCard15(idCard);
 			case 10: {// 10位身份证，港澳台地区
 				String[] cardval = isValidCard10(idCard);
-				return null != cardval && cardval[2].equals("true");
+				return null != cardval && Objects.equals(cardval[2],"true");
 			}
 			default:
 				return false;
@@ -280,9 +280,9 @@ public class IdcardUtil {
 		if (idCard.matches("^[a-zA-Z][0-9]{9}$")) { // 台湾
 			info[0] = "台湾";
 			String char2 = idCard.substring(1, 2);
-			if (char2.equals("1")) {
+			if (Objects.equals(char2,"1")) {
 				info[1] = "M";
-			} else if (char2.equals("2")) {
+			} else if (Objects.equals(char2,"2")) {
 				info[1] = "F";
 			} else {
 				info[1] = "N";
diff --git a/hutool-core/src/main/java/cn/hutool/core/util/ReflectUtil.java b/hutool-core/src/main/java/cn/hutool/core/util/ReflectUtil.java
index 2391d4ecb..d47fe3a0d 100644
--- a/hutool-core/src/main/java/cn/hutool/core/util/ReflectUtil.java
+++ b/hutool-core/src/main/java/cn/hutool/core/util/ReflectUtil.java
@@ -12,12 +12,7 @@ import java.lang.reflect.AccessibleObject;
 import java.lang.reflect.Constructor;
 import java.lang.reflect.Field;
 import java.lang.reflect.Method;
-import java.util.ArrayList;
-import java.util.HashMap;
-import java.util.HashSet;
-import java.util.List;
-import java.util.Map;
-import java.util.Set;
+import java.util.*;
 
 /**
  * 反射工具类
@@ -652,7 +647,7 @@ public class ReflectUtil {
 	 * @return 是否为equals方法
 	 */
 	public static boolean isEqualsMethod(Method method) {
-		if (method == null || false == method.getName().equals("equals")) {
+		if (method == null || false == Objects.equals(method.getName(),"equals")) {
 			return false;
 		}
 		final Class<?>[] paramTypes = method.getParameterTypes();
@@ -666,7 +661,7 @@ public class ReflectUtil {
 	 * @return 是否为hashCode方法
 	 */
 	public static boolean isHashCodeMethod(Method method) {
-		return (method != null && method.getName().equals("hashCode") && method.getParameterTypes().length == 0);
+		return (method != null && Objects.equals(method.getName(),"hashCode") && method.getParameterTypes().length == 0);
 	}
 
 	/**
@@ -676,7 +671,7 @@ public class ReflectUtil {
 	 * @return 是否为toString方法
 	 */
 	public static boolean isToStringMethod(Method method) {
-		return (method != null && method.getName().equals("toString") && method.getParameterTypes().length == 0);
+		return (method != null && Objects.equals(method.getName(),"toString") && method.getParameterTypes().length == 0);
 	}
 
 	// --------------------------------------------------------------------------------------------------------- newInstance
diff --git a/hutool-cron/src/main/java/cn/hutool/cron/pattern/parser/DayOfMonthValueParser.java b/hutool-cron/src/main/java/cn/hutool/cron/pattern/parser/DayOfMonthValueParser.java
index 29edcf667..8c12dd1e1 100644
--- a/hutool-cron/src/main/java/cn/hutool/cron/pattern/parser/DayOfMonthValueParser.java
+++ b/hutool-cron/src/main/java/cn/hutool/cron/pattern/parser/DayOfMonthValueParser.java
@@ -2,6 +2,8 @@ package cn.hutool.cron.pattern.parser;
 
 import cn.hutool.cron.CronException;
 
+import java.util.Objects;
+
 /**
  * 每月的几号值处理<br>
  * 每月最多31天，32和“L”都表示最后一天
@@ -17,7 +19,7 @@ public class DayOfMonthValueParser extends SimpleValueParser {
 
 	@Override
 	public int parse(String value) throws CronException {
-		if (value.equalsIgnoreCase("L") || value.equals("32")) {// 每月最后一天
+		if ("L".equalsIgnoreCase(value) || Objects.equals("32",value)) {// 每月最后一天
 			return 32;
 		} else {
 			return super.parse(value);
diff --git a/hutool-cron/src/main/java/cn/hutool/cron/pattern/parser/DayOfWeekValueParser.java b/hutool-cron/src/main/java/cn/hutool/cron/pattern/parser/DayOfWeekValueParser.java
index aebc27087..db2c8fdc4 100644
--- a/hutool-cron/src/main/java/cn/hutool/cron/pattern/parser/DayOfWeekValueParser.java
+++ b/hutool-cron/src/main/java/cn/hutool/cron/pattern/parser/DayOfWeekValueParser.java
@@ -38,7 +38,7 @@ public class DayOfWeekValueParser extends SimpleValueParser {
 	 * @throws CronException 无效别名抛出此异常
 	 */
 	private int parseAlias(String value) throws CronException {
-		if(value.equalsIgnoreCase("L")){
+		if("L".equalsIgnoreCase(value)){
 			//最后一天为星期六
 			return ALIASES.length - 1;
 		}
diff --git a/hutool-db/src/main/java/cn/hutool/db/sql/SqlFormatter.java b/hutool-db/src/main/java/cn/hutool/db/sql/SqlFormatter.java
index 69fe04607..c518336c2 100644
--- a/hutool-db/src/main/java/cn/hutool/db/sql/SqlFormatter.java
+++ b/hutool-db/src/main/java/cn/hutool/db/sql/SqlFormatter.java
@@ -1,9 +1,6 @@
 package cn.hutool.db.sql;
 
-import java.util.HashSet;
-import java.util.LinkedList;
-import java.util.Set;
-import java.util.StringTokenizer;
+import java.util.*;
 
 /**
  * SQL格式化器 from Hibernate
@@ -129,7 +126,7 @@ public class SqlFormatter {
 					values();
 				} else if ("on".equals(this.lcToken)) {
 					on();
-				} else if ((this.afterBetween) && (this.lcToken.equals("and"))) {
+				} else if ((this.afterBetween) && (Objects.equals(this.lcToken,"and"))) {
 					misc();
 					this.afterBetween = false;
 				} else if (LOGICAL.contains(this.lcToken)) {
diff --git a/hutool-extra/src/main/java/cn/hutool/extra/ftp/Ftp.java b/hutool-extra/src/main/java/cn/hutool/extra/ftp/Ftp.java
index 12afd4dff..0584f7276 100644
--- a/hutool-extra/src/main/java/cn/hutool/extra/ftp/Ftp.java
+++ b/hutool-extra/src/main/java/cn/hutool/extra/ftp/Ftp.java
@@ -7,6 +7,7 @@ import java.io.OutputStream;
 import java.nio.charset.Charset;
 import java.util.ArrayList;
 import java.util.List;
+import java.util.Objects;
 
 import org.apache.commons.net.ftp.FTPClient;
 import org.apache.commons.net.ftp.FTPFile;
@@ -339,7 +340,7 @@ public class Ftp extends AbstractFtp {
 			childPath = StrUtil.format("{}/{}", dirPath, name);
 			if (ftpFile.isDirectory()) {
 				// 上级和本级目录除外
-				if (false == name.equals(".") && false == name.equals("..")) {
+				if (false == Objects.equals(name,".") && false == Objects.equals(name,"..")) {
 					delDir(childPath);
 				}
 			} else {
diff --git a/hutool-extra/src/main/java/cn/hutool/extra/ssh/Sftp.java b/hutool-extra/src/main/java/cn/hutool/extra/ssh/Sftp.java
index 7565a6892..d6f80887f 100644
--- a/hutool-extra/src/main/java/cn/hutool/extra/ssh/Sftp.java
+++ b/hutool-extra/src/main/java/cn/hutool/extra/ssh/Sftp.java
@@ -15,6 +15,7 @@ import java.io.File;
 import java.nio.charset.Charset;
 import java.util.ArrayList;
 import java.util.List;
+import java.util.Objects;
 import java.util.Vector;
 
 /**
@@ -311,7 +312,7 @@ public class Sftp extends AbstractFtp {
 		String fileName;
 		for (LsEntry entry : list) {
 			fileName = entry.getFilename();
-			if (false == fileName.equals(".") && false == fileName.equals("..")) {
+			if (false == Objects.equals(fileName,".") && false == Objects.equals(fileName,"..")) {
 				if (entry.getAttrs().isDir()) {
 					delDir(fileName);
 				} else {
diff --git a/hutool-http/src/main/java/cn/hutool/http/HttpRequest.java b/hutool-http/src/main/java/cn/hutool/http/HttpRequest.java
index c8c8e003e..bbd7edb87 100644
--- a/hutool-http/src/main/java/cn/hutool/http/HttpRequest.java
+++ b/hutool-http/src/main/java/cn/hutool/http/HttpRequest.java
@@ -381,7 +381,7 @@ public class HttpRequest extends HttpBase<HttpRequest> {
 			return !httpVersion.equalsIgnoreCase(HTTP_1_0);
 		}
 
-		return !connection.equalsIgnoreCase("close");
+		return !"close".equalsIgnoreCase(connection);
 	}
 
 	/**
diff --git a/hutool-http/src/main/java/cn/hutool/http/HttpResponse.java b/hutool-http/src/main/java/cn/hutool/http/HttpResponse.java
index 029eb0940..9dd7210b4 100644
--- a/hutool-http/src/main/java/cn/hutool/http/HttpResponse.java
+++ b/hutool-http/src/main/java/cn/hutool/http/HttpResponse.java
@@ -111,7 +111,7 @@ public class HttpResponse extends HttpBase<HttpResponse> implements Closeable {
 	 */
 	public boolean isGzip() {
 		final String contentEncoding = contentEncoding();
-		return contentEncoding != null && contentEncoding.equalsIgnoreCase("gzip");
+		return contentEncoding != null && "gzip".equalsIgnoreCase(contentEncoding);
 	}
 
 	/**
@@ -122,7 +122,7 @@ public class HttpResponse extends HttpBase<HttpResponse> implements Closeable {
 	 */
 	public boolean isDeflate() {
 		final String contentEncoding = contentEncoding();
-		return contentEncoding != null && contentEncoding.equalsIgnoreCase("deflate");
+		return contentEncoding != null && "deflate".equalsIgnoreCase(contentEncoding);
 	}
 
 	/**
@@ -133,7 +133,7 @@ public class HttpResponse extends HttpBase<HttpResponse> implements Closeable {
 	 */
 	public boolean isChunked() {
 		final String transferEncoding = header(Header.TRANSFER_ENCODING);
-		return transferEncoding != null && transferEncoding.equalsIgnoreCase("Chunked");
+		return transferEncoding != null && "Chunked".equalsIgnoreCase(transferEncoding);
 	}
 
 	/**