修复PasswdStrength.checkindexOf逻辑问题（pr#4114@Github）。

hutool-core/src/main/java/cn/hutool/v7/core/data/PasswdStrength.java

@@ -94,7 +94,7 @@ public class PasswdStrength {
 	 * @return strength level
 	 */
 	public static int check(final String passwd) {
-		if (null == passwd) {
+		if (StrUtil.isEmpty(passwd)) {
 			throw new IllegalArgumentException("password is empty");
 		}
 		final int len = passwd.length();
@@ -175,13 +175,13 @@ public class PasswdStrength {
 		}
 
 		// decrease points
-		if ("abcdefghijklmnopqrstuvwxyz".indexOf(passwd) > 0 || "ABCDEFGHIJKLMNOPQRSTUVWXYZ".indexOf(passwd) > 0) {
+		if ("abcdefghijklmnopqrstuvwxyz".contains(passwd) || "ABCDEFGHIJKLMNOPQRSTUVWXYZ".contains(passwd)) {
 			level--;
 		}
-		if ("qwertyuiop".indexOf(passwd) > 0 || "asdfghjkl".indexOf(passwd) > 0 || "zxcvbnm".indexOf(passwd) > 0) {
+		if ("qwertyuiop".contains(passwd) || "asdfghjkl".contains(passwd) || "zxcvbnm".contains(passwd)) {
 			level--;
 		}
-		if (StrUtil.isNumeric(passwd) && ("01234567890".indexOf(passwd) > 0 || "09876543210".indexOf(passwd) > 0)) {
+		if (StrUtil.isNumeric(passwd) && ("01234567890".contains(passwd) || "09876543210".contains(passwd))) {
 			level--;
 		}
 
@@ -251,39 +251,24 @@ public class PasswdStrength {
 	}
 
 	/**
-	 * Get password strength level, includes easy, midium, strong, very strong, extremely strong
+	 * Get password strength level, includes easy, medium, strong, very strong, extremely strong
 	 *
 	 * @param passwd 密码
 	 * @return 密码等级枚举
 	 */
 	public static PASSWD_LEVEL getLevel(final String passwd) {
 		final int level = check(passwd);
-		switch (level) {
+		return switch (level) {
-			case 0:
+			case 0, 1, 2, 3 -> PASSWD_LEVEL.EASY;
-			case 1:
+			case 4, 5, 6 -> PASSWD_LEVEL.MEDIUM;
-			case 2:
+			case 7, 8, 9 -> PASSWD_LEVEL.STRONG;
-			case 3:
+			case 10, 11, 12 -> PASSWD_LEVEL.VERY_STRONG;
-				return PASSWD_LEVEL.EASY;
+			default -> PASSWD_LEVEL.EXTREMELY_STRONG;
-			case 4:
+		};
-			case 5:
-			case 6:
-				return PASSWD_LEVEL.MEDIUM;
-			case 7:
-			case 8:
-			case 9:
-				return PASSWD_LEVEL.STRONG;
-			case 10:
-			case 11:
-			case 12:
-				return PASSWD_LEVEL.VERY_STRONG;
-			default:
-				return PASSWD_LEVEL.EXTREMELY_STRONG;
-		}
 	}
 
 	/**
-	 * Check character's type, includes num, capital letter, small letter and other character.
+	 * 检查字符类型，包括数字、大写字母、小写字母及其他字符
-	 * 检查字符类型
 	 *
 	 * @param c 字符
 	 * @return 类型

hutool-core/src/test/java/cn/hutool/v7/core/data/PasswdStrengthTest.java

@@ -16,19 +16,60 @@
 
 package cn.hutool.v7.core.data;
 
-import org.junit.jupiter.api.Assertions;
 import org.junit.jupiter.api.Test;
 
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+
 public class PasswdStrengthTest {
 	@Test
 	public void strengthTest(){
 		final String passwd = "2hAj5#mne-ix.86H";
-		Assertions.assertEquals(13, PasswdStrength.check(passwd));
+		assertEquals(13, PasswdStrength.check(passwd));
 	}
 
 	@Test
 	public void strengthNumberTest(){
 		final String passwd = "9999999999999";
-		Assertions.assertEquals(0, PasswdStrength.check(passwd));
+		assertEquals(0, PasswdStrength.check(passwd));
+	}
+
+	@Test
+	void strengthEmptyTest(){
+		final String passwd = null;
+		assertThrows(IllegalArgumentException.class, () -> PasswdStrength.check(passwd));
+
+		final String passwd2 = "";
+		assertThrows(IllegalArgumentException.class, () -> PasswdStrength.check(passwd2));
+	}
+
+	@Test
+	void strengthBlankTest(){
+		String passwd = " ";
+		assertEquals(0, PasswdStrength.check(passwd));
+
+		passwd = "   ";
+		assertEquals(0, PasswdStrength.check(passwd));
+	}
+
+	@Test
+	public void consecutiveLettersTest() {
+		// 测试连续小写字母会被降级
+		assertEquals(0, PasswdStrength.check("abcdefghijklmn"));
+		// 测试连续大写字母会被降级
+		assertEquals(0, PasswdStrength.check("ABCDEFGHIJKLMN"));
+	}
+
+	@Test
+	public void dictionaryWeakPasswordTest() {
+		// 测试包含简单密码字典中的弱密码
+		assertEquals(0, PasswdStrength.check("password"));
+		assertEquals(3, PasswdStrength.check("password2"));
+	}
+
+	@Test
+	public void numericSequenceTest() {
+		assertEquals(0, PasswdStrength.check("01234567890"));
+		assertEquals(0, PasswdStrength.check("09876543210"));
 	}
 }