Merge pull request #5100 from den314/master

BAEL-2144 Sorting a String alphabetically

java-strings/src/main/java/com/baeldung/string/sorting/AnagramValidator.java

@@ -0,0 +1,29 @@
+package com.baeldung.string.sorting;
+
+import java.util.Arrays;
+
+public class AnagramValidator {
+
+    public static boolean isValid(String text, String anagram) {
+        text = prepare(text);
+        anagram = prepare(anagram);
+
+        String sortedText = sort(text);
+        String sortedAnagram = sort(anagram);
+
+        return sortedText.equals(sortedAnagram);
+    }
+
+    private static String sort(String text) {
+        char[] chars = prepare(text).toCharArray();
+
+        Arrays.sort(chars);
+        return new String(chars);
+    }
+
+    private static String prepare(String text) {
+        return text.toLowerCase()
+            .trim()
+            .replaceAll("\\s+", "");
+    }
+}

java-strings/src/test/java/com/baeldung/string/sorting/AnagramValidatorUnitTest.java

@@ -0,0 +1,26 @@
+package com.baeldung.string.sorting;
+
+
+import static org.junit.jupiter.api.Assertions.assertTrue;
+import static org.junit.jupiter.api.Assertions.assertFalse;
+
+import org.junit.jupiter.api.Test;
+
+import com.baeldung.string.sorting.AnagramValidator;
+
+class AnagramValidatorUnitTest {
+    
+    @Test
+    void givenValidAnagrams_whenSorted_thenEqual() {
+        boolean isValidAnagram = AnagramValidator.isValid("Avida Dollars", "Salvador Dali");
+        
+        assertTrue(isValidAnagram);
+    }
+    
+    @Test
+    void givenNotValidAnagrams_whenSorted_thenNotEqual() {
+        boolean isValidAnagram = AnagramValidator.isValid("abc", "def");
+        
+        assertFalse(isValidAnagram);
+    }
+}

java-strings/src/test/java/com/baeldung/string/sorting/SortStringUnitTest.java

@@ -0,0 +1,31 @@
+package com.baeldung.string.sorting;
+
+import java.util.Arrays;
+
+import org.junit.jupiter.api.Test;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+class SortStringUnitTest {
+
+    @Test
+    void givenString_whenSort_thenSorted() {
+        String abcd = "bdca";
+        char[] chars = abcd.toCharArray();
+
+        Arrays.sort(chars);
+        String sorted = new String(chars);
+
+        assertThat(sorted).isEqualTo("abcd");
+    }
+
+    @Test
+    void givenString_whenSortJava8_thenSorted() {
+        String sorted = "bdca".chars()
+            .sorted()
+            .collect(StringBuilder::new, StringBuilder::appendCodePoint, StringBuilder::append)
+            .toString();
+
+        assertThat(sorted).isEqualTo("abcd");
+    }
+}