[BAEL-5554] Find files that match a wildcard string in Java by @opokharel (#12190)

* BAEL-5554 by @opokharel

* deletedToMoveToSrcFolder

* movedToSrcFolder

* redoingForJenkins

* newPR for [BAEL-5554] Find files that match a wildcard string in Java by @opokharel

* @opokharel

* [BAEL-5554] @opokharel

* [BAEL-5554] Find files that match a wildcard string in Java by @opokharel

* Update SearchFileByWildcardTest.java

* Update SearchFileByWildcard.java

* Update SearchFileByWildcard.java

* Create SearchFileByWildcardUnitTest.java

* Delete SearchFileByWildcardTest.java

* [BAEL-5554] Find files that match a wildcard string in Java by @opokharel

* Update SearchFileByWildcardUnitTest.java

* Update SearchFileByWildcardUnitTest.java

* [BAEL-5554] UnitTestFiles by @opokharel

* Update core-java-modules/core-java-nio-2/src/test/java/com/baeldung/searchfilesbywildcards/SearchFileByWildcardUnitTest.java

Co-authored-by: KevinGilmore <kpg102@gmail.com>

* updated curly braces and assertions

Co-authored-by: KevinGilmore <kpg102@gmail.com>

core-java-modules/core-java-nio-2/src/main/java/com/baeldung/searchfilesbywildcards/SearchFileByWildcard.java

@@ -0,0 +1,37 @@
+package com.baeldung.searchfilesbywildcards;
+
+import java.io.IOException;
+
+import java.nio.file.FileSystem;
+import java.nio.file.FileSystems;
+import java.nio.file.FileVisitResult;
+import java.nio.file.FileVisitor;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.nio.file.PathMatcher;
+import java.nio.file.SimpleFileVisitor;
+import java.nio.file.attribute.BasicFileAttributes;
+
+import java.util.ArrayList;
+import java.util.List;
+
+public class SearchFileByWildcard {
+    public static List<String> matchesList = new ArrayList<String>();
+    public List<String> searchWithWc(Path rootDir, String pattern) throws IOException {
+        matchesList.clear();
+        FileVisitor<Path> matcherVisitor = new SimpleFileVisitor<Path>() {
+            @Override
+            public FileVisitResult visitFile(Path file, BasicFileAttributes attribs) throws IOException {
+                FileSystem fs = FileSystems.getDefault();
+                PathMatcher matcher = fs.getPathMatcher(pattern);
+                Path name = file.getFileName();
+                if (matcher.matches(name)) {
+                    matchesList.add(name.toString());
+                }
+                return FileVisitResult.CONTINUE;
+            }
+        };
+        Files.walkFileTree(rootDir, matcherVisitor);
+        return matchesList;
+    }
+}

core-java-modules/core-java-nio-2/src/test/java/com/baeldung/searchfilesbywildcards/SearchFileByWildcardUnitTest.java

@@ -0,0 +1,30 @@
+package com.baeldung.searchfilesbywildcards;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+import java.io.IOException;
+
+import java.nio.file.Paths;
+
+import java.util.Arrays;
+import java.util.HashSet;
+import java.util.List;
+
+import org.junit.jupiter.api.Test;
+
+public class SearchFileByWildcardUnitTest {
+    @Test
+    public void whenFourFilenameMatch_thenListOfFour() throws IOException {
+        SearchFileByWildcard sfbw = new SearchFileByWildcard();
+        List<String> actual = sfbw.searchWithWc(Paths.get("src/test/resources/sfbw"), "glob:*.{txt,docx}");
+        
+        assertEquals(new HashSet<>(Arrays.asList("six.txt", "three.txt", "two.docx", "one.txt")), new HashSet<>(actual));
+    }
+    @Test
+    public void whenOneFilenameMatch_thenListOfOne() throws IOException {
+        SearchFileByWildcard sfbw = new SearchFileByWildcard();
+        List<String> actual = sfbw.searchWithWc(Paths.get("src/test/resources/sfbw"), "glob:????.{csv}");
+        
+        assertEquals(new HashSet<>(Arrays.asList("five.csv")), new HashSet<>(actual));
+    }
+}