Add list files recursively snippet

iluwatar · iluwatar · commit 91f411e9a64e · 2017-12-21T16:32:18.000+02:00
diff --git a/README.md b/README.md
@@ -16,6 +16,7 @@ Update the sample application with the snippet and add a test for it. After prov
 ### File
 * [List directories](#list-directories)
 * [List files in directory](#list-files-in-directory)
+* [List files in directory recursively](#list-files-in-directory-recursively)
 * [Read lines from file to string list](#read-lines-from-file-to-string-list)
 
 ### Math
@@ -86,6 +87,27 @@ Update the sample application with the snippet and add a test for it. After prov
 
 [⬆ back to top](#table-of-contents)
 
+### List files in directory recursively
+
+```java
+    public static List<File> listAllFiles(String path) {
+        List<File> all = new ArrayList<>();
+        File[] list = new File(path).listFiles();
+        if (list != null) {  // In case of access error, list is null
+            for (File f : list) {
+                if (f.isDirectory()) {
+                    all.addAll(listAllFiles(f.getAbsolutePath()));
+                } else {
+                    all.add(f.getAbsoluteFile());
+                }
+            }
+        }
+        return all;
+    }
+```
+
+[⬆ back to top](#table-of-contents)
+
 ### Read lines from file to string list
 
 ```java
diff --git a/src/main/java/Library.java b/src/main/java/Library.java
@@ -159,4 +159,24 @@ public static boolean isPalindrome(String s) {
     public static File[] listFilesInDirectory(final File folder) {
         return folder.listFiles(File::isFile);
     }
+
+    /**
+     * Recursively list all the files in directory
+     * @param path the path to start the search from
+     * @return list of all files
+     */
+    public static List<File> listAllFiles(String path) {
+        List<File> all = new ArrayList<>();
+        File[] list = new File(path).listFiles();
+        if (list != null) {  // In case of access error, list is null
+            for (File f : list) {
+                if (f.isDirectory()) {
+                    all.addAll(listAllFiles(f.getAbsolutePath()));
+                } else {
+                    all.add(f.getAbsoluteFile());
+                }
+            }
+        }
+        return all;
+    }
 }
diff --git a/src/test/java/LibraryTest.java b/src/test/java/LibraryTest.java
@@ -172,4 +172,13 @@ public void testListFilesInDirectory() {
         assertEquals(1, files.length);
         assertEquals("src/test/resources/somelines.txt", files[0].toString());
     }
+
+    /**
+     * Tests for {@link Library#listAllFiles(String)}
+     */
+    @Test
+    public void testListAllFiles() {
+        List<File> files = Library.listAllFiles("src/test/resources");
+        assertEquals(3, files.size());
+    }
 }

Original file line number	Diff line number	Diff line change
`@@ -172,4 +172,13 @@ public void testListFilesInDirectory() {`
`172`	`172`	`assertEquals(1, files.length);`
`173`	`173`	`assertEquals("src/test/resources/somelines.txt", files[0].toString());`
`174`	`174`	`}`
	`175`	`+`
	`176`	`+ /**`
	`177`	`+ * Tests for {@link Library#listAllFiles(String)}`
	`178`	`+ */`
	`179`	`+ @Test`
	`180`	`+ public void testListAllFiles() {`
	`181`	`+ List<File> files = Library.listAllFiles("src/test/resources");`
	`182`	`+ assertEquals(3, files.size());`
	`183`	`+ }`
`175`	`184`	`}`