Create multiple directories at once

Users don't have to call `createDirectory` for each directory.

Fixes #3.

README.md

@@ -21,7 +21,7 @@ Fake SFTP Server Rule is available from [Maven Central](http://search.maven.org/
     <dependency>
       <groupId>com.github.stefanbirkner</groupId>
       <artifactId>fake-sftp-server-rule</artifactId>
-      <version>1.1.1</version>
+      <version>1.2.0</version>
     </dependency>
 
 
@@ -95,6 +95,17 @@ If you need an empty directory then you can use the method
       //code that reads from or writes to that directory
     }
 
+You may create multiple directories at once with `createDirectories(String...)`.
+
+    @Test
+    public void testDirectories() {
+      sftpServer.createDirectories(
+        "/a/directory",
+        "/another/directory"
+      );
+      //code that reads from or writes to that directories
+    }
+
 
 ### Testing code that writes files
 

pom.xml

@@ -9,7 +9,7 @@
     </parent>
 
     <artifactId>fake-sftp-server-rule</artifactId>
-    <version>1.2.0-SNAPSHOT</version>
+    <version>1.2.0</version>
     <packaging>jar</packaging>
 
     <name>Fake SFTP Server Rule</name>

src/main/java/com/github/stefanbirkner/fakesftpserver/rule/FakeSftpServerRule.java

@@ -89,7 +89,18 @@
  *   //code that reads from or writes to that directory
  * }
  * </pre>
- *
+ * <p>You may create multiple directories at once with
+ * {@link #createDirectories(String...)}.
+ * <pre>
+ * &#064;Test
+ * public void testDirectories() {
+ *   sftpServer.{@link #createDirectories(String...) createDirectories}(
+ *     "/a/directory",
+ *     "/another/directory"
+ *   );
+ *   //code that reads from or writes to that directories
+ * }
+ * </pre>
  * <h2>Testing code that writes files</h2>
  * <p>If you test code that writes files to an SFTP server then you need to
  * verify the upload. Fake SFTP Server Rule provides a shortcut for getting the
@@ -235,7 +246,19 @@ public void createDirectory(
     ) throws IOException {
         verifyThatTestIsRunning("create directory");
         Path pathAsObject = fileSystem.getPath(path);
-        createDirectories(pathAsObject);
+        Files.createDirectories(pathAsObject);
+    }
+
+    /**
+     * Create multiple directories on the SFTP server.
+     * @param paths the directories' paths.
+     * @throws IOException if at least one directory cannot be created.
+     */
+    public void createDirectories(
+        String... paths
+    ) throws IOException {
+        for (String path: paths)
+            createDirectory(path);
     }
 
     /**
@@ -339,7 +362,7 @@ private void ensureDirectoryOfPathExists(
     ) throws IOException {
         Path directory = path.getParent();
         if (directory != null && !directory.equals(path.getRoot()))
-            createDirectories(directory);
+            Files.createDirectories(directory);
     }
 
     private void verifyThatTestIsRunning(

src/test/java/com/github/stefanbirkner/fakesftpserver/rule/FakeSftpServerRuleTest.java

@@ -305,49 +305,110 @@ public void cannot_be_put_after_the_test_is_finished() {
         }
     }
 
+    @RunWith(Enclosed.class)
     public static class directory_creation {
-        @Test
-        public void a_directory_that_is_created_with_the_rule_can_be_read_by_a_client() {
-            FakeSftpServerRule sftpServer = new FakeSftpServerRule();
-            executeTestWithRule(
-                () -> {
-                    sftpServer.createDirectory("/a/directory");
-                    assertEmptyDirectory(sftpServer, "/a/directory");
-                },
-                sftpServer
-            );
-        }
 
-        @Test
-        public void a_directory_cannot_be_created_before_the_test_is_started() {
-            FakeSftpServerRule sftpServer = new FakeSftpServerRule();
-            Throwable exception = exceptionThrownBy(
-                () -> sftpServer.createDirectory("/a/directory")
-            );
-            assertThat(exception)
-                .isInstanceOf(IllegalStateException.class)
-                .hasMessage(
-                    "Failed to create directory because test has not been"
-                        + " started or is already finished."
+        public static class a_single_directory {
+            @Test
+            public void that_is_created_with_the_rule_can_be_read_by_a_client() {
+                FakeSftpServerRule sftpServer = new FakeSftpServerRule();
+                executeTestWithRule(
+                    () -> {
+                        sftpServer.createDirectory("/a/directory");
+                        assertEmptyDirectory(sftpServer, "/a/directory");
+                    },
+                    sftpServer
                 );
+            }
+
+            @Test
+            public void cannot_be_created_before_the_test_is_started() {
+                FakeSftpServerRule sftpServer = new FakeSftpServerRule();
+                Throwable exception = exceptionThrownBy(
+                    () -> sftpServer.createDirectory("/a/directory")
+                );
+                assertThat(exception)
+                    .isInstanceOf(IllegalStateException.class)
+                    .hasMessage(
+                        "Failed to create directory because test has not been"
+                            + " started or is already finished."
+                    );
+            }
+
+            @Test
+            public void cannot_be_created_after_the_test_is_finished() {
+                FakeSftpServerRule sftpServer = new FakeSftpServerRule();
+                executeTestWithRule(
+                    () -> {
+                    },
+                    sftpServer
+                );
+                Throwable exception = exceptionThrownBy(
+                    () -> sftpServer.createDirectory("/a/directory")
+                );
+                assertThat(exception)
+                    .isInstanceOf(IllegalStateException.class)
+                    .hasMessage(
+                        "Failed to create directory because test has not been"
+                            + " started or is already finished."
+                    );
+            }
         }
 
-        @Test
-        public void a_directory_cannot_be_created_after_the_test_is_finished() {
-            FakeSftpServerRule sftpServer = new FakeSftpServerRule();
-            executeTestWithRule(
-                () -> {},
-                sftpServer
-            );
-            Throwable exception = exceptionThrownBy(
-                () -> sftpServer.createDirectory("/a/directory")
-            );
-            assertThat(exception)
-                .isInstanceOf(IllegalStateException.class)
-                .hasMessage(
-                    "Failed to create directory because test has not been"
-                        + " started or is already finished."
+        public static class multiple_directories {
+            @Test
+            public void that_are_created_with_the_rule_can_be_read_by_a_client() {
+                FakeSftpServerRule sftpServer = new FakeSftpServerRule();
+                executeTestWithRule(
+                    () -> {
+                        sftpServer.createDirectories(
+                            "/a/directory",
+                            "/another/directory"
+                        );
+                        assertEmptyDirectory(sftpServer, "/a/directory");
+                        assertEmptyDirectory(sftpServer, "/another/directory");
+                    },
+                    sftpServer
+                );
+            }
+
+            @Test
+            public void cannot_be_created_before_the_test_is_started() {
+                FakeSftpServerRule sftpServer = new FakeSftpServerRule();
+                Throwable exception = exceptionThrownBy(
+                    () -> sftpServer.createDirectories(
+                        "/a/directory",
+                        "/another/directory"
+                    )
                 );
+                assertThat(exception)
+                    .isInstanceOf(IllegalStateException.class)
+                    .hasMessage(
+                        "Failed to create directory because test has not been"
+                            + " started or is already finished."
+                    );
+            }
+
+            @Test
+            public void cannot_be_created_after_the_test_is_finished() {
+                FakeSftpServerRule sftpServer = new FakeSftpServerRule();
+                executeTestWithRule(
+                    () -> {},
+                    sftpServer
+                );
+                Throwable exception = exceptionThrownBy(
+                    () -> sftpServer.createDirectories(
+                        "/a/directory",
+                        "/another/directory"
+                    )
+                );
+                assertThat(exception)
+                    .isInstanceOf(IllegalStateException.class)
+                    .hasMessage(
+                        "Failed to create directory because test has not been"
+                            + " started or is already finished."
+                    );
+            }
         }
 
         private static void assertEmptyDirectory(