Run tool tasks from one entry point

- Create scanner which scans for existing tasks
- Unify options management (mostly because multiple Scanner's are a bad idea)

src/tools/ToolsRunner.java

@@ -0,0 +1,136 @@
+import utils.ScannerHelper;
+import utils.TaskOption;
+import utils.ToolTask;
+import utils.ToolsConstants;
+
+import java.io.File;
+import java.lang.reflect.Constructor;
+import java.lang.reflect.InvocationTargetException;
+import java.lang.reflect.Modifier;
+import java.util.HashMap;
+import java.util.Map;
+import java.util.Scanner;
+
+/**
+ * Main entry point for tool tasks.
+ */
+public class ToolsRunner {
+
+    private static final String DIR_SEPARATOR = File.separator;
+
+    public static void main(String... args) {
+        // Collect tasks and show them
+        File toolsFolder = new File(ToolsConstants.TOOLS_SOURCE_ROOT);
+        Map<String, ToolTask> tasks = new HashMap<>();
+        collectTasksInDirectory(toolsFolder, tasks);
+        showHelp(tasks);
+
+        // Prompt user for task and handle input
+        System.out.println("Please enter the task to run:");
+        Scanner scanner = new Scanner(System.in);
+        String inputTask = scanner.nextLine();
+        ToolTask task = tasks.get(inputTask);
+
+        if (task != null) {
+            executeTask(task, scanner);
+        } else {
+            System.out.println("Unknown task");
+        }
+        scanner.close();
+    }
+
+    /**
+     * Execute the given tool task after prompting the user for the required options.
+     *
+     * @param task The task to run
+     * @param scanner The scanner instance
+     */
+    private static void executeTask(ToolTask task, Scanner scanner) {
+        Iterable<TaskOption> options = task.getOptions();
+        Map<String, String> inputOptions = new HashMap<>();
+        for (TaskOption option : options) {
+            System.out.println(option.getDescription());
+            String input = ScannerHelper.getAnswer(option.getDefaultOption(), scanner, option.getOptions());
+            inputOptions.put(option.getName(), input);
+        }
+
+        task.execute(inputOptions);
+    }
+
+    private static void showHelp(Map<String, ToolTask> taskCollection) {
+        System.out.println("The following tasks are available:");
+        for (String key : taskCollection.keySet()) {
+            System.out.println("- " + key);
+        }
+    }
+
+    // Note ljacqu 20151212: If the tools folder becomes a lot bigger, it will make sense to restrict the depth
+    // of this recursive collector
+    private static void collectTasksInDirectory(File dir, Map<String, ToolTask> taskCollection) {
+        File[] files = dir.listFiles();
+        if (files == null) {
+            throw new RuntimeException("Cannot read folder '" + dir + "'");
+        }
+        for (File file : files) {
+            if (file.isDirectory()) {
+                collectTasksInDirectory(file, taskCollection);
+            } else if (file.isFile()) {
+                ToolTask task = getTaskFromFile(file);
+                if (task != null) {
+                    taskCollection.put(task.getTaskName(), task);
+                }
+            }
+        }
+    }
+
+    /**
+     * Return a {@link ToolTask} instance from the given file.
+     *
+     * @param file The file to load
+     * @return ToolTask instance or null if not applicable
+     */
+    private static ToolTask getTaskFromFile(File file) {
+        Class<? extends ToolTask> taskClass = loadTaskClassFromFile(file);
+        if (taskClass == null) {
+            return null;
+        }
+
+        try {
+            Constructor<? extends ToolTask> constructor = taskClass.getConstructor();
+            return constructor.newInstance();
+        } catch (NoSuchMethodException | InvocationTargetException |
+                 IllegalAccessException | InstantiationException e) {
+            throw new RuntimeException("Cannot instantiate task '" + taskClass + "'");
+        }
+    }
+
+    /**
+     * Return the class the file defines if it implements a {@link ToolTask}.
+     *
+     * @return The class instance, or null if not applicable
+     */
+    @SuppressWarnings("unchecked")
+    private static Class<? extends ToolTask> loadTaskClassFromFile(File file) {
+        if (!file.getName().endsWith(".java")) {
+            return null;
+        }
+
+        String filePath = file.getPath();
+        String className = filePath
+            .substring(ToolsConstants.TOOLS_SOURCE_ROOT.length(), filePath.length() - 5)
+            .replace(DIR_SEPARATOR, ".");
+        try {
+            Class<?> clazz = ClassLoader.getSystemClassLoader().loadClass(className);
+            return ToolTask.class.isAssignableFrom(clazz) && isInstantiable(clazz)
+                ? (Class<? extends ToolTask>) clazz
+                : null;
+        } catch (ClassNotFoundException e) {
+            throw new RuntimeException(e);
+        }
+    }
+
+    private static boolean isInstantiable(Class<?> clazz) {
+        return !clazz.isInterface() && !Modifier.isAbstract(clazz.getModifiers());
+    }
+
+}

src/tools/messages/VerifyMessagesTask.java

@@ -2,10 +2,13 @@ package messages;
 
 import fr.xephi.authme.util.StringUtils;
 import utils.FileUtils;
+import utils.TaskOption;
+import utils.ToolTask;
 import utils.ToolsConstants;
 
 import java.io.File;
 import java.util.ArrayList;
+import java.util.Arrays;
 import java.util.Collections;
 import java.util.HashMap;
 import java.util.List;
@@ -17,27 +20,23 @@ import java.util.regex.Pattern;
 import static java.lang.String.format;
 
 /**
- * Entry point of the messages verifier.
+ * Task to verify the keys in the messages files.
  */
-public final class MessagesVerifierRunner {
+public final class VerifyMessagesTask implements ToolTask {
 
     private static final String MESSAGES_FOLDER = ToolsConstants.MAIN_RESOURCES_ROOT + "messages/";
+    private static final Pattern MESSAGE_FILE_PATTERN = Pattern.compile("messages_[a-z]{2,7}\\.yml");
     private static final String SOURCES_TAG = "{msgdir}";
 
-    private MessagesVerifierRunner() {
+    @Override
+    public String getTaskName() {
+        return "verifyMessages";
     }
 
-    public static void main(String[] args) {
-        // Prompt user for options
-        Scanner scanner = new Scanner(System.in);
-        System.out.println("Check a specific file only?");
-        System.out.println("- Empty line will check all files in the resources messages folder (default)");
-        System.out.println(format("- %s will be replaced to the messages folder %s", SOURCES_TAG, MESSAGES_FOLDER));
-        String inputFile = scanner.nextLine();
-
-        System.out.println("Add any missing keys to files? ['y' = yes]");
-        boolean addMissingKeys = "y".equals(scanner.nextLine());
-        scanner.close();
+    @Override
+    public void execute(Map<String, String> options) {
+        String inputFile = options.get("custom.file");
+        boolean addMissingKeys = options.get("add.missing.keys").equals("y");
 
         // Set up needed objects
         Map<String, String> defaultMessages = null;
@@ -69,6 +68,18 @@ public final class MessagesVerifierRunner {
         }
     }
 
+    @Override
+    public Iterable<TaskOption> getOptions() {
+        String customFileDescription = StringUtils.join(System.getProperty("line.separator"),
+            "Check a specific file only? (optional - enter custom filename)",
+            "- Empty line will check all files in the resources messages folder",
+            format("- %s will be replaced to the messages folder %s", SOURCES_TAG, MESSAGES_FOLDER));
+
+        return Arrays.asList(
+            new TaskOption("custom.file", customFileDescription, "", null),
+            new TaskOption("add.missing.keys", "Add missing keys to files? [y/n]", "n", "y", "n"));
+    }
+
     private static void verifyFile(MessageFileVerifier verifier) {
         Map<String, Boolean> missingKeys = verifier.getMissingKeys();
         if (!missingKeys.isEmpty()) {
@@ -132,7 +143,6 @@ public final class MessagesVerifierRunner {
     }
 
     private static List<File> getMessagesFiles() {
-        final Pattern messageFilePattern = Pattern.compile("messages_[a-z]{2,7}\\.yml");
         File folder = new File(MESSAGES_FOLDER);
         File[] files = folder.listFiles();
         if (files == null) {
@@ -141,7 +151,7 @@ public final class MessagesVerifierRunner {
 
         List<File> messageFiles = new ArrayList<>();
         for (File file : files) {
-            if (messageFilePattern.matcher(file.getName()).matches()) {
+            if (MESSAGE_FILE_PATTERN.matcher(file.getName()).matches()) {
                 messageFiles.add(file);
             }
         }

src/tools/permissions/PermissionsListWriter.java

@@ -3,32 +3,32 @@ package permissions;
 import utils.ANewMap;
 import utils.FileUtils;
 import utils.TagReplacer;
+import utils.TaskOption;
+import utils.ToolTask;
 import utils.ToolsConstants;
 
+import java.util.Arrays;
 import java.util.Map;
-import java.util.Scanner;
 import java.util.Set;
 
 /**
- * Class responsible for formatting a permissions node list and
+ * Task responsible for formatting a permissions node list and
  * for writing it to a file if desired.
  */
-public class PermissionsListWriter {
+public class PermissionsListWriter implements ToolTask {
 
     private static final String PERMISSIONS_OUTPUT_FILE = ToolsConstants.DOCS_FOLDER + "permission_nodes.md";
 
-    public static void main(String[] args) {
-        // Ask if result should be written to file
-        Scanner scanner = new Scanner(System.in);
-        System.out.println("Include description? [Enter 'n' for no]");
-        boolean includeDescription = !matches("n", scanner);
+    @Override
+    public String getTaskName() {
+        return "writePermissionsList";
+    }
 
-        boolean writeToFile = false;
-        if (includeDescription) {
-            System.out.println("Write to file? [Enter 'y' for yes]");
-            writeToFile = matches("y", scanner);
-        }
-        scanner.close();
+    @Override
+    public void execute(Map<String, String> options) {
+        // Ask if result should be written to file
+        boolean includeDescription = options.get("include.description").equals("y");
+        boolean writeToFile = options.get("write.to.file").equals("y");
 
         if (!includeDescription) {
             outputSimpleList();
@@ -39,6 +39,12 @@ public class PermissionsListWriter {
         }
     }
 
+    @Override
+    public Iterable<TaskOption> getOptions() {
+        return Arrays.asList(
+            new TaskOption("include.description", "Include description? [y/n]", "y", "y", "n"),
+            new TaskOption("write.to.file", "Write to file? [y/n]", "n", "y", "n"));
+    }
 
     private static void generateAndWriteFile() {
         final String permissionsTagValue = generatePermissionsList();
@@ -77,9 +83,4 @@ public class PermissionsListWriter {
         System.out.println("Total: " + nodes.size());
     }
 
-    private static boolean matches(String answer, Scanner sc) {
-        String userInput = sc.nextLine();
-        return answer.equalsIgnoreCase(userInput);
-    }
-
 }

src/tools/utils/ScannerHelper.java

@@ -0,0 +1,33 @@
+package utils;
+
+import fr.xephi.authme.util.StringUtils;
+
+import java.util.Scanner;
+
+/**
+ * Helper class for retrieving an answer from a Scanner.
+ */
+public class ScannerHelper {
+
+    // def may be null to force the selection of one of the options
+    // options may be null to just select whatever comes in
+    public static String getAnswer(String def, Scanner scanner, String... options) {
+        while (true) {
+            String input = scanner.nextLine();
+            if (StringUtils.isEmpty(input) && def != null) {
+                return def;
+            }
+
+            if (options == null) {
+                return input;
+            } else {
+                for (String option : options) {
+                    if (input.equals(option)) {
+                        return option;
+                    }
+                }
+            }
+            System.out.println("Invalid answer, please try again");
+        }
+    }
+}

src/tools/utils/TaskOption.java

@@ -0,0 +1,35 @@
+package utils;
+
+/**
+ * Option required by a tool task.
+ */
+public class TaskOption {
+
+    private final String name;
+    private final String description;
+    private final String defaultOption;
+    private final String[] options;
+
+    public TaskOption(String name, String description, String defaultOption, String... options) {
+        this.name = name;
+        this.description = description;
+        this.defaultOption = defaultOption;
+        this.options = options;
+    }
+
+    public String getName() {
+        return name;
+    }
+
+    public String getDescription() {
+        return description;
+    }
+
+    public String getDefaultOption() {
+        return defaultOption;
+    }
+
+    public String[] getOptions() {
+        return options;
+    }
+}

src/tools/utils/ToolTask.java

@@ -0,0 +1,17 @@
+package utils;
+
+import java.util.Map;
+
+/**
+ * Common interface for tool tasks. Note that the implementing tasks are instantiated
+ * with the default constructor. It is required that it be public.
+ */
+public interface ToolTask {
+
+    void execute(Map<String, String> options);
+
+    String getTaskName();
+
+    Iterable<TaskOption> getOptions();
+
+}