Add converting framework as well as the converter for Backpack

Adds command /pvconvert <all | plugin name>
Adds permission playervaults.convert
Adds Converter interface for future converters
Adds BackpackConverter - A converter for Backpack
(http://dev.bukkit.org/bukkit-plugins/backpack/)

src/main/java/com/drtshock/playervaults/converters/BackpackConverter.java

@@ -0,0 +1,95 @@
+package com.drtshock.playervaults.converters;
+
+import com.drtshock.playervaults.PlayerVaults;
+import com.drtshock.playervaults.vaultmanagement.UUIDVaultManager;
+import org.bukkit.OfflinePlayer;
+import org.bukkit.configuration.ConfigurationSection;
+import org.bukkit.configuration.file.FileConfiguration;
+import org.bukkit.configuration.file.YamlConfiguration;
+import org.bukkit.inventory.Inventory;
+import org.bukkit.inventory.ItemStack;
+
+import java.io.File;
+import java.io.IOException;
+import java.util.UUID;
+
+/**
+ * Simple converter for Backpack (http://dev.bukkit.org/bukkit-plugins/backpack/)
+ *
+ * @author turt2live
+ */
+public class BackpackConverter implements Converter {
+
+    @Override
+    public int doConvert() {
+        PlayerVaults plugin = PlayerVaults.getInstance();
+        File destination = new File(plugin.getDataFolder().getParentFile(), "Backpack" + File.separator + "backpacks");
+        if (!destination.exists()) return -1;
+
+        int converted = 0;
+
+        File[] worldDirs = destination.listFiles();
+        int vaultNum = 1;
+        for (File file : worldDirs != null ? worldDirs : new File[0]) {
+            if (file.isDirectory()) {
+                converted += convert(file, vaultNum);
+                vaultNum++;
+            }
+        }
+
+        return converted;
+    }
+
+    private int convert(File worldFolder, int intoVaultNum) {
+        PlayerVaults plugin = PlayerVaults.getInstance();
+        UUIDVaultManager vaults = UUIDVaultManager.getInstance();
+        int converted = 0;
+        File[] files = worldFolder.listFiles();
+        for (File file : files != null ? files : new File[0]) {
+            if (file.isFile() && file.getName().toLowerCase().endsWith(".yml")) {
+                OfflinePlayer player = plugin.getServer().getOfflinePlayer(file.getName().substring(0, file.getName().lastIndexOf('.')));
+                if (player == null || player.getUniqueId() == null) {
+                    plugin.getLogger().warning("Unable to convert Backpack for player: " + (player != null ? player.getName() : file.getName()));
+                } else {
+                    UUID uuid = player.getUniqueId();
+                    FileConfiguration yaml = YamlConfiguration.loadConfiguration(file);
+                    ConfigurationSection section = yaml.getConfigurationSection("backpack");
+                    if (section.getKeys(false).size() <= 0) continue; // No slots
+
+                    Inventory vault = vaults.getVault(uuid, intoVaultNum);
+                    if (vault == null) vault = plugin.getServer().createInventory(null, section.getKeys(false).size());
+                    for (String key : section.getKeys(false)) {
+                        ConfigurationSection slotSection = section.getConfigurationSection(key);
+                        ItemStack item = slotSection.getItemStack("ItemStack");
+                        if (item == null) continue;
+
+                        // Overwrite
+                        vault.setItem(Integer.parseInt(key.split(" ")[1]), item);
+                    }
+                    try {
+                        vaults.saveVault(vault, uuid, intoVaultNum);
+                        converted++;
+                    } catch (IOException e) {
+                        plugin.getLogger().severe("Error converting Backpack: " + file.getName());
+                        e.printStackTrace();
+                    }
+                }
+            }
+        }
+        return converted;
+    }
+
+    @Override
+    public boolean canConvert() {
+        PlayerVaults plugin = PlayerVaults.getInstance();
+        File expectedFolder = new File(plugin.getDataFolder().getParentFile(), "Backpack");
+        if (!expectedFolder.exists()) return false;
+        File backpackDir = new File(expectedFolder, "backpacks");
+        return backpackDir.exists();
+    }
+
+    @Override
+    public String getName() {
+        return "Backpack";
+    }
+}

src/main/java/com/drtshock/playervaults/converters/Converter.java

@@ -0,0 +1,34 @@
+package com.drtshock.playervaults.converters;
+
+/**
+ * Represents a simple converter for converting another plugin's content
+ * to PlayerVaults.
+ *
+ * @author turt2live
+ */
+public interface Converter {
+
+    /**
+     * Converts the other plugin's data.
+     *
+     * @return the number of vaults converted. Returns 0 on none converted
+     * or -1 if no vaults were converted.
+     */
+    public int doConvert();
+
+    /**
+     * Determines if this converter is applicable for converting to PlayerVaults.
+     * This may check for the existance of a plugin, plugin folder, or otherwise.
+     *
+     * @return true if this converter can convert, false otherwise
+     */
+    public boolean canConvert();
+
+    /**
+     * Gets the name of this converter
+     *
+     * @return the converter name
+     */
+    public String getName();
+
+}