src/main/java/com/irtimaled/bbor/config/Configuration.java

   1 package com.irtimaled.bbor.config;
   2
   3 import com.google.common.io.Files;
   4
   5 import java.io.*;
   6 import java.nio.charset.Charset;
   7 import java.nio.charset.StandardCharsets;
   8 import java.util.HashMap;
   9 import java.util.List;
  10 import java.util.Map;
  11
  12 public class Configuration {
  13     public static final String FALLBACK_CATEGORY = "features";
  14     private final File file;
  15
  16     Configuration(File file) {
  17         this.file = file;
  18     }
  19
  20     void save() {
  21         try (Writer writer = new BufferedWriter(new OutputStreamWriter(new FileOutputStream(file), StandardCharsets.UTF_8))) {
  22             writer.write("# Configuration file\n");
  23             for (String category : settingsGroup.keySet()) {
  24                 writer.write("\n");
  25                 writer.write(String.format("%s {\n", category));
  26                 Map<String, Setting<?>> settings = settingsGroup.get(category);
  27                 boolean first = true;
  28                 for (String settingName : settings.keySet()) {
  29                     if (!first)
  30                         writer.write("\n");
  31                     first = false;
  32                     Setting setting = settings.get(settingName);
  33                     writer.write(String.format("    # %s\n", setting.comment));
  34                     writer.write(String.format("    %s:%s=%s\n", setting.getType(), settingName, setting.getValue()));
  35                 }
  36                 writer.write("}\n");
  37             }
  38         } catch (IOException ignored) {
  39         }
  40     }
  41
  42     private Map<String, Map<String, Setting<?>>> settingsGroup = new HashMap<>();
  43
  44     void load() {
  45         try {
  46             List<String> lines = Files.readLines(file, Charset.forName("utf-8"));
  47             String category = null;
  48             String lastCommentLine = null;
  49             for (String line : lines) {
  50                 String trimmedLine = line.trim();
  51                 if (trimmedLine.isEmpty()) {
  52                     continue;
  53                 }
  54                 if (trimmedLine.startsWith("#")) {
  55                     lastCommentLine = trimmedLine.substring(1).trim();
  56                     continue;
  57                 }
  58                 if (trimmedLine.equals("}")) {
  59                     category = null;
  60                     continue;
  61                 }
  62                 if (category == null && trimmedLine.endsWith("{")) {
  63                     category = trimmedLine.substring(0, trimmedLine.length() - 1).trim();
  64                     settingsGroup.put(category, new HashMap<>());
  65                     continue;
  66                 }
  67                 if (category != null) {
  68                     String[] items = trimmedLine.split("[:=]");
  69                     char type = items[0].charAt(0);
  70                     String name = items[1];
  71                     String stringValue = items[2];
  72                     Setting setting = getTypedSetting(type, stringValue);
  73                     setting.comment = lastCommentLine;
  74                     settingsGroup.get(category).put(name, setting);
  75                 }
  76             }
  77         } catch (IOException ignored) {
  78         }
  79     }
  80
  81     private Setting<?> getTypedSetting(char type, String value) {
  82         switch (type) {
  83             case 'I':
  84                 return new Setting<>(type, Integer.parseInt(value));
  85             case 'B':
  86                 return new Setting<>(type, value.equals("1") || value.toLowerCase().equals("true"));
  87         }
  88         return new Setting<>(type, value);
  89     }
  90
  91     <T> Setting<T> get(String category, String settingName, T defaultValue) {
  92         char type = getType(defaultValue);
  93         if (!settingsGroup.containsKey(category)) {
  94             settingsGroup.put(category, new HashMap<>());
  95         }
  96         Map<String, Setting<?>> settings = settingsGroup.get(category);
  97         Setting<?> setting = settings.get(settingName);
  98         if (setting == null && category != FALLBACK_CATEGORY)
  99             setting = getFallbackSetting(settingName, settings);
 100         if (setting != null && setting.getType() != type) {
 101             setting = null;
 102         }
 103         if (setting == null) {
 104             settings.put(settingName, setting = new Setting<>(type, defaultValue));
 105         }
 106         return (Setting<T>) setting;
 107     }
 108
 109     private Setting<?> getFallbackSetting(String settingName, Map<String, Setting<?>> settings) {
 110         Map<String, Setting<?>> fallbackSettings = settingsGroup.get(FALLBACK_CATEGORY);
 111         if (fallbackSettings == null) return null;
 112
 113         Setting<?> setting = fallbackSettings.get(settingName);
 114         if (setting != null) {
 115             fallbackSettings.remove(settingName);
 116             settings.put(settingName, setting);
 117         }
 118         return setting;
 119     }
 120
 121     private <T> char getType(T defaultValue) {
 122         String[] typeNames = defaultValue.getClass().getName().split("[.]");
 123         return typeNames[typeNames.length - 1].charAt(0);
 124     }
 125
 126     void put(Setting<?> setting) {
 127         String category = setting.category;
 128         if (!settingsGroup.containsKey(category)) {
 129             settingsGroup.put(category, new HashMap<>());
 130         }
 131         Map<String, Setting<?>> settings = settingsGroup.get(category);
 132         settings.put(setting.name, setting);
 133     }
 134 }