src/charactermanaj/util/JavaVersionUtils.java

   1 package charactermanaj.util;\r
   2 \r
   3 \r
   4 public final class JavaVersionUtils {\r
   5 \r
   6         private JavaVersionUtils() {\r
   7                 super();\r
   8         }\r
   9 \r
  10         /**\r
  11          * Javaの簡易なバージョンを取得する.<br>\r
  12          * 不明な場合は0を返す.<br>\r
  13          * \r
  14          * @return バージョン\r
  15          */\r
  16         public static double getJavaVersion() {\r
  17                 try {\r
  18                         String version = System.getProperty("java.version");\r
  19                         String[] versions = version.split("\\.");\r
  20                         if (versions.length > 2) {\r
  21                                 return Double.valueOf(versions[0] + "." + versions[1]);\r
  22                         }\r
  23                 } catch (RuntimeException ex) {\r
  24                         ex.printStackTrace();\r
  25                 }\r
  26                 return 0d;\r
  27         }\r
  28 \r
  29         /**\r
  30          * Javaの詳細なバージョンを取得する. メジャー・マイナー・メンテナンス・アップデートの4要素を返す.<br>\r
  31          * \r
  32          * @return\r
  33          */\r
  34         public static int[] getJavaVersions() {\r
  35                 return getJavaVersions(System.getProperty("java.version"));\r
  36         }\r
  37 \r
  38         private static int[] getJavaVersions(String version) {\r
  39                 int[] ret = new int[4];\r
  40                 try {\r
  41                         int posIdentifier = version.indexOf('-');\r
  42                         if (posIdentifier >= 0) {\r
  43                                 version = version.substring(0, posIdentifier);\r
  44                         }\r
  45 \r
  46                         int posUpdate = version.indexOf("_");\r
  47                         int update = 0;\r
  48                         if (posUpdate >= 0) {\r
  49                                 update = Integer.parseInt(version.substring(posUpdate + 1));\r
  50                                 version = version.substring(0, posUpdate);\r
  51                         }\r
  52 \r
  53                         String[] versions = version.split("\\.");\r
  54 \r
  55                         for (int idx = 0; idx < 3 && idx < versions.length; idx++) {\r
  56                                 ret[idx] = Integer.parseInt(versions[idx]);\r
  57                         }\r
  58                         ret[3] = update;\r
  59 \r
  60                 } catch (RuntimeException ex) {\r
  61                         ex.printStackTrace();\r
  62                 }\r
  63                 return ret;\r
  64         }\r
  65 }\r