Class SystemVersion

Method Details

• isWindows

  public static boolean isWindows()

• isMac

  public static boolean isMac()

• isAndroid

  public static boolean isAndroid()

• isApache

  public static boolean isApache()

  Apache Harmony JVM, or Android

• isGNU

  public static boolean isGNU()

  gij or JamVM with GNU Classpath

• isGentoo

  public static boolean isGentoo()

  Since:

  0.9.23

• isOpenJDK

  public static boolean isOpenJDK()

  Since:

  0.9.26

• isARM

  public static boolean isARM()

  Since:

  0.9.8 speed: do not cripple down for powerful ARM

• isX86

  public static boolean isX86()

  Since:

  0.9.14

• isZeroVM

  public static boolean isZeroVM()

  Is this a very slow interpreted mode VM?

  Since:

  0.9.38

• isSlow

  public static boolean isSlow()

  Our best guess on whether this is a slow architecture / OS / JVM, using some simple heuristics.

  Since:

  0.9.30

• isJava6

  public static boolean isJava6()

  Better than (new VersionComparator()).compare(System.getProperty("java.version"), "1.6") >= 0 as it handles Android also, where java.version = "0".

  Returns:

  true if Java 1.6 or higher, or Android API 9 or higher

• isJava7

  public static boolean isJava7()

  Better than (new VersionComparator()).compare(System.getProperty("java.version"), "1.7") >= 0 as it handles Android also, where java.version = "0".

  Returns:

  true if Java 1.7 or higher, or Android API 19 or higher

  Since:

  0.9.14

• isJava8

  public static boolean isJava8()

  Returns:

  true if Java 1.8 or higher, false for Android.

  Since:

  0.9.15

• isJava9

  public static boolean isJava9()

  Returns:

  true if Java 9 or higher, false for Android.

  Since:

  0.9.23

• isJava10

  public static boolean isJava10()

  Returns:

  true if Java 10 or higher, false for Android.

  Since:

  0.9.33

• isJava11

  public static boolean isJava11()

  Returns:

  true if Java 11 or higher, false for Android.

  Since:

  0.9.35

• isJava

  public static boolean isJava​(int minVersion)

  Handles Android also

  Parameters:

  minVersion - e.g. 11

  Returns:

  true if greater than or equal to minVersion

  Since:

  0.9.41

• isJava

  public static boolean isJava​(String minVersion)

  Handles Android, and minVersions in both forms (e.g. 11 or 1.11)

  Parameters:

  minVersion - either 1.x or x form works

  Returns:

  true if greater than or equal to minVersion

  Since:

  0.9.41

• is64Bit

  public static boolean is64Bit()

  This isn't always correct. http://stackoverflow.com/questions/807263/how-do-i-detect-which-kind-of-jre-is-installed-32bit-vs-64bit http://mark.koli.ch/2009/10/javas-osarch-system-property-is-the-bitness-of-the-jre-not-the-operating-system.html http://mark.koli.ch/2009/10/reliably-checking-os-bitness-32-or-64-bit-on-windows-with-a-tiny-c-app.html sun.arch.data.model not on all JVMs sun.arch.data.model == 64 => 64 bit processor sun.arch.data.model == 32 => A 32 bit JVM but could be either 32 or 64 bit processor or libs os.arch contains "64" could be 32 or 64 bit libs

• isLinuxService

  public static boolean isLinuxService()

• isWindowsService

  public static boolean isWindowsService()

• isService

  public static boolean isService()

• getAndroidVersion

  public static int getAndroidVersion()

  Identical to android.os.Build.VERSION.SDK_INT. For use outside of Android code.

  Returns:

  The SDK (API) version, e.g. 8 for Froyo, 0 if unknown

• hasWrapper

  public static boolean hasWrapper()

  Is the wrapper present? Same as I2PAppContext.hasWrapper()

• getMaxMemory

  public static long getMaxMemory()

  Runtime.getRuntime().maxMemory() but check for bogus values

  Since:

  0.9.8

• getCores

  public static int getCores()

  Runtime.getRuntime().availableProcssors()

  Returns:

  never smaller than 1

  Since:

  0.9.34

• usableCores

  public static int usableCores()

  calculate how many (virtual) cores should be actually used by a thread pool

• getSystemTimeZone

  public static TimeZone getSystemTimeZone()

  The system's time zone, which is probably different from the JVM time zone, because Router changes the JVM default to GMT. It saves the old default in the context properties where we can get it. Use this to format a time in local time zone with DateFormat.setTimeZone().

  Returns:

  non-null

  Since:

  0.9.24

• getSystemTimeZone

  public static TimeZone getSystemTimeZone​(I2PAppContext ctx)

  The system's time zone, which is probably different from the JVM time zone, because Router changes the JVM default to GMT. It saves the old default in the context properties where we can get it. Use this to format a time in local time zone with DateFormat.setTimeZone().

  Returns:

  non-null

  Since:

  0.9.24

• main

  public static void main​(String[] args)

  Since:

  0.9.24