java.lang.Object
- net.i2p.util.SystemVersion

```
public abstract class SystemVersion
extends Object
```
Methods to find out what system we are running on

Since:

0.9.3 consolidated from various places

Field Summary

Fields
Modifier and Type Field Description

static String DAEMON_USER

static String GENTOO_USER

Constructor Summary

Constructors
Constructor Description

SystemVersion()

Method Summary

All Methods Static Methods Concrete Methods
Modifier and Type	Method	Description
`static int`	`getAndroidVersion()`	Identical to android.os.Build.VERSION.SDK_INT.
`static int`	`getCores()`	Runtime.getRuntime().availableProcssors()
`static long`	`getMaxMemory()`	Runtime.getRuntime().maxMemory() but check for bogus values
`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.
`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.
`static boolean`	`hasWrapper()`	Is the wrapper present? Same as I2PAppContext.hasWrapper()
`static boolean`	`is64Bit()`	This isn't always correct.
`static boolean`	`isAndroid()`
`static boolean`	`isApache()`	Apache Harmony JVM, or Android
`static boolean`	`isARM()`
`static boolean`	`isGentoo()`
`static boolean`	`isGNU()`	gij or JamVM with GNU Classpath
`static boolean`	`isJava(int minVersion)`	Handles Android also
`static boolean`	`isJava(String minVersion)`	Handles Android, and minVersions in both forms (e.g.
`static boolean`	`isJava10()`
`static boolean`	`isJava11()`
`static boolean`	`isJava6()`	Better than (new VersionComparator()).compare(System.getProperty("java.version"), "1.6") >= 0 as it handles Android also, where java.version = "0".
`static boolean`	`isJava7()`	Better than (new VersionComparator()).compare(System.getProperty("java.version"), "1.7") >= 0 as it handles Android also, where java.version = "0".
`static boolean`	`isJava8()`
`static boolean`	`isJava9()`
`static boolean`	`isLinuxService()`
`static boolean`	`isMac()`
`static boolean`	`isOpenJDK()`
`static boolean`	`isService()`
`static boolean`	`isSlow()`	Our best guess on whether this is a slow architecture / OS / JVM, using some simple heuristics.
`static boolean`	`isWindows()`
`static boolean`	`isWindowsService()`
`static boolean`	`isX86()`
`static boolean`	`isZeroVM()`	Is this a very slow interpreted mode VM?
`static void`	`main(String[] args)`

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Field Detail
  - DAEMON_USER
```
public static final String DAEMON_USER
```
    See Also:
    
    Constant Field Values
  - GENTOO_USER
```
public static final String GENTOO_USER
```
    See Also:
    
    Constant Field Values
- Constructor Detail
  - SystemVersion
```
public SystemVersion()
```
- Method Detail
  - 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
  - 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
  - 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

Class SystemVersion

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

DAEMON_USER

GENTOO_USER

Constructor Detail

SystemVersion

Method Detail

isWindows

isMac

isAndroid

isApache

isGNU

isGentoo

isOpenJDK

isARM

isX86

isZeroVM

isSlow

isJava6

isJava7

isJava8

isJava9

isJava10

isJava11

isJava

isJava

is64Bit

isLinuxService

isWindowsService

isService

getAndroidVersion

hasWrapper

getMaxMemory

getCores

getSystemTimeZone

getSystemTimeZone

main