java.lang.Object
- org.apache.commons.lang.SystemUtils

```
public class SystemUtils
extends Object
```
Helpers for java.lang.System.

If a system property cannot be read due to security restrictions, the corresponding field in this class will be set to null and a message will be written to System.err.

#ThreadSafe#

Since:

1.0

Version:

$Id: SystemUtils.java 1056988 2011-01-09 17:58:53Z niallp $

Field Summary

Fields
Modifier and Type	Field	Description
`static String`	`AWT_TOOLKIT`	The `awt.toolkit` System Property.
`static String`	`FILE_ENCODING`	The `file.encoding` System Property.
`static String`	`FILE_SEPARATOR`	The `file.separator` System Property.
`static boolean`	`IS_JAVA_1_1`	Is `true` if this is Java version 1.1 (also 1.1.x versions).
`static boolean`	`IS_JAVA_1_2`	Is `true` if this is Java version 1.2 (also 1.2.x versions).
`static boolean`	`IS_JAVA_1_3`	Is `true` if this is Java version 1.3 (also 1.3.x versions).
`static boolean`	`IS_JAVA_1_4`	Is `true` if this is Java version 1.4 (also 1.4.x versions).
`static boolean`	`IS_JAVA_1_5`	Is `true` if this is Java version 1.5 (also 1.5.x versions).
`static boolean`	`IS_JAVA_1_6`	Is `true` if this is Java version 1.6 (also 1.6.x versions).
`static boolean`	`IS_JAVA_1_7`	Is `true` if this is Java version 1.7 (also 1.7.x versions).
`static boolean`	`IS_OS_AIX`	Is `true` if this is AIX.
`static boolean`	`IS_OS_HP_UX`	Is `true` if this is HP-UX.
`static boolean`	`IS_OS_IRIX`	Is `true` if this is Irix.
`static boolean`	`IS_OS_LINUX`	Is `true` if this is Linux.
`static boolean`	`IS_OS_MAC`	Is `true` if this is Mac.
`static boolean`	`IS_OS_MAC_OSX`	Is `true` if this is Mac.
`static boolean`	`IS_OS_OS2`	Is `true` if this is OS/2.
`static boolean`	`IS_OS_SOLARIS`	Is `true` if this is Solaris.
`static boolean`	`IS_OS_SUN_OS`	Is `true` if this is SunOS.
`static boolean`	`IS_OS_UNIX`	Is `true` if this is a UNIX like system, as in any of AIX, HP-UX, Irix, Linux, MacOSX, Solaris or SUN OS.
`static boolean`	`IS_OS_WINDOWS`	Is `true` if this is Windows.
`static boolean`	`IS_OS_WINDOWS_2000`	Is `true` if this is Windows 2000.
`static boolean`	`IS_OS_WINDOWS_7`	Is `true` if this is Windows 7.
`static boolean`	`IS_OS_WINDOWS_95`	Is `true` if this is Windows 95.
`static boolean`	`IS_OS_WINDOWS_98`	Is `true` if this is Windows 98.
`static boolean`	`IS_OS_WINDOWS_ME`	Is `true` if this is Windows ME.
`static boolean`	`IS_OS_WINDOWS_NT`	Is `true` if this is Windows NT.
`static boolean`	`IS_OS_WINDOWS_VISTA`	Is `true` if this is Windows Vista.
`static boolean`	`IS_OS_WINDOWS_XP`	Is `true` if this is Windows XP.
`static String`	`JAVA_AWT_FONTS`	The `java.awt.fonts` System Property.
`static String`	`JAVA_AWT_GRAPHICSENV`	The `java.awt.graphicsenv` System Property.
`static String`	`JAVA_AWT_HEADLESS`	The `java.awt.headless` System Property.
`static String`	`JAVA_AWT_PRINTERJOB`	The `java.awt.printerjob` System Property.
`static String`	`JAVA_CLASS_PATH`	The `java.class.path` System Property.
`static String`	`JAVA_CLASS_VERSION`	The `java.class.version` System Property.
`static String`	`JAVA_COMPILER`	The `java.compiler` System Property.
`static String`	`JAVA_ENDORSED_DIRS`	The `java.endorsed.dirs` System Property.
`static String`	`JAVA_EXT_DIRS`	The `java.ext.dirs` System Property.
`static String`	`JAVA_HOME`	The `java.home` System Property.
`static String`	`JAVA_IO_TMPDIR`	The `java.io.tmpdir` System Property.
`static String`	`JAVA_LIBRARY_PATH`	The `java.library.path` System Property.
`static String`	`JAVA_RUNTIME_NAME`	The `java.runtime.name` System Property.
`static String`	`JAVA_RUNTIME_VERSION`	The `java.runtime.version` System Property.
`static String`	`JAVA_SPECIFICATION_NAME`	The `java.specification.name` System Property.
`static String`	`JAVA_SPECIFICATION_VENDOR`	The `java.specification.vendor` System Property.
`static String`	`JAVA_SPECIFICATION_VERSION`	The `java.specification.version` System Property.
`static String`	`JAVA_UTIL_PREFS_PREFERENCES_FACTORY`	The `java.util.prefs.PreferencesFactory` System Property.
`static String`	`JAVA_VENDOR`	The `java.vendor` System Property.
`static String`	`JAVA_VENDOR_URL`	The `java.vendor.url` System Property.
`static String`	`JAVA_VERSION`	The `java.version` System Property.
`static float`	`JAVA_VERSION_FLOAT`	Gets the Java version as a `float`.
`static int`	`JAVA_VERSION_INT`	Gets the Java version as an `int`.
`static String`	`JAVA_VERSION_TRIMMED`	Gets the Java version as a `String` trimming leading letters.
`static String`	`JAVA_VM_INFO`	The `java.vm.info` System Property.
`static String`	`JAVA_VM_NAME`	The `java.vm.name` System Property.
`static String`	`JAVA_VM_SPECIFICATION_NAME`	The `java.vm.specification.name` System Property.
`static String`	`JAVA_VM_SPECIFICATION_VENDOR`	The `java.vm.specification.vendor` System Property.
`static String`	`JAVA_VM_SPECIFICATION_VERSION`	The `java.vm.specification.version` System Property.
`static String`	`JAVA_VM_VENDOR`	The `java.vm.vendor` System Property.
`static String`	`JAVA_VM_VERSION`	The `java.vm.version` System Property.
`static String`	`LINE_SEPARATOR`	The `line.separator` System Property.
`static String`	`OS_ARCH`	The `os.arch` System Property.
`static String`	`OS_NAME`	The `os.name` System Property.
`static String`	`OS_VERSION`	The `os.version` System Property.
`static String`	`PATH_SEPARATOR`	The `path.separator` System Property.
`static String`	`USER_COUNTRY`	The `user.country` or `user.region` System Property.
`static String`	`USER_DIR`	The `user.dir` System Property.
`static String`	`USER_HOME`	The `user.home` System Property.
`static String`	`USER_LANGUAGE`	The `user.language` System Property.
`static String`	`USER_NAME`	The `user.name` System Property.
`static String`	`USER_TIMEZONE`	The `user.timezone` System Property.

Constructor Summary

Constructors
Constructor Description

SystemUtils()
SystemUtils instances should NOT be constructed in standard programming.

Method Summary

All Methods Static Methods Concrete Methods Deprecated Methods
Modifier and Type	Method	Description
`static File`	`getJavaHome()`	Gets the Java home directory as a `File`.
`static File`	`getJavaIoTmpDir()`	Gets the Java IO temporary directory as a `File`.
`static float`	`getJavaVersion()`	Deprecated. Use `JAVA_VERSION_FLOAT` instead.
`static File`	`getUserDir()`	Gets the user directory as a `File`.
`static File`	`getUserHome()`	Gets the user home directory as a `File`.
`static boolean`	`isJavaAwtHeadless()`	Returns whether the `JAVA_AWT_HEADLESS` value is `true`.
`static boolean`	`isJavaVersionAtLeast(float requiredVersion)`	Is the Java version at least the requested version.
`static boolean`	`isJavaVersionAtLeast(int requiredVersion)`	Is the Java version at least the requested version.

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

- Field Detail
  - AWT_TOOLKIT
```
public static final String AWT_TOOLKIT
```
    The awt.toolkit System Property.
    
    Holds a class name, on Windows XP this is sun.awt.windows.WToolkit.
    
    On platforms without a GUI, this value is null.
    
    Defaults to null if the runtime does not have security access to read this property or the property does not exist.
    
    This value is initialized when the class is loaded. If System.setProperty(String,String) or System.setProperties(java.util.Properties) is called after this class is loaded, the value will be out of sync with that System property.
    
    Since:
    
    2.1
  - FILE_ENCODING
```
public static final String FILE_ENCODING
```
    The file.encoding System Property.
    
    File encoding, such as Cp1252.
    
    Defaults to null if the runtime does not have security access to read this property or the property does not exist.
    
    This value is initialized when the class is loaded. If System.setProperty(String,String) or System.setProperties(java.util.Properties) is called after this class is loaded, the value will be out of sync with that System property.
    
    Since:
    
    2.0, Java 1.2
  - FILE_SEPARATOR
```
public static final String FILE_SEPARATOR
```
    The file.separator System Property. File separator ("/" on UNIX).
    
    Defaults to null if the runtime does not have security access to read this property or the property does not exist.
    
    This value is initialized when the class is loaded. If System.setProperty(String,String) or System.setProperties(java.util.Properties) is called after this class is loaded, the value will be out of sync with that System property.
    
    Since:
    
    Java 1.1
  - JAVA_AWT_FONTS
```
public static final String JAVA_AWT_FONTS
```
    The java.awt.fonts System Property.
    
    Defaults to null if the runtime does not have security access to read this property or the property does not exist.
    
    This value is initialized when the class is loaded. If System.setProperty(String,String) or System.setProperties(java.util.Properties) is called after this class is loaded, the value will be out of sync with that System property.
    
    Since:
    
    2.1
  - JAVA_AWT_GRAPHICSENV
```
public static final String JAVA_AWT_GRAPHICSENV
```
    The java.awt.graphicsenv System Property.
    
    Defaults to null if the runtime does not have security access to read this property or the property does not exist.
    
    This value is initialized when the class is loaded. If System.setProperty(String,String) or System.setProperties(java.util.Properties) is called after this class is loaded, the value will be out of sync with that System property.
    
    Since:
    
    2.1
  - JAVA_AWT_HEADLESS
```
public static final String JAVA_AWT_HEADLESS
```
    The java.awt.headless System Property. The value of this property is the String "true" or "false".
    
    Defaults to null if the runtime does not have security access to read this property or the property does not exist.
    
    This value is initialized when the class is loaded. If System.setProperty(String,String) or System.setProperties(java.util.Properties) is called after this class is loaded, the value will be out of sync with that System property.
    
    Since:
    
    2.1, Java 1.4
    
    See Also:
    
    isJavaAwtHeadless()
  - JAVA_AWT_PRINTERJOB
```
public static final String JAVA_AWT_PRINTERJOB
```
    The java.awt.printerjob System Property.
    
    Defaults to null if the runtime does not have security access to read this property or the property does not exist.
    
    This value is initialized when the class is loaded. If System.setProperty(String,String) or System.setProperties(java.util.Properties) is called after this class is loaded, the value will be out of sync with that System property.
    
    Since:
    
    2.1
  - JAVA_CLASS_PATH
```
public static final String JAVA_CLASS_PATH
```
    The java.class.path System Property. Java class path.
    
    Defaults to null if the runtime does not have security access to read this property or the property does not exist.
    
    This value is initialized when the class is loaded. If System.setProperty(String,String) or System.setProperties(java.util.Properties) is called after this class is loaded, the value will be out of sync with that System property.
    
    Since:
    
    Java 1.1
  - JAVA_CLASS_VERSION
```
public static final String JAVA_CLASS_VERSION
```
    The java.class.version System Property. Java class format version number.
    
    Defaults to null if the runtime does not have security access to read this property or the property does not exist.
    
    This value is initialized when the class is loaded. If System.setProperty(String,String) or System.setProperties(java.util.Properties) is called after this class is loaded, the value will be out of sync with that System property.
    
    Since:
    
    Java 1.1
  - JAVA_COMPILER
```
public static final String JAVA_COMPILER
```
    The java.compiler System Property. Name of JIT compiler to use. First in JDK version 1.2. Not used in Sun JDKs after 1.2.
    
    Defaults to null if the runtime does not have security access to read this property or the property does not exist.
    
    This value is initialized when the class is loaded. If System.setProperty(String,String) or System.setProperties(java.util.Properties) is called after this class is loaded, the value will be out of sync with that System property.
    
    Since:
    
    Java 1.2. Not used in Sun versions after 1.2.
  - JAVA_ENDORSED_DIRS
```
public static final String JAVA_ENDORSED_DIRS
```
    The java.endorsed.dirs System Property. Path of endorsed directory or directories.
    
    Defaults to null if the runtime does not have security access to read this property or the property does not exist.
    
    This value is initialized when the class is loaded. If System.setProperty(String,String) or System.setProperties(java.util.Properties) is called after this class is loaded, the value will be out of sync with that System property.
    
    Since:
    
    Java 1.4
  - JAVA_EXT_DIRS
```
public static final String JAVA_EXT_DIRS
```
    The java.ext.dirs System Property. Path of extension directory or directories.
    
    Defaults to null if the runtime does not have security access to read this property or the property does not exist.
    
    This value is initialized when the class is loaded. If System.setProperty(String,String) or System.setProperties(java.util.Properties) is called after this class is loaded, the value will be out of sync with that System property.
    
    Since:
    
    Java 1.3
  - JAVA_HOME
```
public static final String JAVA_HOME
```
    The java.home System Property. Java installation directory.
    
    Defaults to null if the runtime does not have security access to read this property or the property does not exist.
    
    This value is initialized when the class is loaded. If System.setProperty(String,String) or System.setProperties(java.util.Properties) is called after this class is loaded, the value will be out of sync with that System property.
    
    Since:
    
    Java 1.1
  - JAVA_IO_TMPDIR
```
public static final String JAVA_IO_TMPDIR
```
    The java.io.tmpdir System Property. Default temp file path.
    
    Defaults to null if the runtime does not have security access to read this property or the property does not exist.
    
    This value is initialized when the class is loaded. If System.setProperty(String,String) or System.setProperties(java.util.Properties) is called after this class is loaded, the value will be out of sync with that System property.
    
    Since:
    
    Java 1.2
  - JAVA_LIBRARY_PATH
```
public static final String JAVA_LIBRARY_PATH
```
    The java.library.path System Property. List of paths to search when loading libraries.
    
    Defaults to null if the runtime does not have security access to read this property or the property does not exist.
    
    This value is initialized when the class is loaded. If System.setProperty(String,String) or System.setProperties(java.util.Properties) is called after this class is loaded, the value will be out of sync with that System property.
    
    Since:
    
    Java 1.2
  - JAVA_RUNTIME_NAME
```
public static final String JAVA_RUNTIME_NAME
```
    The java.runtime.name System Property. Java Runtime Environment name.
    
    Defaults to null if the runtime does not have security access to read this property or the property does not exist.
    
    This value is initialized when the class is loaded. If System.setProperty(String,String) or System.setProperties(java.util.Properties) is called after this class is loaded, the value will be out of sync with that System property.
    
    Since:
    
    2.0, Java 1.3
  - JAVA_RUNTIME_VERSION
```
public static final String JAVA_RUNTIME_VERSION
```
    The java.runtime.version System Property. Java Runtime Environment version.
    
    Defaults to null if the runtime does not have security access to read this property or the property does not exist.
    
    This value is initialized when the class is loaded. If System.setProperty(String,String) or System.setProperties(java.util.Properties) is called after this class is loaded, the value will be out of sync with that System property.
    
    Since:
    
    2.0, Java 1.3
  - JAVA_SPECIFICATION_NAME
```
public static final String JAVA_SPECIFICATION_NAME
```
    The java.specification.name System Property. Java Runtime Environment specification name.
    
    Defaults to null if the runtime does not have security access to read this property or the property does not exist.
    
    This value is initialized when the class is loaded. If System.setProperty(String,String) or System.setProperties(java.util.Properties) is called after this class is loaded, the value will be out of sync with that System property.
    
    Since:
    
    Java 1.2
  - JAVA_SPECIFICATION_VENDOR
```
public static final String JAVA_SPECIFICATION_VENDOR
```
    The java.specification.vendor System Property. Java Runtime Environment specification vendor.
    
    Defaults to null if the runtime does not have security access to read this property or the property does not exist.
    
    This value is initialized when the class is loaded. If System.setProperty(String,String) or System.setProperties(java.util.Properties) is called after this class is loaded, the value will be out of sync with that System property.
    
    Since:
    
    Java 1.2
  - JAVA_SPECIFICATION_VERSION
```
public static final String JAVA_SPECIFICATION_VERSION
```
    The java.specification.version System Property. Java Runtime Environment specification version.
    
    Defaults to null if the runtime does not have security access to read this property or the property does not exist.
    
    This value is initialized when the class is loaded. If System.setProperty(String,String) or System.setProperties(java.util.Properties) is called after this class is loaded, the value will be out of sync with that System property.
    
    Since:
    
    Java 1.3
  - JAVA_UTIL_PREFS_PREFERENCES_FACTORY
```
public static final String JAVA_UTIL_PREFS_PREFERENCES_FACTORY
```
    The java.util.prefs.PreferencesFactory System Property. A class name.
    
    Defaults to null if the runtime does not have security access to read this property or the property does not exist.
    
    This value is initialized when the class is loaded. If System.setProperty(String,String) or System.setProperties(java.util.Properties) is called after this class is loaded, the value will be out of sync with that System property.
    
    Since:
    
    2.1, Java 1.4
  - JAVA_VENDOR
```
public static final String JAVA_VENDOR
```
    The java.vendor System Property. Java vendor-specific string.
    
    Defaults to null if the runtime does not have security access to read this property or the property does not exist.
    
    This value is initialized when the class is loaded. If System.setProperty(String,String) or System.setProperties(java.util.Properties) is called after this class is loaded, the value will be out of sync with that System property.
    
    Since:
    
    Java 1.1
  - JAVA_VENDOR_URL
```
public static final String JAVA_VENDOR_URL
```
    The java.vendor.url System Property. Java vendor URL.
    
    Defaults to null if the runtime does not have security access to read this property or the property does not exist.
    
    This value is initialized when the class is loaded. If System.setProperty(String,String) or System.setProperties(java.util.Properties) is called after this class is loaded, the value will be out of sync with that System property.
    
    Since:
    
    Java 1.1
  - JAVA_VERSION
```
public static final String JAVA_VERSION
```
    The java.version System Property. Java version number.
    
    Defaults to null if the runtime does not have security access to read this property or the property does not exist.
    
    This value is initialized when the class is loaded. If System.setProperty(String,String) or System.setProperties(java.util.Properties) is called after this class is loaded, the value will be out of sync with that System property.
    
    Since:
    
    Java 1.1
  - JAVA_VM_INFO
```
public static final String JAVA_VM_INFO
```
    The java.vm.info System Property. Java Virtual Machine implementation info.
    
    Defaults to null if the runtime does not have security access to read this property or the property does not exist.
    
    This value is initialized when the class is loaded. If System.setProperty(String,String) or System.setProperties(java.util.Properties) is called after this class is loaded, the value will be out of sync with that System property.
    
    Since:
    
    2.0, Java 1.2
  - JAVA_VM_NAME
```
public static final String JAVA_VM_NAME
```
    The java.vm.name System Property. Java Virtual Machine implementation name.
    
    Defaults to null if the runtime does not have security access to read this property or the property does not exist.
    
    This value is initialized when the class is loaded. If System.setProperty(String,String) or System.setProperties(java.util.Properties) is called after this class is loaded, the value will be out of sync with that System property.
    
    Since:
    
    Java 1.2
  - JAVA_VM_SPECIFICATION_NAME
```
public static final String JAVA_VM_SPECIFICATION_NAME
```
    The java.vm.specification.name System Property. Java Virtual Machine specification name.
    
    Defaults to null if the runtime does not have security access to read this property or the property does not exist.
    
    This value is initialized when the class is loaded. If System.setProperty(String,String) or System.setProperties(java.util.Properties) is called after this class is loaded, the value will be out of sync with that System property.
    
    Since:
    
    Java 1.2
  - JAVA_VM_SPECIFICATION_VENDOR
```
public static final String JAVA_VM_SPECIFICATION_VENDOR
```
    The java.vm.specification.vendor System Property. Java Virtual Machine specification vendor.
    
    Defaults to null if the runtime does not have security access to read this property or the property does not exist.
    
    This value is initialized when the class is loaded. If System.setProperty(String,String) or System.setProperties(java.util.Properties) is called after this class is loaded, the value will be out of sync with that System property.
    
    Since:
    
    Java 1.2
  - JAVA_VM_SPECIFICATION_VERSION
```
public static final String JAVA_VM_SPECIFICATION_VERSION
```
    The java.vm.specification.version System Property. Java Virtual Machine specification version.
    
    Defaults to null if the runtime does not have security access to read this property or the property does not exist.
    
    This value is initialized when the class is loaded. If System.setProperty(String,String) or System.setProperties(java.util.Properties) is called after this class is loaded, the value will be out of sync with that System property.
    
    Since:
    
    Java 1.2
  - JAVA_VM_VENDOR
```
public static final String JAVA_VM_VENDOR
```
    The java.vm.vendor System Property. Java Virtual Machine implementation vendor.
    
    Defaults to null if the runtime does not have security access to read this property or the property does not exist.
    
    This value is initialized when the class is loaded. If System.setProperty(String,String) or System.setProperties(java.util.Properties) is called after this class is loaded, the value will be out of sync with that System property.
    
    Since:
    
    Java 1.2
  - JAVA_VM_VERSION
```
public static final String JAVA_VM_VERSION
```
    The java.vm.version System Property. Java Virtual Machine implementation version.
    
    Defaults to null if the runtime does not have security access to read this property or the property does not exist.
    
    This value is initialized when the class is loaded. If System.setProperty(String,String) or System.setProperties(java.util.Properties) is called after this class is loaded, the value will be out of sync with that System property.
    
    Since:
    
    Java 1.2
  - LINE_SEPARATOR
```
public static final String LINE_SEPARATOR
```
    The line.separator System Property. Line separator ("\n" on UNIX).
    
    Defaults to null if the runtime does not have security access to read this property or the property does not exist.
    
    This value is initialized when the class is loaded. If System.setProperty(String,String) or System.setProperties(java.util.Properties) is called after this class is loaded, the value will be out of sync with that System property.
    
    Since:
    
    Java 1.1
  - OS_ARCH
```
public static final String OS_ARCH
```
    The os.arch System Property. Operating system architecture.
    
    Defaults to null if the runtime does not have security access to read this property or the property does not exist.
    
    This value is initialized when the class is loaded. If System.setProperty(String,String) or System.setProperties(java.util.Properties) is called after this class is loaded, the value will be out of sync with that System property.
    
    Since:
    
    Java 1.1
  - OS_NAME
```
public static final String OS_NAME
```
    The os.name System Property. Operating system name.
    
    Defaults to null if the runtime does not have security access to read this property or the property does not exist.
    
    This value is initialized when the class is loaded. If System.setProperty(String,String) or System.setProperties(java.util.Properties) is called after this class is loaded, the value will be out of sync with that System property.
    
    Since:
    
    Java 1.1
  - OS_VERSION
```
public static final String OS_VERSION
```
    The os.version System Property. Operating system version.
    
    Defaults to null if the runtime does not have security access to read this property or the property does not exist.
    
    This value is initialized when the class is loaded. If System.setProperty(String,String) or System.setProperties(java.util.Properties) is called after this class is loaded, the value will be out of sync with that System property.
    
    Since:
    
    Java 1.1
  - PATH_SEPARATOR
```
public static final String PATH_SEPARATOR
```
    The path.separator System Property. Path separator (":" on UNIX).
    
    Defaults to null if the runtime does not have security access to read this property or the property does not exist.
    
    This value is initialized when the class is loaded. If System.setProperty(String,String) or System.setProperties(java.util.Properties) is called after this class is loaded, the value will be out of sync with that System property.
    
    Since:
    
    Java 1.1
  - USER_COUNTRY
```
public static final String USER_COUNTRY
```
    The user.country or user.region System Property. User's country code, such as GB. First in Java version 1.2 as user.region. Renamed to user.country in 1.4
    
    Defaults to null if the runtime does not have security access to read this property or the property does not exist.
    
    This value is initialized when the class is loaded. If System.setProperty(String,String) or System.setProperties(java.util.Properties) is called after this class is loaded, the value will be out of sync with that System property.
    
    Since:
    
    2.0, Java 1.2
  - USER_DIR
```
public static final String USER_DIR
```
    The user.dir System Property. User's current working directory.
    
    Defaults to null if the runtime does not have security access to read this property or the property does not exist.
    
    This value is initialized when the class is loaded. If System.setProperty(String,String) or System.setProperties(java.util.Properties) is called after this class is loaded, the value will be out of sync with that System property.
    
    Since:
    
    Java 1.1
  - USER_HOME
```
public static final String USER_HOME
```
    The user.home System Property. User's home directory.
    
    Defaults to null if the runtime does not have security access to read this property or the property does not exist.
    
    This value is initialized when the class is loaded. If System.setProperty(String,String) or System.setProperties(java.util.Properties) is called after this class is loaded, the value will be out of sync with that System property.
    
    Since:
    
    Java 1.1
  - USER_LANGUAGE
```
public static final String USER_LANGUAGE
```
    The user.language System Property. User's language code, such as "en".
    
    Defaults to null if the runtime does not have security access to read this property or the property does not exist.
    
    This value is initialized when the class is loaded. If System.setProperty(String,String) or System.setProperties(java.util.Properties) is called after this class is loaded, the value will be out of sync with that System property.
    
    Since:
    
    2.0, Java 1.2
  - USER_NAME
```
public static final String USER_NAME
```
    The user.name System Property. User's account name.
    
    Defaults to null if the runtime does not have security access to read this property or the property does not exist.
    
    This value is initialized when the class is loaded. If System.setProperty(String,String) or System.setProperties(java.util.Properties) is called after this class is loaded, the value will be out of sync with that System property.
    
    Since:
    
    Java 1.1
  - USER_TIMEZONE
```
public static final String USER_TIMEZONE
```
    The user.timezone System Property. For example: "America/Los_Angeles".
    
    Defaults to null if the runtime does not have security access to read this property or the property does not exist.
    
    This value is initialized when the class is loaded. If System.setProperty(String,String) or System.setProperties(java.util.Properties) is called after this class is loaded, the value will be out of sync with that System property.
    
    Since:
    
    2.1
  - JAVA_VERSION_TRIMMED
```
public static final String JAVA_VERSION_TRIMMED
```
    Gets the Java version as a String trimming leading letters.
    
    The field will return null if JAVA_VERSION is null.
    
    Since:
    
    2.1
  - JAVA_VERSION_FLOAT
```
public static final float JAVA_VERSION_FLOAT
```
    Gets the Java version as a float.
    
    Example return values:
    
    1.2f for Java 1.2
    1.31f for Java 1.3.1
    
    The field will return zero if JAVA_VERSION is null.
    Since:
    
    2.0
  - JAVA_VERSION_INT
```
public static final int JAVA_VERSION_INT
```
    Gets the Java version as an int.
    
    Example return values:
    
    120 for Java 1.2
    131 for Java 1.3.1
    
    The field will return zero if JAVA_VERSION is null.
    Since:
    
    2.0
  - IS_JAVA_1_1
```
public static final boolean IS_JAVA_1_1
```
    Is true if this is Java version 1.1 (also 1.1.x versions).
    
    The field will return false if JAVA_VERSION is null.
  - IS_JAVA_1_2
```
public static final boolean IS_JAVA_1_2
```
    Is true if this is Java version 1.2 (also 1.2.x versions).
    
    The field will return false if JAVA_VERSION is null.
  - IS_JAVA_1_3
```
public static final boolean IS_JAVA_1_3
```
    Is true if this is Java version 1.3 (also 1.3.x versions).
    
    The field will return false if JAVA_VERSION is null.
  - IS_JAVA_1_4
```
public static final boolean IS_JAVA_1_4
```
    Is true if this is Java version 1.4 (also 1.4.x versions).
    
    The field will return false if JAVA_VERSION is null.
  - IS_JAVA_1_5
```
public static final boolean IS_JAVA_1_5
```
    Is true if this is Java version 1.5 (also 1.5.x versions).
    
    The field will return false if JAVA_VERSION is null.
  - IS_JAVA_1_6
```
public static final boolean IS_JAVA_1_6
```
    Is true if this is Java version 1.6 (also 1.6.x versions).
    
    The field will return false if JAVA_VERSION is null.
  - IS_JAVA_1_7
```
public static final boolean IS_JAVA_1_7
```
    Is true if this is Java version 1.7 (also 1.7.x versions).
    
    The field will return false if JAVA_VERSION is null.
    
    Since:
    
    2.5
  - IS_OS_AIX
```
public static final boolean IS_OS_AIX
```
    Is true if this is AIX.
    
    The field will return false if OS_NAME is null.
    
    Since:
    
    2.0
  - IS_OS_HP_UX
```
public static final boolean IS_OS_HP_UX
```
    Is true if this is HP-UX.
    
    The field will return false if OS_NAME is null.
    
    Since:
    
    2.0
  - IS_OS_IRIX
```
public static final boolean IS_OS_IRIX
```
    Is true if this is Irix.
    
    The field will return false if OS_NAME is null.
    
    Since:
    
    2.0
  - IS_OS_LINUX
```
public static final boolean IS_OS_LINUX
```
    Is true if this is Linux.
    
    The field will return false if OS_NAME is null.
    
    Since:
    
    2.0
  - IS_OS_MAC
```
public static final boolean IS_OS_MAC
```
    Is true if this is Mac.
    
    The field will return false if OS_NAME is null.
    
    Since:
    
    2.0
  - IS_OS_MAC_OSX
```
public static final boolean IS_OS_MAC_OSX
```
    Is true if this is Mac.
    
    The field will return false if OS_NAME is null.
    
    Since:
    
    2.0
  - IS_OS_OS2
```
public static final boolean IS_OS_OS2
```
    Is true if this is OS/2.
    
    The field will return false if OS_NAME is null.
    
    Since:
    
    2.0
  - IS_OS_SOLARIS
```
public static final boolean IS_OS_SOLARIS
```
    Is true if this is Solaris.
    
    The field will return false if OS_NAME is null.
    
    Since:
    
    2.0
  - IS_OS_SUN_OS
```
public static final boolean IS_OS_SUN_OS
```
    Is true if this is SunOS.
    
    The field will return false if OS_NAME is null.
    
    Since:
    
    2.0
  - IS_OS_UNIX
```
public static final boolean IS_OS_UNIX
```
    Is true if this is a UNIX like system, as in any of AIX, HP-UX, Irix, Linux, MacOSX, Solaris or SUN OS.
    
    The field will return false if OS_NAME is null.
    
    Since:
    
    2.1
  - IS_OS_WINDOWS
```
public static final boolean IS_OS_WINDOWS
```
    Is true if this is Windows.
    
    The field will return false if OS_NAME is null.
    
    Since:
    
    2.0
  - IS_OS_WINDOWS_2000
```
public static final boolean IS_OS_WINDOWS_2000
```
    Is true if this is Windows 2000.
    
    The field will return false if OS_NAME is null.
    
    Since:
    
    2.0
  - IS_OS_WINDOWS_95
```
public static final boolean IS_OS_WINDOWS_95
```
    Is true if this is Windows 95.
    
    The field will return false if OS_NAME is null.
    
    Since:
    
    2.0
  - IS_OS_WINDOWS_98
```
public static final boolean IS_OS_WINDOWS_98
```
    Is true if this is Windows 98.
    
    The field will return false if OS_NAME is null.
    
    Since:
    
    2.0
  - IS_OS_WINDOWS_ME
```
public static final boolean IS_OS_WINDOWS_ME
```
    Is true if this is Windows ME.
    
    The field will return false if OS_NAME is null.
    
    Since:
    
    2.0
  - IS_OS_WINDOWS_NT
```
public static final boolean IS_OS_WINDOWS_NT
```
    Is true if this is Windows NT.
    
    The field will return false if OS_NAME is null.
    
    Since:
    
    2.0
  - IS_OS_WINDOWS_XP
```
public static final boolean IS_OS_WINDOWS_XP
```
    Is true if this is Windows XP.
    
    The field will return false if OS_NAME is null.
    
    Since:
    
    2.0
  - IS_OS_WINDOWS_VISTA
```
public static final boolean IS_OS_WINDOWS_VISTA
```
    Is true if this is Windows Vista.
    
    The field will return false if OS_NAME is null.
    
    Since:
    
    2.4
  - IS_OS_WINDOWS_7
```
public static final boolean IS_OS_WINDOWS_7
```
    Is true if this is Windows 7.
    
    The field will return false if OS_NAME is null.
    
    Since:
    
    2.5
- Constructor Detail
  - SystemUtils
```
public SystemUtils()
```
    SystemUtils instances should NOT be constructed in standard programming. Instead, the class should be used as SystemUtils.FILE_SEPARATOR.
    
    This constructor is public to permit tools that require a JavaBean instance to operate.
- Method Detail
  - getJavaHome
```
public static File getJavaHome()
```
    Gets the Java home directory as a File.
    
    Returns:
    
    a directory
    
    Throws:
    
    SecurityException - if a security manager exists and its checkPropertyAccess method doesn't allow access to the specified system property.
    
    Since:
    
    2.1
    
    See Also:
    
    System.getProperty(String)
  - getJavaIoTmpDir
```
public static File getJavaIoTmpDir()
```
    Gets the Java IO temporary directory as a File.
    
    Returns:
    
    a directory
    
    Throws:
    
    SecurityException - if a security manager exists and its checkPropertyAccess method doesn't allow access to the specified system property.
    
    Since:
    
    2.1
    
    See Also:
    
    System.getProperty(String)
  - getJavaVersion
```
public static float getJavaVersion()
```
    Deprecated.
    Use JAVA_VERSION_FLOAT instead. Method will be removed in Commons Lang 3.0.
    Gets the Java version number as a float.
    
    Example return values:
    
    1.2f for JDK 1.2
    1.31f for JDK 1.3.1
    Returns:
    
    the version, for example 1.31f for JDK 1.3.1
  - getUserDir
```
public static File getUserDir()
```
    Gets the user directory as a File.
    
    Returns:
    
    a directory
    
    Throws:
    
    SecurityException - if a security manager exists and its checkPropertyAccess method doesn't allow access to the specified system property.
    
    Since:
    
    2.1
    
    See Also:
    
    System.getProperty(String)
  - getUserHome
```
public static File getUserHome()
```
    Gets the user home directory as a File.
    
    Returns:
    
    a directory
    
    Throws:
    
    SecurityException - if a security manager exists and its checkPropertyAccess method doesn't allow access to the specified system property.
    
    Since:
    
    2.1
    
    See Also:
    
    System.getProperty(String)
  - isJavaAwtHeadless
```
public static boolean isJavaAwtHeadless()
```
    Returns whether the JAVA_AWT_HEADLESS value is true.
    
    Returns:
    
    true if JAVA_AWT_HEADLESS is "true", false otherwise.
    
    Since:
    
    2.1, Java 1.4
    
    See Also:
    
    JAVA_AWT_HEADLESS
  - isJavaVersionAtLeast
```
public static boolean isJavaVersionAtLeast(float requiredVersion)
```
    Is the Java version at least the requested version.
    
    Example input:
    
    1.2f to test for Java 1.2
    
    1.31f to test for Java 1.3.1
    Parameters:
    
    requiredVersion - the required version, for example 1.31f
    
    Returns:
    
    true if the actual version is equal or greater than the required version
  - isJavaVersionAtLeast
```
public static boolean isJavaVersionAtLeast(int requiredVersion)
```
    Is the Java version at least the requested version.
    
    Example input:
    
    120 to test for Java 1.2 or greater
    
    131 to test for Java 1.3.1 or greater
    Parameters:
    
    requiredVersion - the required version, for example 131
    
    Returns:
    
    true if the actual version is equal or greater than the required version
    
    Since:
    
    2.0

Class SystemUtils

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

AWT_TOOLKIT

FILE_ENCODING

FILE_SEPARATOR

JAVA_AWT_FONTS

JAVA_AWT_GRAPHICSENV

JAVA_AWT_HEADLESS

JAVA_AWT_PRINTERJOB

JAVA_CLASS_PATH

JAVA_CLASS_VERSION

JAVA_COMPILER

JAVA_ENDORSED_DIRS

JAVA_EXT_DIRS

JAVA_HOME

JAVA_IO_TMPDIR

JAVA_LIBRARY_PATH

JAVA_RUNTIME_NAME

JAVA_RUNTIME_VERSION

JAVA_SPECIFICATION_NAME

JAVA_SPECIFICATION_VENDOR

JAVA_SPECIFICATION_VERSION

JAVA_UTIL_PREFS_PREFERENCES_FACTORY

JAVA_VENDOR

JAVA_VENDOR_URL

JAVA_VERSION

JAVA_VM_INFO

JAVA_VM_NAME

JAVA_VM_SPECIFICATION_NAME

JAVA_VM_SPECIFICATION_VENDOR

JAVA_VM_SPECIFICATION_VERSION

JAVA_VM_VENDOR

JAVA_VM_VERSION

LINE_SEPARATOR

OS_ARCH

OS_NAME

OS_VERSION

PATH_SEPARATOR

USER_COUNTRY

USER_DIR

USER_HOME

USER_LANGUAGE

USER_NAME

USER_TIMEZONE

JAVA_VERSION_TRIMMED

JAVA_VERSION_FLOAT

JAVA_VERSION_INT

IS_JAVA_1_1

IS_JAVA_1_2

IS_JAVA_1_3

IS_JAVA_1_4

IS_JAVA_1_5

IS_JAVA_1_6

IS_JAVA_1_7

IS_OS_AIX

IS_OS_HP_UX

IS_OS_IRIX

IS_OS_LINUX

IS_OS_MAC

IS_OS_MAC_OSX

IS_OS_OS2

IS_OS_SOLARIS

IS_OS_SUN_OS

IS_OS_UNIX

IS_OS_WINDOWS

IS_OS_WINDOWS_2000

IS_OS_WINDOWS_95

IS_OS_WINDOWS_98

IS_OS_WINDOWS_ME

IS_OS_WINDOWS_NT

IS_OS_WINDOWS_XP

IS_OS_WINDOWS_VISTA

IS_OS_WINDOWS_7

Constructor Detail

SystemUtils

Method Detail