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 -

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 -

since: Java - 1.2

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

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 -

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 -

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.

Also see:

isJavaAwtHeadless()
since: 2.1 -

since: Java - 1.4

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 -

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

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

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.

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

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

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

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

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

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 -

since: Java - 1.3

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 -

since: Java - 1.3

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

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

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

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 -

since: Java - 1.4

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

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

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

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 -

since: Java - 1.2

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

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

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

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

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

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

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

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

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

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

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

The user.country or user.region System Property. User's country code, such as GB. First in JDK 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 -

since: Java - 1.2

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

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

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 -

since: Java - 1.2

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

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 -

Gets the Java version as a String trimming leading letters.

The field will return null if #JAVA_VERSION is null.

since: 2.1 -

Gets the Java version as a float.

Example return values:

• 1.2f for JDK 1.2
• 1.31f for JDK 1.3.1

The field will return zero if #JAVA_VERSION is null.

since: 2.0 -

Gets the Java version as an int.

Example return values:

• 120 for JDK 1.2
• 131 for JDK 1.3.1

The field will return zero if #JAVA_VERSION is null.

since: 2.0 -

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 true if this is Java version 1.2 (also 1.2.x versions).

The field will return false if #JAVA_VERSION is null.

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 true if this is Java version 1.4 (also 1.4.x versions).

The field will return false if #JAVA_VERSION is null.

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 true if this is Java version 1.6 (also 1.6.x versions).

The field will return false if #JAVA_VERSION is null.

Is true if this is AIX.

The field will return false if OS_NAME is null.

since: 2.0 -

Is true if this is HP-UX.

The field will return false if OS_NAME is null.

since: 2.0 -

Is true if this is Irix.

The field will return false if OS_NAME is null.

since: 2.0 -

Is true if this is Linux.

The field will return false if OS_NAME is null.

since: 2.0 -

Is true if this is Mac.

The field will return false if OS_NAME is null.

since: 2.0 -

Is true if this is Mac.

The field will return false if OS_NAME is null.

since: 2.0 -

Is true if this is OS/2.

The field will return false if OS_NAME is null.

since: 2.0 -

Is true if this is Solaris.

The field will return false if OS_NAME is null.

since: 2.0 -

Is true if this is SunOS.

The field will return false if OS_NAME is null.

since: 2.0 -

Is true if this is a POSIX compilant 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 true if this is Windows.

The field will return false if OS_NAME is null.

since: 2.0 -

Is true if this is Windows 2000.

The field will return false if OS_NAME is null.

since: 2.0 -

Is true if this is Windows 95.

The field will return false if OS_NAME is null.

since: 2.0 -

Is true if this is Windows 98.

The field will return false if OS_NAME is null.

since: 2.0 -

Is true if this is Windows ME.

The field will return false if OS_NAME is null.

since: 2.0 -

Is true if this is Windows NT.

The field will return false if OS_NAME is null.

since: 2.0 -

Is true if this is Windows XP.

The field will return false if OS_NAME is null.

since: 2.0 -

 public SystemUtils() 
{
        super();
}

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.

 public static File getJavaHome() 
{
        return new File(System.getProperty(JAVA_HOME_KEY));
}

Gets the Java home directory as a File.

 public static File getJavaIoTmpDir() 
{
        return new File(System.getProperty(JAVA_IO_TMPDIR_KEY));
}

Gets the Java IO temporary directory as a File.

 public static float getJavaVersion() 
{
        return JAVA_VERSION_FLOAT;
}

Gets the Java version number as a float.

Example return values:

• 1.2f for JDK 1.2
• 1.31f for JDK 1.3.1

 public static File getUserDir() 
{
        return new File(System.getProperty(USER_DIR_KEY));
}

Gets the user directory as a File.

 public static File getUserHome() 
{
        return new File(System.getProperty(USER_HOME_KEY));
}

Gets the user home directory as a File.

 public static boolean isJavaAwtHeadless() 
{
        return JAVA_AWT_HEADLESS != null ? JAVA_AWT_HEADLESS.equals(Boolean.TRUE.toString()) : false;
}

Returns whether the #JAVA_AWT_HEADLESS value is true.

 public static boolean isJavaVersionAtLeast(float requiredVersion) 
{
        return JAVA_VERSION_FLOAT  >= requiredVersion;
}

Is the Java version at least the requested version.

Example input:

• 1.2f to test for JDK 1.2
• 1.31f to test for JDK 1.3.1

 public static boolean isJavaVersionAtLeast(int requiredVersion) 
{
        return JAVA_VERSION_INT  >= requiredVersion;
}

Is the Java version at least the requested version.

Example input:

• 120 to test for JDK 1.2 or greater
• 131 to test for JDK 1.3.1 or greater