Package org.refcodes.runtime

Class SystemUtility

java.lang.Object

org.refcodes.runtime.SystemUtility

public final class SystemUtility
extends java.lang.Object

Utility for acquiring system information on the machine this process is running in.

Method Summary

Modifier and Type	Method	Description
static java.lang.String	exec(int aTimeOutMillis, java.lang.String aCommandLine)	Executes a command and returns the output.
static java.lang.String	exec(int aTimeOutMillis, java.lang.String... aCommandLine)	Executes a command and returns the output.
static java.lang.String	exec(java.lang.String aCommandLine)	Executes a command and returns the output.
static java.lang.String	exec(java.lang.String... aCommandLine)	Executes a command and returns the output.
static java.lang.String	getComputerName()	Determines the computer's name.
static java.lang.String	getUname()	If on a *nix alike system, this method returns the output of the "uname -a" command: "uname" prints system information, "-a" instructs it to print all information.
static byte[]	toHostIpAddress()	Tries to determine a no-localhost IP-Address for this machine.
static byte[]	toHostMacAddress()	Tries to determine the host Mac-Address for this machine.
static java.lang.String	toPrettySystemInfo()	Gathers all available system information from this Artifac's point of view.
static java.lang.String	toPropertyValue(java.lang.String aDefaultValue, org.refcodes.data.SystemProperty aSystemProperty, org.refcodes.data.EnvironmentVariable... aEnvironmentProperties)	Gets the value for the provided properties, if non was found then the default value is taken.
static java.lang.String	toPropertyValue(org.refcodes.data.SystemProperty aSystemProperty, org.refcodes.data.EnvironmentVariable... aEnvironmentProperties)	Gets the value for the provided properties, if non was found then null is returned.
static java.util.Map<java.lang.String,java.lang.String>	toSystemInfo()	Gathers all available system information from this Artifac's point of view.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Detail

getComputerName

public static java.lang.String getComputerName()

Determines the computer's name. First it tries to get it from the InetAddress, if it fails it tries to get it from the system's environment using the EnvironmentVariable.COMPUTERNAME (on Windows machines only) and if both fails, it returns the default Literal.LOCALHOST identifier.

Returns:

The computer's name, as fallback, Literal.LOCALHOST ("localhost") is returned.

getUname

public static java.lang.String getUname()

If on a *nix alike system, this method returns the output of the "uname -a" command: "uname" prints system information, "-a" instructs it to print all information.

Returns:

The "uname -a" output or null if "uname" is not known.

toPropertyValue

public static java.lang.String toPropertyValue(java.lang.String aDefaultValue,
                                               org.refcodes.data.SystemProperty aSystemProperty,
                                               org.refcodes.data.EnvironmentVariable... aEnvironmentProperties)

Gets the value for the provided properties, if non was found then the default value is taken. A SystemProperty elements wins over the EnvironmentVariable elements. The preceding EnvironmentVariable element wins over the succeeding EnvironmentVariable element. The default value is taken if non property had a value (a String with length > 0).

Parameters:

aDefaultValue - The default value to take when none other value was set.

aSystemProperty - The system-property passed via java -D<name>=<value>

aEnvironmentProperties - The properties looked for in the system's environment variables.

Returns:

The best fitting value.

toPropertyValue

public static java.lang.String toPropertyValue(org.refcodes.data.SystemProperty aSystemProperty,
                                               org.refcodes.data.EnvironmentVariable... aEnvironmentProperties)

Gets the value for the provided properties, if non was found then null is returned. A SystemProperty elements wins over the EnvironmentVariable elements. The preceding EnvironmentVariable element wins over the succeeding EnvironmentVariable element. A null is taken if non property had a value (a String with length > 0).

Parameters:

aSystemProperty - The system-property passed via java -D<name>=<value>

aEnvironmentProperties - The properties looked for in the system's environment variables.

Returns:

The best fitting value or null if none was detected.

exec

public static java.lang.String exec(int aTimeOutMillis,
                                    java.lang.String aCommandLine)
                             throws java.io.IOException,
                                    java.lang.InterruptedException

Executes a command and returns the output.

Parameters:

aTimeOutMillis - The time in milliseconds to wait till the process is killed when not terminated yet.

aCommandLine - the command

Returns:

Null if execution failed, else the according output. An empty String stands fur successful execution.

Throws:

java.io.IOException - in case there were problems executing the command.

java.lang.InterruptedException - thrown in case execution as been interrupted.

exec

public static java.lang.String exec(int aTimeOutMillis,
                                    java.lang.String... aCommandLine)
                             throws java.io.IOException,
                                    java.lang.InterruptedException

Executes a command and returns the output.

Parameters:

aTimeOutMillis - The time in milliseconds to wait till the process is killed when not terminated yet.

aCommandLine - the command with the arguments to be passed to the command.

Returns:

Null if execution failed, else the according output. An empty String stands fur successful execution.

Throws:

java.io.IOException - in case there were problems executing the command.

java.lang.InterruptedException - thrown in case execution as been interrupted.

exec

public static java.lang.String exec(java.lang.String aCommandLine)
                             throws java.io.IOException

Executes a command and returns the output.

Parameters:

aCommandLine - the command

Returns:

Null if execution failed, else the according output. An empty String stands fur successful execution.

Throws:

java.io.IOException - in case there were problems executing the command.

exec

public static java.lang.String exec(java.lang.String... aCommandLine)
                             throws java.io.IOException

Executes a command and returns the output.

Parameters:

aCommandLine - the command with the arguments to be passed to the command.

Returns:

Null if execution failed, else the according output. An empty String stands fur successful execution.

Throws:

java.io.IOException - in case there were problems executing the command.

toSystemInfo

public static java.util.Map<java.lang.String,java.lang.String> toSystemInfo()

Gathers all available system information from this Artifac's point of view.

Returns:

A Map containing the available information being gathered.

toPrettySystemInfo

public static java.lang.String toPrettySystemInfo()

Gathers all available system information from this Artifac's point of view. This method may rely on the output of toSystemInfo().

Returns:

A String containing the available information being gathered.

toHostIpAddress

public static byte[] toHostIpAddress()
                              throws java.net.SocketException,
                                     java.net.UnknownHostException

Tries to determine a no-localhost IP-Address for this machine. The best guess is returned. If none no-localhost address is found, then the localhost's IP-Address may be returned (as of InetAddress.getLocalHost()).

Returns:

The best guest for a no-localhost IP-Address or as a fall back the localhost's IP-Address (as of InetAddress.getLocalHost() may be returned.

Throws:

java.net.SocketException - Thrown to indicate that accessing the network interfaces caused a problem.

java.net.UnknownHostException - Thrown to indicate that the IP address of the local host could not be determined.

toHostMacAddress

public static byte[] toHostMacAddress()
                               throws java.net.SocketException,
                                      java.net.UnknownHostException

Tries to determine the host Mac-Address for this machine. The best guess is returned.

Returns:

The best guest for a Mac-Address is returned.

Throws:

java.net.SocketException - Thrown to indicate that accessing the network interfaces caused a problem.

java.net.UnknownHostException - Thrown to indicate that the IP address of the local host could not be determined.