Module xaos.core

Package eu.ess.xaos.core.util

Class SystemUtils

java.lang.Object

eu.ess.xaos.core.util.SystemUtils

public class SystemUtils
extends Object

Some system utilities.

Author:

claudio.rosati@esss.se

Method Summary

Modifier and Type	Method	Description
static ProcessBuilder	build(Class<?> clazz, List<String> jvmArgs, List<String> args)	Creates a ProcessBuilder ready to execute the given class (that needs to have a main method) as a detached sub-process.
static ProcessBuilder	build(String module, Class<?> clazz, List<String> jvmArgs, List<String> args)	Creates a ProcessBuilder ready to execute the given class (that needs to have a main method) as a detached sub-process.
static String	execute(File workingDirectory, String... command)	Execute the given command and return its output as a string.
static int	execute(Class<?> clazz, List<String> jvmArgs, List<String> args)	Executes the given class (that needs to have a main method) as a detached sub-process, returning its exit value.
static String	execute(String... command)	Execute the given command and return its output as a string.
static int	execute(String module, Class<?> clazz, List<String> jvmArgs, List<String> args)	Executes the given class (that needs to have a main method) as a detached sub-process, returning its exit value.
static double	freeDiskSpace(File path)	Returns the percentage of available space to this virtual machine on the partition named by the given abstract pathname.

Methods inherited from class java.lang.Object

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

Method Detail

build

public static ProcessBuilder build(Class<?> clazz,
                                   List<String> jvmArgs,
                                   List<String> args)

Creates a ProcessBuilder ready to execute the given class (that needs to have a main method) as a detached sub-process. Current class-path will be used to find the given class and its dependencies.

Parameters:

clazz - The class to be executed.

jvmArgs - The JVM arguments.

args - The class arguments.

Returns:

The ProcessBuilder ready to run the given class.

See Also:

Running a Java Class as a Subprocess

build

public static ProcessBuilder build(String module,
                                   Class<?> clazz,
                                   List<String> jvmArgs,
                                   List<String> args)

Creates a ProcessBuilder ready to execute the given class (that needs to have a main method) as a detached sub-process. Current module-path will be used to find the given module and class and its dependencies.

Parameters:

module - The name of the module containing the class to be executed.

clazz - The class to be executed.

jvmArgs - The JVM arguments.

args - The class arguments.

Returns:

The ProcessBuilder ready to run the given class.

execute

public static String execute(String... command)

Execute the given command and return its output as a string.

Parameters:

command - The command (and parameters) to be executed.

Returns:

The output from the executed process.

execute

public static String execute(File workingDirectory,
                             String... command)

Execute the given command and return its output as a string.

Parameters:

workingDirectory - The directory where the execution must be performed. Can be null to inherit the working directory from the current process.

command - The command (and parameters) to be executed.

Returns:

The output from the executed process, or null if an exception was thrown (and logged).

execute

public static int execute(Class<?> clazz,
                          List<String> jvmArgs,
                          List<String> args)
                   throws IOException,
                          InterruptedException

Executes the given class (that needs to have a main method) as a detached sub-process, returning its exit value. Current class-path will be used to find the given class and its dependencies. Standard input and output will be the same of the calling application.

Parameters:

clazz - The class to be executed.

jvmArgs - The JVM arguments.

args - The class arguments.

Returns:

The class execution exist status.

Throws:

IOException - If an I/O error occurs.

InterruptedException - If the execution is interrupted.

See Also:

Running a Java Class as a Subprocess

execute

public static int execute(String module,
                          Class<?> clazz,
                          List<String> jvmArgs,
                          List<String> args)
                   throws IOException,
                          InterruptedException

Executes the given class (that needs to have a main method) as a detached sub-process, returning its exit value. Current module-path will be used to find the given module and class and its dependencies. Standard input and output will be the same of the calling application.

Parameters:

module - The name of the module containing the class to be executed.

clazz - The class to be executed.

jvmArgs - The JVM arguments.

args - The class arguments.

Returns:

The class execution exist status.

Throws:

IOException - If an I/O error occurs.

InterruptedException - If the execution is interrupted.

freeDiskSpace

public static double freeDiskSpace(File path)

Returns the percentage of available space to this virtual machine on the partition named by the given abstract pathname.

Parameters:

path - A file identifying the partition to be queried.

Returns:

The percentage of available space to this virtual machine, as a double in the [0.0, 1.0] range.