[JAVA API] java.lang.System

java.lang

Class System

• java.lang.Object
• • java.lang.System

• ---

  
  

  public final class System
  extends Object

  The System class contains several useful class fields and methods. It cannot be instantiated.

  Among the facilities provided by the System class are standard input, standard output, and error output streams; access to externally defined properties and environment variables; a means of loading files and libraries; and a utility method for quickly copying a portion of an array.

  Since:

  JDK1.0

• • Field Summary

    Fields 

    Modifier and Type	Field and Description
    static PrintStream	err The "standard" error output stream.
    static InputStream	in The "standard" input stream.
    static PrintStream	out The "standard" output stream.

  • Method Summary

    Methods 

    Modifier and Type	Method and Description
    static void	arraycopy(Object src, int srcPos, Object dest, int destPos, int length) Copies an array from the specified source array, beginning at the specified position, to the specified position of the destination array.
    static String	clearProperty(String key) Removes the system property indicated by the specified key.
    static Console	console() Returns the unique Console object associated with the current Java virtual machine, if any.
    static long	currentTimeMillis() Returns the current time in milliseconds.
    static void	exit(int status) Terminates the currently running Java Virtual Machine.
    static void	gc() Runs the garbage collector.
    static Map<String,String>	getenv() Returns an unmodifiable string map view of the current system environment.
    static String	getenv(String name) Gets the value of the specified environment variable.
    static Properties	getProperties() Determines the current system properties.
    static String	getProperty(String key) Gets the system property indicated by the specified key.
    static String	getProperty(String key, String def) Gets the system property indicated by the specified key.
    static SecurityManager	getSecurityManager() Gets the system security interface.
    static int	identityHashCode(Object x) Returns the same hash code for the given object as would be returned by the default method hashCode(), whether or not the given object's class overrides hashCode().
    static Channel	inheritedChannel() Returns the channel inherited from the entity that created this Java virtual machine.
    static String	lineSeparator() Returns the system-dependent line separator string.
    static void	load(String filename) Loads a code file with the specified filename from the local file system as a dynamic library.
    static void	loadLibrary(String libname) Loads the system library specified by the libname argument.
    static String	mapLibraryName(String libname) Maps a library name into a platform-specific string representing a native library.
    static long	nanoTime() Returns the current value of the running Java Virtual Machine's high-resolution time source, in nanoseconds.
    static void	runFinalization() Runs the finalization methods of any objects pending finalization.
    static void	runFinalizersOnExit(boolean value) Deprecated.  This method is inherently unsafe. It may result in finalizers being called on live objects while other threads are concurrently manipulating those objects, resulting in erratic behavior or deadlock.
    static void	setErr(PrintStream err) Reassigns the "standard" error output stream.
    static void	setIn(InputStream in) Reassigns the "standard" input stream.
    static void	setOut(PrintStream out) Reassigns the "standard" output stream.
    static void	setProperties(Properties props) Sets the system properties to the Properties argument.
    static String	setProperty(String key, String value) Sets the system property indicated by the specified key.
    static void	setSecurityManager(SecurityManager s) Sets the System security.

    • Methods inherited from class java.lang.Object

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