jif.runtime
Class Runtime

java.lang.Object
  jif.runtime.Runtime

public class Runtime
extends java.lang.Object

The runtime interface between Jif programs and the underlying system.

Method Summary

static java.lang.Object[]	arrayDeepClone(java.lang.Object[] a)
static int	currentDayOfMonth(Principal dummy)
static int	currentHour(Principal dummy)
static int	currentMinute(Principal dummy)
static int	currentMonth(Principal dummy)
static java.lang.String	currentUser()
static int	currentYear(Principal dummy)
java.io.PrintStream	err() Get the standard error output parameterized by the default label, which has only one reader: the principal of this Runtime object.
static Runtime	getRuntime(Principal p) Gets a Runtime object parameterized with the principal p.
static Principal	getUser(Principal parameter, java.lang.String username) Get a native user
java.io.InputStream	in() Get the standard input parameterized by the default label, which has only one reader: the principal of this Runtime object.
java.io.FileInputStream	openFileRead(java.lang.String name, Label L) Opens a file input stream for reading from the file with the specific name.
java.io.FileOutputStream	openFileWrite(java.lang.String name, boolean append, Label L) Opens a file output stream to write a file with the specific name.
java.io.PrintStream	out() Get the standard output parameterized by the default label, which has only one reader: the principal of this Runtime object.
static void	sleep(Principal dummy, int s)
java.io.PrintStream	stderr(Label l) Gets the standard error output.
java.io.InputStream	stdin(Label l) Gets the standard input.
java.io.PrintStream	stdout(Label l) Gets the standard output.
static Principal	user(Principal parameter) Get the current user

Methods inherited from class java.lang.Object

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

Method Detail

getRuntime

public static Runtime getRuntime(Principal p)
                          throws java.lang.SecurityException

Gets a Runtime object parameterized with the principal p.

Throws:

java.lang.SecurityException

user

public static Principal user(Principal parameter)

Get the current user

getUser

public static Principal getUser(Principal parameter,
                                java.lang.String username)

Get a native user

openFileWrite

public java.io.FileOutputStream openFileWrite(java.lang.String name,
                                              boolean append,
                                              Label L)
                                       throws java.io.IOException,
                                              java.lang.SecurityException

Opens a file output stream to write a file with the specific name.

Parameters:

name - the file name

append - if true, then bytes will be written to the end of the file rather than the beginning

L - the label parameter of the resulting FileOutputStream

Throws:

java.io.FileNotFoundException - if the file exists but is a directory rather than a regular file, does not exist but cannot be created, or cannot be opened for any other reason.

java.lang.SecurityException - if l is unable to relabel to the Jif label derived from the ACL of the file.

java.io.IOException

openFileRead

public java.io.FileInputStream openFileRead(java.lang.String name,
                                            Label L)
                                     throws java.io.FileNotFoundException,
                                            java.lang.SecurityException

Opens a file input stream for reading from the file with the specific name.

Parameters:

name - the file name

L - the the label parameter of the resulting FileInputStream

Throws:

java.lang.SecurityException - if l is less restrictive than the Jif label derived from the ACL of the file.

java.io.FileNotFoundException

stderr

public java.io.PrintStream stderr(Label l)

Gets the standard error output. The output channel is parameterized by l.

stdout

public java.io.PrintStream stdout(Label l)

Gets the standard output. This output channel is parameterized by l.

stdin

public java.io.InputStream stdin(Label l)

Gets the standard input. This input channel is parameterized by l.

out

public java.io.PrintStream out()

Get the standard output parameterized by the default label, which has only one reader: the principal of this Runtime object.

in

public java.io.InputStream in()

Get the standard input parameterized by the default label, which has only one reader: the principal of this Runtime object.

err

public java.io.PrintStream err()

Get the standard error output parameterized by the default label, which has only one reader: the principal of this Runtime object.

currentUser

public static java.lang.String currentUser()

currentYear

public static int currentYear(Principal dummy)

currentMonth

public static int currentMonth(Principal dummy)

currentDayOfMonth

public static int currentDayOfMonth(Principal dummy)

currentHour

public static int currentHour(Principal dummy)

currentMinute

public static int currentMinute(Principal dummy)

sleep

public static void sleep(Principal dummy,
                         int s)

arrayDeepClone

public static java.lang.Object[] arrayDeepClone(java.lang.Object[] a)