THE PACKAGE JAVA.LANG

java.lang.ThreadGroup

20.21

20.21.4

public final void checkAccess()

If there is a security manager, its

checkAccess

 method ( 20.17.12) is called with

this

ThreadGroup

 object as its argument. This may result in throwing, in the cur 

rent thread, a

SecurityException

.

This method is called by methods

stop

 ( 20.21.8),

suspend

 ( 20.21.9),

resume

 ( 20.21.10),

destroy

 ( 20.21.11),

setMaxPriority

 ( 20.21.13), and

setDaemon

 ( 20.21.15).

20.21.5

public final String getName()

The current name of this

ThreadGroup

 object is returned as a

String

.

20.21.6

public final ThreadGroup getParent()

This method returns the

ThreadGroup

 object that represents the thread group to

which this thread group belongs. If this thread group is the system thread group,

which is at the root of the thread group hierarchy, then

null

 is returned.

20.21.7

public final boolean parentOf(ThreadGroup g)

This method returns

true

 if and only if either this thread group is

g

 or this method

is

true

 when applied to the parent of

g

. In other words, this method says whether

this thread group is an ancestor of

g

 or perhaps

g

 itself.

(This method arguably is misnamed; a more accurate, if clumsy and abstruse,

name would be

parentOfReflexiveTransitiveClosure

.)

20.21.8

public final void stop() throws SecurityException

First, the

checkAccess

 method ( 20.21.4) of this

ThreadGroup

 object is called

with no arguments. This may result in a

SecurityException

 being thrown (in

the current thread).

Every thread in this thread group or any of its subgroups is stopped. More

precisely, the method

stop

 is called for every

ThreadGroup

 and every

Thread

( 20.20.15) that belongs to this

ThreadGroup

.

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