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Java™ Platform Standard Ed. 6 |
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java.lang.Object java.lang.SecurityManager
public class SecurityManager
The security manager is a class that allows applications to implement a security policy. It allows an application to determine, before performing a possibly unsafe or sensitive operation, what the operation is and whether it is being attempted in a security context that allows the operation to be performed. The application can allow or disallow the operation.
The SecurityManager
class contains many methods with
names that begin with the word check
. These methods
are called by various methods in the Java libraries before those
methods perform certain potentially sensitive operations. The
invocation of such a check
method typically looks like this:
SecurityManager security = System.getSecurityManager(); if (security != null) { security.checkXXX(argument, . . . ); }
The security manager is thereby given an opportunity to prevent
completion of the operation by throwing an exception. A security
manager routine simply returns if the operation is permitted, but
throws a SecurityException
if the operation is not
permitted. The only exception to this convention is
checkTopLevelWindow
, which returns a
boolean
value.
The current security manager is set by the
setSecurityManager
method in class
System
. The current security manager is obtained
by the getSecurityManager
method.
The special method
checkPermission(java.security.Permission)
determines whether an access request indicated by a specified
permission should be granted or denied. The
default implementation calls
AccessController.checkPermission(perm);
If a requested access is allowed,
checkPermission
returns quietly. If denied, a
SecurityException
is thrown.
As of Java 2 SDK v1.2, the default implementation of each of the other
check
methods in SecurityManager
is to
call the SecurityManager checkPermission
method
to determine if the calling thread has permission to perform the requested
operation.
Note that the checkPermission
method with
just a single permission argument always performs security checks
within the context of the currently executing thread.
Sometimes a security check that should be made within a given context
will actually need to be done from within a
different context (for example, from within a worker thread).
The getSecurityContext
method
and the checkPermission
method that includes a context argument are provided
for this situation. The
getSecurityContext
method returns a "snapshot"
of the current calling context. (The default implementation
returns an AccessControlContext object.) A sample call is
the following:
Object context = null; SecurityManager sm = System.getSecurityManager(); if (sm != null) context = sm.getSecurityContext();
The checkPermission
method
that takes a context object in addition to a permission
makes access decisions based on that context,
rather than on that of the current execution thread.
Code within a different context can thus call that method,
passing the permission and the
previously-saved context object. A sample call, using the
SecurityManager sm
obtained as in the previous example,
is the following:
if (sm != null) sm.checkPermission(permission, context);
Permissions fall into these categories: File, Socket, Net,
Security, Runtime, Property, AWT, Reflect, and Serializable.
The classes managing these various
permission categories are java.io.FilePermission
,
java.net.SocketPermission
,
java.net.NetPermission
,
java.security.SecurityPermission
,
java.lang.RuntimePermission
,
java.util.PropertyPermission
,
java.awt.AWTPermission
,
java.lang.reflect.ReflectPermission
, and
java.io.SerializablePermission
.
All but the first two (FilePermission and SocketPermission) are
subclasses of java.security.BasicPermission
, which itself
is an abstract subclass of the
top-level class for permissions, which is
java.security.Permission
. BasicPermission defines the
functionality needed for all permissions that contain a name
that follows the hierarchical property naming convention
(for example, "exitVM", "setFactory", "queuePrintJob", etc).
An asterisk
may appear at the end of the name, following a ".", or by itself, to
signify a wildcard match. For example: "a.*" or "*" is valid,
"*a" or "a*b" is not valid.
FilePermission and SocketPermission are subclasses of the
top-level class for permissions
(java.security.Permission
). Classes like these
that have a more complicated name syntax than that used by
BasicPermission subclass directly from Permission rather than from
BasicPermission. For example,
for a java.io.FilePermission
object, the permission name is
the path name of a file (or directory).
Some of the permission classes have an "actions" list that tells
the actions that are permitted for the object. For example,
for a java.io.FilePermission
object, the actions list
(such as "read, write") specifies which actions are granted for the
specified file (or for files in the specified directory).
Other permission classes are for "named" permissions - ones that contain a name but no actions list; you either have the named permission or you don't.
Note: There is also a java.security.AllPermission
permission that implies all permissions. It exists to simplify the work
of system administrators who might need to perform multiple
tasks that require all (or numerous) permissions.
See
Permissions in the JDK for permission-related information.
This document includes, for example, a table listing the various SecurityManager
check
methods and the permission(s) the default
implementation of each such method requires.
It also contains a table of all the version 1.2 methods
that require permissions, and for each such method tells
which permission it requires.
For more information about SecurityManager
changes made in
the JDK and advice regarding porting of 1.1-style security managers,
see the security documentation.
ClassLoader
,
SecurityException
,
checkTopLevelWindow
,
getSecurityManager
,
setSecurityManager
,
AccessController
,
AccessControlContext
,
AccessControlException
,
Permission
,
BasicPermission
,
FilePermission
,
SocketPermission
,
PropertyPermission
,
RuntimePermission
,
AWTPermission
,
Policy
,
SecurityPermission
,
ProtectionDomain
Field Summary | |
---|---|
protected boolean |
inCheck
Deprecated. This type of security checking is not recommended. It is recommended that the checkPermission
call be used instead. |
Constructor Summary | |
---|---|
SecurityManager()
Constructs a new SecurityManager . |
Method Summary | |
---|---|
void |
checkAccept(String host,
int port)
Throws a SecurityException if the
calling thread is not permitted to accept a socket connection from
the specified host and port number. |
void |
checkAccess(Thread t)
Throws a SecurityException if the
calling thread is not allowed to modify the thread argument. |
void |
checkAccess(ThreadGroup g)
Throws a SecurityException if the
calling thread is not allowed to modify the thread group argument. |
void |
checkAwtEventQueueAccess()
Throws a SecurityException if the
calling thread is not allowed to access the AWT event queue. |
void |
checkConnect(String host,
int port)
Throws a SecurityException if the
calling thread is not allowed to open a socket connection to the
specified host and port number. |
void |
checkConnect(String host,
int port,
Object context)
Throws a SecurityException if the
specified security context is not allowed to open a socket
connection to the specified host and port number. |
void |
checkCreateClassLoader()
Throws a SecurityException if the
calling thread is not allowed to create a new class loader. |
void |
checkDelete(String file)
Throws a SecurityException if the
calling thread is not allowed to delete the specified file. |
void |
checkExec(String cmd)
Throws a SecurityException if the
calling thread is not allowed to create a subprocess. |
void |
checkExit(int status)
Throws a SecurityException if the
calling thread is not allowed to cause the Java Virtual Machine to
halt with the specified status code. |
void |
checkLink(String lib)
Throws a SecurityException if the
calling thread is not allowed to dynamic link the library code
specified by the string argument file. |
void |
checkListen(int port)
Throws a SecurityException if the
calling thread is not allowed to wait for a connection request on
the specified local port number. |
void |
checkMemberAccess(Class<?> clazz,
int which)
Throws a SecurityException if the
calling thread is not allowed to access members. |
void |
checkMulticast(InetAddress maddr)
Throws a SecurityException if the
calling thread is not allowed to use
(join/leave/send/receive) IP multicast. |
void |
checkMulticast(InetAddress maddr,
byte ttl)
Deprecated. Use #checkPermission(java.security.Permission) instead |
void |
checkPackageAccess(String pkg)
Throws a SecurityException if the
calling thread is not allowed to access the package specified by
the argument. |
void |
checkPackageDefinition(String pkg)
Throws a SecurityException if the
calling thread is not allowed to define classes in the package
specified by the argument. |
void |
checkPermission(Permission perm)
Throws a SecurityException if the requested
access, specified by the given permission, is not permitted based
on the security policy currently in effect. |
void |
checkPermission(Permission perm,
Object context)
Throws a SecurityException if the
specified security context is denied access to the resource
specified by the given permission. |
void |
checkPrintJobAccess()
Throws a SecurityException if the
calling thread is not allowed to initiate a print job request. |
void |
checkPropertiesAccess()
Throws a SecurityException if the
calling thread is not allowed to access or modify the system
properties. |
void |
checkPropertyAccess(String key)
Throws a SecurityException if the
calling thread is not allowed to access the system property with
the specified key name. |
void |
checkRead(FileDescriptor fd)
Throws a SecurityException if the
calling thread is not allowed to read from the specified file
descriptor. |
void |
checkRead(String file)
Throws a SecurityException if the
calling thread is not allowed to read the file specified by the
string argument. |
void |
checkRead(String file,
Object context)
Throws a SecurityException if the
specified security context is not allowed to read the file
specified by the string argument. |
void |
checkSecurityAccess(String target)
Determines whether the permission with the specified permission target name should be granted or denied. |
void |
checkSetFactory()
Throws a SecurityException if the
calling thread is not allowed to set the socket factory used by
ServerSocket or Socket , or the stream
handler factory used by URL . |
void |
checkSystemClipboardAccess()
Throws a SecurityException if the
calling thread is not allowed to access the system clipboard. |
boolean |
checkTopLevelWindow(Object window)
Returns false if the calling
thread is not trusted to bring up the top-level window indicated
by the window argument. |
void |
checkWrite(FileDescriptor fd)
Throws a SecurityException if the
calling thread is not allowed to write to the specified file
descriptor. |
void |
checkWrite(String file)
Throws a SecurityException if the
calling thread is not allowed to write to the file specified by
the string argument. |
protected int |
classDepth(String name)
Deprecated. This type of security checking is not recommended. It is recommended that the checkPermission
call be used instead. |
protected int |
classLoaderDepth()
Deprecated. This type of security checking is not recommended. It is recommended that the checkPermission
call be used instead. |
protected ClassLoader |
currentClassLoader()
Deprecated. This type of security checking is not recommended. It is recommended that the checkPermission
call be used instead. |
protected Class<?> |
currentLoadedClass()
Deprecated. This type of security checking is not recommended. It is recommended that the checkPermission
call be used instead. |
protected Class[] |
getClassContext()
Returns the current execution stack as an array of classes. |
boolean |
getInCheck()
Deprecated. This type of security checking is not recommended. It is recommended that the checkPermission
call be used instead. |
Object |
getSecurityContext()
Creates an object that encapsulates the current execution environment. |
ThreadGroup |
getThreadGroup()
Returns the thread group into which to instantiate any new thread being created at the time this is being called. |
protected boolean |
inClass(String name)
Deprecated. This type of security checking is not recommended. It is recommended that the checkPermission
call be used instead. |
protected boolean |
inClassLoader()
Deprecated. This type of security checking is not recommended. It is recommended that the checkPermission
call be used instead. |
Methods inherited from class java.lang.Object |
---|
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait |
Field Detail |
---|
@Deprecated protected boolean inCheck
checkPermission
call be used instead.true
if there is a security check in
progress; false
otherwise.
Constructor Detail |
---|
public SecurityManager()
SecurityManager
.
If there is a security manager already installed, this method first
calls the security manager's checkPermission
method
with the RuntimePermission("createSecurityManager")
permission to ensure the calling thread has permission to create a new
security manager.
This may result in throwing a SecurityException
.
SecurityException
- if a security manager already
exists and its checkPermission
method
doesn't allow creation of a new security manager.System.getSecurityManager()
,
checkPermission
,
RuntimePermission
Method Detail |
---|
@Deprecated public boolean getInCheck()
checkPermission
call be used instead.
inCheck
field. This field
should contain true
if a security check is
in progress,
false
otherwise.inCheck
protected Class[] getClassContext()
The length of the array is the number of methods on the execution
stack. The element at index 0
is the class of the
currently executing method, the element at index 1
is
the class of that method's caller, and so on.
@Deprecated protected ClassLoader currentClassLoader()
checkPermission
call be used instead.
ClassLoader.getSystemClassLoader()
) or one of its ancestors.
This method will return
null
in the following three cases:
AccessController.doPrivileged(java.security.PrivilegedAction)
)
are from classes
defined using the system class loader or one of its ancestors.
checkPermission
with
java.security.AllPermission
does not
result in a SecurityException.
getSystemClassLoader
,
checkPermission
@Deprecated protected Class<?> currentLoadedClass()
checkPermission
call be used instead.
ClassLoader.getSystemClassLoader()
) or one of its ancestors.
This method will return
null
in the following three cases:
AccessController.doPrivileged(java.security.PrivilegedAction)
)
are from classes
defined using the system class loader or one of its ancestors.
checkPermission
with
java.security.AllPermission
does not
result in a SecurityException.
getSystemClassLoader
,
checkPermission
@Deprecated protected int classDepth(String name)
checkPermission
call be used instead.
name
- the fully qualified name of the class to search for.
-1
if such a frame cannot be found.@Deprecated protected int classLoaderDepth()
checkPermission
call be used instead.
ClassLoader.getSystemClassLoader()
) or one of its ancestors.
This method will return -1 in the following three cases:
AccessController.doPrivileged(java.security.PrivilegedAction)
)
are from classes
defined using the system class loader or one of its ancestors.
checkPermission
with
java.security.AllPermission
does not
result in a SecurityException.
getSystemClassLoader
,
checkPermission
@Deprecated protected boolean inClass(String name)
checkPermission
call be used instead.
name
- the fully qualified name of the class.
true
if a method from a class with the specified
name is on the execution stack; false
otherwise.@Deprecated protected boolean inClassLoader()
checkPermission
call be used instead.
true
if a call to currentClassLoader
has a non-null return value.currentClassLoader
public Object getSecurityContext()
checkConnect
method and by the
two-argument checkRead
method.
These methods are needed because a trusted method may be called
on to read a file or open a socket on behalf of another method.
The trusted method needs to determine if the other (possibly
untrusted) method would be allowed to perform the operation on its
own.
The default implementation of this method is to return
an AccessControlContext
object.
checkConnect
,
checkRead
,
AccessControlContext
public void checkPermission(Permission perm)
SecurityException
if the requested
access, specified by the given permission, is not permitted based
on the security policy currently in effect.
This method calls AccessController.checkPermission
with the given permission.
perm
- the requested permission.
SecurityException
- if access is not permitted based on
the current security policy.
NullPointerException
- if the permission argument is
null
.public void checkPermission(Permission perm, Object context)
SecurityException
if the
specified security context is denied access to the resource
specified by the given permission.
The context must be a security
context returned by a previous call to
getSecurityContext
and the access control
decision is based upon the configured security policy for
that security context.
If context
is an instance of
AccessControlContext
then the
AccessControlContext.checkPermission
method is
invoked with the specified permission.
If context
is not an instance of
AccessControlContext
then a
SecurityException
is thrown.
perm
- the specified permissioncontext
- a system-dependent security context.
SecurityException
- if the specified security context
is not an instance of AccessControlContext
(e.g., is null
), or is denied access to the
resource specified by the given permission.
NullPointerException
- if the permission argument is
null
.getSecurityContext()
,
AccessControlContext.checkPermission(java.security.Permission)
public void checkCreateClassLoader()
SecurityException
if the
calling thread is not allowed to create a new class loader.
This method calls checkPermission
with the
RuntimePermission("createClassLoader")
permission.
If you override this method, then you should make a call to
super.checkCreateClassLoader
at the point the overridden method would normally throw an
exception.
SecurityException
- if the calling thread does not
have permission
to create a new class loader.ClassLoader.ClassLoader()
,
checkPermission
public void checkAccess(Thread t)
SecurityException
if the
calling thread is not allowed to modify the thread argument.
This method is invoked for the current security manager by the
stop
, suspend
, resume
,
setPriority
, setName
, and
setDaemon
methods of class Thread
.
If the thread argument is a system thread (belongs to
the thread group with a null
parent) then
this method calls checkPermission
with the
RuntimePermission("modifyThread")
permission.
If the thread argument is not a system thread,
this method just returns silently.
Applications that want a stricter policy should override this
method. If this method is overridden, the method that overrides
it should additionally check to see if the calling thread has the
RuntimePermission("modifyThread")
permission, and
if so, return silently. This is to ensure that code granted
that permission (such as the JDK itself) is allowed to
manipulate any thread.
If this method is overridden, then
super.checkAccess
should
be called by the first statement in the overridden method, or the
equivalent security check should be placed in the overridden method.
t
- the thread to be checked.
SecurityException
- if the calling thread does not have
permission to modify the thread.
NullPointerException
- if the thread argument is
null
.resume
,
setDaemon
,
setName
,
setPriority
,
stop
,
suspend
,
checkPermission
public void checkAccess(ThreadGroup g)
SecurityException
if the
calling thread is not allowed to modify the thread group argument.
This method is invoked for the current security manager when a
new child thread or child thread group is created, and by the
setDaemon
, setMaxPriority
,
stop
, suspend
, resume
, and
destroy
methods of class ThreadGroup
.
If the thread group argument is the system thread group (
has a null
parent) then
this method calls checkPermission
with the
RuntimePermission("modifyThreadGroup")
permission.
If the thread group argument is not the system thread group,
this method just returns silently.
Applications that want a stricter policy should override this
method. If this method is overridden, the method that overrides
it should additionally check to see if the calling thread has the
RuntimePermission("modifyThreadGroup")
permission, and
if so, return silently. This is to ensure that code granted
that permission (such as the JDK itself) is allowed to
manipulate any thread.
If this method is overridden, then
super.checkAccess
should
be called by the first statement in the overridden method, or the
equivalent security check should be placed in the overridden method.
g
- the thread group to be checked.
SecurityException
- if the calling thread does not have
permission to modify the thread group.
NullPointerException
- if the thread group argument is
null
.destroy
,
resume
,
setDaemon
,
setMaxPriority
,
stop
,
suspend
,
checkPermission
public void checkExit(int status)
SecurityException
if the
calling thread is not allowed to cause the Java Virtual Machine to
halt with the specified status code.
This method is invoked for the current security manager by the
exit
method of class Runtime
. A status
of 0
indicates success; other values indicate various
errors.
This method calls checkPermission
with the
RuntimePermission("exitVM."+status)
permission.
If you override this method, then you should make a call to
super.checkExit
at the point the overridden method would normally throw an
exception.
status
- the exit status.
SecurityException
- if the calling thread does not have
permission to halt the Java Virtual Machine with
the specified status.exit
,
checkPermission
public void checkExec(String cmd)
SecurityException
if the
calling thread is not allowed to create a subprocess.
This method is invoked for the current security manager by the
exec
methods of class Runtime
.
This method calls checkPermission
with the
FilePermission(cmd,"execute")
permission
if cmd is an absolute path, otherwise it calls
checkPermission
with
FilePermission("<<ALL FILES>>","execute")
.
If you override this method, then you should make a call to
super.checkExec
at the point the overridden method would normally throw an
exception.
cmd
- the specified system command.
SecurityException
- if the calling thread does not have
permission to create a subprocess.
NullPointerException
- if the cmd
argument is
null
.Runtime.exec(java.lang.String)
,
Runtime.exec(java.lang.String, java.lang.String[])
,
Runtime.exec(java.lang.String[])
,
Runtime.exec(java.lang.String[], java.lang.String[])
,
checkPermission
public void checkLink(String lib)
SecurityException
if the
calling thread is not allowed to dynamic link the library code
specified by the string argument file. The argument is either a
simple library name or a complete filename.
This method is invoked for the current security manager by
methods load
and loadLibrary
of class
Runtime
.
This method calls checkPermission
with the
RuntimePermission("loadLibrary."+lib)
permission.
If you override this method, then you should make a call to
super.checkLink
at the point the overridden method would normally throw an
exception.
lib
- the name of the library.
SecurityException
- if the calling thread does not have
permission to dynamically link the library.
NullPointerException
- if the lib
argument is
null
.Runtime.load(java.lang.String)
,
Runtime.loadLibrary(java.lang.String)
,
checkPermission
public void checkRead(FileDescriptor fd)
SecurityException
if the
calling thread is not allowed to read from the specified file
descriptor.
This method calls checkPermission
with the
RuntimePermission("readFileDescriptor")
permission.
If you override this method, then you should make a call to
super.checkRead
at the point the overridden method would normally throw an
exception.
fd
- the system-dependent file descriptor.
SecurityException
- if the calling thread does not have
permission to access the specified file descriptor.
NullPointerException
- if the file descriptor argument is
null
.FileDescriptor
,
checkPermission
public void checkRead(String file)
SecurityException
if the
calling thread is not allowed to read the file specified by the
string argument.
This method calls checkPermission
with the
FilePermission(file,"read")
permission.
If you override this method, then you should make a call to
super.checkRead
at the point the overridden method would normally throw an
exception.
file
- the system-dependent file name.
SecurityException
- if the calling thread does not have
permission to access the specified file.
NullPointerException
- if the file
argument is
null
.checkPermission
public void checkRead(String file, Object context)
SecurityException
if the
specified security context is not allowed to read the file
specified by the string argument. The context must be a security
context returned by a previous call to
getSecurityContext
.
If context
is an instance of
AccessControlContext
then the
AccessControlContext.checkPermission
method will
be invoked with the FilePermission(file,"read")
permission.
If context
is not an instance of
AccessControlContext
then a
SecurityException
is thrown.
If you override this method, then you should make a call to
super.checkRead
at the point the overridden method would normally throw an
exception.
file
- the system-dependent filename.context
- a system-dependent security context.
SecurityException
- if the specified security context
is not an instance of AccessControlContext
(e.g., is null
), or does not have permission
to read the specified file.
NullPointerException
- if the file
argument is
null
.getSecurityContext()
,
AccessControlContext.checkPermission(java.security.Permission)
public void checkWrite(FileDescriptor fd)
SecurityException
if the
calling thread is not allowed to write to the specified file
descriptor.
This method calls checkPermission
with the
RuntimePermission("writeFileDescriptor")
permission.
If you override this method, then you should make a call to
super.checkWrite
at the point the overridden method would normally throw an
exception.
fd
- the system-dependent file descriptor.
SecurityException
- if the calling thread does not have
permission to access the specified file descriptor.
NullPointerException
- if the file descriptor argument is
null
.FileDescriptor
,
checkPermission
public void checkWrite(String file)
SecurityException
if the
calling thread is not allowed to write to the file specified by
the string argument.
This method calls checkPermission
with the
FilePermission(file,"write")
permission.
If you override this method, then you should make a call to
super.checkWrite
at the point the overridden method would normally throw an
exception.
file
- the system-dependent filename.
SecurityException
- if the calling thread does not
have permission to access the specified file.
NullPointerException
- if the file
argument is
null
.checkPermission
public void checkDelete(String file)
SecurityException
if the
calling thread is not allowed to delete the specified file.
This method is invoked for the current security manager by the
delete
method of class File
.
This method calls checkPermission
with the
FilePermission(file,"delete")
permission.
If you override this method, then you should make a call to
super.checkDelete
at the point the overridden method would normally throw an
exception.
file
- the system-dependent filename.
SecurityException
- if the calling thread does not
have permission to delete the file.
NullPointerException
- if the file
argument is
null
.File.delete()
,
checkPermission
public void checkConnect(String host, int port)
SecurityException
if the
calling thread is not allowed to open a socket connection to the
specified host and port number.
A port number of -1
indicates that the calling
method is attempting to determine the IP address of the specified
host name.
This method calls checkPermission
with the
SocketPermission(host+":"+port,"connect")
permission if
the port is not equal to -1. If the port is equal to -1, then
it calls checkPermission
with the
SocketPermission(host,"resolve")
permission.
If you override this method, then you should make a call to
super.checkConnect
at the point the overridden method would normally throw an
exception.
host
- the host name port to connect to.port
- the protocol port to connect to.
SecurityException
- if the calling thread does not have
permission to open a socket connection to the specified
host
and port
.
NullPointerException
- if the host
argument is
null
.checkPermission
public void checkConnect(String host, int port, Object context)
SecurityException
if the
specified security context is not allowed to open a socket
connection to the specified host and port number.
A port number of -1
indicates that the calling
method is attempting to determine the IP address of the specified
host name.
If context
is not an instance of
AccessControlContext
then a
SecurityException
is thrown.
Otherwise, the port number is checked. If it is not equal
to -1, the context
's checkPermission
method is called with a
SocketPermission(host+":"+port,"connect")
permission.
If the port is equal to -1, then
the context
's checkPermission
method
is called with a
SocketPermission(host,"resolve")
permission.
If you override this method, then you should make a call to
super.checkConnect
at the point the overridden method would normally throw an
exception.
host
- the host name port to connect to.port
- the protocol port to connect to.context
- a system-dependent security context.
SecurityException
- if the specified security context
is not an instance of AccessControlContext
(e.g., is null
), or does not have permission
to open a socket connection to the specified
host
and port
.
NullPointerException
- if the host
argument is
null
.getSecurityContext()
,
AccessControlContext.checkPermission(java.security.Permission)
public void checkListen(int port)
SecurityException
if the
calling thread is not allowed to wait for a connection request on
the specified local port number.
If port is not 0, this method calls
checkPermission
with the
SocketPermission("localhost:"+port,"listen")
.
If port is zero, this method calls checkPermission
with SocketPermission("localhost:1024-","listen").
If you override this method, then you should make a call to
super.checkListen
at the point the overridden method would normally throw an
exception.
port
- the local port.
SecurityException
- if the calling thread does not have
permission to listen on the specified port.checkPermission
public void checkAccept(String host, int port)
SecurityException
if the
calling thread is not permitted to accept a socket connection from
the specified host and port number.
This method is invoked for the current security manager by the
accept
method of class ServerSocket
.
This method calls checkPermission
with the
SocketPermission(host+":"+port,"accept")
permission.
If you override this method, then you should make a call to
super.checkAccept
at the point the overridden method would normally throw an
exception.
host
- the host name of the socket connection.port
- the port number of the socket connection.
SecurityException
- if the calling thread does not have
permission to accept the connection.
NullPointerException
- if the host
argument is
null
.ServerSocket.accept()
,
checkPermission
public void checkMulticast(InetAddress maddr)
SecurityException
if the
calling thread is not allowed to use
(join/leave/send/receive) IP multicast.
This method calls checkPermission
with the
java.net.SocketPermission(maddr.getHostAddress(),
"accept,connect")
permission.
If you override this method, then you should make a call to
super.checkMulticast
at the point the overridden method would normally throw an
exception.
maddr
- Internet group address to be used.
SecurityException
- if the calling thread is not allowed to
use (join/leave/send/receive) IP multicast.
NullPointerException
- if the address argument is
null
.checkPermission
@Deprecated public void checkMulticast(InetAddress maddr, byte ttl)
SecurityException
if the
calling thread is not allowed to use
(join/leave/send/receive) IP multicast.
This method calls checkPermission
with the
java.net.SocketPermission(maddr.getHostAddress(),
"accept,connect")
permission.
If you override this method, then you should make a call to
super.checkMulticast
at the point the overridden method would normally throw an
exception.
maddr
- Internet group address to be used.ttl
- value in use, if it is multicast send.
Note: this particular implementation does not use the ttl
parameter.
SecurityException
- if the calling thread is not allowed to
use (join/leave/send/receive) IP multicast.
NullPointerException
- if the address argument is
null
.checkPermission
public void checkPropertiesAccess()
SecurityException
if the
calling thread is not allowed to access or modify the system
properties.
This method is used by the getProperties
and
setProperties
methods of class System
.
This method calls checkPermission
with the
PropertyPermission("*", "read,write")
permission.
If you override this method, then you should make a call to
super.checkPropertiesAccess
at the point the overridden method would normally throw an
exception.
SecurityException
- if the calling thread does not have
permission to access or modify the system properties.System.getProperties()
,
System.setProperties(java.util.Properties)
,
checkPermission
public void checkPropertyAccess(String key)
SecurityException
if the
calling thread is not allowed to access the system property with
the specified key
name.
This method is used by the getProperty
method of
class System
.
This method calls checkPermission
with the
PropertyPermission(key, "read")
permission.
If you override this method, then you should make a call to
super.checkPropertyAccess
at the point the overridden method would normally throw an
exception.
key
- a system property key.
SecurityException
- if the calling thread does not have
permission to access the specified system property.
NullPointerException
- if the key
argument is
null
.
IllegalArgumentException
- if key
is empty.System.getProperty(java.lang.String)
,
checkPermission
public boolean checkTopLevelWindow(Object window)
false
if the calling
thread is not trusted to bring up the top-level window indicated
by the window
argument. In this case, the caller can
still decide to show the window, but the window should include
some sort of visual warning. If the method returns
true
, then the window can be shown without any
special restrictions.
See class Window
for more information on trusted and
untrusted windows.
This method calls
checkPermission
with the
AWTPermission("showWindowWithoutWarningBanner")
permission,
and returns true
if a SecurityException is not thrown,
otherwise it returns false
.
If you override this method, then you should make a call to
super.checkTopLevelWindow
at the point the overridden method would normally return
false
, and the value of
super.checkTopLevelWindow
should
be returned.
window
- the new window that is being created.
true
if the calling thread is trusted to put up
top-level windows; false
otherwise.
NullPointerException
- if the window
argument is
null
.Window
,
checkPermission
public void checkPrintJobAccess()
SecurityException
if the
calling thread is not allowed to initiate a print job request.
This method calls
checkPermission
with the
RuntimePermission("queuePrintJob")
permission.
If you override this method, then you should make a call to
super.checkPrintJobAccess
at the point the overridden method would normally throw an
exception.
SecurityException
- if the calling thread does not have
permission to initiate a print job request.checkPermission
public void checkSystemClipboardAccess()
SecurityException
if the
calling thread is not allowed to access the system clipboard.
This method calls checkPermission
with the
AWTPermission("accessClipboard")
permission.
If you override this method, then you should make a call to
super.checkSystemClipboardAccess
at the point the overridden method would normally throw an
exception.
SecurityException
- if the calling thread does not have
permission to access the system clipboard.checkPermission
public void checkAwtEventQueueAccess()
SecurityException
if the
calling thread is not allowed to access the AWT event queue.
This method calls checkPermission
with the
AWTPermission("accessEventQueue")
permission.
If you override this method, then you should make a call to
super.checkAwtEventQueueAccess
at the point the overridden method would normally throw an
exception.
SecurityException
- if the calling thread does not have
permission to access the AWT event queue.checkPermission
public void checkPackageAccess(String pkg)
SecurityException
if the
calling thread is not allowed to access the package specified by
the argument.
This method is used by the loadClass
method of class
loaders.
This method first gets a list of
restricted packages by obtaining a comma-separated list from
a call to
java.security.Security.getProperty("package.access")
,
and checks to see if pkg
starts with or equals
any of the restricted packages. If it does, then
checkPermission
gets called with the
RuntimePermission("accessClassInPackage."+pkg)
permission.
If this method is overridden, then
super.checkPackageAccess
should be called
as the first line in the overridden method.
pkg
- the package name.
SecurityException
- if the calling thread does not have
permission to access the specified package.
NullPointerException
- if the package name argument is
null
.loadClass
,
getProperty
,
checkPermission
public void checkPackageDefinition(String pkg)
SecurityException
if the
calling thread is not allowed to define classes in the package
specified by the argument.
This method is used by the loadClass
method of some
class loaders.
This method first gets a list of restricted packages by
obtaining a comma-separated list from a call to
java.security.Security.getProperty("package.definition")
,
and checks to see if pkg
starts with or equals
any of the restricted packages. If it does, then
checkPermission
gets called with the
RuntimePermission("defineClassInPackage."+pkg)
permission.
If this method is overridden, then
super.checkPackageDefinition
should be called
as the first line in the overridden method.
pkg
- the package name.
SecurityException
- if the calling thread does not have
permission to define classes in the specified package.ClassLoader.loadClass(java.lang.String, boolean)
,
getProperty
,
checkPermission
public void checkSetFactory()
SecurityException
if the
calling thread is not allowed to set the socket factory used by
ServerSocket
or Socket
, or the stream
handler factory used by URL
.
This method calls checkPermission
with the
RuntimePermission("setFactory")
permission.
If you override this method, then you should make a call to
super.checkSetFactory
at the point the overridden method would normally throw an
exception.
SecurityException
- if the calling thread does not have
permission to specify a socket factory or a stream
handler factory.setSocketFactory
,
setSocketImplFactory
,
setURLStreamHandlerFactory
,
checkPermission
public void checkMemberAccess(Class<?> clazz, int which)
SecurityException
if the
calling thread is not allowed to access members.
The default policy is to allow access to PUBLIC members, as well
as access to classes that have the same class loader as the caller.
In all other cases, this method calls checkPermission
with the RuntimePermission("accessDeclaredMembers")
permission.
If this method is overridden, then a call to
super.checkMemberAccess
cannot be made,
as the default implementation of checkMemberAccess
relies on the code being checked being at a stack depth of
4.
clazz
- the class that reflection is to be performed on.which
- type of access, PUBLIC or DECLARED.
SecurityException
- if the caller does not have
permission to access members.
NullPointerException
- if the clazz
argument is
null
.Member
,
checkPermission
public void checkSecurityAccess(String target)
If the requested permission is allowed, this method returns quietly. If denied, a SecurityException is raised.
This method creates a SecurityPermission
object for
the given permission target name and calls checkPermission
with it.
See the documentation for
for
a list of possible permission target names.
SecurityPermission
If you override this method, then you should make a call to
super.checkSecurityAccess
at the point the overridden method would normally throw an
exception.
target
- the target name of the SecurityPermission
.
SecurityException
- if the calling thread does not have
permission for the requested access.
NullPointerException
- if target
is null.
IllegalArgumentException
- if target
is empty.checkPermission
public ThreadGroup getThreadGroup()
ThreadGroup
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