Class SecurityManager
- java.lang.Object
-
- java.lang.SecurityManager
- Direct Known Subclasses:
RMISecurityManager
public class SecurityManager extends Object
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 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.
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 Java Development Kit (JDK) for permission-related information. This document includes 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 the methods that require permissions, and for each such method tells which permission it requires.
- Since:
- 1.0
- See Also:
-
ClassLoader
,SecurityException
,getSecurityManager
,setSecurityManager
,AccessController
,AccessControlContext
,AccessControlException
,Permission
,BasicPermission
,FilePermission
,SocketPermission
,PropertyPermission
,RuntimePermission
,AWTPermission
,Policy
,SecurityPermission
,ProtectionDomain
Constructor Summary
Constructor | Description |
---|---|
SecurityManager() | Constructs a new |
Method Summary
Modifier and Type | Method | Description |
---|---|---|
void | checkAccept(String host,
int port) | Throws a |
void | checkAccess(Thread t) | Throws a |
void | checkAccess(ThreadGroup g) | Throws a |
void | checkConnect(String host,
int port) | Throws a |
void | checkConnect(String host,
int port,
Object context) | Throws a |
void | checkCreateClassLoader() | Throws a |
void | checkDelete(String file) | Throws a |
void | checkExec(String cmd) | Throws a |
void | checkExit(int status) | Throws a |
void | checkLink(String lib) | Throws a |
void | checkListen(int port) | Throws a |
void | checkMulticast(InetAddress maddr) | Throws a |
void | checkMulticast(InetAddress maddr,
byte ttl) | Deprecated. Use #checkPermission(java.security.Permission) instead |
void | checkPackageAccess(String pkg) | Throws a |
void | checkPackageDefinition(String pkg) | Throws a |
void | checkPermission(Permission perm) | Throws a |
void | checkPermission(Permission perm,
Object context) | Throws a |
void | checkPrintJobAccess() | Throws a |
void | checkPropertiesAccess() | Throws a |
void | checkPropertyAccess(String key) | Throws a |
void | checkRead(FileDescriptor fd) | Throws a |
void | checkRead(String file) | Throws a |
void | checkRead(String file,
Object context) | Throws a |
void | checkSecurityAccess(String target) | Determines whether the permission with the specified permission target name should be granted or denied. |
void | checkSetFactory() | Throws a |
void | checkWrite(FileDescriptor fd) | Throws a |
void | checkWrite(String file) | Throws a |
protected Class<?>[] | getClassContext() | Returns the current execution stack as an array of classes. |
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. |
Methods declared in class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
Constructor Detail
SecurityManager
public SecurityManager()
Constructs a new 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
.
- Throws:
-
SecurityException
- if a security manager already exists and itscheckPermission
method doesn't allow creation of a new security manager. - See Also:
-
System.getSecurityManager()
,checkPermission
,RuntimePermission
Method Detail
getClassContext
protected Class<?>[] getClassContext()
Returns the current execution stack as an array of classes.
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.
- Returns:
- the execution stack.
getSecurityContext
public Object getSecurityContext()
Creates an object that encapsulates the current execution environment. The result of this method is used, for example, by the three-argument 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.
- Returns:
- an implementation-dependent object that encapsulates sufficient information about the current execution environment to perform some security checks later.
- See Also:
-
checkConnect
,checkRead
,AccessControlContext
checkPermission
public 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.
This method calls AccessController.checkPermission
with the given permission.
- Parameters:
-
perm
- the requested permission. - Throws:
-
SecurityException
- if access is not permitted based on the current security policy. -
NullPointerException
- if the permission argument isnull
. - Since:
- 1.2
checkPermission
public 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. 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.
- Parameters:
-
perm
- the specified permission -
context
- a system-dependent security context. - Throws:
-
SecurityException
- if the specified security context is not an instance ofAccessControlContext
(e.g., isnull
), or is denied access to the resource specified by the given permission. -
NullPointerException
- if the permission argument isnull
. - Since:
- 1.2
- See Also:
-
getSecurityContext()
,AccessControlContext.checkPermission(java.security.Permission)
checkCreateClassLoader
public void checkCreateClassLoader()
Throws a 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.
- Throws:
-
SecurityException
- if the calling thread does not have permission to create a new class loader. - See Also:
-
ClassLoader()
,checkPermission
checkAccess
public void checkAccess(Thread t)
Throws a 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.
- Parameters:
-
t
- the thread to be checked. - Throws:
-
SecurityException
- if the calling thread does not have permission to modify the thread. -
NullPointerException
- if the thread argument isnull
. - See Also:
-
resume
,setDaemon
,setName
,setPriority
,stop
,suspend
,checkPermission
checkAccess
public void checkAccess(ThreadGroup g)
Throws a 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.
- Parameters:
-
g
- the thread group to be checked. - Throws:
-
SecurityException
- if the calling thread does not have permission to modify the thread group. -
NullPointerException
- if the thread group argument isnull
. - See Also:
-
destroy
,resume
,setDaemon
,setMaxPriority
,stop
,suspend
,checkPermission
checkExit
public 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.
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.
- Parameters:
-
status
- the exit status. - Throws:
-
SecurityException
- if the calling thread does not have permission to halt the Java Virtual Machine with the specified status. - See Also:
-
exit
,checkPermission
checkExec
public void checkExec(String cmd)
Throws a 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.
- Parameters:
-
cmd
- the specified system command. - Throws:
-
SecurityException
- if the calling thread does not have permission to create a subprocess. -
NullPointerException
- if thecmd
argument isnull
. - See Also:
-
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
checkLink
public 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. 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.
- Parameters:
-
lib
- the name of the library. - Throws:
-
SecurityException
- if the calling thread does not have permission to dynamically link the library. -
NullPointerException
- if thelib
argument isnull
. - See Also:
-
Runtime.load(java.lang.String)
,Runtime.loadLibrary(java.lang.String)
,checkPermission
checkRead
public void checkRead(FileDescriptor fd)
Throws a 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.
- Parameters:
-
fd
- the system-dependent file descriptor. - Throws:
-
SecurityException
- if the calling thread does not have permission to access the specified file descriptor. -
NullPointerException
- if the file descriptor argument isnull
. - See Also:
-
FileDescriptor
,checkPermission
checkRead
public void checkRead(String file)
Throws a 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.
- Parameters:
-
file
- the system-dependent file name. - Throws:
-
SecurityException
- if the calling thread does not have permission to access the specified file. -
NullPointerException
- if thefile
argument isnull
. - See Also:
checkPermission
checkRead
public 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. 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.
- Parameters:
-
file
- the system-dependent filename. -
context
- a system-dependent security context. - Throws:
-
SecurityException
- if the specified security context is not an instance ofAccessControlContext
(e.g., isnull
), or does not have permission to read the specified file. -
NullPointerException
- if thefile
argument isnull
. - See Also:
-
getSecurityContext()
,AccessControlContext.checkPermission(java.security.Permission)
checkWrite
public void checkWrite(FileDescriptor fd)
Throws a 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.
- Parameters:
-
fd
- the system-dependent file descriptor. - Throws:
-
SecurityException
- if the calling thread does not have permission to access the specified file descriptor. -
NullPointerException
- if the file descriptor argument isnull
. - See Also:
-
FileDescriptor
,checkPermission
checkWrite
public void checkWrite(String file)
Throws a 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.
- Parameters:
-
file
- the system-dependent filename. - Throws:
-
SecurityException
- if the calling thread does not have permission to access the specified file. -
NullPointerException
- if thefile
argument isnull
. - See Also:
checkPermission
checkDelete
public void checkDelete(String file)
Throws a 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.
- Parameters:
-
file
- the system-dependent filename. - Throws:
-
SecurityException
- if the calling thread does not have permission to delete the file. -
NullPointerException
- if thefile
argument isnull
. - See Also:
-
File.delete()
,checkPermission
checkConnect
public 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.
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.
- Parameters:
-
host
- the host name port to connect to. -
port
- the protocol port to connect to. - Throws:
-
SecurityException
- if the calling thread does not have permission to open a socket connection to the specifiedhost
andport
. -
NullPointerException
- if thehost
argument isnull
. - See Also:
checkPermission
checkConnect
public 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.
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.
- Parameters:
-
host
- the host name port to connect to. -
port
- the protocol port to connect to. -
context
- a system-dependent security context. - Throws:
-
SecurityException
- if the specified security context is not an instance ofAccessControlContext
(e.g., isnull
), or does not have permission to open a socket connection to the specifiedhost
andport
. -
NullPointerException
- if thehost
argument isnull
. - See Also:
-
getSecurityContext()
,AccessControlContext.checkPermission(java.security.Permission)
checkListen
public 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.
This method calls checkPermission
with the SocketPermission("localhost:"+port,"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.
- Parameters:
-
port
- the local port. - Throws:
-
SecurityException
- if the calling thread does not have permission to listen on the specified port. - See Also:
checkPermission
checkAccept
public 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.
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.
- Parameters:
-
host
- the host name of the socket connection. -
port
- the port number of the socket connection. - Throws:
-
SecurityException
- if the calling thread does not have permission to accept the connection. -
NullPointerException
- if thehost
argument isnull
. - See Also:
-
ServerSocket.accept()
,checkPermission
checkMulticast
public void checkMulticast(InetAddress maddr)
Throws a 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.
- Parameters:
-
maddr
- Internet group address to be used. - Throws:
-
SecurityException
- if the calling thread is not allowed to use (join/leave/send/receive) IP multicast. -
NullPointerException
- if the address argument isnull
. - Since:
- 1.1
- See Also:
checkPermission
checkMulticast
@Deprecated(since="1.4") public void checkMulticast(InetAddress maddr, byte ttl)
Throws a 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.
- Parameters:
-
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. - Throws:
-
SecurityException
- if the calling thread is not allowed to use (join/leave/send/receive) IP multicast. -
NullPointerException
- if the address argument isnull
. - Since:
- 1.1
- See Also:
checkPermission
checkPropertiesAccess
public void checkPropertiesAccess()
Throws a 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.
- Throws:
-
SecurityException
- if the calling thread does not have permission to access or modify the system properties. - See Also:
-
System.getProperties()
,System.setProperties(java.util.Properties)
,checkPermission
checkPropertyAccess
public void checkPropertyAccess(String key)
Throws a 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.
- Parameters:
-
key
- a system property key. - Throws:
-
SecurityException
- if the calling thread does not have permission to access the specified system property. -
NullPointerException
- if thekey
argument isnull
. -
IllegalArgumentException
- ifkey
is empty. - See Also:
-
System.getProperty(java.lang.String)
,checkPermission
checkPrintJobAccess
public void checkPrintJobAccess()
Throws a 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.
- Throws:
-
SecurityException
- if the calling thread does not have permission to initiate a print job request. - Since:
- 1.1
- See Also:
checkPermission
checkPackageAccess
public void checkPackageAccess(String pkg)
Throws a SecurityException
if the calling thread is not allowed to access the specified package.
During class loading, this method may be called by the loadClass
method of class loaders and by the Java Virtual Machine to ensure that the caller is allowed to access the package of the class that is being loaded.
This method checks if the specified package starts with or equals any of the packages in the package.access
Security Property. An implementation may also check the package against an additional list of restricted packages as noted below. If the package is restricted, checkPermission(Permission)
is called with a RuntimePermission("accessClassInPackage."+pkg)
permission.
If this method is overridden, then super.checkPackageAccess
should be called as the first line in the overridden method.
- Implementation Note:
- This implementation also restricts all non-exported packages of modules loaded by the platform class loader or its ancestors. A "non-exported package" refers to a package that is not exported to all modules. Specifically, it refers to a package that either is not exported at all by its containing module or is exported in a qualified fashion by its containing module.
- Parameters:
-
pkg
- the package name. - Throws:
-
SecurityException
- if the calling thread does not have permission to access the specified package. -
NullPointerException
- if the package name argument isnull
. - See Also:
-
loadClass
,getProperty
,checkPermission
checkPackageDefinition
public void checkPackageDefinition(String pkg)
Throws a SecurityException
if the calling thread is not allowed to define classes in the specified package.
This method is called by the loadClass
method of some class loaders.
This method checks if the specified package starts with or equals any of the packages in the package.definition
Security Property. An implementation may also check the package against an additional list of restricted packages as noted below. If the package is restricted, checkPermission(Permission)
is called with a RuntimePermission("defineClassInPackage."+pkg)
permission.
If this method is overridden, then super.checkPackageDefinition
should be called as the first line in the overridden method.
- Implementation Note:
- This implementation also restricts all non-exported packages of modules loaded by the platform class loader or its ancestors. A "non-exported package" refers to a package that is not exported to all modules. Specifically, it refers to a package that either is not exported at all by its containing module or is exported in a qualified fashion by its containing module.
- Parameters:
-
pkg
- the package name. - Throws:
-
SecurityException
- if the calling thread does not have permission to define classes in the specified package. -
NullPointerException
- if the package name argument isnull
. - See Also:
-
ClassLoader.loadClass(String, boolean)
,getProperty
,checkPermission
checkSetFactory
public 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
.
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.
- Throws:
-
SecurityException
- if the calling thread does not have permission to specify a socket factory or a stream handler factory. - See Also:
-
setSocketFactory
,setSocketImplFactory
,setURLStreamHandlerFactory
,checkPermission
checkSecurityAccess
public void checkSecurityAccess(String target)
Determines whether the permission with the specified permission target name should be granted or denied.
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.
- Parameters:
-
target
- the target name of theSecurityPermission
. - Throws:
-
SecurityException
- if the calling thread does not have permission for the requested access. -
NullPointerException
- iftarget
is null. -
IllegalArgumentException
- iftarget
is empty. - Since:
- 1.1
- See Also:
checkPermission
getThreadGroup
public ThreadGroup getThreadGroup()
Returns the thread group into which to instantiate any new thread being created at the time this is being called. By default, it returns the thread group of the current thread. This should be overridden by a specific security manager to return the appropriate thread group.
- Returns:
- ThreadGroup that new threads are instantiated into
- Since:
- 1.1
- See Also:
ThreadGroup