- Direct Known Subclasses:
- RMISecurityManager
public class SecurityManager extends Object
 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.
 
 Environments using a security manager will typically set the security
 manager at startup. In the JDK implementation, this is done by setting
 the system property java.security.manager on the command line to
 the class name of the security manager. It can also be set to the empty
 String ("") or the special token "default" to use the
 default java.lang.SecurityManager. If a class name is specified,
 it must be java.lang.SecurityManager or a public subclass and have
 a public no-arg constructor. The class is loaded by the
 built-in system class loader
 if it is not java.lang.SecurityManager. If the
 java.security.manager system property is not set, the default value
 is null, which means a security manager will not be set at startup.
 
 The Java run-time may also allow, but is not required to allow, the security
 manager to be set dynamically by invoking the
 setSecurityManager method.
 In the JDK implementation, if the Java virtual machine is started with
 the java.security.manager system property set to the special token
 "disallow" then a security manager will not be set at startup and
 cannot be set dynamically (the
 setSecurityManager
 method will throw an UnsupportedOperationException). If the
 java.security.manager system property is not set or is set to the
 special token "allow", then a security manager will not be set at
 startup but can be set dynamically. Finally, if the
 java.security.manager system property is set to the class name of
 the security manager, or to the empty String ("") or the special token
 "default", then a security manager is set at startup (as described
 previously) and can also be subsequently replaced (or disabled) dynamically
 (subject to the policy of the currently installed security manager). The
 following table illustrates the behavior of the JDK implementation for the
 different settings of the java.security.manager system property:
 
| Property Value | The SecurityManager set at startup | System.setSecurityManager run-time behavior | 
|---|---|---|
| null | None | Success or throws SecurityExceptionif not permitted by
 the currently installed security manager | 
| empty String ("") | java.lang.SecurityManager | Success or throws SecurityExceptionif not permitted by
 the currently installed security manager | 
| "default" | java.lang.SecurityManager | Success or throws SecurityExceptionif not permitted by
 the currently installed security manager | 
| "disallow" | None | Always throws UnsupportedOperationException | 
| "allow" | None | Success or throws SecurityExceptionif not permitted by
 the currently installed security manager | 
| a class name | the named class | Success or throws SecurityExceptionif not permitted by
 the currently installed security manager | 
 A future release of the JDK may change the default value of the
 java.security.manager system property to "disallow".
 
 The current security manager is returned 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,- Policy,- SecurityPermission,- ProtectionDomain
- 
Constructor SummaryConstructors Constructor Description SecurityManager()Constructs a newSecurityManager.
- 
Method SummaryModifier and Type Method Description voidcheckAccept(String host, int port)Throws aSecurityExceptionif the calling thread is not permitted to accept a socket connection from the specified host and port number.voidcheckAccess(Thread t)Throws aSecurityExceptionif the calling thread is not allowed to modify the thread argument.voidcheckAccess(ThreadGroup g)Throws aSecurityExceptionif the calling thread is not allowed to modify the thread group argument.voidcheckConnect(String host, int port)Throws aSecurityExceptionif the calling thread is not allowed to open a socket connection to the specified host and port number.voidcheckConnect(String host, int port, Object context)Throws aSecurityExceptionif the specified security context is not allowed to open a socket connection to the specified host and port number.voidcheckCreateClassLoader()Throws aSecurityExceptionif the calling thread is not allowed to create a new class loader.voidcheckDelete(String file)Throws aSecurityExceptionif the calling thread is not allowed to delete the specified file.voidcheckExec(String cmd)Throws aSecurityExceptionif the calling thread is not allowed to create a subprocess.voidcheckExit(int status)Throws aSecurityExceptionif the calling thread is not allowed to cause the Java Virtual Machine to halt with the specified status code.voidcheckLink(String lib)Throws aSecurityExceptionif the calling thread is not allowed to dynamic link the library code specified by the string argument file.voidcheckListen(int port)Throws aSecurityExceptionif the calling thread is not allowed to wait for a connection request on the specified local port number.voidcheckMulticast(InetAddress maddr)Throws aSecurityExceptionif the calling thread is not allowed to use (join/leave/send/receive) IP multicast.voidcheckMulticast(InetAddress maddr, byte ttl)Deprecated.Use #checkPermission(java.security.Permission) insteadvoidcheckPackageAccess(String pkg)Throws aSecurityExceptionif the calling thread is not allowed to access the specified package.voidcheckPackageDefinition(String pkg)Throws aSecurityExceptionif the calling thread is not allowed to define classes in the specified package.voidcheckPermission(Permission perm)Throws aSecurityExceptionif the requested access, specified by the given permission, is not permitted based on the security policy currently in effect.voidcheckPermission(Permission perm, Object context)Throws aSecurityExceptionif the specified security context is denied access to the resource specified by the given permission.voidcheckPrintJobAccess()Throws aSecurityExceptionif the calling thread is not allowed to initiate a print job request.voidcheckPropertiesAccess()Throws aSecurityExceptionif the calling thread is not allowed to access or modify the system properties.voidcheckPropertyAccess(String key)Throws aSecurityExceptionif the calling thread is not allowed to access the system property with the specifiedkeyname.voidcheckRead(FileDescriptor fd)Throws aSecurityExceptionif the calling thread is not allowed to read from the specified file descriptor.voidcheckRead(String file)Throws aSecurityExceptionif the calling thread is not allowed to read the file specified by the string argument.voidcheckRead(String file, Object context)Throws aSecurityExceptionif the specified security context is not allowed to read the file specified by the string argument.voidcheckSecurityAccess(String target)Determines whether the permission with the specified permission target name should be granted or denied.voidcheckSetFactory()Throws aSecurityExceptionif the calling thread is not allowed to set the socket factory used byServerSocketorSocket, or the stream handler factory used byURL.voidcheckWrite(FileDescriptor fd)Throws aSecurityExceptionif the calling thread is not allowed to write to the specified file descriptor.voidcheckWrite(String file)Throws aSecurityExceptionif the calling thread is not allowed to write to the file specified by the string argument.protected Class<?>[]getClassContext()Returns the current execution stack as an array of classes.ObjectgetSecurityContext()Creates an object that encapsulates the current execution environment.ThreadGroupgetThreadGroup()Returns the thread group into which to instantiate any new thread being created at the time this is being called.
- 
Constructor Details- 
SecurityManagerpublic SecurityManager()Constructs a newSecurityManager.If there is a security manager already installed, this method first calls the security manager's checkPermissionmethod with theRuntimePermission("createSecurityManager")permission to ensure the calling thread has permission to create a new security manager. This may result in throwing aSecurityException.- Throws:
- SecurityException- if a security manager already exists and its- checkPermissionmethod doesn't allow creation of a new security manager.
- See Also:
- System.getSecurityManager(),- checkPermission,- RuntimePermission
 
 
- 
- 
Method Details- 
getClassContextReturns 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 0is the class of the currently executing method, the element at index1is the class of that method's caller, and so on.- Returns:
- the execution stack.
 
- 
getSecurityContextCreates an object that encapsulates the current execution environment. The result of this method is used, for example, by the three-argumentcheckConnectmethod and by the two-argumentcheckReadmethod. 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 AccessControlContextobject.- 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
 
- 
checkPermissionThrows aSecurityExceptionif the requested access, specified by the given permission, is not permitted based on the security policy currently in effect.This method calls AccessController.checkPermissionwith 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 is- null.
- Since:
- 1.2
 
- 
checkPermissionThrows aSecurityExceptionif 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 togetSecurityContextand the access control decision is based upon the configured security policy for that security context.If contextis an instance ofAccessControlContextthen theAccessControlContext.checkPermissionmethod is invoked with the specified permission.If contextis not an instance ofAccessControlContextthen aSecurityExceptionis thrown.- Parameters:
- perm- the specified permission
- context- a system-dependent security context.
- Throws:
- 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.
- Since:
- 1.2
- See Also:
- getSecurityContext(),- AccessControlContext.checkPermission(java.security.Permission)
 
- 
checkCreateClassLoaderpublic void checkCreateClassLoader()Throws aSecurityExceptionif the calling thread is not allowed to create a new class loader.This method calls checkPermissionwith theRuntimePermission("createClassLoader")permission.If you override this method, then you should make a call to super.checkCreateClassLoaderat 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
 
- 
checkAccessThrows aSecurityExceptionif 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, andsetDaemonmethods of classThread.If the thread argument is a system thread (belongs to the thread group with a nullparent) then this method callscheckPermissionwith theRuntimePermission("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.checkAccessshould 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 is- null.
- See Also:
- resume,- setDaemon,- setName,- setPriority,- stop,- suspend,- checkPermission
 
- 
checkAccessThrows aSecurityExceptionif 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, anddestroymethods of classThreadGroup.If the thread group argument is the system thread group ( has a nullparent) then this method callscheckPermissionwith theRuntimePermission("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.checkAccessshould 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 is- null.
- See Also:
- destroy,- resume,- setDaemon,- setMaxPriority,- stop,- suspend,- checkPermission
 
- 
checkExitpublic void checkExit(int status)Throws aSecurityExceptionif 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 exitmethod of classRuntime. A status of0indicates success; other values indicate various errors.This method calls checkPermissionwith theRuntimePermission("exitVM."+status)permission.If you override this method, then you should make a call to super.checkExitat 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
 
- 
checkExecThrows aSecurityExceptionif the calling thread is not allowed to create a subprocess.This method is invoked for the current security manager by the execmethods of classRuntime.This method calls checkPermissionwith theFilePermission(cmd,"execute")permission if cmd is an absolute path, otherwise it callscheckPermissionwithFilePermission("<<ALL FILES>>","execute").If you override this method, then you should make a call to super.checkExecat 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 the- cmdargument is- null.
- 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
 
- 
checkLinkThrows aSecurityExceptionif 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 loadandloadLibraryof classRuntime.This method calls checkPermissionwith theRuntimePermission("loadLibrary."+lib)permission.If you override this method, then you should make a call to super.checkLinkat 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 the- libargument is- null.
- See Also:
- Runtime.load(java.lang.String),- Runtime.loadLibrary(java.lang.String),- checkPermission
 
- 
checkReadThrows aSecurityExceptionif the calling thread is not allowed to read from the specified file descriptor.This method calls checkPermissionwith theRuntimePermission("readFileDescriptor")permission.If you override this method, then you should make a call to super.checkReadat 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 is- null.
- See Also:
- FileDescriptor,- checkPermission
 
- 
checkReadThrows aSecurityExceptionif the calling thread is not allowed to read the file specified by the string argument.This method calls checkPermissionwith theFilePermission(file,"read")permission.If you override this method, then you should make a call to super.checkReadat 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 the- fileargument is- null.
- See Also:
- checkPermission
 
- 
checkReadThrows aSecurityExceptionif 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 togetSecurityContext.If contextis an instance ofAccessControlContextthen theAccessControlContext.checkPermissionmethod will be invoked with theFilePermission(file,"read")permission.If contextis not an instance ofAccessControlContextthen aSecurityExceptionis thrown.If you override this method, then you should make a call to super.checkReadat 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 of- AccessControlContext(e.g., is- null), or does not have permission to read the specified file.
- NullPointerException- if the- fileargument is- null.
- See Also:
- getSecurityContext(),- AccessControlContext.checkPermission(java.security.Permission)
 
- 
checkWriteThrows aSecurityExceptionif the calling thread is not allowed to write to the specified file descriptor.This method calls checkPermissionwith theRuntimePermission("writeFileDescriptor")permission.If you override this method, then you should make a call to super.checkWriteat 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 is- null.
- See Also:
- FileDescriptor,- checkPermission
 
- 
checkWriteThrows aSecurityExceptionif the calling thread is not allowed to write to the file specified by the string argument.This method calls checkPermissionwith theFilePermission(file,"write")permission.If you override this method, then you should make a call to super.checkWriteat 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 the- fileargument is- null.
- See Also:
- checkPermission
 
- 
checkDeleteThrows aSecurityExceptionif the calling thread is not allowed to delete the specified file.This method is invoked for the current security manager by the deletemethod of classFile.This method calls checkPermissionwith theFilePermission(file,"delete")permission.If you override this method, then you should make a call to super.checkDeleteat 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 the- fileargument is- null.
- See Also:
- File.delete(),- checkPermission
 
- 
checkConnectThrows aSecurityExceptionif the calling thread is not allowed to open a socket connection to the specified host and port number.A port number of -1indicates that the calling method is attempting to determine the IP address of the specified host name.This method calls checkPermissionwith theSocketPermission(host+":"+port,"connect")permission if the port is not equal to -1. If the port is equal to -1, then it callscheckPermissionwith theSocketPermission(host,"resolve")permission.If you override this method, then you should make a call to super.checkConnectat 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 specified- hostand- port.
- NullPointerException- if the- hostargument is- null.
- See Also:
- checkPermission
 
- 
checkConnectThrows aSecurityExceptionif the specified security context is not allowed to open a socket connection to the specified host and port number.A port number of -1indicates that the calling method is attempting to determine the IP address of the specified host name.If contextis not an instance ofAccessControlContextthen aSecurityExceptionis thrown.Otherwise, the port number is checked. If it is not equal to -1, the context'scheckPermissionmethod is called with aSocketPermission(host+":"+port,"connect")permission. If the port is equal to -1, then thecontext'scheckPermissionmethod is called with aSocketPermission(host,"resolve")permission.If you override this method, then you should make a call to super.checkConnectat 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 of- AccessControlContext(e.g., is- null), or does not have permission to open a socket connection to the specified- hostand- port.
- NullPointerException- if the- hostargument is- null.
- See Also:
- getSecurityContext(),- AccessControlContext.checkPermission(java.security.Permission)
 
- 
checkListenpublic void checkListen(int port)Throws aSecurityExceptionif the calling thread is not allowed to wait for a connection request on the specified local port number.This method calls checkPermissionwith theSocketPermission("localhost:"+port,"listen").If you override this method, then you should make a call to super.checkListenat 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
 
- 
checkAcceptThrows aSecurityExceptionif 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 acceptmethod of classServerSocket.This method calls checkPermissionwith theSocketPermission(host+":"+port,"accept")permission.If you override this method, then you should make a call to super.checkAcceptat 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 the- hostargument is- null.
- See Also:
- ServerSocket.accept(),- checkPermission
 
- 
checkMulticastThrows aSecurityExceptionif the calling thread is not allowed to use (join/leave/send/receive) IP multicast.This method calls checkPermissionwith thejava.net.SocketPermission(maddr.getHostAddress(), "accept,connect")permission.If you override this method, then you should make a call to super.checkMulticastat 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 is- null.
- Since:
- 1.1
- See Also:
- checkPermission
 
- 
checkMulticastDeprecated.Use #checkPermission(java.security.Permission) insteadThrows aSecurityExceptionif the calling thread is not allowed to use (join/leave/send/receive) IP multicast.This method calls checkPermissionwith thejava.net.SocketPermission(maddr.getHostAddress(), "accept,connect")permission.If you override this method, then you should make a call to super.checkMulticastat 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 is- null.
- Since:
- 1.1
- See Also:
- checkPermission
 
- 
checkPropertiesAccesspublic void checkPropertiesAccess()Throws aSecurityExceptionif the calling thread is not allowed to access or modify the system properties.This method is used by the getPropertiesandsetPropertiesmethods of classSystem.This method calls checkPermissionwith thePropertyPermission("*", "read,write")permission.If you override this method, then you should make a call to super.checkPropertiesAccessat 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
 
- 
checkPropertyAccessThrows aSecurityExceptionif the calling thread is not allowed to access the system property with the specifiedkeyname.This method is used by the getPropertymethod of classSystem.This method calls checkPermissionwith thePropertyPermission(key, "read")permission.If you override this method, then you should make a call to super.checkPropertyAccessat 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 the- keyargument is- null.
- IllegalArgumentException- if- keyis empty.
- See Also:
- System.getProperty(java.lang.String),- checkPermission
 
- 
checkPrintJobAccesspublic void checkPrintJobAccess()Throws aSecurityExceptionif the calling thread is not allowed to initiate a print job request.This method calls checkPermissionwith theRuntimePermission("queuePrintJob")permission.If you override this method, then you should make a call to super.checkPrintJobAccessat 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
 
- 
checkPackageAccessThrows aSecurityExceptionif the calling thread is not allowed to access the specified package.During class loading, this method may be called by the loadClassmethod 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.accessSecurity 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 aRuntimePermission("accessClassInPackage."+pkg)permission.If this method is overridden, then super.checkPackageAccessshould 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 is- null.
- See Also:
- loadClass,- getProperty,- checkPermission
 
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checkPackageDefinitionThrows aSecurityExceptionif the calling thread is not allowed to define classes in the specified package.This method is called by the loadClassmethod of some class loaders.This method checks if the specified package starts with or equals any of the packages in the package.definitionSecurity 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 aRuntimePermission("defineClassInPackage."+pkg)permission.If this method is overridden, then super.checkPackageDefinitionshould 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 is- null.
- See Also:
- ClassLoader.loadClass(String, boolean),- getProperty,- checkPermission
 
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checkSetFactorypublic void checkSetFactory()Throws aSecurityExceptionif the calling thread is not allowed to set the socket factory used byServerSocketorSocket, or the stream handler factory used byURL.This method calls checkPermissionwith theRuntimePermission("setFactory")permission.If you override this method, then you should make a call to super.checkSetFactoryat 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
 
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checkSecurityAccessDetermines 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 SecurityPermissionobject for the given permission target name and callscheckPermissionwith it.See the documentation for SecurityPermissionIf you override this method, then you should make a call to super.checkSecurityAccessat the point the overridden method would normally throw an exception.- Parameters:
- target- the target name of the- SecurityPermission.
- Throws:
- SecurityException- if the calling thread does not have permission for the requested access.
- NullPointerException- if- targetis null.
- IllegalArgumentException- if- targetis empty.
- Since:
- 1.1
- See Also:
- checkPermission
 
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getThreadGroupReturns 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
 
 
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