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## java.lang
Class RuntimePermission

    java.lang.Object
      |
      +--java.security.Permission
            |
            +--java.security.BasicPermission
                  |
                  +--java.lang.RuntimePermission

All Implemented Interfaces:
  Guard, Serializable

public final class RuntimePermission
extends BasicPermission

This class is for runtime permissions. A RuntimePermission contains a name (also referred to as a "target name") but no actions list; you either have the named permission or you don't.

The target name is the name of the runtime permission (see below). The naming convention follows the hierarchical property naming convention. Also, an asterisk may appear at the end of the name, following a ".", or by itself, to signify a wildcard match. For example: "loadLibrary.*" or "*" is valid, "*loadLibrary" or "a*b" is not valid.

The following table lists all the possible RuntimePermission target names, and for each provides a description of what the permission allows and a discussion of the risks of granting code the permission.

Permission Target Name | What the Permission Allows | Risks of Allowing this Permission
--- | --- | ---
createClassLoader | Creation of a class loader | This is an extremely dangerous permission to grant. Malicious applications that can instantiate their own class loaders could then load their own rogue classes into the system. These newly loaded classes could be placed into any protection domain by the class loader, thereby automatically granting the classes the permissions for that domain.
getClassLoader | Retrieval of a class loader (e.g., the class loader for the calling class) | This would grant an attacker permission to get the class loader for a particular class. This is dangerous because having access to a class's class loader allows the attacker to load other classes available to that class loader. The attacker would typically otherwise not have access to those classes.
setContextClassLoader | Setting of the context class loader used by a thread | The context class loader is used by system code and extensions when they need to lookup resources that might not exist in the system class loader. Granting setContextClassLoader permission would allow code to change which context class loader is used for a particular thread, including system threads.
setSecurityManager | Setting of the security manager (possibly replacing an existing one) | The security manager is a class that allows applications to implement a security policy. Granting the setSecurityManager permission would allow code to change which security manager is used by installing a different, possibly less restrictive security manager, thereby bypassing checks that would have been enforced by the original security manager.
createSecurityManager | Creation of a new security manager | This gives code access to protected, sensitive methods that may disclose information about other classes or the execution stack.
exitVM | Halting of the Java Virtual Machine | This allows an attacker to mount a denial-of-service attack by automatically forcing the virtual machine to halt. Note: The "exitVM" permission is automatically granted to all code loaded from the application class path, thus enabling applications to terminate themselves.
shutdownHooks | Registration and cancellation of virtual-machine shutdown hooks | This allows an attacker to register a malicious shutdown hook that interferes with the clean shutdown of the virtual machine.
setFactory | Setting of the socket factory used by ServerSocket or Socket, or of the stream handler factory used by URL | This allows code to set the actual implementation for the socket, server socket, stream handler, or RMI socket factory. An attacker may set a faulty implementation which mangles the data stream.
setIO | Setting of System.out, System.in, and System.err | This allows changing the value of the standard system streams. An attacker may change System.in to monitor and steal user input, or may set System.err to a "null" OutputSteam, which would hide any error messages sent to System.err.
modifyThread | Modification of threads, e.g., via calls to Thread `stop`, `suspend`, `resume`, `setPriority`, and `setName` methods | This allows an attacker to start or suspend any thread in the system.
stopThread | Stopping of threads via calls to the Thread `stop` method | This allows code to stop any thread in the system provided that it is already granted permission to access that thread. This poses as a threat, because that code may corrupt the system by killing existing threads.
modifyThreadGroup | modification of thread groups, e.g., via calls to ThreadGroup `destroy`, `getParent`, `resume`, `setDaemon`, `setMaxPriority`, `stop`, and `suspend` methods | This allows an attacker to create thread groups and set their run priority.
getProtectionDomain | Retrieval of the ProtectionDomain for a class | This allows code to obtain policy information for a particular code source. While obtaining policy information does not compromise the security of the system, it does give attackers additional information, such as local file names for example, to better aim an attack.
readFileDescriptor | Reading of file descriptors | This would allow code to read the particular file associated with the file descriptor read. This is dangerous if the file contains confidential data.
writeFileDescriptor | Writing to file descriptors | This allows code to write to a particular file associated with the descriptor. This is dangerous because it may allow malicious code to plant viruses or at the very least, fill up your entire disk.
loadLibrary.{library name} | Dynamic linking of the specified library | It is dangerous to allow an applet permission to load native code libraries, because the Java security architecture is not designed to and does not prevent malicious behavior at the level of native code.
accessClassInPackage.{package name} | Access to the specified package via a class loader's `loadClass` method when that class loader calls the SecurityManager `checkPackageAcesss` method | This gives code access to classes in packages to which it normally does not have access. Malicious code may use these classes to help in its attempt to compromise security in the system.
defineClassInPackage.{package name} | Definition of classes in the specified package, via a class loader's `defineClass` method when that class loader calls the SecurityManager `checkPackageDefinition` method. | This grants code permission to define a class in a particular package. This is dangerous because malicious code with this permission may define rogue classes in trusted packages like `java.security` or `java.lang`, for example.
accessDeclaredMembers | Access to the declared members of a class | This grants code permission to query a class for its public, protected, default (package) access, and private fields and/or methods. Although the code would have access to the private and protected field and method names, it would not have access to the private/protected field data and would not be able to invoke any private methods. Nevertheless, malicious code may use this information to better aim an attack. Additionally, it may invoke any public methods and/or access public fields in the class. This could be dangerous if the code would normally not be able to invoke those methods and/or access the fields because it can't cast the object to the class/interface with those methods and fields.
queuePrintJob | Initiation of a print job request | This could print sensitive information to a printer, or simply waste paper.

See Also:
  `BasicPermission`, `Permission`, `Permissions`, `PermissionCollection`, `SecurityManager`, Serialized Form

Constructor Summary
`RuntimePermission(String name)` Creates a new RuntimePermission with the specified name.
`RuntimePermission(String name, String actions)` Creates a new RuntimePermission object with the specified name.

Methods inherited from class java.security.BasicPermission
`equals, getActions, hashCode, implies, newPermissionCollection`

Methods inherited from class java.security.Permission
`checkGuard, getName, toString`

Methods inherited from class java.lang.Object
`clone, finalize, getClass, notify, notifyAll, wait, wait, wait`

Constructor Detail

### RuntimePermission

    public RuntimePermission(String name)

  Creates a new RuntimePermission with the specified name. The name is the symbolic name of the RuntimePermission, such as "exit", "setFactory", etc. An asterisk may appear at the end of the name, following a ".", or by itself, to signify a wildcard match.

Parameters:
  `name` - the name of the RuntimePermission.

### RuntimePermission

    public RuntimePermission(String name,
                             String actions)

  Creates a new RuntimePermission object with the specified name. The name is the symbolic name of the RuntimePermission, and the actions String is currently unused and should be null.

Parameters:
  `name` - the name of the RuntimePermission.
  `actions` - should be null.

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For further API reference and developer documentation, see Java 2 SDK SE Developer Documentation. That documentation contains more detailed, developer-targeted descriptions, with conceptual overviews, definitions of terms, workarounds, and working code examples.

Copyright 2002 Sun Microsystems, Inc. All rights reserved. Use is subject to license terms.