com.sun.jini.start

Class LoaderSplitPolicyProvider

java.lang.Object

java.security.Policy

com.sun.jini.start.LoaderSplitPolicyProvider

All Implemented Interfaces:

DynamicPolicy

public class LoaderSplitPolicyProvider
extends Policy
implements DynamicPolicy

Security policy provider which handles permission queries and grants by delegating to different policy providers depending on the class loader involved. Each LoaderSplitPolicyProvider instance wraps two underlying policy providers:

• a class-loader specific policy provider, consulted for permission queries/grants pertaining to that class loader, any child class loaders that delegate to it, or the null class loader, and
• a default policy provider, consulted for all other operations (aside from refresh(), which applies to both policies).

Since:

2.0

Author:

Sun Microsystems, Inc.

Nested Class Summary

Nested classes/interfaces inherited from class java.security.Policy

Policy.Parameters

Field Summary

Fields inherited from class java.security.Policy

UNSUPPORTED_EMPTY_COLLECTION

Constructor Summary

Constructors

Constructor and Description

LoaderSplitPolicyProvider(ClassLoader loader, Policy loaderPolicy, Policy defaultPolicy) Creates a new LoaderSplitPolicyProvider instance which delegates to loaderPolicy any permission query/grant operations involving protection domains or classes with the given class loader, any child class loader of the given class loader, or the null class loader; all other operations are delegated to defaultPolicy (with the exception of refresh, which applies to both policies).

Method Summary

Modifier and Type	Method and Description
Permission[]	getGrants(Class cl, Principal[] principals) If both underlying policy providers support dynamic grants, delegates to the getGrants method of the underlying policy associated with the loader of the given class (the loader-specific policy if the class loader is null, the same as or a child of the loader specified in the constructor for this instance, or the default loader otherwise).
PermissionCollection	getPermissions(CodeSource source) Delegates to the corresponding getPermissions method of the underlying default policy.
PermissionCollection	getPermissions(ProtectionDomain domain) If the given protection domain is the protection domain of this class, then a newly-created PermissionCollection containing AllPermission is returned.
void	grant(Class cl, Principal[] principals, Permission[] permissions) If both underlying policy providers support dynamic grants, delegates to the grant method of the underlying policy associated with the loader of the given class (the loader-specific policy if the class loader is null, the same as or a child of the loader specified in the constructor for this instance, or the default loader otherwise).
boolean	grantSupported() Returns true if both of the underlying policy providers implement DynamicPolicy and return true from calls to grantSupported; returns false otherwise.
boolean	implies(ProtectionDomain domain, Permission permission) If the given protection domain is the protection domain of this class, then true is returned.
void	refresh() Invokes refresh on both the loader-specific and default underlying policy providers.

Methods inherited from class java.security.Policy

getInstance, getInstance, getInstance, getParameters, getPolicy, getProvider, getType, setPolicy

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

LoaderSplitPolicyProvider

public LoaderSplitPolicyProvider(ClassLoader loader,
                                 Policy loaderPolicy,
                                 Policy defaultPolicy)

Creates a new LoaderSplitPolicyProvider instance which delegates to loaderPolicy any permission query/grant operations involving protection domains or classes with the given class loader, any child class loader of the given class loader, or the null class loader; all other operations are delegated to defaultPolicy (with the exception of refresh, which applies to both policies).

Parameters:

loader - class loader for which associated permission query/grant operations should be forwarded to loaderPolicy

loaderPolicy - class loader-specific security policy provider

defaultPolicy - default security policy provider

Throws:

NullPointerException - if loader, loaderPolicy or defaultPolicy is null

Method Detail

getPermissions

public PermissionCollection getPermissions(CodeSource source)

Delegates to the corresponding getPermissions method of the underlying default policy.

Overrides:

getPermissions in class Policy

Parameters:

source - code source for which to look up permissions

Returns:

set of permissions allowed for the given code source

getPermissions

public PermissionCollection getPermissions(ProtectionDomain domain)

If the given protection domain is the protection domain of this class, then a newly-created PermissionCollection containing AllPermission is returned. If not, delegates to the corresponding getPermissions method of the underlying policy associated with the loader of the given class (the loader-specific policy if the class loader is null, the same as or a child of the loader specified in the constructor for this instance, or the default loader otherwise).

Overrides:

getPermissions in class Policy

Parameters:

domain - protection domain for which to look up permissions

Returns:

set of permissions allowed for given protection domain

implies

public boolean implies(ProtectionDomain domain,
                       Permission permission)

If the given protection domain is the protection domain of this class, then true is returned. If not, delegates to the implies method of the underlying policy associated with the loader of the given class (the loader-specific policy if the class loader is null, the same as or a child of the loader specified in the constructor for this instance, or the default loader otherwise).

Overrides:

implies in class Policy

Parameters:

domain - protection domain in which to check implication

permission - permission to test implication of

Returns:

true if permission is implied by permissions of given protection domain, false otherwise

refresh

public void refresh()

Invokes refresh on both the loader-specific and default underlying policy providers.

Overrides:

refresh in class Policy

grantSupported

public boolean grantSupported()

Returns true if both of the underlying policy providers implement DynamicPolicy and return true from calls to grantSupported; returns false otherwise.

Specified by:

grantSupported in interface DynamicPolicy

Returns:

true if policy supports dynamic permission grants under current context, false otherwise

grant

public void grant(Class cl,
                  Principal[] principals,
                  Permission[] permissions)

If both underlying policy providers support dynamic grants, delegates to the grant method of the underlying policy associated with the loader of the given class (the loader-specific policy if the class loader is null, the same as or a child of the loader specified in the constructor for this instance, or the default loader otherwise). If at least one of the underlying policy providers does not support dynamic grants, throws an UnsupportedOperationException.

Specified by:

grant in interface DynamicPolicy

Parameters:

cl - class to grant permissions to the class loader of, or null if granting across all class loaders

principals - if non-null, minimum set of principals to which grants apply

permissions - if non-null, permissions to grant

Throws:

UnsupportedOperationException - if policy does not support dynamic grants, or if cl is non-null and belongs to a protection domain with a null class loader other than the system domain

SecurityException - if a security manager is installed and the calling context does not have sufficient permissions to grant the given permissions

NullPointerException - if any element of the principals or permissions arrays is null

getGrants

public Permission[] getGrants(Class cl,
                              Principal[] principals)

If both underlying policy providers support dynamic grants, delegates to the getGrants method of the underlying policy associated with the loader of the given class (the loader-specific policy if the class loader is null, the same as or a child of the loader specified in the constructor for this instance, or the default loader otherwise). If at least one of the underlying policy providers does not support dynamic grants, throws an UnsupportedOperationException.

Specified by:

getGrants in interface DynamicPolicy

Parameters:

cl - class to query the permissions dynamically granted to the class loader of, or null if querying permissions granted across all class loaders

principals - if non-null, principals to query dynamic grants for

Returns:

new array containing the permissions dynamically granted to the indicated class loader (if any) and principals

Throws:

UnsupportedOperationException - if policy does not support dynamic grants, or if cl is non-null and belongs to a protection domain with a null class loader other than the system domain

NullPointerException - if any element of the principals array is null