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<TITLE>Listing All Permissions Granted to a Loaded Class (Java Developers Almanac Example)
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<B><A HREF="../java.security/pkg.html#Permissions">Permissions</A></B><font color="#666666" class="xsmall-font">
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<h3>e217. Listing All Permissions Granted to a Loaded Class</h3>
This example retrieves all the permissions granted to a particular
class. These permissions are effective only if a security manager is
installed (see <a href="../java.security/CustSecurityMgr.html" class="eglink"><b>e212</b> Enabling the Security Manager</a>). However,
with a security manager installed, a class will require permission to
execute <code>Class.getProtectionDomain()</code> and <code>Policy.getPermissions()</code>.
<pre> // Get the protection domain for the class
ProtectionDomain domain = <font color="#0066ff"><i>this.getClass()</i></font>.getProtectionDomain();
// With the protection domain, get all the permissions from the Policy object
PermissionCollection pcoll = Policy.getPolicy().getPermissions(domain);
// View each permission in the permission collection
Enumeration enum = pcoll.elements();
for (; enum.hasMoreElements(); ) {
Permission p = (Permission)enum.nextElement();
}
</pre>
Here's the list of permissions for a class under the default policy file:
<pre> (java.lang.RuntimePermission exitVM)
(java.lang.RuntimePermission stopThread)
(java.util.PropertyPermission java.specification.vendor read)
(java.util.PropertyPermission java.vm.specification.vendor read)
(java.util.PropertyPermission path.separator read)
(java.util.PropertyPermission java.vm.name read)
(java.util.PropertyPermission java.class.version read)
(java.util.PropertyPermission os.name read)
(java.util.PropertyPermission java.vendor.url read)
(java.util.PropertyPermission java.vendor read)
(java.util.PropertyPermission java.vm.vendor read)
(java.util.PropertyPermission file.separator read)
(java.util.PropertyPermission os.version read)
(java.util.PropertyPermission java.vm.version read)
(java.util.PropertyPermission java.version read)
(java.util.PropertyPermission line.separator read)
(java.util.PropertyPermission java.vm.specification.version read)
(java.util.PropertyPermission java.specification.name read)
(java.util.PropertyPermission java.vm.specification.name read)
(java.util.PropertyPermission java.specification.version read)
(java.util.PropertyPermission os.arch read)
(java.net.SocketPermission localhost:1024- listen,resolve)
(java.io.FilePermission \C:\users\almanac\- read)
</pre>
Here's the list of permissions for the <code>java.lang.String</code> class which
is loaded with the system class loader:
<pre> (java.security.AllPermission <all permissions> <all actions>)
</pre>
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<b>Related Examples</b></font></td>
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e212. <a class="eglink" href="CustSecurityMgr.html?l=rel">
Enabling the Security Manager
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e213. <a class="eglink" href="CheckPermission.html?l=rel">
Checking Read/Write Permission for a Directory
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e214. <a class="eglink" href="CheckImplies.html?l=rel">
Determining If One Permission Implies Another
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e215. <a class="eglink" href="CustPerm.html?l=rel">
Creating a Custom Permission
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e216. <a class="eglink" href="GuardObj.html?l=rel">
Controlling Access to an Object
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e218. <a class="eglink" href="ListUrlPerm.html?l=rel">
Listing All Permissions Granted to Classes Loaded from a URL or Directory
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See also:
<a class="eglink" href="/egs/java.security/pkg.html?l=rel#Key%20Store">
Key Store
</a>
<a class="eglink" href="/egs/java.security/pkg.html?l=rel#Message%20Digests">
Message Digests
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<a class="eglink" href="/egs/java.security/pkg.html?l=rel#Policy%20Files">
Policy Files
</a>
<a class="eglink" href="/egs/java.security/pkg.html?l=rel#Public%20and%20Private%20Keys">
Public and Private Keys
</a>
<a class="eglink" href="/egs/java.security/pkg.html?l=rel#Signatures">
Signatures
</a>
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