# PolicyReaderMBean (Abstract)

Overview | Related MBeans | Attributes | Operations

## Overview

Provides a set of methods for reading data about policies. An Authorization-provider MBean can optionally extend this MBean. The WebLogic Server Administration Console detects when an Authorization provider extends this MBean and automatically provides a GUI for using these methods.

Fully Qualified Interface Name | If you use the `getMBeanInfo` operation in MBeanTypeServiceMBean, supply the following value as this MBean's fully qualified interface name: `weblogic.management.security.authorization.PolicyReaderMBean`
Factory Methods | No factory methods. Instances of this MBean are created automatically.

## Operations

This section describes the following operations:

getPolicyExpression policyExists | wls_getDisplayName

### getPolicyExpression

Returns the expression of an existing policy.

Operation Name | `"getPolicyExpression"`
Parameters | `Object [] { resourceId }` where: `resourceId` is an object of type `java.lang.String` that specifies: - The resource for which this method returns the policy expression. A null value will trigger NullPointerException.
Signature | `String [] { "java.lang.String" }`
Returns | `String`
Exceptions | `weblogic.management.utils.NotFoundException`

### policyExists

Indicates whether a policy exists for a resource.

Operation Name | `"policyExists"`
Parameters | `Object [] { resourceId }` where: `resourceId` is an object of type `java.lang.String` that specifies: - The resource within which this method searches for a policy. A null value will trigger NullPointerException.
Signature | `String [] { "java.lang.String" }`
Returns | `boolean`

### wls_getDisplayName

Operation Name | `"wls_getDisplayName"`
Parameters | `null`
Signature | `null`
Returns | `String`