permission.java

这是一个基于角色的访问控制程序

/*
 * ====================================================================
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 * The Apache Software License, Version 1.1
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 * Copyright (c) 1999 The Apache Software Foundation.  All rights
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 * Portions of this software are based upon public domain software 
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package gov.nist.security.rbac;

import java.util.*;
/** A default implementation of the IPermission interface. */
public class Permission extends AbstractPermission {
  /** The current set of permission entries. */
  private final IPermissionEntry[] entries;
  /**
   * Constructs with a set of permission entries.
   * Note that client is responsible for ensuring there is no duplicate entries
   * in the specified permission entry list.
   */
  public Permission(IPermissionEntry[] entries) {
    this.entries = entries;
  }
  /**
   * Constructs with a single permission entry.
   * @param obj the target object.
   * @param op the operation.
   */
  public Permission(Object obj, String op) {
    this.entries = new IPermissionEntry[]{new PermissionEntry(obj, op)};
  }
  /**
   * Constructs with a set of permission objects.
   */
  public Permission(IPermission[] p) {
    Set set = new HashSet();
    for (int i=0; i < p.length; i++) {
      IPermissionEntry[] e = p[i].getPermissionEntries();
      for (int j=0; j < e.length; j++) {
        set.add(e[j]);
      }
    }
    this.entries = (IPermissionEntry[])set.toArray(IPermissionEntry.ZERO_PERMISSION_ENTRY);
  }
  /** Returns the permission entry set of this permission. */
  public IPermissionEntry[] getPermissionEntries() {
    return entries;
  }
}