| EnvironmentNode | Line # 59 | 20 | 8 | 57.6% |
0.57575756
|
| No Tests | |||
| 1 | /* | |
| 2 | * Copyright (c) 2000-2005, University of Salford | |
| 3 | * All rights reserved. | |
| 4 | * | |
| 5 | * Redistribution and use in source and binary forms, with or without | |
| 6 | * modification, are permitted provided that the following conditions are met: | |
| 7 | * | |
| 8 | * Redistributions of source code must retain the above copyright notice, this | |
| 9 | * list of conditions and the following disclaimer. | |
| 10 | * | |
| 11 | * Redistributions in binary form must reproduce the above copyright notice, | |
| 12 | * this list of conditions and the following disclaimer in the documentation | |
| 13 | * and/or other materials provided with the distribution. | |
| 14 | * | |
| 15 | * Neither the name of the University of Salford nor the names of its | |
| 16 | * contributors may be used to endorse or promote products derived from this | |
| 17 | * software without specific prior written permission. | |
| 18 | * | |
| 19 | * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" | |
| 20 | * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE | |
| 21 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE | |
| 22 | * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE | |
| 23 | * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR | |
| 24 | * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF | |
| 25 | * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS | |
| 26 | * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN | |
| 27 | * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) | |
| 28 | * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE | |
| 29 | * POSSIBILITY OF SUCH DAMAGE. | |
| 30 | */ | |
| 31 | ||
| 32 | package issrg.pba.rbac.xmlpolicy.ifstatement; | |
| 33 | ||
| 34 | /** | |
| 35 | * This is the class that represents an Environment node and evaluates the | |
| 36 | * environmental variables | |
| 37 | * at run-time. | |
| 38 | * | |
| 39 | * <p>EnvironmentNode expects the environment to contain either | |
| 40 | * issrg.pba.rbac.Argument objects, in which case the string value will be | |
| 41 | * converted using Types.construct, or other objects, which will be passed | |
| 42 | * as is to the interpreters. | |
| 43 | * | |
| 44 | * <p>If the environment contains the variables of types for which there is no | |
| 45 | * constructor provided | |
| 46 | * by the AEF (not registered with the Types), or the AEF failed to provide the | |
| 47 | * variable with the name | |
| 48 | * stated in the policy, an EvaluationException will occur at run-time. | |
| 49 | * | |
| 50 | * <p>Note that if the evaluation does not reach the point where the variable | |
| 51 | * is needed, no | |
| 52 | * exception will be thrown. | |
| 53 | * | |
| 54 | * @see Types#construct | |
| 55 | * | |
| 56 | * @author A.Otenko | |
| 57 | */ | |
| 58 | ||
| 59 | public class EnvironmentNode extends TermNode { | |
| 60 | /** | |
| 61 | * This is the name of the node that represents the Environment - a reference to an environmental | |
| 62 | * parameter. | |
| 63 | */ | |
| 64 | public final static String ENVIRONMENT_NODE = "Environment"; | |
| 65 | ||
| 66 | /** | |
| 67 | * This is the name of the attribute telling the name of the environmental parameter. | |
| 68 | */ | |
| 69 | public final static String PARAMETER_ATTRIBUTE = "Parameter"; | |
| 70 | ||
| 71 | /** | |
| 72 | * This method should be called to register the node with the XML Parser | |
| 73 | */ | |
| 74 | 21 |
 public static void register(){ |
| 75 | 21 | try{ |
| 76 | 21 | issrg.pba.rbac.xmlpolicy.XMLPolicyParser.registerXMLNode(ENVIRONMENT_NODE, EnvironmentNode.class); |
| 77 | }catch (NoSuchMethodException nsme){ | |
| 78 | 0 | nsme.printStackTrace(); |
| 79 | } | |
| 80 | } | |
| 81 | ||
| 82 | protected String type; | |
| 83 | protected String parameter_name; | |
| 84 | ||
| 85 | 0 |
protected EnvironmentNode() {} |
| 86 | ||
| 87 | /** | |
| 88 | * This constructor builds an EnvironmentNode given the XMLPolicyParser and | |
| 89 | * the set of attributes of the XML element. It expects that a | |
| 90 | * issrg.pba.rbac.xmlpolicy.XMLTags.TYPE_ATTRIBUTE and | |
| 91 | * PARAMETER_ATTRIBUTE ("Type" and "Parameter") are | |
| 92 | * present in this XML element. The value is converted from string into a | |
| 93 | * Java object using the Types.construct() method at runtime, so the type of | |
| 94 | * the value | |
| 95 | * must be registered there. | |
| 96 | * | |
| 97 | * @param p - the XMLPolicyParser that builds this EnvironmentNode | |
| 98 | * @param attr - the attributes of this XML element | |
| 99 | * @see Types#construct | |
| 100 | */ | |
| 101 | 22 |
public EnvironmentNode(issrg.pba.rbac.xmlpolicy.XMLPolicyParser p, org.xml.sax.Attributes attr) throws issrg.pba.rbac.PolicyParsingException{ |
| 102 | 22 | super(ENVIRONMENT_NODE, attr, -1, 0); |
| 103 | ||
| 104 | 22 | type=((String)getAttributes().get(issrg.pba.rbac.xmlpolicy.XMLTags.TYPE_ATTRIBUTE)).intern(); |
| 105 | 0 | if (type==null) throw new issrg.pba.rbac.PolicyParsingException(issrg.pba.rbac.xmlpolicy.XMLTags.TYPE_ATTRIBUTE+" attribute was expected in "+ENVIRONMENT_NODE); |
| 106 | 22 | parameter_name=(String)getAttributes().get(PARAMETER_ATTRIBUTE); |
| 107 | 0 | if (parameter_name==null) throw new issrg.pba.rbac.PolicyParsingException(PARAMETER_ATTRIBUTE+" attribute was expected in "+ENVIRONMENT_NODE); |
| 108 | } | |
| 109 | ||
| 110 | /** | |
| 111 | * This method returns the type of the environmental parameter as determined | |
| 112 | * at construction type. | |
| 113 | */ | |
| 114 | 330 |
public String getType(){ |
| 115 | 330 | return type; |
| 116 | } | |
| 117 | ||
| 118 | /** | |
| 119 | * This method evaluates the environmental parameter, as it is at run-time. | |
| 120 | * It looks for the environmental parameter in the Environment by its name, | |
| 121 | * as determined at construction time. If the value is of type other than | |
| 122 | * issrg.pba.rbac.Argument, then it is the result of this method; otherwise | |
| 123 | * the String value of the issrg.pba.rbac.Argument is extracted and decoded | |
| 124 | * into a Java object using Types.construct method. | |
| 125 | * | |
| 126 | * @param env - the Environment with the variables in it indexed by their | |
| 127 | * name | |
| 128 | * | |
| 129 | * @return Object of type guaranteed by getType() method | |
| 130 | * | |
| 131 | * @throws EvaluationException, if there is no variable in the Environment | |
| 132 | * with the expected name, or if its type is not the expected type, or if | |
| 133 | * Types.construct failed to decode the value from String (no decoder | |
| 134 | * registered or other decoding problem) | |
| 135 | * | |
| 136 | * @see Types#construct | |
| 137 | */ | |
| 138 | 122 |
public Object evaluate(Environment env) throws EvaluationException{ |
| 139 | 122 | try{ |
| 140 | 122 | Object o = env.getEnv().get(parameter_name); |
| 141 | 122 | if (o instanceof issrg.pba.rbac.Argument){ |
| 142 | 0 | issrg.pba.rbac.Argument arg = (issrg.pba.rbac.Argument)o; |
| 143 | ||
| 144 | 0 | if (arg==null || arg.getType().intern()!=type){ |
| 145 | 0 | throw new EvaluationException("No such variable in the environment: "+parameter_name+" of type "+type); |
| 146 | } | |
| 147 | ||
| 148 | 0 | return Types.construct(type, arg.getValue()); |
| 149 | }else{ | |
| 150 | 122 | return o; |
| 151 | } | |
| 152 | }catch (Throwable th){ | |
| 153 | 0 | throw new EvaluationException("Evaluation run-time error", th); |
| 154 | } | |
| 155 | } | |
| 156 | } | |
|
||||||||||
