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      1 /*
      2  * Licensed to the Apache Software Foundation (ASF) under one
      3  * or more contributor license agreements. See the NOTICE file
      4  * distributed with this work for additional information
      5  * regarding copyright ownership. The ASF licenses this file
      6  * to you under the Apache License, Version 2.0 (the  "License");
      7  * you may not use this file except in compliance with the License.
      8  * You may obtain a copy of the License at
      9  *
     10  *     http://www.apache.org/licenses/LICENSE-2.0
     11  *
     12  * Unless required by applicable law or agreed to in writing, software
     13  * distributed under the License is distributed on an "AS IS" BASIS,
     14  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
     15  * See the License for the specific language governing permissions and
     16  * limitations under the License.
     17  */
     18 /*
     19  * $Id: FuncSystemProperty.java 468655 2006-10-28 07:12:06Z minchau $
     20  */
     21 package org.apache.xpath.functions;
     22 
     23 import java.io.BufferedInputStream;
     24 import java.io.InputStream;
     25 import java.util.Properties;
     26 
     27 import org.apache.xpath.XPathContext;
     28 import org.apache.xpath.objects.XNumber;
     29 import org.apache.xpath.objects.XObject;
     30 import org.apache.xpath.objects.XString;
     31 import org.apache.xpath.res.XPATHErrorResources;
     32 
     33 /**
     34  * Execute the SystemProperty() function.
     35  * @xsl.usage advanced
     36  */
     37 public class FuncSystemProperty extends FunctionOneArg
     38 {
     39     static final long serialVersionUID = 3694874980992204867L;
     40   /**
     41    * The path/filename of the property file: XSLTInfo.properties
     42    * Maintenance note: see also
     43    * org.apache.xalan.processor.TransformerFactoryImpl.XSLT_PROPERTIES
     44    */
     45   static final String XSLT_PROPERTIES =
     46             "org/apache/xalan/res/XSLTInfo.properties";
     47 
     48   /**
     49    * Execute the function.  The function must return
     50    * a valid object.
     51    * @param xctxt The current execution context.
     52    * @return A valid XObject.
     53    *
     54    * @throws javax.xml.transform.TransformerException
     55    */
     56   public XObject execute(XPathContext xctxt) throws javax.xml.transform.TransformerException
     57   {
     58 
     59     String fullName = m_arg0.execute(xctxt).str();
     60     int indexOfNSSep = fullName.indexOf(':');
     61     String result = null;
     62     String propName = "";
     63 
     64     // List of properties where the name of the
     65     // property argument is to be looked for.
     66     Properties xsltInfo = new Properties();
     67 
     68     loadPropertyFile(XSLT_PROPERTIES, xsltInfo);
     69 
     70     if (indexOfNSSep > 0)
     71     {
     72       String prefix = (indexOfNSSep >= 0)
     73                       ? fullName.substring(0, indexOfNSSep) : "";
     74       String namespace;
     75 
     76       namespace = xctxt.getNamespaceContext().getNamespaceForPrefix(prefix);
     77       propName = (indexOfNSSep < 0)
     78                  ? fullName : fullName.substring(indexOfNSSep + 1);
     79 
     80       if (namespace.startsWith("http://www.w3.org/XSL/Transform")
     81               || namespace.equals("http://www.w3.org/1999/XSL/Transform"))
     82       {
     83         result = xsltInfo.getProperty(propName);
     84 
     85         if (null == result)
     86         {
     87           warn(xctxt, XPATHErrorResources.WG_PROPERTY_NOT_SUPPORTED,
     88                new Object[]{ fullName });  //"XSL Property not supported: "+fullName);
     89 
     90           return XString.EMPTYSTRING;
     91         }
     92       }
     93       else
     94       {
     95         warn(xctxt, XPATHErrorResources.WG_DONT_DO_ANYTHING_WITH_NS,
     96              new Object[]{ namespace,
     97                            fullName });  //"Don't currently do anything with namespace "+namespace+" in property: "+fullName);
     98 
     99         try
    100         {
    101             //if secure procession is enabled only handle required properties do not not map any valid system property
    102             if(!xctxt.isSecureProcessing())
    103             {
    104                 result = System.getProperty(propName);
    105             }
    106             else
    107             {
    108                 warn(xctxt, XPATHErrorResources.WG_SECURITY_EXCEPTION,
    109                         new Object[]{ fullName });  //"SecurityException when trying to access XSL system property: "+fullName);
    110             }
    111             if (null == result)
    112             {
    113                 return XString.EMPTYSTRING;
    114             }
    115         }
    116         catch (SecurityException se)
    117         {
    118           warn(xctxt, XPATHErrorResources.WG_SECURITY_EXCEPTION,
    119                new Object[]{ fullName });  //"SecurityException when trying to access XSL system property: "+fullName);
    120 
    121           return XString.EMPTYSTRING;
    122         }
    123       }
    124     }
    125     else
    126     {
    127       try
    128       {
    129           //if secure procession is enabled only handle required properties do not not map any valid system property
    130           if(!xctxt.isSecureProcessing())
    131           {
    132               result = System.getProperty(fullName);
    133           }
    134           else
    135           {
    136               warn(xctxt, XPATHErrorResources.WG_SECURITY_EXCEPTION,
    137                       new Object[]{ fullName });  //"SecurityException when trying to access XSL system property: "+fullName);
    138           }
    139           if (null == result)
    140           {
    141               return XString.EMPTYSTRING;
    142           }
    143       }
    144       catch (SecurityException se)
    145       {
    146         warn(xctxt, XPATHErrorResources.WG_SECURITY_EXCEPTION,
    147              new Object[]{ fullName });  //"SecurityException when trying to access XSL system property: "+fullName);
    148 
    149         return XString.EMPTYSTRING;
    150       }
    151     }
    152 
    153     if (propName.equals("version") && result.length() > 0)
    154     {
    155       try
    156       {
    157         // Needs to return the version number of the spec we conform to.
    158         return new XString("1.0");
    159       }
    160       catch (Exception ex)
    161       {
    162         return new XString(result);
    163       }
    164     }
    165     else
    166       return new XString(result);
    167   }
    168 
    169   /**
    170    * Retrieve a propery bundle from a specified file
    171    *
    172    * @param file The string name of the property file.  The name
    173    * should already be fully qualified as path/filename
    174    * @param target The target property bag the file will be placed into.
    175    */
    176   public void loadPropertyFile(String file, Properties target)
    177   {
    178     try
    179     {
    180       // Use SecuritySupport class to provide priveleged access to property file
    181       SecuritySupport ss = SecuritySupport.getInstance();
    182 
    183       InputStream is = ss.getResourceAsStream(ObjectFactory.findClassLoader(),
    184                                               file);
    185 
    186       // get a buffered version
    187       BufferedInputStream bis = new BufferedInputStream(is);
    188 
    189       target.load(bis);  // and load up the property bag from this
    190       bis.close();  // close out after reading
    191     }
    192     catch (Exception ex)
    193     {
    194       // ex.printStackTrace();
    195       throw new org.apache.xml.utils.WrappedRuntimeException(ex);
    196     }
    197   }
    198 }
    199