Coverage Report - org.mule.module.json.JsonExpressionEvaluator
 
Classes in this File Line Coverage Branch Coverage Complexity
JsonExpressionEvaluator
0%
0/40
0%
0/42
7.333
 
 1  
 /*
 2  
  * $Id: JsonExpressionEvaluator.java 19191 2010-08-25 21:05:23Z tcarlson $
 3  
  * --------------------------------------------------------------------------------------
 4  
  * Copyright (c) MuleSoft, Inc.  All rights reserved.  http://www.mulesoft.com
 5  
  *
 6  
  * The software in this package is published under the terms of the CPAL v1.0
 7  
  * license, a copy of which has been included with this distribution in the
 8  
  * LICENSE.txt file.
 9  
  */
 10  
 package org.mule.module.json;
 11  
 
 12  
 import org.mule.api.MuleMessage;
 13  
 import org.mule.api.MuleRuntimeException;
 14  
 import org.mule.api.expression.ExpressionEvaluator;
 15  
 import org.mule.config.i18n.CoreMessages;
 16  
 import org.mule.util.NumberUtils;
 17  
 
 18  
 import org.apache.commons.logging.Log;
 19  
 import org.apache.commons.logging.LogFactory;
 20  
 
 21  
 /**
 22  
  * An expression evaluator to allow users to define json expressions in their mule configuration, i.e.
 23  
  * <code>
 24  
  * #[json:person/addresses[0]/postcode]
 25  
  * </code>
 26  
  * <p/>
 27  
  * See the {@link org.mule.module.json.JsonData} object for mor information about the query syntax.
 28  
  * <p/>
 29  
  * It is also possible to use this evaluator in {@link org.mule.routing.filters.ExpressionFilter} objects. For example
 30  
  * a filter could be defined as -
 31  
  * <p/>
 32  
  * <code>
 33  
  * #[json:person/registered]
 34  
  * </code>
 35  
  * <p/>
 36  
  * Where 'registered' is a boolean value.  It is also possible to filter on the existence of a value i.e.
 37  
  * <p/>
 38  
  * <code>
 39  
  * #[json:person/favouriteColour]
 40  
  * </code>
 41  
  * <p/>
 42  
  * Which would return true if 'favouriteColour' has been set. This evaluator also dds two logic operators you can use
 43  
  * to create more sophisticated boolean expressions; equals and not equals -
 44  
  * <p/>
 45  
  * <code>
 46  
  * #[json:person/favouriteColour = red]
 47  
  * </code>
 48  
  * <p/>
 49  
  * or
 50  
  * <p/>
 51  
  * <code>
 52  
  * #[json:person/favouriteColour != brown]
 53  
  * </code>
 54  
  *
 55  
  * @see org.mule.module.json.JsonData
 56  
  */
 57  0
 public class JsonExpressionEvaluator implements ExpressionEvaluator
 58  
 {
 59  
     /**
 60  
      * logger used by this class
 61  
      */
 62  0
     protected transient final Log logger = LogFactory.getLog(JsonExpressionEvaluator.class);
 63  
 
 64  
     public Object evaluate(String expression, MuleMessage message)
 65  
     {
 66  0
         String compareTo = null;
 67  0
         boolean not = false;
 68  0
         int start = expression.lastIndexOf("/");
 69  0
         if (start == -1)
 70  
         {
 71  0
             start = 0;
 72  
         }
 73  0
         int i=0;
 74  0
         if ((i = expression.indexOf("!=", start)) > -1)
 75  
         {
 76  0
             compareTo = expression.substring(i + 2, expression.length()).trim();
 77  0
             expression = expression.substring(0, i).trim();
 78  0
             not = true;
 79  
         }
 80  0
         else if ((i = expression.indexOf("=", start)) > -1)
 81  
         {
 82  0
             compareTo = expression.substring(i + 1, expression.length()).trim();
 83  0
             expression = expression.substring(0, i).trim();
 84  
         }
 85  
         
 86  
         try
 87  
         {
 88  0
             String json = message.getPayloadAsString();
 89  0
             JsonData data = new JsonData(json);
 90  
             try
 91  
             {
 92  0
                 Object result = data.get(expression);
 93  0
                 if (compareTo != null)
 94  
                 {
 95  0
                     if (compareTo.equalsIgnoreCase("null"))
 96  
                     {
 97  0
                         boolean answer = result == null;
 98  0
                         return (not ? !answer : answer);
 99  
                     }
 100  0
                     else if (result instanceof Number && NumberUtils.isDigits(compareTo))
 101  
                     {
 102  0
                         boolean answer = NumberUtils.createNumber(compareTo).equals(result);
 103  0
                         return (not ? !answer : answer);
 104  
                     }
 105  0
                     else if (result instanceof Boolean && (compareTo.equalsIgnoreCase("true") || compareTo.equalsIgnoreCase("false")))
 106  
                     {
 107  0
                         boolean answer = result.equals(Boolean.valueOf(compareTo));
 108  0
                         return (not ? !answer : answer);
 109  
                     }
 110  
                     else
 111  
                     {
 112  0
                         boolean answer = compareTo.equals(result);
 113  0
                         return (not ? !answer : answer);
 114  
                     }
 115  
                 }
 116  
                 else
 117  
                 {
 118  0
                     return result;
 119  
                 }
 120  
             }
 121  0
             catch (IllegalArgumentException e)
 122  
             {
 123  0
                 if (compareTo == null)
 124  
                 {
 125  0
                     logger.debug("returning null for json expression: " + expression + ": " + e.getMessage());
 126  0
                     return null;
 127  
                 }
 128  
                 //If the element does not exist but is matching against 'null' return true, otherwise false
 129  0
                 return (compareTo.equalsIgnoreCase("null")) & !not;
 130  
             }
 131  
         }
 132  0
         catch (Exception e)
 133  
         {
 134  0
             throw new MuleRuntimeException(CoreMessages.failedToProcessExtractorFunction(getName() + ":" + expression), e);
 135  
         }
 136  
     }
 137  
 
 138  
     public void setName(String name)
 139  
     {
 140  0
         throw new UnsupportedOperationException("setName");
 141  
     }
 142  
 
 143  
     public String getName()
 144  
     {
 145  0
         return "json";
 146  
     }
 147  
 }