Coverage Report - org.mule.api.expression.ExpressionManager
 
Classes in this File Line Coverage Branch Coverage Complexity
ExpressionManager
N/A
N/A
1
 
 1  
 /*
 2  
  * $Id: ExpressionManager.java 20424 2010-12-01 16:14:42Z dfeist $
 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.api.expression;
 11  
 
 12  
 import org.mule.api.MuleMessage;
 13  
 
 14  
 /**
 15  
  * Provides universal access for evaluating expressions embedded in Mule configurations, such  as Xml, Java,
 16  
  * scripting and annotations.
 17  
  * <p/>
 18  
  * Users can register or unregister {@link ExpressionEvaluator} through this interface.
 19  
  */
 20  
 public interface ExpressionManager
 21  
 {
 22  
     String DEFAULT_EXPRESSION_PREFIX = "#[";
 23  
     String DEFAULT_EXPRESSION_POSTFIX = "]";
 24  
 
 25  
     public void registerEvaluator(ExpressionEvaluator evaluator);
 26  
 
 27  
     /**
 28  
      * Checks whether an evaluator is registered with the manager
 29  
      *
 30  
      * @param name the name of the expression evaluator
 31  
      * @return true if the evaluator is registered with the manager, false otherwise
 32  
      */
 33  
     public boolean isEvaluatorRegistered(String name);
 34  
 
 35  
     /**
 36  
      * Removes the evaluator with the given name
 37  
      *
 38  
      * @param name the name of the evaluator to remove
 39  
      * @return the evaluator that was removed. This will be null if the evaluator was not registered
 40  
      */
 41  
     public ExpressionEvaluator unregisterEvaluator(String name);
 42  
     
 43  
     public void registerEnricher(ExpressionEnricher enricher);
 44  
 
 45  
     /**
 46  
      * Checks whether an enricher is registered with the manager
 47  
      *
 48  
      * @param name the name of the expression enricher
 49  
      * @return true if the enricher is registered with the manager, false otherwise
 50  
      */
 51  
     public boolean isEnricherRegistered(String name);
 52  
 
 53  
     /**
 54  
      * Removes the enricher with the given name
 55  
      *
 56  
      * @param name the name of the enricher to remove
 57  
      * @return the enricher that was removed. This will be null if the enricher was not registered
 58  
      */
 59  
     public ExpressionEnricher unregisterEnricher(String name);
 60  
 
 61  
     /**
 62  
      * Evaluates the given expression.  The expression should be a single expression definition with or without
 63  
      * enclosing braces. i.e. "mule:serviceName" and "#[mule:serviceName]" are both valid. For situations where
 64  
      * one or more expressions need to be parsed within a single text, the {@link #parse(String,org.mule.api.MuleMessage,boolean)}
 65  
      * method should be used since it will iterate through all expressions in a string.
 66  
      *
 67  
      * @param expression a single expression i.e. xpath://foo
 68  
      * @param message The current message being processed
 69  
      * @return the result of the evaluation
 70  
      * @throws ExpressionRuntimeException if the expression is invalid, or a null is found for the expression and
 71  
      *                                    'failIfNull is set to true.
 72  
      */
 73  
     public Object evaluate(String expression, MuleMessage message) throws ExpressionRuntimeException;
 74  
 
 75  
     /**
 76  
      * Evaluates the given expression.  The expression should be a single expression definition with or without
 77  
      * enclosing braces. i.e. "mule:serviceName" and "#[mule:serviceName]" are both valid. For situations where
 78  
      * one or more expressions need to be parsed within a single text, the {@link #parse(String,org.mule.api.MuleMessage,boolean)}
 79  
      * method should be used since it will iterate through all expressions in a string.
 80  
      *
 81  
      * @param expression a single expression i.e. xpath://foo
 82  
      * @param message The current message being processed
 83  
      * @param failIfNull determines if an exception should be thrown if expression could not be evaluated or returns
 84  
      *                   null. @return the result of the evaluation
 85  
      * @return the parsered expression string
 86  
      * @throws ExpressionRuntimeException if the expression is invalid, or a null is found for the expression and
 87  
      *                                    'failIfNull is set to true.
 88  
      */
 89  
     public Object evaluate(String expression, MuleMessage message, boolean failIfNull) throws ExpressionRuntimeException;
 90  
 
 91  
     /**
 92  
      * Evaluates the given expression.  The expression should be a single expression definition with or without
 93  
      * enclosing braces. i.e. "mule:serviceName" and "#[mule:serviceName]" are both valid. For situations where
 94  
      * one or more expressions need to be parsed within a single text, the {@link #parse(String,org.mule.api.MuleMessage,boolean)}
 95  
      * method should be used since it will iterate through all expressions in a string.
 96  
      *
 97  
      * @param expression one or more expressions ebedded in a literal string i.e. "Value is #[xpath://foo] other value is #[header:foo]."
 98  
      * @param evaluator  the evaluator to use when executing the expression
 99  
      * @param message The current message being processed
 100  
      * @param failIfNull determines if an exception should be thrown if expression could not be evaluated or returns
 101  
      *                   null. @return the result of the evaluation
 102  
      * @return the parsered expression string
 103  
      * @throws ExpressionRuntimeException if the expression is invalid, or a null is found for the expression and
 104  
      *                                    'failIfNull is set to true.
 105  
      */
 106  
     public Object evaluate(String expression, String evaluator, MuleMessage message, boolean failIfNull) throws ExpressionRuntimeException;
 107  
 
 108  
     /**
 109  
      * Evaluates the given expression resolving the result of the evaluation to a boolean.  The expression should be a single expression definition with or without
 110  
      * enclosing braces. i.e. "mule:serviceName" and "#[mule:serviceName]" are both valid. 
 111  
      * 
 112  
      * @param expression a single expression i.e. header:foo=bar
 113  
      * @param evaluator the evaluator to use when executing the expression
 114  
      * @param message The current message being processed
 115  
      * @return
 116  
      * @throws ExpressionRuntimeException
 117  
      */
 118  
     public boolean evaluateBoolean(String expression, String evaluator, MuleMessage message) throws ExpressionRuntimeException;
 119  
 
 120  
     /**
 121  
      * Evaluates the given expression resolving the result of the evaluation to a boolean.  The expression should be a single expression definition with or without
 122  
      * enclosing braces. i.e. "mule:serviceName" and "#[mule:serviceName]" are both valid.
 123  
      *
 124  
      * @param expression a single expression i.e. header:foo=bar
 125  
      * @param message The current message being processed
 126  
      * @return
 127  
      * @throws ExpressionRuntimeException
 128  
      */
 129  
     public boolean evaluateBoolean(String expression, MuleMessage message) throws ExpressionRuntimeException;
 130  
 
 131  
     /**
 132  
      * Evaluates the given expression resolving the result of the evaluation to a boolean.  The expression should be a single expression definition with or without
 133  
      * enclosing braces. i.e. "mule:serviceName" and "#[mule:serviceName]" are both valid. 
 134  
      *
 135  
      * @param expression a single expression i.e. header:foo=bar
 136  
      * @param evaluator the evaluator to use when executing the expression
 137  
      * @param message The current message being processed
 138  
      * @param nullReturnsTrue determines if true should be returned if the result of the evaluation is null
 139  
      * @param nonBooleanReturnsTrue determines if true should returned if the result is not null but isn't recognised as a boolean 
 140  
      * @return
 141  
      * @throws ExpressionRuntimeException
 142  
      */
 143  
     public boolean evaluateBoolean(String expression, String evaluator, MuleMessage message, boolean nullReturnsTrue, boolean nonBooleanReturnsTrue) throws ExpressionRuntimeException;
 144  
 
 145  
     /**
 146  
      * Evaluates the given expression resolving the result of the evaluation to a boolean.  The expression should be a single expression definition with or without
 147  
      * enclosing braces. i.e. "mule:serviceName" and "#[mule:serviceName]" are both valid. 
 148  
      *
 149  
      * @param expression a single expression i.e. header:foo=bar
 150  
      * @param message The current message being processed
 151  
      * @param nullReturnsTrue determines if true should be returned if the result of the evaluation is null
 152  
      * @param nonBooleanReturnsTrue determines if true should returned if the result is not null but isn't recognised as a boolean 
 153  
      * @return
 154  
      * @throws ExpressionRuntimeException
 155  
      */
 156  
     public boolean evaluateBoolean(String expression, MuleMessage message, boolean nullReturnsTrue, boolean nonBooleanReturnsTrue) throws ExpressionRuntimeException;
 157  
 
 158  
     /**
 159  
      * Enriches the current message using 
 160  
      * @param expression a single expression i.e. header://foo that defines how the message shoud be enriched
 161  
      * @param message The current message being processed that will be enriched
 162  
      * @param object The object that will be used to enrich the message
 163  
      */
 164  
     public void enrich(String expression, MuleMessage message, Object object);
 165  
 
 166  
     /**
 167  
      * Enriches the current message
 168  
      * @param expression a single expression i.e. header://foo that defines how the message shoud be enriched
 169  
      * @param enricher the enricher to use when executing the expression
 170  
      * @param message The current message being processed that will be enriched
 171  
      * @param object The object that will be used to enrich the message
 172  
      */
 173  
     public void enrich(String expression, String enricher, MuleMessage message, Object object);
 174  
     
 175  
     /**
 176  
      * Evaluates expressions in a given string. This method will iterate through each expression and evaluate it. If
 177  
      * a user needs to evaluate a single expression they can use {@link #evaluate(String,org.mule.api.MuleMessage,boolean)}.
 178  
      *
 179  
      * @param expression one or more expressions ebedded in a literal string i.e. "Value is #[xpath://foo] other value is #[header:foo]."
 180  
      * @param message The current message being processed
 181  
      * @return the result of the evaluation
 182  
      * @throws org.mule.api.expression.ExpressionRuntimeException
 183  
      *          if the expression is invalid, or a null is found for the expression and
 184  
      *          'failIfNull is set to true.
 185  
      */
 186  
     public String parse(String expression, MuleMessage message) throws ExpressionRuntimeException;
 187  
 
 188  
     /**
 189  
      * Evaluates expressions in a given string. This method will iterate through each expression and evaluate it. If
 190  
      * a user needs to evaluate a single expression they can use {@link #evaluate(String,org.mule.api.MuleMessage,boolean)}.
 191  
      *
 192  
      * @param expression one or more expressions ebedded in a literal string i.e. "Value is #[xpath://foo] other value is #[header:foo]."
 193  
      * @param message The current message being processed
 194  
      * @param failIfNull determines if an exception should be thrown if expression could not be evaluated or returns
 195  
      *                   null. @return the result of the evaluation
 196  
      * @return the parsered expression string
 197  
      * @throws ExpressionRuntimeException if the expression is invalid, or a null is found for the expression and
 198  
      *                                    'failIfNull is set to true.
 199  
      */
 200  
     public String parse(final String expression, final MuleMessage message, final boolean failIfNull) throws ExpressionRuntimeException;
 201  
 
 202  
     /**
 203  
      * Clears all registered evaluators from the manager.
 204  
      */
 205  
     public void clearEvaluators();
 206  
     
 207  
     /**
 208  
      * Clears all registered enrichers from the manager.
 209  
      */
 210  
     public void clearEnrichers();
 211  
 
 212  
     /**
 213  
      * Determines if the expression is valid or not.  This method will validate a single expression or
 214  
      * expressions embedded in a string.  the expression must be well formed i.e. #[bean:user]
 215  
      *
 216  
      * @param expression the expression to validate
 217  
      * @return true if the expression evaluator is recognised
 218  
      */
 219  
     public boolean isValidExpression(String expression);
 220  
 
 221  
     /**
 222  
      * Determines if the expression is valid or not.  This method will validate a single expression or
 223  
      * expressions embedded in a string.  the expression must be well formed i.e. #[bean:user]
 224  
      *
 225  
      * @param expression the expression to validate
 226  
      * @throws InvalidExpressionException if the expression is invalid, including information about the position and fault
 227  
      *
 228  
      * @since 3.0
 229  
      */
 230  
     public void validateExpression(String expression) throws InvalidExpressionException;
 231  
 
 232  
     /**
 233  
      * Determines if the string is an expression.  This method will validate that the string contains either the expression
 234  
      * prefix (malformed) or a full expression.  This isn't full proof but catches most error cases
 235  
      *
 236  
      * @param string is this string an expression string
 237  
      * @return true if the string contains an expression
 238  
      *
 239  
      * @since 3.0
 240  
      */
 241  
     public boolean isExpression(String string);
 242  
 
 243  
 }