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 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.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  
     /**
 44  
      * Evaluates the given expression.  The expression should be a single expression definition with or without
 45  
      * enclosing braces. i.e. "mule:serviceName" and "#[mule:serviceName]" are both valid. For situations where
 46  
      * one or more expressions need to be parsed within a single text, the {@link #parse(String,org.mule.api.MuleMessage,boolean)}
 47  
      * method should be used since it will iterate through all expressions in a string.
 48  
      *
 49  
      * @param expression a single expression i.e. xpath://foo
 50  
      * @param message The current message being processed
 51  
      * @return the result of the evaluation
 52  
      * @throws ExpressionRuntimeException if the expression is invalid, or a null is found for the expression and
 53  
      *                                    'failIfNull is set to true.
 54  
      */
 55  
     public Object evaluate(String expression, MuleMessage message) throws ExpressionRuntimeException;
 56  
 
 57  
     /**
 58  
      * Evaluates the given expression.  The expression should be a single expression definition with or without
 59  
      * enclosing braces. i.e. "mule:serviceName" and "#[mule:serviceName]" are both valid. For situations where
 60  
      * one or more expressions need to be parsed within a single text, the {@link #parse(String,org.mule.api.MuleMessage,boolean)}
 61  
      * method should be used since it will iterate through all expressions in a string.
 62  
      *
 63  
      * @param expression a single expression i.e. xpath://foo
 64  
      * @param message The current message being processed
 65  
      * @param failIfNull determines if an exception should be thrown if expression could not be evaluated or returns
 66  
      *                   null. @return the result of the evaluation
 67  
      * @return the parsered expression string
 68  
      * @throws ExpressionRuntimeException if the expression is invalid, or a null is found for the expression and
 69  
      *                                    'failIfNull is set to true.
 70  
      */
 71  
     public Object evaluate(String expression, MuleMessage message, boolean failIfNull) throws ExpressionRuntimeException;
 72  
 
 73  
     /**
 74  
      * Evaluates the given expression.  The expression should be a single expression definition with or without
 75  
      * enclosing braces. i.e. "mule:serviceName" and "#[mule:serviceName]" are both valid. For situations where
 76  
      * one or more expressions need to be parsed within a single text, the {@link #parse(String,org.mule.api.MuleMessage,boolean)}
 77  
      * method should be used since it will iterate through all expressions in a string.
 78  
      *
 79  
      * @param expression one or more expressions ebedded in a literal string i.e. "Value is #[xpath://foo] other value is #[header:foo]."
 80  
      * @param evaluator  the evaluator to use when executing the expression
 81  
      * @param message The current message bing processed
 82  
      * @param failIfNull determines if an exception should be thrown if expression could not be evaluated or returns
 83  
      *                   null. @return the result of the evaluation
 84  
      * @return the parsered expression string
 85  
      * @throws ExpressionRuntimeException if the expression is invalid, or a null is found for the expression and
 86  
      *                                    'failIfNull is set to true.
 87  
      */
 88  
     public Object evaluate(String expression, String evaluator, MuleMessage message, boolean failIfNull) throws ExpressionRuntimeException;
 89  
 
 90  
 
 91  
     /**
 92  
      * Evaluates expressions in a given string. This method will iterate through each expression and evaluate it. If
 93  
      * a user needs to evaluate a single expression they can use {@link #evaluate(String,org.mule.api.MuleMessage,boolean)}.
 94  
      *
 95  
      * @param expression one or more expressions ebedded in a literal string i.e. "Value is #[xpath://foo] other value is #[header:foo]."
 96  
      * @param message The current message being processed
 97  
      * @return the result of the evaluation
 98  
      * @throws org.mule.api.expression.ExpressionRuntimeException
 99  
      *          if the expression is invalid, or a null is found for the expression and
 100  
      *          'failIfNull is set to true.
 101  
      */
 102  
     public String parse(String expression, MuleMessage message) throws ExpressionRuntimeException;
 103  
 
 104  
     /**
 105  
      * Evaluates expressions in a given string. This method will iterate through each expression and evaluate it. If
 106  
      * a user needs to evaluate a single expression they can use {@link #evaluate(String,org.mule.api.MuleMessage,boolean)}.
 107  
      *
 108  
      * @param expression one or more expressions ebedded in a literal string i.e. "Value is #[xpath://foo] other value is #[header:foo]."
 109  
      * @param message The current message being processed
 110  
      * @param failIfNull determines if an exception should be thrown if expression could not be evaluated or returns
 111  
      *                   null. @return the result of the evaluation
 112  
      * @return the parsered expression string
 113  
      * @throws ExpressionRuntimeException if the expression is invalid, or a null is found for the expression and
 114  
      *                                    'failIfNull is set to true.
 115  
      */
 116  
     public String parse(final String expression, final MuleMessage message, final boolean failIfNull) throws ExpressionRuntimeException;
 117  
 
 118  
     /**
 119  
      * Clears all registered evaluators from the manager.
 120  
      */
 121  
     public void clearEvaluators();
 122  
 
 123  
     /**
 124  
      * Determines if the expression is valid or not.  This method will validate a single expression or
 125  
      * expressions embedded in a string.  the expression must be well formed i.e. #[bean:user]
 126  
      *
 127  
      * @param expression the expression to validate
 128  
      * @return true if the expression evaluator is recognised
 129  
      */
 130  
     public boolean isValidExpression(String expression);
 131  
 
 132  
     /**
 133  
      * Determines if the expression is valid or not.  This method will validate a single expression or
 134  
      * expressions embedded in a string.  the expression must be well formed i.e. #[bean:user]
 135  
      *
 136  
      * @param expression the expression to validate
 137  
      * @throws InvalidExpressionException if the expression is invalid, including information about the position and fault
 138  
      *
 139  
      * @since 3.0
 140  
      */
 141  
     public void validateExpression(String expression) throws InvalidExpressionException;
 142  
 
 143  
     /**
 144  
      * Determines if the string is an expression.  This method will validate that the string contains either the expression
 145  
      * prefix (malformed) or a full expression.  This isn't full proof but catches most error cases
 146  
      *
 147  
      * @param string is this string an expression string
 148  
      * @return true if the string contains an expression
 149  
      *
 150  
      * @since 3.0
 151  
      */
 152  
     public boolean isExpression(String string);
 153  
 
 154  
 }