![Using OGNL Expressions
• OGNL is a simple yet very powerful expression
language for plain Java objects. Similar to JXPath,
it works on object graphs, and thus the
corresponding filter enables simple and efficient
content routing for payloads. For example:
• <expression-filter evaluator="ognl"
expression="[MULE:0].equals(42)"/>
• or more simply:
• <ognl-filter expression="[MULE:0].equals(42)"/>](https://image.slidesharecdn.com/filtersinmule-150706080643-lva1-app6892/85/Filters-in-mule-7-320.jpg)
Filters in mule
- 2. Standard Filters • Mule includes the following standard filters that you can apply to your routers: • Payload Type Filter Expression Filter • Using XPath Expressions • Using JXPath Expressions • Using OGNL Expressions • RegEx Filter • Wildcard Filter • Exception Type Filter • Message Property Filter Logic Filters • And Filter • Or Filter • Not Filter
- 3. Payload Type Filter • Checks the class type of the payload object inside a message. • Example: <payload-type-filter expectedType="java.lang.String"/>
- 4. Expression Filter • Evaluates a range of expressions. Use the evaluator attribute to specify the expression evaluator to use, one of the following: header, payload-type, exception- type, wildcard, regex, ognl, xpath, jxpath, bean, groovy, or custom. Use the expression attribute to set the actual expression. If the expression type is xpath, bean, or ognl, the expression should be a boolean
- 5. Using XPath Expressions • XPath expressions are supported using the standard XPath query language. It is based on JAXP, the Java API for XML processing. You can learn more about writing XPath queries from the XPath tutorial. Example: <expression-filter evaluator="xpath" expression="(msg/header/resultcode)='succes s'"/>
- 6. Using JXPath Expressions • JXPath is an XPath interpreter that can apply XPath expressions to graphs of objects of all kinds: JavaBeans, Maps, Servlet contexts, DOM etc, including mixtures thereof. For more information about JXPath, see the JXpath user guide. For querying XML, it is recommended to use XPath expressions instead. • <expression-filter evaluator="jxpath" expression="(msg/header/resultcode)='success'" />
- 7. Using OGNL Expressions • OGNL is a simple yet very powerful expression language for plain Java objects. Similar to JXPath, it works on object graphs, and thus the corresponding filter enables simple and efficient content routing for payloads. For example: • <expression-filter evaluator="ognl" expression="[MULE:0].equals(42)"/> • or more simply: • <ognl-filter expression="[MULE:0].equals(42)"/>