Languages

-

To support flexible and powerful Enterprise Integration Patterns Camel supports various Languages to create an Expression or Predicate within either the Routing Domain Specific Language or the Xml Configuration. The following languages are supported

+

To support flexible and powerful Enterprise Integration Patterns Camel supports various Languages to create an Expression or Predicate within either the Routing Domain Specific Language or the Xml Configuration.

+ +

Combining Predicates
When creating predicates (expressions that evaluate to true or false), you can combine several predicates - regardless of the language they are built with - by using the PredicateBuilder class. For more information, see Compound Predicates.

+ +

The following languages are supported:

Bean Language for using Java for expressions
Constant
the unified EL from JSP and JSF
Header
JXPath
Mvel
OGNL
Ref Language
Property
Scripting Languages such as
Modified: websites/production/camel/content/predicate.html ============================================================================== --- websites/production/camel/content/predicate.html (original) +++ websites/production/camel/content/predicate.html Mon Mar 25 23:19:15 2013 @@ -137,8 +137,27 @@ from(
"jms:queue
Compound Predicates
-
You can also create compound predicates using boolean operators such as and, or, not and many others.
-The sample below demonstrates this:
+ +
You can also create compound predicates using boolean operators such as and, or, not and many others.
+ +
Currently this feature is only available in the Java-based DSLs, but not in the Spring nor Blueprint DSLs.
+ +
Using the PredicateBuilder class, you can combine predicates from different Expression Languages based on logical operators and comparison operators:
+ +
- not, and, or
- isNull, isNotNull
- isEqualTo, isGreaterThan, isLessThan
- startsWith, endsWith
- in ("any of X predicates stands true")
+ + +
Additionally, with PredicateBuilder you can create Regular Expressions and use them as predicates, applying them to the result of an expression, e.g. PredicateBuilder.regex(header("foo"), "\d{4}") applies the regular expression to the header = foo.
+ +
Combining different Expression Languages is also possible, e.g.:
+ +
+
```
+PredicateBuilder.and(XPathBuilder.xpath("/bookings/flights"), simple("${property.country = 'Spain'}"))
+
```
+
+ +
The sample below demonstrates further use cases:
```
// We define 3 predicates based on some user roles
 // we have static imported and/or from org.apache.camel.builder.PredicateBuilder
@@ -167,7 +186,6 @@ The sample below demonstrates this:
 
```
-
Extensible Predicates

Camel supports extensible Predicates using multiple Languages; the following languages are supported out of the box
- Bean Language for using Java for expressions
- Constant
- the unified EL from JSP and JSF
- Header
- JXPath
- Mvel
- OGNL
- Ref Language
- Property
- Scripting Languages such as @@ -198,7 +216,6 @@ The sample below demonstrates this:
  
  See Also
  - Expression
  -

Languages

Compound Predicates

Extensible Predicates

See Also