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Variable	Type	Description
exchangeId	String	Camel 2.3: the exchange id
id	String	the input message id
body	Object	the input body
in.body	Object	the input body
body.OGNL	Object	Camel 2.3: the input body invoked using a Camel OGNL expression.
in.body.OGNL	Object	Camel 2.3: the input body invoked using a Camel OGNL expression.
bodyAs(type)	Type	Camel 2.3: Converts the body to the given type determined by its classname. The converted body can be null.
mandatoryBodyAs(type)	Type	Camel 2.5: Converts the body to the given type determined by its classname, and expects the body to be not null.
out.body	Object	the output body
header.foo	Object	refer to the input foo header
headers.foo	Object	refer to the input foo header
in.header.foo	Object	refer to the input foo header
in.headers.foo	Object	refer to the input foo header
<ac:structured-macro ac:name="unmigrated-wiki-markup" ac:schema-version="1" ac:macro-id="93fb5149473d7164-3654053d-49c34989-bbf48372-2332002283d46af6c8064b62"><ac:plain-text-body><![CDATA[	header.foo[bar]	Object	Camel 2.3: regard input foo header as a map and perform lookup on the map with bar as key	]]></ac:plain-text-body></ac:structured-macro>
<ac:structured-macro ac:name="unmigrated-wiki-markup" ac:schema-version="1" ac:macro-id="0fa2f1b6275de1ee-fd909fb4-434548b2-983e9a5d-f808faf581c2810eee12c5e7"><ac:plain-text-body><![CDATA[	in.header.foo[bar]	Object	Camel 2.3: regard input foo header as a map and perform lookup on the map with bar as key	]]></ac:plain-text-body></ac:structured-macro>
<ac:structured-macro ac:name="unmigrated-wiki-markup" ac:schema-version="1" ac:macro-id="10c5f86175d9ecdf-e0c5bc4c-47614137-97a29438-8581b3a7c298eb4db4aa078e"><ac:plain-text-body><![CDATA[	in.headers.foo[bar]	Object	Camel 2.3: regard input foo header as a map and perform lookup on the map with bar as key	]]></ac:plain-text-body></ac:structured-macro>
header.foo.OGNL	Object	Camel 2.3: refer to the input foo header and invoke its value using a Camel OGNL expression.
in.header.foo.OGNL	Object	Camel 2.3: refer to the input foo header and invoke its value using a Camel OGNL expression.
in.headers.foo.OGNL	Object	Camel 2.3: refer to the input foo header and invoke its value using a Camel OGNL expression.
out.header.foo	Object	refer to the out header foo
out.headers.foo	Object	refer to the out header foo
headerAs(key,type)	Type	Camel 2.5: Converts the header to the given type determined by its classname
property.foo	Object	refer to the foo property on the exchange
property.foo.OGNL	Object	Camel 2.8: refer to the foo property on the exchange and invoke its value using a Camel OGNL expression.
sys.foo	String	refer to the system property
sysenv.foo	String	Camel 2.3: refer to the system environment
exception	Object	Camel 2.4: Refer to the exception object on the exchange, is null if no exception set on exchange. Will fallback and grab caught exceptions (`Exchange.EXCEPTION_CAUGHT`) if the Exchange has any.
exception.OGNL	Object	Camel 2.4: Refer to the exchange exception invoked using a Camel OGNL expression object
exception.message	String	Camel 2.0. Refer to the exception.message on the exchange, is null if no exception set on exchange. Will fallback and grab caught exceptions (`Exchange.EXCEPTION_CAUGHT`) if the Exchange has any.
exception.stacktrace	String	Camel 2.6. Refer to the exception.stracktrace on the exchange, is null if no exception set on exchange. Will fallback and grab caught exceptions (`Exchange.EXCEPTION_CAUGHT`) if the Exchange has any.
date:command:pattern	String	Camel 1.5. Date formatting using the `java.text.SimpleDataFormat` patterns. Supported commands are: now for current timestamp, in.header.xxx or header.xxx to use the Date object in the IN header with the key xxx. out.header.xxx to use the Date object in the OUT header with the key xxx.
bean:bean expression	Object	Camel 1.5. Invoking a bean expression using the Bean language. Specifying a method name you must use dot as separator. In Camel 2.0 we also support the ?method=methodname syntax that is used by the Bean component.
properties:locations:key	String	Camel 2.3: Lookup a property with the given key. The `locations` option is optional. See more at Using PropertyPlaceholder.
threadName	String	Camel 2.3: Returns the name of the current thread. Can be used for logging purpose.
ref:xxx	Object	Camel 2.6: To lookup a bean from the Registry with the given id.

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Where the rightValue can be a String literal enclosed in ' ', null, a constant value or another expression enclosed in ${ }.
Camel will automatically type convert the rightValue type to the leftValue type, so its able to eg. convert a string into a numeric so you can use > comparison for numeric values.

The following operators is are supported:

Operator	Description
==	equals
>	greater than
>=	greater than or equals
<	less than
<=	less than or equals
!=	not equals
contains	For testing if contains in a string based value
not contains	For testing if not contains in a string based value
regex	For matching against a given regular expression pattern defined as a String value
not regex	For not matching against a given regular expression pattern defined as a String value
in	For matching if in a set of values, each element must be separated by comma.
not in	For matching if not in a set of values, each element must be separated by comma.
is	For matching if the left hand side type is an instanceof the value.
not is	For matching if the left hand side type is not an instanceof the value.
range	For matching if the left hand side is within a range of values defined as numbers: `from..to`
not range	For matching if the left hand side is not within a range of values defined as numbers: `from..to`

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Info

title	Comparing with different types

When you compare with different types such as String and int, then you have to take a bit care. Camel will use the type from the left hand side as 1st priority. And fallback to the right hand side type if both values couldn't be compared based on that type.
This means you can flip the values to enforce a specific type. Suppose the bar value above is a String. Then you can flip the equation:

Code Block
simple("100 < ${in.header.bar}")

which then ensures the int type is used as 1st priority.

This may change in the future if the Camel team improves and let the binary comparision comparison operations be smarter and to prefer numeric types over String based. It's most often the String type which causes problem when comparing with numbers.

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Code Block
simple("${in.header.type} not in 'gold,silver'")

And you can test for if the type is a certain instance, eg for instance a String

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Code Block
simple("${in.header.type} is String")

Ranges is are also supported. The range interval requires numbers and both from and end is are inclusive. For instance to test whether a value is between 100 and 199:

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Tip

title	Can be used in Spring XML

As the Spring XML does not have all the power as the Java DSL with all its various builder methods, you had have to resort to use some other languages
for testing with simple operators. Now you can do this with the simple language. In the sample below we want to test if the header is a widget order:

Code Block

	xml
	xml

    <from uri="seda:orders">
       <filter>
           <simple>${in.header.type} == 'widget'</simple>
           <to uri="bean:orderService?method=handleWidget"/>
       </filter>
    </from>

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And of course the or is also supported. The sample example would be:

Code Block
simple("${in.header.title} contains 'Camel' or ${in.header.type'} == 'gold'")

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Notice that we must use ${ } placeholders in the expression now to let allow Camel be able to parse it correctly.

And this sample uses the date command to output current date.

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Code Block

	xml
	xml

  <transform>
    <simple>Hello ${bodyAs(String)} how are you?</simple>
  </transform>

There is are a few types which have a shorthand notation, hence why so we can use String instead of java.lang.String. These are: byte[], String, Integer, Long. All other types must use their FQN name, e.g. org.w3c.dom.Document.

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In the code above we lookup the header with name type and regard it as a java.util.Map and we then lookup with the key gold and return the value.
If the header is not convertible to Map an exception is thrown. If the header with name type does not exists exist null is returned.

Dependencies

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