Chapter 23. MVEL

Overview
复制链接

MVEL is a Java-based dynamic language that is similar to OGNL, but is reported to be much faster. The MVEL support is in the camel-mvel module.

Syntax
复制链接

You use the MVEL dot syntax to invoke Java methods, for example:

getRequest().getBody().getFamilyName()

getRequest().getBody().getFamilyName()

Copy to Clipboard

Toggle word wrap

Because MVEL is dynamically typed, it is unnecessary to cast the message body instance (of Object type) before invoking the getFamilyName() method. You can also use an abbreviated syntax for invoking bean attributes, for example:

request.body.familyName

request.body.familyName

Copy to Clipboard

Toggle word wrap

Adding the MVEL module
复制链接

To use MVEL in your routes you need to add a dependency on camel-mvel to your project as shown in Example 23.1, “Adding the camel-mvel dependency”.

Example 23.1. Adding the camel-mvel dependency

<!-- Maven POM File -->
<properties>
  <camel-version>2.21.0.fuse-720050-redhat-00001</camel-version>
  ...
</properties>

<dependencies>
  ...
  <dependency>
    <groupId>org.apache.camel</groupId>
    <artifactId>camel-mvel</artifactId>
    <version>${camel-version}</version>
  </dependency>
  ...
</dependencies>

<!-- Maven POM File -->
<properties>
  <camel-version>2.21.0.fuse-720050-redhat-00001</camel-version>
  ...
</properties>

<dependencies>
  ...
  <dependency>
    <groupId>org.apache.camel</groupId>
    <artifactId>camel-mvel</artifactId>
    <version>${camel-version}</version>
  </dependency>
  ...
</dependencies>

Copy to Clipboard

Toggle word wrap

Built-in variables
复制链接

Table 23.1, “MVEL variables” lists the built-in variables that are accessible when using MVEL.

Expand

Table 23.1. MVEL variables
Name	Type	Description
`this`	`org.apache.camel.Exchange`	The current Exchange
`exchange`	`org.apache.camel.Exchange`	The current Exchange
`exception`	`Throwable`	the Exchange exception (if any)
`exchangeID`	`String`	the Exchange ID
`fault`	`org.apache.camel.Message`	The Fault message(if any)
`request`	`org.apache.camel.Message`	The IN message
`response`	`org.apache.camel.Message`	The OUT message
`properties`	`Map`	The Exchange properties
`property(name)`	`Object`	The value of the named Exchange property
`property(name, type)`	`Type`	The typed value of the named Exchange property

Example
复制链接

Example 23.2, “Route using MVEL” shows a route that uses MVEL.

Example 23.2. Route using MVEL

<camelContext>
  <route>
    <from uri="seda:foo"/>
    <filter>
      <language langauge="mvel">request.headers.foo == 'bar'</language>
      <to uri="seda:bar"/>
    </filter>
  </route>
</camelContext>

<camelContext>
  <route>
    <from uri="seda:foo"/>
    <filter>
      <language langauge="mvel">request.headers.foo == 'bar'</language>
      <to uri="seda:bar"/>
    </filter>
  </route>
</camelContext>

Copy to Clipboard

Toggle word wrap

此内容没有您所选择的语言版本。

Overview
复制链接

Syntax
复制链接

Adding the MVEL module
复制链接

Built-in variables
复制链接

Example
复制链接

学习

尝试、购买和销售

社区

关于红帽文档

让开源更具包容性

關於紅帽

Theme

Red Hat legal and privacy links

Red Hat legal and privacy links

此内容没有您所选择的语言版本。

Chapter 23. MVEL

Overview复制链接链接已复制到粘贴板!

Syntax复制链接链接已复制到粘贴板!

Adding the MVEL module复制链接链接已复制到粘贴板!

Built-in variables复制链接链接已复制到粘贴板!

Example复制链接链接已复制到粘贴板!

学习

尝试、购买和销售

社区

关于红帽文档

让开源更具包容性

關於紅帽

Theme

Red Hat legal and privacy links

Red Hat legal and privacy links

Overview
复制链接

Syntax
复制链接

Adding the MVEL module
复制链接

Built-in variables
复制链接

Example
复制链接