Suchen

Dieser Inhalt ist in der von Ihnen ausgewählten Sprache nicht verfügbar.

Chapter 30. The Simple Language

download PDF

Abstract

The simple language is a language that was developed in Apache Camel specifically for the purpose of accessing and manipulating the various parts of an exchange object. The language is not quite as simple as when it was originally created and it now features a comprehensive set of logical operators and conjunctions.

30.1. Java DSL

Simple expressions in Java DSL

In the Java DSL, there are two styles for using the simple() command in a route. You can either pass the simple() command as an argument to a processor, as follows:
from("seda:order")
  .filter(simple("${in.header.foo}"))
  .to("mock:fooOrders");
Or you can call the simple() command as a sub-clause on the processor, for example:
from("seda:order")
  .filter()
  .simple("${in.header.foo}")
  .to("mock:fooOrders");

Embedding in a string

If you are embedding a simple expression inside a plain text string, you must use the placeholder syntax, ${Expression}. For example, to embed the in.header.name expression in a string:
simple("Hello ${in.header.name}, how are you?")

Customizing the start and end tokens

From Java, you can customize the start and end tokens ({ and }, by default) by calling the changeFunctionStartToken static method and the changeFunctionEndToken static method on the SimpleLanguage object.
For example, you can change the start and end tokens to [ and ] in Java, as follows:
// Java
import org.apache.camel.language.simple.SimpleLanguage;
...
SimpleLanguage.changeFunctionStartToken("[");
SimpleLanguage.changeFunctionEndToken("]");
Note
Customizing the start and end tokens affects all Apache Camel applications that share the same camel-core library on their classpath. For example, in an OSGi server this might affect many applications; whereas in a Web application (WAR file) it would affect only the Web application itself.
Red Hat logoGithubRedditYoutubeTwitter

Lernen

Testen, kaufen und verkaufen

Communitys

Über Red Hat Dokumentation

Wir helfen Red Hat Benutzern, mit unseren Produkten und Diensten innovativ zu sein und ihre Ziele zu erreichen – mit Inhalten, denen sie vertrauen können.

Mehr Inklusion in Open Source

Red Hat hat sich verpflichtet, problematische Sprache in unserem Code, unserer Dokumentation und unseren Web-Eigenschaften zu ersetzen. Weitere Einzelheiten finden Sie in Red Hat Blog.

Über Red Hat

Wir liefern gehärtete Lösungen, die es Unternehmen leichter machen, plattform- und umgebungsübergreifend zu arbeiten, vom zentralen Rechenzentrum bis zum Netzwerkrand.

© 2024 Red Hat, Inc.