IBM BPM, V8.0.1, All platforms > Authoring services in Integration Designer > Advanced development topics > Adding Java to the application

Use Java in the assembly editor

Most of the time you deal with WSDL interfaces and references when working with components and imports in the assembly diagram. However, IBM Integration Designer supports some Javaâ„¢ functions and provides some ways for you to use Java components with your WSDL components. Java components, components with no implementation, and stand-alone references can have Java or WSDL interfaces in their partner references.

IBM Integration Designer is organized around the use of WSDL interfaces and references, but it does provide some ways to work with Java:

• You can create a Java component.

• You can add a Java reference to a Java component or stand-alone references to invoke a target service that has a matching WSDL interface. To help you with this action, you can convert a WSDL reference on a Java component or on stand-alone references to a Java reference.

• You can drag a Java class onto the assembly editor canvas as a component or drag an EJB (stateless session bean) as an import. The assembly editor can generate a map component that allows you to invoke the Java component or import from a WSDL component.

Limitations of Java components in mediation modules

• When you wire a mediation flow component to a Java component, the service message object is not propagated through the Java component. As a result, an import invoked via the Java component will not have any transport headers that are set inside the mediation flow component.

• You cannot wire a Java component's reference to the interface of a mediation flow component.

The topics listed below provide information about these processes.

• Create a Java component
  Although most components use SCA and WSDL interfaces, you can also create Java components and use them with SCA components and Java interfaces.
• SCA to Java bridge
  

  You cannot directly wire a component with a Web Services Definition Language (WSDL) type of reference to another component that has a Java interface, but there is a utility that helps you create a bridge component to make a WSDL to Java connection. The component is generated, so you do not have to write conversion code.

• Calling WSDL interfaces from Java references
  In top-down development, if you want a Java component or stand-alone references to invoke a component that has a WSDL interface, you do not need to create the Java reference manually. You can wire a Java component to a component with a WSDL interface. The assembly editor automatically adds a reference to the Java component.

  You can then choose to generate a Java interface for that reference that matches the WSDL interface on the other component. Otherwise, a WSDL interface will be generated for the reference.

• Calling Java interfaces from WSDL references
  Occasions might arise when you want to access a service with Java interfaces from a component that can only support WSDL references. However, you cannot directly draw a wire from a WSDL-typed reference to a Java component or a stateless session bean EJB import that has a Java interface. As well, most component implementations do not allow Java-typed references. The assembly editor provides an easy way of overcoming this difficulty.
• Overriding the generated Service Component Architecture implementation
  Sometimes, the conversion the system creates between a Java code and a Service Data Object (SDO) may not meet your needs. Use this procedure to replace the default SCA class implementation with your own.
• Overriding a Service Data Object (SDO) to Java conversion
  Sometimes, the conversion the system creates between a Service Data Object (SDO) and a Java type object may not meet your needs. Use this procedure to replace the default implementation with your own.
• Java to XML conversion
  The system generates XML based on Java types using predefined rules.

Adding Java to the application