Access third-party APIs from a Java EE application

By default, Java EE applications do not have access to the third-party APIs available in Liberty. To enable this access, the application must be configured in server.xml, or an included file.

In the following example, an application called Scholar needs access to the third-party APIs available in Liberty. The application also uses a common library called Alexandria. This library is located in...

Avoid trouble: Third-party APIs might not remain compatible after an upgrade.

See Liberty externals support.


Steps

  1. Configure class loading for the application so that the application can access the third-party APIs.

    Values for the apiTypeVisibility attribute...

      spec Public specification APIs available for both compile and run time
      ibm-api APIs available in Liberty.
      api Public APIs available for both compile and run time
      stable Stable third party specification APIs available by default for both compile and run time. Including third-party in the apiTypeVisibility attribute of the classloader element makes third-party APIs available.
      third-party Common usage for the prefix, +third-party, results in "spec, ibm-api, api, stable, third-party". The prefix, -api, results in "spec, ibm-api, stable".

    In server.xml, or an included file, configure the API type visibility... 

      <application 
    id="scholar" 
    name="Scholar" 
    type="ear" 
    location="scholar.ear">

  <classloader 
      apiTypeVisibility="spec, ibm-api, stable, third-party" 
      commonLibraryRef="Alexandria" />

</application>

    If a prefix of + or - is added to API types, those API types are added or removed, respectively, from the default set of API types. The +third-party prefix results in spec, ibm-api, api, stable, third-party. The -api prefix results in spec, ibm-api, stable.

    In server.xml, or an included file, configure the API type visibility by adding the following code: 

      <application 
    id="scholar" 
    name="Scholar" 
    type="ear" 
    location="scholar.ear">

  <classloader 
      apiTypeVisibility="+third-party, -api"  
      commonLibraryRef="Alexandria" /> 

</application>

  2. If the application uses any common libraries, set those libraries to use the same API type visibility setting.

    In server.xml, or an included file, add... 

      <library 
    id="Alexandria" 
    apiTypeVisibility="spec, ibm-api, stable, third-party" >

  <fileset 
      dir="${server.config.dir}/mylib/Alexandria" 
      includes="*.jar" 
      scanInterval="5s" />

</library>


Parent topic: Configure class loaders and libraries for Java EE applications


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