liquibase.servicelocator.WebSpherePackageScanClassResolver Maven / Gradle / Ivy
package liquibase.servicelocator;
import liquibase.logging.LogType;
import java.io.IOException;
import java.net.URL;
import java.util.Enumeration;
/**
* WebSphere specific resolver to handle loading annotated resources in JAR files.
*/
public class WebSpherePackageScanClassResolver extends DefaultPackageScanClassResolver {
private final String resourcePath;
/**
* Constructor.
*
* @param resourcePath the fixed resource path to use for fetching camel jars in WebSphere.
*/
public WebSpherePackageScanClassResolver(String resourcePath) {
this.resourcePath = resourcePath;
}
/**
* Is the classloader from IBM and thus the WebSphere platform?
*
* @param loader the classloader
* @return true if IBM classloader, false otherwise.
*/
public static boolean isWebSphereClassLoader(ClassLoader loader) {
return loader.getClass().getName().startsWith("com.ibm");
}
/**
* Overloaded to handle specific problem with getting resources on the IBM WebSphere platform.
*
* WebSphere can not load resources if the resource to load is a folder name, such as a
* packagename, you have to explicit name a resource that is a file.
*
* @param loader the classloader
* @param packageName the packagename for the package to load
* @return URL's for the given package
* @throws java.io.IOException is thrown by the classloader
*/
@Override
protected Enumeration getResources(ClassLoader loader, String packageName) throws IOException {
// try super first, just in vase
Enumeration enumeration = super.getResources(loader, packageName);
if (!enumeration.hasMoreElements()) {
log.debug(LogType.LOG, "Using WebSphere workaround to load the camel jars with the annotated converters.");
// Special WebSphere trick to load a file that exists in the JAR and then let it go from there.
// The trick is that we just need the URL's for the .jars that contains the type
// converters that is annotated. So by searching for this resource WebSphere is able to find
// it and return the URL to the .jar file with the resource. Then the DefaultPackageScanClassResolver
// can take it from there and find the classes that are annotated.
enumeration = loader.getResources(resourcePath);
}
return enumeration;
}
}