Managing applications - OSGi in Action - page 327

Listing 10.2 OBR repository shell command example

public class RepositoryCommand extends BasicCommand {
public void exec(String args, PrintStream out, PrintStream err)
throws Exception {
args = args.trim();
RepositoryAdmin admin = getRepositoryAdmin();
if (admin != null) {
if ("list-urls".equalsIgnoreCase(args)) {
for (Repository repo : admin.listRepositories()) {
out.println(repo.getName() + " (" + repo.getURL() + ")");
}
} else if (args != null) {
if (args.startsWith("add-url")) {
admin.addRepository(
new URL(args.substring("add-url".length())));
} else if (args.startsWith("remove-url")) {
admin.removeRepository(
new URL(args.substring("remove-url".length())));
} else if (args.startsWith("list")) {
String query = (args.equals("list"))
? "(symbolicname=*)"
: args.substring("list".length()).trim();
for (Resource res : admin.discoverResources(query)) {
out.println(res.getPresentationName() + " ("
+ res.getSymbolicName() + ") " + res.getVersion());
}
}
} else {
out.println(
"Unknown command - use {list-urls|add-url|remove-url|list}");
}
} else {
out.println("No RepositoryAdmin service found...");
}
}

B

Lists
repositories

D Removes
repository

E

Discovers
resources

private RepositoryAdmin getRepositoryAdmin() {
...
}
}
The obr-repo command has the following subcommands: list-url , add-url ,
remove-url , and list . A RepositoryAdmin provides access to a number of reposito-
ries referenced by URL s. You implement the list-url subcommand B to list these
repositories by retrieving the RepositoryAdmin service and calling its listReposito-
ries() method, which gives you access to the associated Repository objects. In this
case, you loop through the repositories and print their names and URL s.
You can add or remove repository URL s with the add-url and remove-url subcom-
mands, respectively. As you can see at C and D , there's a one-to-one mapping to the
addRepository() and removeRepository() methods of the RepositoryAdmin service.
Finally, the list subcommand expects an LDAP query which it passes to discover-
Repositories() to discover resources E . If no query is specified, all resources are