[IGNITE-218]: IgfsUserContext corrected.
Project: http://git-wip-us.apache.org/repos/asf/incubator-ignite/repo Commit: http://git-wip-us.apache.org/repos/asf/incubator-ignite/commit/89457c41 Tree: http://git-wip-us.apache.org/repos/asf/incubator-ignite/tree/89457c41 Diff: http://git-wip-us.apache.org/repos/asf/incubator-ignite/diff/89457c41 Branch: refs/heads/ignite-218 Commit: 89457c4142e77509786c7da3594df961f79f79bd Parents: 091c904 Author: iveselovskiy <iveselovs...@gridgain.com> Authored: Thu Apr 16 13:48:47 2015 +0300 Committer: iveselovskiy <iveselovs...@gridgain.com> Committed: Thu Apr 16 13:48:47 2015 +0300 ---------------------------------------------------------------------- .../org/apache/ignite/igfs/IgfsUserContext.java | 69 ++++++++++++++++++++ 1 file changed, 69 insertions(+) ---------------------------------------------------------------------- http://git-wip-us.apache.org/repos/asf/incubator-ignite/blob/89457c41/modules/core/src/main/java/org/apache/ignite/igfs/IgfsUserContext.java ---------------------------------------------------------------------- diff --git a/modules/core/src/main/java/org/apache/ignite/igfs/IgfsUserContext.java b/modules/core/src/main/java/org/apache/ignite/igfs/IgfsUserContext.java new file mode 100644 index 0000000..83b6691 --- /dev/null +++ b/modules/core/src/main/java/org/apache/ignite/igfs/IgfsUserContext.java @@ -0,0 +1,69 @@ +package org.apache.ignite.igfs; + +import org.apache.ignite.*; +import org.apache.ignite.configuration.*; +import java.util.concurrent.*; + +/** + * Provides ability to execute IGFS code in a context of a specific user. + */ +public abstract class IgfsUserContext { + /** + * Thread local to hold the current user context. + */ + private static final ThreadLocal<String> userStackThreadLocal = new ThreadLocal<String>() { + @Override protected String initialValue() { + String dfltUser = FileSystemConfiguration.DFLT_USER_NAME; + + return dfltUser.intern(); + } + }; + + /** + * Executes given callable in the given user context. + * The main contract of this method is that {@link #currentUser()} method invoked + * inside 'cllbl' callable always returns 'user' this callable executed with. + * @param user the user name + * @param cllbl the callable to execute + * @param <T> The type of callable result. + * @return the result of + * @throws NullPointerException if 'user' or 'callble' is null + * @throws IgniteException if any Exception thrown from callable.call(). + * The contract is that if this method throws IgniteException, this IgniteException getCause() method + * must return exactly the Exception thrown from the callable. + */ + public static <T> T doAs(String user, final Callable<T> cllbl) { + user = user.intern(); + + final String ctxUser = userStackThreadLocal.get(); + + try { + //noinspection StringEquality + if (ctxUser == user) + return cllbl.call(); // correct context is already there + + userStackThreadLocal.set(user); + + try { + return cllbl.call(); + } + finally { + userStackThreadLocal.set(ctxUser); + } + } catch (Exception e) { + throw new IgniteException(e); + } + } + + /** + * Gets the current context user. + * If this method is invoked outside of any doAs(), it will return the default user + * name as defined in {@link FileSystemConfiguration#DFLT_USER_NAME}. + * Note that the returned user name is always interned, so + * you may compare the names using '==' reference equality. + * @return the current user, never null. + */ + public static String currentUser() { + return userStackThreadLocal.get(); + } +}
