- Get the absolute path on connect and use that while the connection is on-line (which is ok as when the connection is not online a null was returned from getRootPath() anyway)

(cherry picked from commit 71600d8b)

In 1.509.2, probably due to a bad Groovy script:
java.lang.ClassCastException: hudson.model.Hudson cannot be cast to hudson.model.Slave
	at hudson.slaves.SlaveComputer.getNode(SlaveComputer.java:176)
	at hudson.slaves.SlaveComputer.getNode(SlaveComputer.java:92)
	at jenkins.model.Jenkins$9.compare(Jenkins.java:1547)
	at jenkins.model.Jenkins$9.compare(Jenkins.java:1543)
	at java.util.Arrays.mergeSort(Arrays.java:1270)
	at java.util.Arrays.mergeSort(Arrays.java:1282)
	at java.util.Arrays.mergeSort(Arrays.java:1282)
	at java.util.Arrays.mergeSort(Arrays.java:1282)
	at java.util.Arrays.mergeSort(Arrays.java:1282)
	at java.util.Arrays.mergeSort(Arrays.java:1282)
	at java.util.Arrays.mergeSort(Arrays.java:1282)
	at java.util.Arrays.sort(Arrays.java:1210)
	at jenkins.model.Jenkins.getComputers(Jenkins.java:1543)

null pointer exception. Instead we create a dummy launcher and return
that if it is unable to get the slave node.

System.nanos() returns a monotonically increasing value that is not related
to wallclock time. Use System.currentTimeMillis() instead.

Node monitoring should run in parallel to reduce the total round-trip
time in large instances.

(Could consider throwing IAE if it does not appear to be.
Cannot easily call getRootPath().absolutize() since that requires a connection.)

Introduce jenkins.slaves.WorkspaceLocator which allows extensions to override the location of the workspace.

fixed serving of JARs if running with hudson-dev:run which was broken since https://github.com/jenkinsci/jenkins/commit/a376eb5832a75d4fb840a9088b37a988582b0965

Just import changes, from hudson.model.Jenkins -> jenkins.model.Jenkins,
and Javadoc comments.
Signed-off-by: NNigel Magnay <nigel.magnay@gmail.com>

Signed-off-by: NNigel Magnay <nigel.magnay@gmail.com>

tasks.Mailer          from,subject,failureOnly,charset 1.10
model.Project         slave                            1.60
model.Descriptor      properties                       1.62
model.Slave           command,localFS                  1.69
model.AbstractProject enableRemoteTrigger              1.77
model.FingerprintMap  core                             1.91
If anyone still has very old XML with these, OldDataMonitor will
still handle it (as unreadable data instead of old data, and
with a bit more noise in the log).

git-svn-id: https://hudson.dev.java.net/svn/hudson/trunk/hudson/main@31911 71c3de6d-444a-0410-be80-ed276b4c234a

--Merged-in:------------------------------------------------------------
r27601 | mindless | 2010-02-16 20:21:50 -0800 (Tue, 16 Feb 2010) | 8 lines

Add OldDataMonitor for tracking loaded data that contained old deprecated data,
the Saveable objects that can be save()'ed to persist the data in its new format,
and the Hudson releases where these structure changes took place.
A "Manage Old Data" form explains how Hudson deals with migrating old data
(keeping downgrades possible), lists the old data, and allows upgrade of the data
files with changes up through a selected Hudson release.
Added calls of OldDataMonitor.report() for six old deprecated fields/data changes.

--Merged-in:------------------------------------------------------------
r27683 | mindless | 2010-02-19 11:43:40 -0800 (Fri, 19 Feb 2010) | 5 lines

Expand OldDataMonitor to also track unreadable data found while loading.
These are reported from util.RobustReflectionConverter and RobustCollectionConverter.
"Manage Old Data" screen has additional text about unreadable data, and a form
to resave those files which will discard that data.

--Merged-in:------------------------------------------------------------
r27715 | mindless | 2010-02-20 08:56:51 -0800 (Sat, 20 Feb 2010) | 3 lines

Add Saveable/Item/Run listeners to remove entries tracked by OldDataMonitor
if they are resaved or deleted.

--Merged-in:------------------------------------------------------------
r27970 | mindless | 2010-02-26 09:02:43 -0800 (Fri, 26 Feb 2010) | 6 lines

Add OldDataMonitor reporting for deprecated fields in Mailer and HudsonPrivateSecurityRealm.
Includes fix in RobustReflectionConverter to report against outermost Saveable object
(User object can contain MyViewsProperty which is also Saveable).
Also added XStream2.PassthruConverter which is used to report old data during
unmarshalling when the containing Saveable is not known.

--Merged-in:------------------------------------------------------------
r27982 | mindless | 2010-02-26 11:35:41 -0800 (Fri, 26 Feb 2010) | 3 lines

Fix to show username for User objects instead of "fullDisplayName".
Also increased threshold for possible compatibility removal from 100 to 150 releases.

--Merged-in:------------------------------------------------------------
r27983 | mindless | 2010-02-26 11:43:06 -0800 (Fri, 26 Feb 2010) | 5 lines

Add OldDataMonitor reporting for ParametersAction.build, CauseAction.cause
and UpstreamCause.upstreamCause.
Note: these will make the list of objects on the OldData/manage screen very long
for Hudson installs with lots of builds run on Hudson 1.283 to 1.287.

--Merged-in:------------------------------------------------------------
r27987 | mindless | 2010-02-26 12:33:59 -0800 (Fri, 26 Feb 2010) | 4 lines

Refactored XStream2.PassthruConverter so uses do not need to be registered with
the XStream2 instance, but work for all XStream2 (using ConverterImpl subclass
found by AssociatedConverterImpl).

--Merged-in:------------------------------------------------------------
r27989 | mindless | 2010-02-26 13:38:35 -0800 (Fri, 26 Feb 2010) | 3 lines

Add a cache of ConverterImpl instances in AssociatedConverterImpl to avoid
repeated work in findConverter every time such an object is marshalled/unmarshalled.

--Merged-in:------------------------------------------------------------
r27996 | mindless | 2010-02-26 16:47:19 -0800 (Fri, 26 Feb 2010) | 2 lines

Add OldDataMonitor reporting for HealthReport.description

--Merged-in:------------------------------------------------------------
r27997 | mindless | 2010-02-26 16:49:28 -0800 (Fri, 26 Feb 2010) | 5 lines

Remove readResolve() in 3 classes where a Converter now does that work.
In GlobalMatrixAuthorizationStrategy and AuthorizationMatrixProperty also
add unreadable-data reporting when unable to parse a permission type,
and report when Item.READ permission is added for migration from < 1.301

--Merged-in:------------------------------------------------------------
r28073 | mindless | 2010-02-28 23:18:06 -0800 (Sun, 28 Feb 2010) | 5 lines

Report any old XStream 1.1.x serialized (files from Hudson before 1.106)
to OldDataMonitor, using a ThreadLocal since the unmarshal context is not
available in the mapper.  These use "-" to encode "$" in a class name
instead of "_-" used now.

+-End-of-merged-revisions----------------------------------------------+



git-svn-id: https://hudson.dev.java.net/svn/hudson/trunk/hudson/main@28147 71c3de6d-444a-0410-be80-ed276b4c234a

git-svn-id: https://hudson.dev.java.net/svn/hudson/trunk/hudson/main@28020 71c3de6d-444a-0410-be80-ed276b4c234a

https://svn.dev.java.net/svn/hudson/branches/rc

........
  r25543 | kohsuke | 2010-01-08 13:52:04 -0800 (Fri, 08 Jan 2010) | 1 line
  
  added a hidden switch to control the 'workspace' name.
........


git-svn-id: https://hudson.dev.java.net/svn/hudson/trunk/hudson/main@25544 71c3de6d-444a-0410-be80-ed276b4c234a

git-svn-id: https://hudson.dev.java.net/svn/hudson/trunk/hudson/main@22558 71c3de6d-444a-0410-be80-ed276b4c234a

[HUDSON-4531] extension point without a descriptor is now reported with more information for a better troubleshooting.

git-svn-id: https://hudson.dev.java.net/svn/hudson/trunk/hudson/main@22098 71c3de6d-444a-0410-be80-ed276b4c234a

git-svn-id: https://hudson.dev.java.net/svn/hudson/trunk/hudson/main@21863 71c3de6d-444a-0410-be80-ed276b4c234a

git-svn-id: https://hudson.dev.java.net/svn/hudson/trunk/hudson/main@21655 71c3de6d-444a-0410-be80-ed276b4c234a

git-svn-id: https://hudson.dev.java.net/svn/hudson/trunk/hudson/main@21557 71c3de6d-444a-0410-be80-ed276b4c234a

  task or even slave related.
- Removes all caching of labels. Slow extensions can cache (see nodetags).
- Pulls up common implementations of getAssignedLabels and an immutable
  getDynamicLabels facility into Node. getDynamicLabels was previously public,
  but never exported.
- factored out some trivially duplicated code into Node.getHudsonlabel
- changes LabelFinder to return Collection<Label> as that is the data that
  higher layers want to work with, and there is no good reason to force lookups
  when implementations can and should cache themselves.
- Deletes OSLabeler, a disabled version of the LabelFinder extension point -
  there is no need for dead code to be keep in the tree.


git-svn-id: https://hudson.dev.java.net/svn/hudson/trunk/hudson/main@21160 71c3de6d-444a-0410-be80-ed276b4c234a

git-svn-id: https://hudson.dev.java.net/svn/hudson/trunk/hudson/main@20900 71c3de6d-444a-0410-be80-ed276b4c234a

git-svn-id: https://hudson.dev.java.net/svn/hudson/trunk/hudson/main@20878 71c3de6d-444a-0410-be80-ed276b4c234a

git-svn-id: https://hudson.dev.java.net/svn/hudson/trunk/hudson/main@20863 71c3de6d-444a-0410-be80-ed276b4c234a