improved OO-ness by using ClockDifference.

git-svn-id: https://hudson.dev.java.net/svn/hudson/trunk/hudson/main@3920 71c3de6d-444a-0410-be80-ed276b4c234a

core/pom.xml

@@ -222,7 +222,7 @@
     <dependency>
       <groupId>org.kohsuke.stapler</groupId>
       <artifactId>stapler</artifactId>
-      <version>1.40</version>
+      <version>1.41-SNAPSHOT</version>
     </dependency>
     <dependency>
       <groupId>org.kohsuke</groupId>

core/src/main/java/hudson/model/Hudson.java

@@ -44,6 +44,7 @@ import hudson.util.CopyOnWriteMap;
 import hudson.util.FormFieldValidator;
 import hudson.util.MultipartFormDataParser;
 import hudson.util.XStream2;
+import hudson.util.ClockDifference;
 import org.apache.commons.fileupload.FileItem;
 import org.apache.commons.fileupload.disk.DiskFileItemFactory;
 import org.apache.commons.fileupload.servlet.ServletFileUpload;
@@ -713,8 +714,8 @@ public final class Hudson extends View implements ItemGroup<TopLevelItem>, Node
         return new FilePath(new File(item.getRootDir(),"workspace"));
     }
 
-    public long getClockDifference() throws IOException {
-        return 0;
+    public ClockDifference getClockDifference() {
+        return ClockDifference.ZERO;
     }
 
     public boolean isUseSecurity() {

core/src/main/java/hudson/model/Node.java

@@ -4,6 +4,7 @@ import hudson.Launcher;
 import hudson.FilePath;
 import hudson.node_monitors.NodeMonitor;
 import hudson.util.EnumConverter;
+import hudson.util.ClockDifference;
 import org.apache.commons.beanutils.ConvertUtils;
 
 import java.util.Set;
@@ -81,13 +82,11 @@ public interface Node {
      * Estimates the clock difference with this slave.
      *
      * @return
-     *      difference in milli-seconds.
-     *      a positive value indicates that the master is ahead of the slave,
-     *      and negative value indicates otherwise.
+     *      always non-null.
      * @throws InterruptedException
      *      if the operation is aborted.
      */
-    long getClockDifference() throws IOException, InterruptedException;
+    ClockDifference getClockDifference() throws IOException, InterruptedException;
 
     public enum Mode {
         NORMAL("Utilize this slave as much as possible"),

core/src/main/java/hudson/model/Slave.java

@@ -18,6 +18,7 @@ import hudson.util.NullStream;
 import hudson.util.RingBufferLogHandler;
 import hudson.util.StreamCopyThread;
 import hudson.util.StreamTaskListener;
+import hudson.util.ClockDifference;
 import org.kohsuke.stapler.StaplerRequest;
 import org.kohsuke.stapler.StaplerResponse;
 
@@ -222,9 +223,9 @@ public final class Slave implements Node, Serializable {
         return Hudson.getInstance().getLabel(name);
     }
 
-    public long getClockDifference() throws IOException, InterruptedException {
+    public ClockDifference getClockDifference() throws IOException, InterruptedException {
         VirtualChannel channel = getComputer().getChannel();
-        if(channel==null)   return 0;   // can't check
+        if(channel==null)   return null;   // can't check
 
         long startTime = System.currentTimeMillis();
         long slaveTime = channel.call(new Callable<Long,RuntimeException>() {
@@ -234,36 +235,7 @@ public final class Slave implements Node, Serializable {
         });
         long endTime = System.currentTimeMillis();
 
-        return (startTime+endTime)/2 - slaveTime;
-    }
-
-
-    /**
-     * Gets the clock difference in HTML string.
-     */
-    public String getClockDifferenceString() {
-        try {
-            long diff = getClockDifference();
-            if(-1000<diff && diff <1000)
-                return "In sync";  // clock is in sync
-
-            long abs = Math.abs(diff);
-
-            String s = Util.getTimeSpanString(abs);
-            if(diff<0)
-                s += " ahead";
-            else
-                s += " behind";
-
-            if(abs>100*60) // more than a minute difference
-                s = "<span class='error'>"+s+"</span>";
-
-            return s;
-        } catch (IOException e) {
-            return "<span class='error'>Unable to check</span>";
-        } catch (InterruptedException e) {
-            return "<span class='error'>Unable to check</span>";
-        }
+        return new ClockDifference((startTime+endTime)/2 - slaveTime);
     }
 
     public Computer createComputer() {

core/src/main/java/hudson/util/ClockDifference.java

 package hudson.util;
 
 import hudson.Util;
+import hudson.model.Node;
+
+import java.io.IOException;
 
 /**
  * Represents a clock difference. Immutable.
@@ -50,4 +53,27 @@ public final class ClockDifference {
         if(isDangerous())   s = "<span class=error>"+s+"</span>";
         return s;
     }
+
+    public static String toHtml(Node d) {
+        try {
+            return d.getClockDifference().toHtml();
+        } catch (IOException e) {
+            return FAILED_HTML;
+        } catch (InterruptedException e) {
+            return FAILED_HTML;
+        }
+    }
+
+    /**
+     * Gets the clock difference in HTML string.
+     * This version handles null {@link ClockDifference}.
+     */
+    public static String toHtml(ClockDifference d) {
+        if(d==null)     return FAILED_HTML;
+        return d.toHtml();
+    }
+
+    public static final ClockDifference ZERO = new ClockDifference(0);
+
+    private static final String FAILED_HTML = "<span class='error'>Failed to heck</span>";
 }