diff --git a/core/src/main/java/hudson/Util.java b/core/src/main/java/hudson/Util.java
index fe4334438e739335e818f34ad7c5a969b8525fa2..7775b4ca6afe4361266670c997ec4f7031f602f9 100644
--- a/core/src/main/java/hudson/Util.java
+++ b/core/src/main/java/hudson/Util.java
@@ -23,6 +23,7 @@
  */
 package hudson;
 
+import edu.umd.cs.findbugs.annotations.SuppressFBWarnings;
 import hudson.model.TaskListener;
 import jenkins.util.MemoryReductionUtil;
 import hudson.util.QuotedStringTokenizer;
@@ -692,6 +693,7 @@ public class Util {
      *      number of milliseconds.
      */
     @Nonnull
+    @SuppressFBWarnings(value = "ICAST_IDIV_CAST_TO_DOUBLE", justification = "We want to truncate here.")
     public static String getTimeSpanString(long duration) {
         // Break the duration up in to units.
         long years = duration / ONE_YEAR_MS;
diff --git a/core/src/main/java/hudson/cli/DisablePluginCommand.java b/core/src/main/java/hudson/cli/DisablePluginCommand.java
index 101576e90442b3b20c901563bfb356b02364ac83..70b4806f99fc9570572c7b36c56e8b6dad91256c 100644
--- a/core/src/main/java/hudson/cli/DisablePluginCommand.java
+++ b/core/src/main/java/hudson/cli/DisablePluginCommand.java
@@ -220,15 +220,15 @@ public class DisablePluginCommand extends CLICommand {
                 break;
             case NO_SUCH_PLUGIN:
                 returnCode = RETURN_CODE_NO_SUCH_PLUGIN;
-        }
-
-        if (returnCode == 0) {
-            for (PluginWrapper.PluginDisableResult oneDependentResult : result.getDependentsDisableStatus()) {
-                returnCode = getResultCode(oneDependentResult);
-                if (returnCode != 0) {
-                    break;
+                break; 
+            default:
+                for (PluginWrapper.PluginDisableResult oneDependentResult : result.getDependentsDisableStatus()) {
+                    returnCode = getResultCode(oneDependentResult);
+                    if (returnCode != 0) {
+                        break;
+                    }
                 }
-            }
+                break;
         }
 
         return returnCode;
diff --git a/core/src/main/java/hudson/model/Queue.java b/core/src/main/java/hudson/model/Queue.java
index 3a8be8a72940b36af74a434af789b8e3bd13cbc7..5606dbd701373840f4d90895bc7adad66cf793b1 100644
--- a/core/src/main/java/hudson/model/Queue.java
+++ b/core/src/main/java/hudson/model/Queue.java
@@ -2417,6 +2417,7 @@ public class Queue extends ResourceController implements Saveable {
      */
     @Restricted(NoExternalUse.class)
     @ExportedBean(defaultVisibility = 999)
+    @SuppressFBWarnings(value = "URF_UNREAD_PUBLIC_OR_PROTECTED_FIELD", justification = "it is exported, so it might be used")
     public class StubItem {
 
         @Exported public StubTask task;
diff --git a/core/src/main/java/hudson/model/UpdateCenter.java b/core/src/main/java/hudson/model/UpdateCenter.java
index 68aa6f3f2593a1770844a486e507285568ae4017..f1d4dd79ce6da9bc6cb4196b0ce9493cb89de4a4 100644
--- a/core/src/main/java/hudson/model/UpdateCenter.java
+++ b/core/src/main/java/hudson/model/UpdateCenter.java
@@ -1999,11 +1999,14 @@ public class UpdateCenter extends AbstractModelObject implements Saveable, OnMas
                 return;
             case FAIL:
                 throwVerificationFailure(entry.getSha512(), job.getComputedSHA512(), file, "SHA-512");
+                break;
             case NOT_COMPUTED:
                 LOGGER.log(WARNING, "Attempt to verify a downloaded file (" + file.getName() + ") using SHA-512 failed since it could not be computed. Falling back to weaker algorithms. Update your JRE.");
                 break;
             case NOT_PROVIDED:
                 break;
+            default:
+                throw new IllegalStateException("Unexpected value: " + result512);
         }
 
         VerificationResult result256 = verifyChecksums(entry.getSha256(), job.getComputedSHA256(), false);
@@ -2012,9 +2015,12 @@ public class UpdateCenter extends AbstractModelObject implements Saveable, OnMas
                 return;
             case FAIL:
                 throwVerificationFailure(entry.getSha256(), job.getComputedSHA256(), file, "SHA-256");
+                break;
             case NOT_COMPUTED:
             case NOT_PROVIDED:
                 break;
+            default:
+                throw new IllegalStateException("Unexpected value: " + result256);
         }
 
         if (result512 == VerificationResult.NOT_PROVIDED && result256 == VerificationResult.NOT_PROVIDED) {
@@ -2027,6 +2033,7 @@ public class UpdateCenter extends AbstractModelObject implements Saveable, OnMas
                 return;
             case FAIL:
                 throwVerificationFailure(entry.getSha1(), job.getComputedSHA1(), file, "SHA-1");
+                break;
             case NOT_COMPUTED:
                 throw new IOException("Failed to compute SHA-1 of downloaded file, refusing installation");
             case NOT_PROVIDED:
diff --git a/core/src/main/java/hudson/util/jna/SHELLEXECUTEINFO.java b/core/src/main/java/hudson/util/jna/SHELLEXECUTEINFO.java
index 506242c9aaa0207358125dfbd7055d150c94bd5d..0bfc5e627ff74db0ab0539bd06e1cae123a54bb7 100644
--- a/core/src/main/java/hudson/util/jna/SHELLEXECUTEINFO.java
+++ b/core/src/main/java/hudson/util/jna/SHELLEXECUTEINFO.java
@@ -57,7 +57,8 @@ typedef struct _SHELLEXECUTEINFO {
  * @author Kohsuke Kawaguchi
  * @see <a href="http://msdn.microsoft.com/en-us/library/bb759784(v=VS.85).aspx">MSDN: SHELLEXECUTEINFO</a>
  */
-@SuppressFBWarnings(value = "UUF_UNUSED_PUBLIC_OR_PROTECTED_FIELD", justification = "JNA Data Structure")
+@SuppressFBWarnings(value = {"UUF_UNUSED_PUBLIC_OR_PROTECTED_FIELD", "URF_UNREAD_PUBLIC_OR_PROTECTED_FIELD"}, 
+        justification = "JNA Data Structure")
 public class SHELLEXECUTEINFO extends Structure {
     public int cbSize = size();
     public int fMask;
@@ -87,7 +88,8 @@ public class SHELLEXECUTEINFO extends Structure {
                 "hProcess");
     }
 
-    @SuppressFBWarnings(value = "UUF_UNUSED_PUBLIC_OR_PROTECTED_FIELD", justification = "JNA Data Structure")
+    @SuppressFBWarnings(value = {"UUF_UNUSED_PUBLIC_OR_PROTECTED_FIELD", "URF_UNREAD_PUBLIC_OR_PROTECTED_FIELD"}, 
+            justification = "JNA Data Structure")
     public static class DUMMYUNIONNAME_union extends Union {
         public Pointer hIcon;
         public Pointer hMonitor;