try using defaulting of dropdownDescriptorSelector

core/src/main/java/hudson/tasks/Maven.java

@@ -38,8 +38,6 @@ import hudson.model.Computer;
 import hudson.model.EnvironmentSpecific;
 import hudson.model.Node;
 import jenkins.model.Jenkins;
-import jenkins.mvn.DefaultGlobalSettingsProvider;
-import jenkins.mvn.DefaultSettingsProvider;
 import jenkins.mvn.GlobalMavenConfig;
 import jenkins.mvn.GlobalSettingsProvider;
 import jenkins.mvn.SettingsProvider;
@@ -130,13 +128,13 @@ public class Maven extends Builder {
      * Provides access to the settings.xml to be used for a build.
      * @since 1.491
      */
-    private SettingsProvider settings = new DefaultSettingsProvider();
+    private SettingsProvider settings;
     
     /**
      * Provides access to the global settings.xml to be used for a build.
      * @since 1.491
      */
-    private GlobalSettingsProvider globalSettings = new DefaultGlobalSettingsProvider();
+    private GlobalSettingsProvider globalSettings;
 
     private final static String MAVEN_1_INSTALLATION_COMMON_FILE = "bin/maven";
     private final static String MAVEN_2_INSTALLATION_COMMON_FILE = "bin/mvn";
@@ -164,8 +162,8 @@ public class Maven extends Builder {
         this.properties = Util.fixEmptyAndTrim(properties);
         this.jvmOptions = Util.fixEmptyAndTrim(jvmOptions);
         this.usePrivateRepository = usePrivateRepository;
-        this.settings = settings;
-        this.globalSettings = globalSettings;
+        this.settings = settings != null ? settings : GlobalMavenConfig.get().getSettingsProvider();
+        this.globalSettings = globalSettings != null ? globalSettings : GlobalMavenConfig.get().getGlobalSettingsProvider();
     }
 
     public String getTargets() {
@@ -407,6 +405,14 @@ public class Maven extends Builder {
         public String getDisplayName() {
             return Messages.Maven_DisplayName();
         }
+        
+        public GlobalSettingsProvider getDefaultGlobalSettingsProvider() {
+            return GlobalMavenConfig.get().getGlobalSettingsProvider();
+        }
+        
+        public SettingsProvider getDefaultSettingsProvider() {
+            return GlobalMavenConfig.get().getSettingsProvider();
+        }
 
         public MavenInstallation[] getInstallations() {
             return installations;

core/src/main/resources/hudson/tasks/Maven/config.jelly

@@ -50,7 +50,8 @@ THE SOFTWARE.
     <f:entry field="usePrivateRepository" title="${%Use private Maven repository}" help="/plugin/maven-plugin/private-repository.html">
       <f:checkbox checked="${it.usesPrivateRepository()}" />
     </f:entry>
-    <f:dropdownDescriptorSelector title="${%Settings file}" descriptors="${descriptor.settingsProviders}" field="settings"/>
+    
+    <f:dropdownDescriptorSelector title="${%Settings file}"  field="settings" default="${descriptor.defaultSettingsProvider}"/>
 <!--
     <f:entry   help="/help/tasks/maven/maven-settings.html">
 
@@ -58,6 +59,6 @@ THE SOFTWARE.
     <f:entry   help="/help/tasks/maven/maven-settings.html">
     </f:entry>
 -->
-    <f:dropdownDescriptorSelector title="${%Global Settings file}" field="globalSettings" descriptors="${descriptor.globalSettingsProviders}"/>
+	<f:dropdownDescriptorSelector title="${%Global Settings file}" field="globalSettings"  default="${descriptor.defaultGlobalSettingsProvider}"/>    
   </f:advanced>
 </j:jelly>
\ No newline at end of file