Code clean up.

core/src/test/java/hudson/UtilTest.java

@@ -599,9 +599,7 @@ public class UtilTest {
 
     @Test
     public void ifOverriddenFailure() {
-        AbstractMethodError error = Assert.assertThrows(AbstractMethodError.class, () -> {
-            Util.ifOverridden(() -> true, BaseClass.class, DerivedClassFailure.class, "method");
-        });
+        AbstractMethodError error = Assert.assertThrows(AbstractMethodError.class, () -> Util.ifOverridden(() -> true, BaseClass.class, DerivedClassFailure.class, "method"));
         assertEquals("The class " + DerivedClassFailure.class.getName() + " must override at least one of the BaseClass.method methods", error.getMessage());
     }
 

core/src/test/java/hudson/XmlFileTest.java

@@ -42,7 +42,7 @@ public class XmlFileTest {
 
         XmlFile xmlFile =  new XmlFile(xs, new File(configUrl.getFile()));
         if (xmlFile.exists()) {
-            assertThrows(SAXParseException.class, () -> xmlFile.read());
+            assertThrows(SAXParseException.class, xmlFile::read);
         }
     }
 

core/src/test/java/jenkins/RemotingJarSignatureTest.java

@@ -1,7 +1,6 @@
 package jenkins;
 
 import static org.junit.Assert.assertNotNull;
-import static org.junit.Assert.fail;
 
 import hudson.remoting.Channel;
 import hudson.remoting.Which;

core/src/test/java/jenkins/util/JenkinsJVMTest.java

@@ -13,14 +13,14 @@ public class JenkinsJVMTest {
 
     @Test
     public void checkJenkinsJVM_WhenNotInAJenkinsJVM() {
-        assertThrows(IllegalStateException.class, () -> JenkinsJVM.checkJenkinsJVM());
+        assertThrows(IllegalStateException.class, JenkinsJVM::checkJenkinsJVM);
     }
 
     @Test
     public void checkNotJenkinsJVM_WhenInAJenkinsJVM() {
         JenkinsJVM.setJenkinsJVM(true);
         try {
-            assertThrows(IllegalStateException.class, () -> JenkinsJVM.checkNotJenkinsJVM());
+            assertThrows(IllegalStateException.class, JenkinsJVM::checkNotJenkinsJVM);
         } finally {
             JenkinsJVM.setJenkinsJVM(false);
         }

core/src/test/java/jenkins/util/VirtualFileTest.java

@@ -100,7 +100,7 @@ public class VirtualFileTest {
         VirtualFile hack = root.child("hack");
         assertFalse(hack.isFile());
         assertFalse(hack.exists());
-        assertThrows(FileNotFoundException.class, () -> hack.open());
+        assertThrows(FileNotFoundException.class, hack::open);
     }
 
     @Issue("JENKINS-26810")