diff --git a/core/src/main/java/hudson/ClassicPluginStrategy.java b/core/src/main/java/hudson/ClassicPluginStrategy.java
index 907b2ee9c3..026594a02b 100644
--- a/core/src/main/java/hudson/ClassicPluginStrategy.java
+++ b/core/src/main/java/hudson/ClassicPluginStrategy.java
@@ -535,7 +535,7 @@ public class ClassicPluginStrategy implements PluginStrategy {
 
         final long dirTime = archive.lastModified();
         // this ZipOutputStream is reused and not created for each directory
-        try (ZipOutputStream wrappedZOut = new ZipOutputStream(new NullOutputStream()) {
+        try (ZipOutputStream wrappedZOut = new ZipOutputStream(NullOutputStream.NULL_OUTPUT_STREAM) {
             @Override
             public void putNextEntry(ZipEntry ze) throws IOException {
                 ze.setTime(dirTime+1999);   // roundup
diff --git a/core/src/main/java/hudson/TcpSlaveAgentListener.java b/core/src/main/java/hudson/TcpSlaveAgentListener.java
index d86b534fb1..b524f4b720 100644
--- a/core/src/main/java/hudson/TcpSlaveAgentListener.java
+++ b/core/src/main/java/hudson/TcpSlaveAgentListener.java
@@ -345,7 +345,7 @@ public final class TcpSlaveAgentListener extends Thread {
                 }
 
                 InputStream i = s.getInputStream();
-                IOUtils.copy(i, new NullOutputStream());
+                IOUtils.copy(i, NullOutputStream.NULL_OUTPUT_STREAM);
                 s.shutdownInput();
             } finally {
                 s.close();
diff --git a/core/src/main/java/hudson/model/UpdateCenter.java b/core/src/main/java/hudson/model/UpdateCenter.java
index e8f0dbc6cf..d217f1decd 100644
--- a/core/src/main/java/hudson/model/UpdateCenter.java
+++ b/core/src/main/java/hudson/model/UpdateCenter.java
@@ -1408,7 +1408,7 @@ public class UpdateCenter extends AbstractModelObject implements Saveable, OnMas
                     }
                 } else {
                     try (InputStream is = connection.getInputStream()) {
-                        IOUtils.copy(is, new NullOutputStream());
+                        IOUtils.copy(is, NullOutputStream.NULL_OUTPUT_STREAM);
                     }
                 }
             } catch (SSLHandshakeException e) {
diff --git a/core/src/main/java/jenkins/util/JSONSignatureValidator.java b/core/src/main/java/jenkins/util/JSONSignatureValidator.java
index 5c8bc4d0ea..7e9135b47b 100644
--- a/core/src/main/java/jenkins/util/JSONSignatureValidator.java
+++ b/core/src/main/java/jenkins/util/JSONSignatureValidator.java
@@ -156,7 +156,7 @@ public class JSONSignatureValidator {
      */
     private FormValidation checkSpecificSignature(JSONObject json, JSONObject signatureJson, MessageDigest digest, String digestEntry, Signature signature, String signatureEntry, String digestName) throws IOException {
         // this is for computing a digest to check sanity
-        DigestOutputStream dos = new DigestOutputStream(new NullOutputStream(), digest);
+        DigestOutputStream dos = new DigestOutputStream(NullOutputStream.NULL_OUTPUT_STREAM, digest);
         SignatureOutputStream sos = new SignatureOutputStream(signature);
 
         String providedDigest = signatureJson.optString(digestEntry, null);
diff --git a/core/src/test/java/hudson/FilePathTest.java b/core/src/test/java/hudson/FilePathTest.java
index 26b93b8048..e4d63df2c3 100644
--- a/core/src/test/java/hudson/FilePathTest.java
+++ b/core/src/test/java/hudson/FilePathTest.java
@@ -242,8 +242,8 @@ public class FilePathTest {
     @Test public void archiveBug() throws Exception {
             FilePath d = new FilePath(channels.french, temp.getRoot().getPath());
             d.child("test").touch(0);
-            d.zip(new NullOutputStream());
-            d.zip(new NullOutputStream(),"**/*");
+            d.zip(NullOutputStream.NULL_OUTPUT_STREAM);
+            d.zip(NullOutputStream.NULL_OUTPUT_STREAM,"**/*");
     }
 
     @Test public void normalization() throws Exception {
diff --git a/core/src/test/java/hudson/slaves/ComputerLauncherTest.java b/core/src/test/java/hudson/slaves/ComputerLauncherTest.java
index 4aa8cb2036..780946df0f 100644
--- a/core/src/test/java/hudson/slaves/ComputerLauncherTest.java
+++ b/core/src/test/java/hudson/slaves/ComputerLauncherTest.java
@@ -52,11 +52,11 @@ public class ComputerLauncherTest {
     }
 
     @Test public void jdk5() {
-        assertThrows(IOException.class, () -> ComputerLauncher.checkJavaVersion(new PrintStream(new NullOutputStream()), "-", new BufferedReader(new StringReader("java version \"1.5.0_22\"\nJava(TM) 2 Runtime Environment, Standard Edition (build 1.5.0_22-b03)\nJava HotSpot(TM) Server VM (build 1.5.0_22-b03, mixed mode)\n"))));
+        assertThrows(IOException.class, () -> ComputerLauncher.checkJavaVersion(new PrintStream(NullOutputStream.NULL_OUTPUT_STREAM), "-", new BufferedReader(new StringReader("java version \"1.5.0_22\"\nJava(TM) 2 Runtime Environment, Standard Edition (build 1.5.0_22-b03)\nJava HotSpot(TM) Server VM (build 1.5.0_22-b03, mixed mode)\n"))));
     }
 
     @Test public void j2sdk4() {
-        assertThrows(IOException.class, () -> ComputerLauncher.checkJavaVersion(new PrintStream(new NullOutputStream()), "-", new BufferedReader(new StringReader("java version \"1.4.2_19\"\nJava(TM) 2 Runtime Environment, Standard Edition (build 1.4.2_19-b04)\nJava HotSpot(TM) Client VM (build 1.4.2_19-b04, mixed mode)\n"))));
+        assertThrows(IOException.class, () -> ComputerLauncher.checkJavaVersion(new PrintStream(NullOutputStream.NULL_OUTPUT_STREAM), "-", new BufferedReader(new StringReader("java version \"1.4.2_19\"\nJava(TM) 2 Runtime Environment, Standard Edition (build 1.4.2_19-b04)\nJava HotSpot(TM) Client VM (build 1.4.2_19-b04, mixed mode)\n"))));
     }
 
     @Test public void jdk8() throws IOException {
diff --git a/core/src/test/java/jenkins/RemotingJarSignatureTest.java b/core/src/test/java/jenkins/RemotingJarSignatureTest.java
index 60c878b20f..7bf5ac7264 100644
--- a/core/src/test/java/jenkins/RemotingJarSignatureTest.java
+++ b/core/src/test/java/jenkins/RemotingJarSignatureTest.java
@@ -42,7 +42,7 @@ public class RemotingJarSignatureTest {
             if (name.startsWith("META-INF/") && name.endsWith(".DSA")) continue;
 
             // make sure bits are signed
-            IOUtils.copy(myJar.getInputStream(entry), new NullOutputStream());
+            IOUtils.copy(myJar.getInputStream(entry), NullOutputStream.NULL_OUTPUT_STREAM);
             if (entry.getCodeSigners()==null) {
                 fail("No signature for " + name);
             }