diff --git a/pom.xml b/pom.xml
index 959ff2959e..cf085263fb 100644
--- a/pom.xml
+++ b/pom.xml
@@ -33,8 +33,8 @@
 
   <properties>
     <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
-    <spotbugs-maven-plugin.version>4.4.2.2</spotbugs-maven-plugin.version>
-    <spotbugs.version>4.4.2</spotbugs.version>
+    <spotbugs-maven-plugin.version>4.5.0.0</spotbugs-maven-plugin.version>
+    <spotbugs.version>4.5.0</spotbugs.version>
     <spotbugs-maven-plugin.failOnError>true</spotbugs-maven-plugin.failOnError>
     <hamcrest.version>2.2</hamcrest.version>
     <okhttp3.version>4.9.2</okhttp3.version>
diff --git a/src/main/java/org/kohsuke/github/GitHubClient.java b/src/main/java/org/kohsuke/github/GitHubClient.java
index 4e20e55c03..fefd6cb0c3 100644
--- a/src/main/java/org/kohsuke/github/GitHubClient.java
+++ b/src/main/java/org/kohsuke/github/GitHubClient.java
@@ -578,20 +578,12 @@ private void detectInvalidCached404Response(GitHubConnectorResponse connectorRes
     private void noteRateLimit(@Nonnull RateLimitTarget rateLimitTarget,
             @Nonnull GitHubConnectorResponse connectorResponse) {
         try {
-            String limitString = Objects.requireNonNull(connectorResponse.header("X-RateLimit-Limit"),
-                    "Missing X-RateLimit-Limit");
-            String remainingString = Objects.requireNonNull(connectorResponse.header("X-RateLimit-Remaining"),
-                    "Missing X-RateLimit-Remaining");
-            String resetString = Objects.requireNonNull(connectorResponse.header("X-RateLimit-Reset"),
-                    "Missing X-RateLimit-Reset");
-            int limit, remaining;
-            long reset;
-            limit = Integer.parseInt(limitString);
-            remaining = Integer.parseInt(remainingString);
-            reset = Long.parseLong(resetString);
+            int limit = connectorResponse.parseInt("X-RateLimit-Limit");
+            int remaining = connectorResponse.parseInt("X-RateLimit-Remaining");
+            int reset = connectorResponse.parseInt("X-RateLimit-Reset");
             GHRateLimit.Record observed = new GHRateLimit.Record(limit, remaining, reset, connectorResponse);
             updateRateLimit(GHRateLimit.fromRecord(observed, rateLimitTarget));
-        } catch (NumberFormatException | NullPointerException e) {
+        } catch (NumberFormatException e) {
             LOGGER.log(FINEST, "Missing or malformed X-RateLimit header: ", e);
         }
     }
diff --git a/src/main/java/org/kohsuke/github/GitHubResponse.java b/src/main/java/org/kohsuke/github/GitHubResponse.java
index ffb6608243..292b3b4524 100644
--- a/src/main/java/org/kohsuke/github/GitHubResponse.java
+++ b/src/main/java/org/kohsuke/github/GitHubResponse.java
@@ -122,10 +122,11 @@ static <T> T parseBody(GitHubConnectorResponse connectorResponse, T instance) th
     /**
      * Gets the body of the response as a {@link String}.
      *
+     * @param connectorResponse
+     *            the response to read
      * @return the body of the response as a {@link String}.
      * @throws IOException
      *             if an I/O Exception occurs.
-     * @param connectorResponse
      */
     @Nonnull
     static String getBodyAsString(GitHubConnectorResponse connectorResponse) throws IOException {
@@ -138,15 +139,16 @@ static String getBodyAsString(GitHubConnectorResponse connectorResponse) throws
     /**
      * Gets the body of the response as a {@link String}.
      *
+     * @param connectorResponse
+     *            the response to read
      * @return the body of the response as a {@link String}.
      * @throws IOException
      *             if an I/O Exception occurs.
-     * @param connectorResponse
      */
     static String getBodyAsStringOrNull(GitHubConnectorResponse connectorResponse) {
         try {
             return getBodyAsString(connectorResponse);
-        } catch (NullPointerException | IOException e) {
+        } catch (IOException e) {
         }
         return null;
     }
diff --git a/src/main/java/org/kohsuke/github/connector/GitHubConnectorResponse.java b/src/main/java/org/kohsuke/github/connector/GitHubConnectorResponse.java
index 3700236074..c73b2e0c8d 100644
--- a/src/main/java/org/kohsuke/github/connector/GitHubConnectorResponse.java
+++ b/src/main/java/org/kohsuke/github/connector/GitHubConnectorResponse.java
@@ -86,8 +86,9 @@ public String header(String name) {
      *
      * @return the response body
      * @throws IOException
-     *             if an I/O Exception occurs.
+     *             if response stream is null or an I/O Exception occurs.
      */
+    @Nonnull
     public abstract InputStream bodyStream() throws IOException;
 
     /**
@@ -121,7 +122,7 @@ public Map<String, List<String>> allHeaders() {
     }
 
     /**
-     * Handles the "Content-Encoding" header.
+     * Handles wrapping the body stream if indicated by the "Content-Encoding" header.
      *
      * @param stream
      *            the stream to possibly wrap
@@ -139,6 +140,24 @@ protected InputStream wrapStream(InputStream stream) throws IOException {
         throw new UnsupportedOperationException("Unexpected Content-Encoding: " + encoding);
     }
 
+    /**
+     * Parse a header value as a signed decimal integer.
+     *
+     * @param name
+     *            the header field to parse
+     * @return integer value of the header field
+     * @throws NumberFormatException
+     *             if the header is missing or does not contain a parsable integer.
+     */
+    public final int parseInt(String name) throws NumberFormatException {
+        try {
+            String headerValue = header(name);
+            return Integer.parseInt(headerValue);
+        } catch (NumberFormatException e) {
+            throw new NumberFormatException(name + ": " + e.getMessage());
+        }
+    }
+
     public abstract static class ByteArrayResponse extends GitHubConnectorResponse {
 
         private boolean inputStreamRead = false;
@@ -155,6 +174,7 @@ protected ByteArrayResponse(@Nonnull GitHubConnectorRequest request,
          * {@inheritDoc}
          */
         @Override
+        @Nonnull
         public InputStream bodyStream() throws IOException {
             if (isClosed) {
                 throw new IOException("Response is closed");
@@ -171,7 +191,11 @@ public InputStream bodyStream() throws IOException {
                 }
             }
 
-            return inputBytes == null ? null : new ByteArrayInputStream(inputBytes);
+            if (inputBytes == null) {
+                throw new IOException("Response body missing, stream null");
+            }
+
+            return new ByteArrayInputStream(inputBytes);
         }
 
         /**
diff --git a/src/main/java/org/kohsuke/github/internal/EnumUtils.java b/src/main/java/org/kohsuke/github/internal/EnumUtils.java
index 7d247ad807..9c4253b3cc 100644
--- a/src/main/java/org/kohsuke/github/internal/EnumUtils.java
+++ b/src/main/java/org/kohsuke/github/internal/EnumUtils.java
@@ -49,12 +49,15 @@ public static <E extends Enum<E>> E getNullableEnumOrDefault(Class<E> enumClass,
      */
     public static <E extends Enum<E>> E getEnumOrDefault(Class<E> enumClass, String value, E defaultEnum) {
         try {
-            return Enum.valueOf(enumClass, value.toUpperCase(Locale.ROOT));
-        } catch (NullPointerException | IllegalArgumentException e) {
-            LOGGER.warning("Unknown value " + value + " for enum class " + enumClass.getName() + ", defaulting to "
-                    + defaultEnum.name());
-            return defaultEnum;
+            if (value != null) {
+                return Enum.valueOf(enumClass, value.toUpperCase(Locale.ROOT));
+            }
+        } catch (IllegalArgumentException e) {
         }
+
+        LOGGER.warning("Unknown value " + value + " for enum class " + enumClass.getName() + ", defaulting to "
+                + defaultEnum.name());
+        return defaultEnum;
     }
 
     private EnumUtils() {