diff --git a/README.md b/README.md
index 6a11f0fc4..02941c2b6 100644
--- a/README.md
+++ b/README.md
@@ -97,8 +97,8 @@ Users can subscribe to HTTP requests and responses via the `RequestHook` and `Re
     EasyPostClient client = new EasyPostClient(System.getenv("EASYPOST_API_KEY"));
 
     // For request hook custom function, make sure you have RequestHookResponses in the parameter
-    public static Object requestHookFunction(RequestHookResponses datas) {
-        // Pass your code here, the information about the request/response is available within the datas parameter.
+    public static Object requestHookFunction(RequestHookResponses data) {
+        // Pass your code here, the information about the request/response is available within the data parameter.
         return true;
     }
 
@@ -106,13 +106,13 @@ Users can subscribe to HTTP requests and responses via the `RequestHook` and `Re
     client.unsubscribeToRequestHook(requestHookFunction); // unsubscribe from request hook
 
     // For response hook custom function, make sure you have ResponseHookResponses in the parameter
-    public static Object responseHookFunction(ResponseHookResponses datas) {
-        // Pass your code here, the information about the request/response is available within the datas parameter.
+    public static Object responseHookFunction(ResponseHookResponses data) {
+        // Pass your code here, the information about the request/response is available within the data parameter.
         return true;
     }
 
-    client.subscribeToRequestHook(responseHookFunction); // subscribe to response hook by passing your custom function
-    client.unsubscribeToRequestHook(responseHookFunction); // unsubscribe from response hook
+    client.subscribeToResponseHook(responseHookFunction); // subscribe to response hook by passing your custom function
+    client.unsubscribeToResponseHook(responseHookFunction); // unsubscribe from response hook
 ```
 
 ## Documentation
diff --git a/src/main/java/com/easypost/exception/APIException.java b/src/main/java/com/easypost/exception/APIException.java
index fb8256b0b..5bed1bed8 100644
--- a/src/main/java/com/easypost/exception/APIException.java
+++ b/src/main/java/com/easypost/exception/APIException.java
@@ -91,6 +91,7 @@ public String getCode() {
      *
      * @return message the message of the error object
      */
+    @Override
     public String getMessage() {
         return message;
     }
diff --git a/src/main/java/com/easypost/hooks/RequestHook.java b/src/main/java/com/easypost/hooks/RequestHook.java
index 2df3dad42..1b5cafedf 100644
--- a/src/main/java/com/easypost/hooks/RequestHook.java
+++ b/src/main/java/com/easypost/hooks/RequestHook.java
@@ -29,6 +29,7 @@ public void removeEventHandler(Function<RequestHookResponses, Object> handler) {
      */
     public void executeEventHandler(RequestHookResponses datas) {
         for (Function<RequestHookResponses, Object> eventHandler : eventHandlers) {
+            @SuppressWarnings("unused")
             Object result = eventHandler.apply(datas);
         }
     }
diff --git a/src/main/java/com/easypost/hooks/ResponseHook.java b/src/main/java/com/easypost/hooks/ResponseHook.java
index 965b9c989..47d0452c6 100644
--- a/src/main/java/com/easypost/hooks/ResponseHook.java
+++ b/src/main/java/com/easypost/hooks/ResponseHook.java
@@ -29,6 +29,7 @@ public void removeEventHandler(Function<ResponseHookResponses, Object> handler)
      */
     public void executeEventHandler(ResponseHookResponses datas) {
         for (Function<ResponseHookResponses, Object> eventHandler : eventHandlers) {
+            @SuppressWarnings("unused")
             Object result = eventHandler.apply(datas);
         }
     }
diff --git a/src/main/java/com/easypost/http/Requestor.java b/src/main/java/com/easypost/http/Requestor.java
index 980eba3ca..3b9444d84 100644
--- a/src/main/java/com/easypost/http/Requestor.java
+++ b/src/main/java/com/easypost/http/Requestor.java
@@ -50,6 +50,7 @@
 import java.net.URL;
 import java.net.URLEncoder;
 import java.net.URLStreamHandler;
+import java.nio.charset.Charset;
 import java.time.Instant;
 import java.util.HashMap;
 import java.util.List;
@@ -78,7 +79,7 @@ private static String urlEncodePair(final String key, final String value) throws
      *
      * @param apiKey API of this HTTP request.
      * @return HTTP header
-     * @throws MissingParameterError
+     * @throws MissingParameterError When the request fails.
      */
     private static Map<String, String> generateHeaders(String apiKey) throws MissingParameterError {
         Map<String, String> headers = new HashMap<String, String>();
@@ -159,7 +160,7 @@ private static javax.net.ssl.HttpsURLConnection createEasyPostConnection(final S
      * @param conn EasyPost HttpsURLConnection
      * @param body Input body
      * @return HttpsURLConnection
-     * @throws IOException
+     * @throws IOException When the request fails.
      */
     private static javax.net.ssl.HttpsURLConnection writeBody(final javax.net.ssl.HttpsURLConnection conn,
             final JsonObject body) throws IOException {
@@ -276,7 +277,7 @@ private static JsonObject createBody(final Map<String, Object> params) {
      *
      * @param params Map of parameter for the HTTP request body.
      * @return Query string of the Map object.
-     * @throws UnsupportedEncodingException
+     * @throws UnsupportedEncodingException When the request fails.
      */
     private static String createQuery(final Map<String, Object> params) throws UnsupportedEncodingException {
         Map<String, String> flatParams = flattenParams(params);
@@ -329,7 +330,7 @@ private static Map<String, String> flattenParams(final Map<String, Object> param
      *
      * @param responseStream The InputStream from the response body.
      * @return InputStream in string value.
-     * @throws IOException
+     * @throws IOException When the request fails.
      */
     private static String getResponseBody(final InputStream responseStream) throws IOException {
         if (responseStream.available() == 0) {
@@ -583,8 +584,7 @@ private static <T> T httpRequest(final RequestMethod method, final String url, f
         }
         Instant requestTimestamp = Instant.now();
         UUID requestUuid = UUID.randomUUID();
-        Map<String, String> headers = new HashMap<String, String>();
-        headers = generateHeaders(client.getApiKey());
+        Map<String, String> headers = generateHeaders(client.getApiKey());
 
         RequestHookResponses requestResponse = new RequestHookResponses(headers, method.toString(), url, body,
                 requestTimestamp.toString(), requestUuid.toString());
@@ -744,7 +744,8 @@ private static EasyPostResponse makeAppEngineRequest(final RequestMethod method,
 
             if ((method == RequestMethod.POST || method == RequestMethod.PUT) && body != null) {
                 String bodyString = body.toString();
-                requestClass.getDeclaredMethod("setPayload", byte[].class).invoke(request, bodyString.getBytes());
+                requestClass.getDeclaredMethod("setPayload", byte[].class)
+                    .invoke(request, bodyString.getBytes(Charset.defaultCharset()));
             }
 
             for (Map.Entry<String, String> header : generateHeaders(client.getApiKey()).entrySet()) {
diff --git a/src/main/java/com/easypost/model/CarrierMetadata.java b/src/main/java/com/easypost/model/CarrierMetadata.java
index 073393236..6b9b7a025 100644
--- a/src/main/java/com/easypost/model/CarrierMetadata.java
+++ b/src/main/java/com/easypost/model/CarrierMetadata.java
@@ -9,7 +9,7 @@ public class CarrierMetadata extends EasyPostResource {
     private List<Carrier> carriers;
     
     @Getter
-    public class Carrier {
+    public static class Carrier {
         private String name;
         private String humanReadable;
         private List<PredefinedPackage> predefinedPackages;
@@ -19,7 +19,7 @@ public class Carrier {
     }
 
     @Getter
-    public class PredefinedPackage {
+    public static class PredefinedPackage {
         private String carrier;
         private String description;
         private List<String> dimensions;
@@ -29,7 +29,7 @@ public class PredefinedPackage {
     }
 
     @Getter
-    public class ServiceLevels {
+    public static class ServiceLevels {
         private String carrier;
         private String description;
         private List<String> dimensions;
@@ -39,7 +39,7 @@ public class ServiceLevels {
     }
 
     @Getter
-    public class ShipmentOption {
+    public static class ShipmentOption {
         private String carrier;
         private boolean deprecated;
         private String description;
@@ -49,7 +49,7 @@ public class ShipmentOption {
     }
 
     @Getter
-    public class SupportedFeatures {
+    public static class SupportedFeatures {
         private String carrier;
         private String description;
         private String name;
diff --git a/src/main/java/com/easypost/model/Error.java b/src/main/java/com/easypost/model/Error.java
index 8f1ee3efc..c6b18a143 100644
--- a/src/main/java/com/easypost/model/Error.java
+++ b/src/main/java/com/easypost/model/Error.java
@@ -4,6 +4,7 @@
 import lombok.Getter;
 
 @Getter
+@SuppressWarnings("JavaLangClash")
 public final class Error {
     private String message;
     private String code;
diff --git a/src/main/java/com/easypost/service/AddressService.java b/src/main/java/com/easypost/service/AddressService.java
index bc0e6b18a..83e8eb388 100644
--- a/src/main/java/com/easypost/service/AddressService.java
+++ b/src/main/java/com/easypost/service/AddressService.java
@@ -97,7 +97,7 @@ public AddressCollection getNextPage(AddressCollection collection) throws EndOfP
      */
     public AddressCollection getNextPage(AddressCollection collection, Integer pageSize) throws EndOfPaginationError {
         return collection.getNextPage(new Function<Map<String, Object>, AddressCollection>() {
-            @SneakyThrows
+            @Override @SneakyThrows
             public AddressCollection apply(Map<String, Object> parameters) {
                 return all(parameters);
             }
diff --git a/src/main/java/com/easypost/service/BetaCarrierMetadataService.java b/src/main/java/com/easypost/service/BetaCarrierMetadataService.java
index 98b087088..d5c30be16 100644
--- a/src/main/java/com/easypost/service/BetaCarrierMetadataService.java
+++ b/src/main/java/com/easypost/service/BetaCarrierMetadataService.java
@@ -24,7 +24,7 @@ public class BetaCarrierMetadataService {
      * Retrieves all carrier metadata.
      *
      * @return CarrierMetadata object
-     * @throws EasyPostException
+     * @throws EasyPostException When the request fails.
      * @deprecated Use carrierMetadata.retrieve instead
      */
     public CarrierMetadata retrieveCarrierMetadata() throws EasyPostException {
@@ -36,7 +36,7 @@ public CarrierMetadata retrieveCarrierMetadata() throws EasyPostException {
      *
      * @param carriers The list of carriers in string.
      * @return CarrierMetadata object
-     * @throws EasyPostException
+     * @throws EasyPostException When the request fails.
      * @deprecated Use carrierMetadata.retrieve instead
      */
     public CarrierMetadata retrieveCarrierMetadata(List<String> carriers) throws EasyPostException {
@@ -49,7 +49,7 @@ public CarrierMetadata retrieveCarrierMetadata(List<String> carriers) throws Eas
      * @param carriers The list of carriers in string.
      * @param types    The list of types in string.
      * @return CarrierMetadata object
-     * @throws EasyPostException
+     * @throws EasyPostException When the request fails.
      * @deprecated Use carrierMetadata.retrieve instead
      */
     public CarrierMetadata retrieveCarrierMetadata(List<String> carriers, List<String> types) throws EasyPostException {
diff --git a/src/main/java/com/easypost/service/BetaReferralCustomerService.java b/src/main/java/com/easypost/service/BetaReferralCustomerService.java
index aa2196a2c..474312c40 100644
--- a/src/main/java/com/easypost/service/BetaReferralCustomerService.java
+++ b/src/main/java/com/easypost/service/BetaReferralCustomerService.java
@@ -27,7 +27,7 @@ public class BetaReferralCustomerService {
      * @param stripeCustomerId       ID of the Stripe account.
      * @param paymentMethodReference Reference of Stripe payment method.
      * @return PaymentMethodObject object.
-     * @throws EasyPostException
+     * @throws EasyPostException     When the request fails.
      */
     public PaymentMethodObject addPaymentMethod(String stripeCustomerId, String paymentMethodReference)
             throws EasyPostException {
@@ -41,7 +41,7 @@ public PaymentMethodObject addPaymentMethod(String stripeCustomerId, String paym
      * @param paymentMethodReference Reference of Stripe payment method.
      * @param primaryOrSecondary     Primary or secondary of this payment method.
      * @return PaymentMethodObject object.
-     * @throws EasyPostException
+     * @throws EasyPostException     When the request fails.
      */
     public PaymentMethodObject addPaymentMethod(String stripeCustomerId, String paymentMethodReference,
             PaymentMethod.Priority primaryOrSecondary) throws EasyPostException {
@@ -64,7 +64,7 @@ public PaymentMethodObject addPaymentMethod(String stripeCustomerId, String paym
      *
      * @param refundAmount Amount to be refunded by cents.
      * @return BetaPaymentRefund object.
-     * @throws EasyPostException
+     * @throws EasyPostException When the request fails.
      */
     public BetaPaymentRefund refundByAmount(int refundAmount) throws EasyPostException {
         HashMap<String, Object> params = new HashMap<>();
@@ -81,7 +81,7 @@ public BetaPaymentRefund refundByAmount(int refundAmount) throws EasyPostExcepti
      *
      * @param paymentLogId ID of the payment log.
      * @return BetaPaymentRefund object.
-     * @throws EasyPostException
+     * @throws EasyPostException When the request fails.
      */
     public BetaPaymentRefund refundByPaymentLog(String paymentLogId) throws EasyPostException {
         HashMap<String, Object> params = new HashMap<>();
diff --git a/src/main/java/com/easypost/service/CarrierMetadataService.java b/src/main/java/com/easypost/service/CarrierMetadataService.java
index b6bf04ba0..df3466d7b 100644
--- a/src/main/java/com/easypost/service/CarrierMetadataService.java
+++ b/src/main/java/com/easypost/service/CarrierMetadataService.java
@@ -24,7 +24,7 @@ public class CarrierMetadataService {
      * Retrieves all carrier metadata.
      *
      * @return CarrierMetadata object
-     * @throws EasyPostException
+     * @throws EasyPostException When the request fails.
      */
     public CarrierMetadata retrieve() throws EasyPostException {
         return retrieve(null);
@@ -35,7 +35,7 @@ public CarrierMetadata retrieve() throws EasyPostException {
      *
      * @param carriers The list of carriers in string.
      * @return CarrierMetadata object
-     * @throws EasyPostException
+     * @throws EasyPostException When the request fails.
      */
     public CarrierMetadata retrieve(List<String> carriers) throws EasyPostException {
         return retrieve(carriers, null);
@@ -47,7 +47,7 @@ public CarrierMetadata retrieve(List<String> carriers) throws EasyPostException
      * @param carriers The list of carriers in string.
      * @param types    The list of types in string.
      * @return CarrierMetadata object
-     * @throws EasyPostException
+     * @throws EasyPostException When the request fails.
      */
     public CarrierMetadata retrieve(List<String> carriers, List<String> types) throws EasyPostException {
         HashMap<String, Object> params = new HashMap<>();
diff --git a/src/main/java/com/easypost/service/EasyPostClient.java b/src/main/java/com/easypost/service/EasyPostClient.java
index 4447a0ebe..9a4f78acf 100644
--- a/src/main/java/com/easypost/service/EasyPostClient.java
+++ b/src/main/java/com/easypost/service/EasyPostClient.java
@@ -54,7 +54,7 @@ public class EasyPostClient {
      * EasyPostClient constructor.
      *
      * @param apiKey API key for API calls.
-     * @throws MissingParameterError
+     * @throws MissingParameterError When the request fails.
      */
     public EasyPostClient(String apiKey) throws MissingParameterError {
         this(apiKey, Constants.Http.DEFAULT_CONNECT_TIMEOUT_MILLISECONDS);
@@ -65,7 +65,7 @@ public EasyPostClient(String apiKey) throws MissingParameterError {
      *
      * @param apiKey  API key for API calls.
      * @param apiBase API base for API calls.
-     * @throws MissingParameterError
+     * @throws MissingParameterError When the request fails.
      */
     public EasyPostClient(String apiKey, String apiBase) throws MissingParameterError {
         this(apiKey, Constants.Http.DEFAULT_CONNECT_TIMEOUT_MILLISECONDS,
@@ -77,7 +77,7 @@ public EasyPostClient(String apiKey, String apiBase) throws MissingParameterErro
      *
      * @param apiKey                     API key for API calls.
      * @param connectTimeoutMilliseconds Timeout for connection.
-     * @throws MissingParameterError
+     * @throws MissingParameterError     When the request fails.
      */
     public EasyPostClient(String apiKey, int connectTimeoutMilliseconds) throws MissingParameterError {
         this(apiKey, connectTimeoutMilliseconds, Constants.Http.API_BASE);
@@ -89,7 +89,7 @@ public EasyPostClient(String apiKey, int connectTimeoutMilliseconds) throws Miss
      * @param apiKey                     API key for API calls.
      * @param connectTimeoutMilliseconds Timeout for connection.
      * @param apiBase                    API base for API calls.
-     * @throws MissingParameterError
+     * @throws MissingParameterError     When the request fails.
      */
     public EasyPostClient(String apiKey, int connectTimeoutMilliseconds, String apiBase) throws MissingParameterError {
         this(apiKey, connectTimeoutMilliseconds, Constants.Http.DEFAULT_READ_TIMEOUT_MILLISECONDS, apiBase);
@@ -101,7 +101,7 @@ public EasyPostClient(String apiKey, int connectTimeoutMilliseconds, String apiB
      * @param apiKey                     API key for API calls.
      * @param connectTimeoutMilliseconds Timeout for connection.
      * @param readTimeoutMilliseconds    Timeout for read.
-     * @throws MissingParameterError
+     * @throws MissingParameterError     When the request fails.
      */
     public EasyPostClient(String apiKey, int connectTimeoutMilliseconds, int readTimeoutMilliseconds)
             throws MissingParameterError {
@@ -115,7 +115,7 @@ public EasyPostClient(String apiKey, int connectTimeoutMilliseconds, int readTim
      * @param connectTimeoutMilliseconds Timeout for connection.
      * @param readTimeoutMilliseconds    Timeout for read.
      * @param apiBase                    API base for API calls.
-     * @throws MissingParameterError
+     * @throws MissingParameterError     When the request fails.
      */
     public EasyPostClient(String apiKey, int connectTimeoutMilliseconds, int readTimeoutMilliseconds, String apiBase)
             throws MissingParameterError {
@@ -159,7 +159,7 @@ public EasyPostClient(String apiKey, int connectTimeoutMilliseconds, int readTim
 
     /**
      * Subscribes to a request hook from the given function.
-     * @param function
+     * @param function The function to be subscribed to the request hook
      */
     public void subscribeToRequestHook(Function<RequestHookResponses, Object> function) {
         this.requestHooks.addEventHandler(function);
@@ -167,7 +167,7 @@ public void subscribeToRequestHook(Function<RequestHookResponses, Object> functi
 
     /**
      * Unsubscribes to a request hook from the given function.
-     * @param function
+     * @param function The function to be unsubscribed from the request hook
      */
     public void unsubscribeFromRequestHook(Function<RequestHookResponses, Object> function) {
         this.requestHooks.removeEventHandler(function);
@@ -175,7 +175,7 @@ public void unsubscribeFromRequestHook(Function<RequestHookResponses, Object> fu
 
     /**
      * Subscribes to a response hook from the given function.
-     * @param function
+     * @param function The function to be subscribed to the response hook
      */
     public void subscribeToResponseHook(Function<ResponseHookResponses, Object> function) {
         this.responseHooks.addEventHandler(function);
@@ -183,7 +183,7 @@ public void subscribeToResponseHook(Function<ResponseHookResponses, Object> func
 
     /**
      * Unubscribes to a response hook from the given function.
-     * @param function
+     * @param function The function to be unsubscribed from the response hook
      */
     public void unsubscribeFromResponseHook(Function<ResponseHookResponses, Object> function) {
         this.responseHooks.removeEventHandler(function);
diff --git a/src/main/java/com/easypost/service/EventService.java b/src/main/java/com/easypost/service/EventService.java
index 7c6545504..3981f996b 100644
--- a/src/main/java/com/easypost/service/EventService.java
+++ b/src/main/java/com/easypost/service/EventService.java
@@ -73,7 +73,7 @@ public EventCollection getNextPage(EventCollection collection) throws EndOfPagin
      */
     public EventCollection getNextPage(EventCollection collection, Integer pageSize) throws EndOfPaginationError {
         return collection.getNextPage(new Function<Map<String, Object>, EventCollection>() {
-            @SneakyThrows
+            @Override @SneakyThrows
             public EventCollection apply(Map<String, Object> parameters) {
                 return all(parameters);
             }
diff --git a/src/main/java/com/easypost/service/InsuranceService.java b/src/main/java/com/easypost/service/InsuranceService.java
index 510a027e8..375980752 100644
--- a/src/main/java/com/easypost/service/InsuranceService.java
+++ b/src/main/java/com/easypost/service/InsuranceService.java
@@ -88,7 +88,7 @@ public InsuranceCollection getNextPage(InsuranceCollection collection) throws En
     public InsuranceCollection getNextPage(
             InsuranceCollection collection, Integer pageSize) throws EndOfPaginationError {
         return collection.getNextPage(new Function<Map<String, Object>, InsuranceCollection>() {
-            @SneakyThrows
+            @Override @SneakyThrows
             public InsuranceCollection apply(Map<String, Object> parameters) {
                 return all(parameters);
             }
diff --git a/src/main/java/com/easypost/service/PickupService.java b/src/main/java/com/easypost/service/PickupService.java
index e8540287c..b0feeb89d 100644
--- a/src/main/java/com/easypost/service/PickupService.java
+++ b/src/main/java/com/easypost/service/PickupService.java
@@ -59,7 +59,7 @@ public PickupCollection getNextPage(PickupCollection collection) throws EndOfPag
      */
     public PickupCollection getNextPage(PickupCollection collection, Integer pageSize) throws EndOfPaginationError {
         return collection.getNextPage(new Function<Map<String, Object>, PickupCollection>() {
-            @SneakyThrows
+            @Override @SneakyThrows
             public PickupCollection apply(Map<String, Object> parameters) {
                 return all(parameters);
             }
diff --git a/src/main/java/com/easypost/service/ReferralCustomerService.java b/src/main/java/com/easypost/service/ReferralCustomerService.java
index 3b4977923..92c0b4309 100644
--- a/src/main/java/com/easypost/service/ReferralCustomerService.java
+++ b/src/main/java/com/easypost/service/ReferralCustomerService.java
@@ -20,6 +20,7 @@
 import java.io.InputStreamReader;
 import java.net.HttpURLConnection;
 import java.net.URL;
+import java.nio.charset.StandardCharsets;
 import java.util.HashMap;
 import java.util.Map;
 import java.util.function.Function;
@@ -110,7 +111,7 @@ public ReferralCustomerCollection getNextPage(ReferralCustomerCollection collect
     public ReferralCustomerCollection getNextPage(
             ReferralCustomerCollection collection, Integer pageSize) throws EndOfPaginationError {
         return collection.getNextPage(new Function<Map<String, Object>, ReferralCustomerCollection>() {
-            @SneakyThrows
+            @Override @SneakyThrows
             public ReferralCustomerCollection apply(Map<String, Object> parameters) {
                 return all(parameters);
             }
@@ -220,8 +221,8 @@ private static String createStripeToken(final String number, final int expiratio
 
         StringBuilder response;
 
-        try (BufferedReader br = new BufferedReader(new InputStreamReader(conn.getInputStream()))) {
-
+        try (BufferedReader br = new BufferedReader(
+                new InputStreamReader(conn.getInputStream(), StandardCharsets.UTF_8))) {
             String line;
             response = new StringBuilder();
 
diff --git a/src/main/java/com/easypost/service/RefundService.java b/src/main/java/com/easypost/service/RefundService.java
index cf686431e..49ac2638f 100644
--- a/src/main/java/com/easypost/service/RefundService.java
+++ b/src/main/java/com/easypost/service/RefundService.java
@@ -91,7 +91,7 @@ public RefundCollection getNextPage(RefundCollection collection) throws EndOfPag
      */
     public RefundCollection getNextPage(RefundCollection collection, Integer pageSize) throws EndOfPaginationError {
         return collection.getNextPage(new Function<Map<String, Object>, RefundCollection>() {
-            @SneakyThrows
+            @Override @SneakyThrows
             public RefundCollection apply(Map<String, Object> parameters) {
                 return all(parameters);
             }
diff --git a/src/main/java/com/easypost/service/ReportService.java b/src/main/java/com/easypost/service/ReportService.java
index b2da1b402..1e029eb83 100644
--- a/src/main/java/com/easypost/service/ReportService.java
+++ b/src/main/java/com/easypost/service/ReportService.java
@@ -119,7 +119,7 @@ public ReportCollection getNextPage(ReportCollection collection) throws EndOfPag
      */
     public ReportCollection getNextPage(ReportCollection collection, Integer pageSize) throws EndOfPaginationError {
         return collection.getNextPage(new Function<Map<String, Object>, ReportCollection>() {
-            @SneakyThrows
+            @Override @SneakyThrows
             public ReportCollection apply(Map<String, Object> parameters) {
                 return all(parameters);
             }
diff --git a/src/main/java/com/easypost/service/ScanformService.java b/src/main/java/com/easypost/service/ScanformService.java
index 5d275e056..a3f95e07a 100644
--- a/src/main/java/com/easypost/service/ScanformService.java
+++ b/src/main/java/com/easypost/service/ScanformService.java
@@ -83,7 +83,7 @@ public ScanFormCollection getNextPage(ScanFormCollection collection) throws EndO
      */
     public ScanFormCollection getNextPage(ScanFormCollection collection, Integer pageSize) throws EndOfPaginationError {
         return collection.getNextPage(new Function<Map<String, Object>, ScanFormCollection>() {
-            @SneakyThrows
+            @Override @SneakyThrows
             public ScanFormCollection apply(Map<String, Object> parameters) {
                 return all(parameters);
             }
diff --git a/src/main/java/com/easypost/service/ShipmentService.java b/src/main/java/com/easypost/service/ShipmentService.java
index f317535d5..e033352e3 100644
--- a/src/main/java/com/easypost/service/ShipmentService.java
+++ b/src/main/java/com/easypost/service/ShipmentService.java
@@ -90,6 +90,7 @@ public ShipmentCollection all(final Map<String, Object> params) throws EasyPostE
         ShipmentCollection shipmentCollection = Requestor.request(RequestMethod.GET, endpoint, params,
                 ShipmentCollection.class, client);
         // we store the params in the collection so that we can use them to get the next page
+
         shipmentCollection.setPurchased(InternalUtilities.getOrDefault(params, "purchased", null));
         shipmentCollection.setIncludeChildren(InternalUtilities.getOrDefault(params, "include_children", null));
 
@@ -117,7 +118,7 @@ public ShipmentCollection getNextPage(ShipmentCollection collection) throws EndO
      */
     public ShipmentCollection getNextPage(ShipmentCollection collection, Integer pageSize) throws EndOfPaginationError {
         return collection.getNextPage(new Function<Map<String, Object>, ShipmentCollection>() {
-            @SneakyThrows
+            @Override @SneakyThrows
             public ShipmentCollection apply(Map<String, Object> parameters) {
                 return all(parameters);
             }
@@ -397,8 +398,7 @@ public Shipment insure(final String id, final Map<String, Object> params) throws
      *                         filtering.
      * @return lowest SmartRate object
      * @throws EasyPostException when the request fails.
-     * @deprecated use {@link #lowestSmartRate(String, int, SmartrateAccuracy)}
-     * instead.
+     * @deprecated use {@link #lowestSmartRate(String, int, SmartrateAccuracy)} instead.
      * Deprecated: v5.5.0 - v7.0.0
      */
     @Deprecated
@@ -449,8 +449,7 @@ public List<SmartRate> getSmartrates(final String id) throws EasyPostException {
      *                         filtering.
      * @return lowest SmartRate object
      * @throws EasyPostException when the request fails.
-     * @deprecated Use {@link #findLowestSmartrate(List, int, SmartrateAccuracy)}
-     * instead.
+     * @deprecated Use {@link #findLowestSmartrate(List, int, SmartrateAccuracy)} instead.
      * Deprecated: v5.5.0 - v7.0.0
      */
     @Deprecated
@@ -532,7 +531,7 @@ public Shipment generateForm(final String id, final String formType, final Map<S
      * @param id              The id of the shipment.
      * @param plannedShipDate The planned shipment date.
      * @return EstimatedDeliveryDate object.
-     * @throws EasyPostException
+     * @throws EasyPostException When the request fails.
      */
     public List<EstimatedDeliveryDate> retrieveEstimatedDeliveryDate(final String id, final String plannedShipDate)
             throws EasyPostException {
diff --git a/src/main/java/com/easypost/service/TrackerService.java b/src/main/java/com/easypost/service/TrackerService.java
index f8409b8f1..d5f2ca7a9 100644
--- a/src/main/java/com/easypost/service/TrackerService.java
+++ b/src/main/java/com/easypost/service/TrackerService.java
@@ -94,7 +94,7 @@ public TrackerCollection getNextPage(TrackerCollection collection) throws EndOfP
      */
     public TrackerCollection getNextPage(TrackerCollection collection, Integer pageSize) throws EndOfPaginationError {
         return collection.getNextPage(new Function<Map<String, Object>, TrackerCollection>() {
-            @SneakyThrows
+            @Override @SneakyThrows
             public TrackerCollection apply(Map<String, Object> parameters) {
                 return all(parameters);
             }
diff --git a/src/main/java/com/easypost/utils/Utilities.java b/src/main/java/com/easypost/utils/Utilities.java
index 9044dd665..849ad0a44 100644
--- a/src/main/java/com/easypost/utils/Utilities.java
+++ b/src/main/java/com/easypost/utils/Utilities.java
@@ -147,9 +147,8 @@ public static Event validateWebhook(byte[] eventBody, Map<String, Object> header
      *                         filtering.
      * @return lowest Smartrate object
      * @throws EasyPostException when the request fails.
-     * @deprecated Use {@link #findLowestSmartrate(List, int, SmartrateAccuracy)}
-     *             instead.
-     *             Deprecated: v5.5.0 - v7.0.0
+     * @deprecated Use {@link #findLowestSmartrate(List, int, SmartrateAccuracy)} instead.
+     * Deprecated: v5.5.0 - v7.0.0
      */
     @Deprecated
     public static SmartRate getLowestSmartRate(final List<SmartRate> smartrates, int deliveryDay,
diff --git a/src/test/java/com/easypost/BetaRateTest.java b/src/test/java/com/easypost/BetaRateTest.java
index 95c6d2008..00428c109 100644
--- a/src/test/java/com/easypost/BetaRateTest.java
+++ b/src/test/java/com/easypost/BetaRateTest.java
@@ -40,7 +40,7 @@ public void testRetrieveStatelessRates() throws EasyPostException {
 
         List<StatelessRate> rates = vcr.client.betaRate.retrieveStatelessRates(shipment);
 
-        assertTrue(rates.stream().allMatch(rate -> rate instanceof StatelessRate));
+        assertTrue(rates.stream().allMatch(rate -> rate != null));
     }
 
     /**
diff --git a/src/test/java/com/easypost/BetaReferralCustomerTest.java b/src/test/java/com/easypost/BetaReferralCustomerTest.java
index b25e53907..7e2b02623 100644
--- a/src/test/java/com/easypost/BetaReferralCustomerTest.java
+++ b/src/test/java/com/easypost/BetaReferralCustomerTest.java
@@ -24,7 +24,7 @@ public static void setup() throws EasyPostException {
     /**
      * Test add Stripe payment method for referral customer.
      *
-     * @throws EasyPostException
+     * @throws EasyPostException When the request fails.
      */
     @Test
     public void testAddPaymentMethod() throws EasyPostException {
diff --git a/src/test/java/com/easypost/Fixtures.java b/src/test/java/com/easypost/Fixtures.java
index 244c15ae9..62e7c523e 100644
--- a/src/test/java/com/easypost/Fixtures.java
+++ b/src/test/java/com/easypost/Fixtures.java
@@ -7,6 +7,7 @@
 
 import java.io.IOException;
 import java.lang.reflect.Type;
+import java.nio.charset.Charset;
 import java.nio.charset.StandardCharsets;
 import java.nio.file.Files;
 import java.nio.file.Path;
@@ -279,7 +280,8 @@ public static byte[] eventBytes() {
         byte[] data = null;
 
         try {
-            data = Files.readAllLines(Paths.get(fullFilePath), StandardCharsets.UTF_8).get(0).getBytes();
+            data = Files.readAllLines(Paths.get(fullFilePath), StandardCharsets.UTF_8)
+                .get(0).getBytes(Charset.defaultCharset());
         } catch (IOException error) {
             error.printStackTrace();
         }
diff --git a/src/test/java/com/easypost/HookTest.java b/src/test/java/com/easypost/HookTest.java
index 0b72ace97..0e6e6ea12 100644
--- a/src/test/java/com/easypost/HookTest.java
+++ b/src/test/java/com/easypost/HookTest.java
@@ -29,11 +29,10 @@ public static void setup() throws EasyPostException {
     /**
      * Test failing a hook if we subscribed to a request hook.
      *
-     * @param datas The RequestHookResponses object representing the hook data.
+     * @param data The RequestHookResponses object representing the hook data.
      * @return The result of the test.
-     * @throws EasyPostException when the request fails.
      */
-    public static Object failIfSubscribedToRequest(RequestHookResponses datas) {
+    public static Object failIfSubscribedToRequest(RequestHookResponses data) {
         fail("Test failed");
 
         return false;
@@ -42,11 +41,10 @@ public static Object failIfSubscribedToRequest(RequestHookResponses datas) {
     /**
      * Test failing a hook if we subscribed to a response hook.
      *
-     * @param datas The ResponseHookResponses object representing the hook data.
+     * @param data The ResponseHookResponses object representing the hook data.
      * @return The result of the test.
-     * @throws EasyPostException when the request fails.
      */
-    public static Object failIfSubscribedToResponse(ResponseHookResponses datas) {
+    public static Object failIfSubscribedToResponse(ResponseHookResponses data) {
         fail("Test failed");
 
         return false;
@@ -55,17 +53,16 @@ public static Object failIfSubscribedToResponse(ResponseHookResponses datas) {
     /**
      * Test subscribing a request hook.
      *
-     * @param datas The RequestHookResponses object representing the hook data.
+     * @param data The RequestHookResponses object representing the hook data.
      * @return The result of the test.
-     * @throws EasyPostException when the request fails.
      */
-    public static Object testRequestHooks(RequestHookResponses datas) {
-        assertEquals("https://api.easypost.com/v2/parcels", datas.getPath());
-        assertEquals("POST", datas.getMethod());
-        assertNotNull(datas.getHeaders());
-        assertNotNull(datas.getRequestBody());
-        assertNotNull(datas.getRequestTimestamp());
-        assertNotNull(datas.getRequestUuid());
+    public static Object testRequestHooks(RequestHookResponses data) {
+        assertEquals("https://api.easypost.com/v2/parcels", data.getPath());
+        assertEquals("POST", data.getMethod());
+        assertNotNull(data.getHeaders());
+        assertNotNull(data.getRequestBody());
+        assertNotNull(data.getRequestTimestamp());
+        assertNotNull(data.getRequestUuid());
 
         return true;
     }
@@ -73,19 +70,18 @@ public static Object testRequestHooks(RequestHookResponses datas) {
     /**
      * Test subscribing a response hook.
      *
-     * @param datas The ResponseHookResponses object representing the hook data.
+     * @param data The ResponseHookResponses object representing the hook data.
      * @return The result of the test.
-     * @throws EasyPostException when the request fails.
      */
-    public static Object testResponseHooks(ResponseHookResponses datas) {
-        assertEquals("https://api.easypost.com/v2/parcels", datas.getPath());
-        assertEquals("POST", datas.getMethod());
-        assertEquals(201, datas.getHttpStatus());
-        assertNotNull(datas.getHeaders());
-        assertNotNull(datas.getResponseBody());
-        assertNotNull(datas.getRequestTimestamp());
-        assertNotNull(datas.getRequestTimestamp());
-        assertNotNull(datas.getRequestUuid());
+    public static Object testResponseHooks(ResponseHookResponses data) {
+        assertEquals("https://api.easypost.com/v2/parcels", data.getPath());
+        assertEquals("POST", data.getMethod());
+        assertEquals(201, data.getHttpStatus());
+        assertNotNull(data.getHeaders());
+        assertNotNull(data.getResponseBody());
+        assertNotNull(data.getRequestTimestamp());
+        assertNotNull(data.getRequestTimestamp());
+        assertNotNull(data.getRequestUuid());
 
         return true;
     }