diff --git a/src/main/java/org/springframework/hateoas/Affordance.java b/src/main/java/org/springframework/hateoas/Affordance.java
index 141b8e44..423dd8d2 100644
--- a/src/main/java/org/springframework/hateoas/Affordance.java
+++ b/src/main/java/org/springframework/hateoas/Affordance.java
@@ -65,12 +65,14 @@ public final class Affordance implements Iterable<AffordanceModel> {
 	}
 
 	@Override
-	public boolean equals(Object o) {
+	public boolean equals(@Nullable Object o) {
 
-		if (this == o)
+		if (this == o) {
 			return true;
-		if (o == null || getClass() != o.getClass())
+		}
+		if (o == null || getClass() != o.getClass()) {
 			return false;
+		}
 		Affordance that = (Affordance) o;
 		return Objects.equals(this.models, that.models);
 	}
@@ -80,6 +82,7 @@ public final class Affordance implements Iterable<AffordanceModel> {
 		return Objects.hash(this.models);
 	}
 
+	@Override
 	public String toString() {
 		return "Affordance(models=" + this.models + ")";
 	}
diff --git a/src/main/java/org/springframework/hateoas/Link.java b/src/main/java/org/springframework/hateoas/Link.java
index 7ca1ff3b..305baadc 100755
--- a/src/main/java/org/springframework/hateoas/Link.java
+++ b/src/main/java/org/springframework/hateoas/Link.java
@@ -699,6 +699,9 @@ public class Link implements Serializable {
 
 	@JsonProperty
 	public UriTemplate getTemplate() {
+
+		UriTemplate template = this.template;
+
 		return template == null ? UriTemplate.of(href) : template;
 	}
 
diff --git a/src/main/java/org/springframework/hateoas/QueryParameter.java b/src/main/java/org/springframework/hateoas/QueryParameter.java
index f043e5b2..404ea2a3 100644
--- a/src/main/java/org/springframework/hateoas/QueryParameter.java
+++ b/src/main/java/org/springframework/hateoas/QueryParameter.java
@@ -38,7 +38,7 @@ public final class QueryParameter {
 	private final @Nullable String value;
 	private final boolean required;
 
-	private QueryParameter(String name, String value, boolean required) {
+	private QueryParameter(String name, @Nullable String value, boolean required) {
 
 		this.name = name;
 		this.value = value;
@@ -97,7 +97,7 @@ public final class QueryParameter {
 
 	/**
 	 * Create a new {@link QueryParameter} by copying all attributes and applying the new {@literal value}.
-	 * 
+	 *
 	 * @param value
 	 * @return
 	 */
@@ -119,12 +119,14 @@ public final class QueryParameter {
 	}
 
 	@Override
-	public boolean equals(Object o) {
+	public boolean equals(@Nullable Object o) {
 
-		if (this == o)
+		if (this == o) {
 			return true;
-		if (o == null || getClass() != o.getClass())
+		}
+		if (o == null || getClass() != o.getClass()) {
 			return false;
+		}
 		QueryParameter that = (QueryParameter) o;
 		return this.required == that.required && Objects.equals(this.name, that.name)
 				&& Objects.equals(this.value, that.value);
@@ -135,6 +137,7 @@ public final class QueryParameter {
 		return Objects.hash(this.name, this.value, this.required);
 	}
 
+	@Override
 	public String toString() {
 		return "QueryParameter(name=" + this.name + ", value=" + this.value + ", required=" + this.required + ")";
 	}
diff --git a/src/main/java/org/springframework/hateoas/TemplateVariables.java b/src/main/java/org/springframework/hateoas/TemplateVariables.java
index 38388725..e50fb4ee 100644
--- a/src/main/java/org/springframework/hateoas/TemplateVariables.java
+++ b/src/main/java/org/springframework/hateoas/TemplateVariables.java
@@ -29,6 +29,7 @@ import java.util.stream.Collectors;
 import java.util.stream.Stream;
 
 import org.springframework.hateoas.TemplateVariable.VariableType;
+import org.springframework.lang.Nullable;
 import org.springframework.util.Assert;
 
 /**
@@ -191,7 +192,7 @@ public final class TemplateVariables implements Iterable<TemplateVariable>, Seri
 	}
 
 	@Override
-	public boolean equals(Object o) {
+	public boolean equals(@Nullable Object o) {
 
 		if (this == o) {
 			return true;
diff --git a/src/main/java/org/springframework/hateoas/client/Hop.java b/src/main/java/org/springframework/hateoas/client/Hop.java
index 9b284b67..0d0ca426 100644
--- a/src/main/java/org/springframework/hateoas/client/Hop.java
+++ b/src/main/java/org/springframework/hateoas/client/Hop.java
@@ -21,6 +21,7 @@ import java.util.Map;
 import java.util.Objects;
 
 import org.springframework.http.HttpHeaders;
+import org.springframework.lang.Nullable;
 import org.springframework.util.Assert;
 
 /**
@@ -57,7 +58,7 @@ public final class Hop {
 
 	/**
 	 * Creates a new {@link Hop} for the given relation name.
-	 * 
+	 *
 	 * @param rel must not be {@literal null} or empty.
 	 * @return
 	 */
@@ -130,7 +131,7 @@ public final class Hop {
 
 	/**
 	 * Returns whether the {@link Hop} has parameters declared.
-	 * 
+	 *
 	 * @return
 	 */
 	boolean hasParameters() {
@@ -169,12 +170,14 @@ public final class Hop {
 	}
 
 	@Override
-	public boolean equals(Object o) {
+	public boolean equals(@Nullable Object o) {
 
-		if (this == o)
+		if (this == o) {
 			return true;
-		if (o == null || getClass() != o.getClass())
+		}
+		if (o == null || getClass() != o.getClass()) {
 			return false;
+		}
 		Hop hop = (Hop) o;
 		return Objects.equals(this.rel, hop.rel) && Objects.equals(this.parameters, hop.parameters)
 				&& Objects.equals(this.headers, hop.headers);
@@ -185,6 +188,7 @@ public final class Hop {
 		return Objects.hash(this.rel, this.parameters, this.headers);
 	}
 
+	@Override
 	public String toString() {
 		return "Hop(rel=" + this.rel + ", parameters=" + this.parameters + ", headers=" + this.headers + ")";
 	}
diff --git a/src/main/java/org/springframework/hateoas/client/Traverson.java b/src/main/java/org/springframework/hateoas/client/Traverson.java
index 19f23f83..2170d061 100644
--- a/src/main/java/org/springframework/hateoas/client/Traverson.java
+++ b/src/main/java/org/springframework/hateoas/client/Traverson.java
@@ -466,12 +466,14 @@ public class Traverson {
 		}
 
 		@Override
-		public boolean equals(Object o) {
+		public boolean equals(@Nullable Object o) {
 
-			if (this == o)
+			if (this == o) {
 				return true;
-			if (o == null || getClass() != o.getClass())
+			}
+			if (o == null || getClass() != o.getClass()) {
 				return false;
+			}
 			UriStringAndHeaders that = (UriStringAndHeaders) o;
 			return Objects.equals(this.uri, that.uri) && Objects.equals(this.httpHeaders, that.httpHeaders);
 		}
@@ -481,6 +483,7 @@ public class Traverson {
 			return Objects.hash(this.uri, this.httpHeaders);
 		}
 
+		@Override
 		public String toString() {
 			return "Traverson.UriStringAndHeaders(uri=" + this.uri + ", httpHeaders=" + this.httpHeaders + ")";
 		}
@@ -509,12 +512,14 @@ public class Traverson {
 		}
 
 		@Override
-		public boolean equals(Object o) {
+		public boolean equals(@Nullable Object o) {
 
-			if (this == o)
+			if (this == o) {
 				return true;
-			if (o == null || getClass() != o.getClass())
+			}
+			if (o == null || getClass() != o.getClass()) {
 				return false;
+			}
 			URIAndHeaders that = (URIAndHeaders) o;
 			return Objects.equals(this.uri, that.uri) && Objects.equals(this.httpHeaders, that.httpHeaders);
 		}
@@ -524,6 +529,7 @@ public class Traverson {
 			return Objects.hash(this.uri, this.httpHeaders);
 		}
 
+		@Override
 		public String toString() {
 			return "Traverson.URIAndHeaders(uri=" + this.uri + ", httpHeaders=" + this.httpHeaders + ")";
 		}
diff --git a/src/main/java/org/springframework/hateoas/mediatype/TypeBasedPayloadMetadata.java b/src/main/java/org/springframework/hateoas/mediatype/TypeBasedPayloadMetadata.java
index ace5ec57..8005f4ca 100644
--- a/src/main/java/org/springframework/hateoas/mediatype/TypeBasedPayloadMetadata.java
+++ b/src/main/java/org/springframework/hateoas/mediatype/TypeBasedPayloadMetadata.java
@@ -28,6 +28,7 @@ import org.springframework.hateoas.AffordanceModel.InputPayloadMetadata;
 import org.springframework.hateoas.AffordanceModel.Named;
 import org.springframework.hateoas.AffordanceModel.PropertyMetadata;
 import org.springframework.http.MediaType;
+import org.springframework.lang.NonNull;
 import org.springframework.util.Assert;
 
 /**
@@ -88,6 +89,11 @@ class TypeBasedPayloadMetadata implements InputPayloadMetadata {
 		return Arrays.asList(type.getName(), type.getSimpleName());
 	}
 
+	/*
+	 * (non-Javadoc)
+	 * @see org.springframework.hateoas.AffordanceModel.PayloadMetadata#getType()
+	 */
+	@NonNull
 	public Class<?> getType() {
 		return this.type;
 	}
diff --git a/src/main/java/org/springframework/hateoas/mediatype/hal/DefaultCurieProvider.java b/src/main/java/org/springframework/hateoas/mediatype/hal/DefaultCurieProvider.java
index 8082642f..e2b92063 100644
--- a/src/main/java/org/springframework/hateoas/mediatype/hal/DefaultCurieProvider.java
+++ b/src/main/java/org/springframework/hateoas/mediatype/hal/DefaultCurieProvider.java
@@ -24,6 +24,7 @@ import org.springframework.hateoas.Link;
 import org.springframework.hateoas.LinkRelation;
 import org.springframework.hateoas.Links;
 import org.springframework.hateoas.UriTemplate;
+import org.springframework.lang.NonNull;
 import org.springframework.lang.Nullable;
 import org.springframework.util.Assert;
 import org.springframework.util.StringUtils;
@@ -160,6 +161,8 @@ public class DefaultCurieProvider implements CurieProvider {
 			this.name = name;
 		}
 
+		@Override
+		@NonNull
 		public String getName() {
 			return this.name;
 		}
diff --git a/src/test/java/org/springframework/hateoas/LinkUnitTest.java b/src/test/java/org/springframework/hateoas/LinkUnitTest.java
index 1a2a290e..3035ed90 100755
--- a/src/test/java/org/springframework/hateoas/LinkUnitTest.java
+++ b/src/test/java/org/springframework/hateoas/LinkUnitTest.java
@@ -307,6 +307,7 @@ class LinkUnitTest {
 	 * @see #671
 	 */
 	@Test
+	@SuppressWarnings("null")
 	void rejectsInvalidRelationsOnHasRel() {
 
 		Link link = Link.of("/");