Drop support for javax.annotation.NonNull

Closes gh-46773

Author: snicoll

documentation/spring-boot-docs/src/docs/antora/modules/reference/pages/actuator/endpoints.adoc

@@ -413,7 +413,7 @@ Operations on an endpoint receive input through their parameters.
 When exposed over the web, the values for these parameters are taken from the URL's query parameters and from the JSON request body.
 When exposed over JMX, the parameters are mapped to the parameters of the MBean's operations.
 Parameters are required by default.
-They can be made optional by annotating them with either `@javax.annotation.Nullable` or javadoc:org.springframework.lang.Nullable[format=annotation].
+They can be made optional by annotating them with either javadoc:org.springframework.boot.actuate.endpoint.annotation.OptionalParameter[format=annotation] or javadoc:org.springframework.lang.Nullable[format=annotation].
 
 You can map each root property in the JSON request body to a parameter of the endpoint.
 Consider the following JSON request body:
@@ -547,7 +547,7 @@ NOTE: Range requests are not supported when using Jersey.
 ==== Web Endpoint Security
 
 An operation on a web endpoint or a web-specific endpoint extension can receive the current javadoc:java.security.Principal[] or javadoc:org.springframework.boot.actuate.endpoint.SecurityContext[] as a method parameter.
-The former is typically used in conjunction with either `@javax.annotation.Nullable` or javadoc:org.springframework.lang.Nullable[format=annotation] to provide different behavior for authenticated and unauthenticated users.
+The former is typically used in conjunction with either javadoc:org.springframework.boot.actuate.endpoint.annotation.OptionalParameter[format=annotation] or javadoc:org.springframework.lang.Nullable[format=annotation] to provide different behavior for authenticated and unauthenticated users.
 The latter is typically used to perform authorization checks by using its `isUserInRole(String)` method.
 
 

module/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/endpoint/invoke/reflect/OperationMethodParameter.java

@@ -20,13 +20,7 @@
 import java.lang.reflect.Parameter;
 import java.util.function.Predicate;
 
-import javax.annotation.Nonnull;
-import javax.annotation.meta.When;
-
 import org.springframework.boot.actuate.endpoint.invoke.OperationParameter;
-import org.springframework.core.annotation.MergedAnnotation;
-import org.springframework.core.annotation.MergedAnnotations;
-import org.springframework.util.ClassUtils;
 
 /**
  * {@link OperationParameter} created from an {@link OperationMethod}.
@@ -36,8 +30,6 @@
  */
 class OperationMethodParameter implements OperationParameter {
 
-	private static final boolean jsr305Present = ClassUtils.isPresent("javax.annotation.Nonnull", null);
-
 	private final String name;
 
 	private final Parameter parameter;
@@ -68,13 +60,7 @@ public Class<?> getType() {
 
 	@Override
 	public boolean isMandatory() {
-		if (isOptional()) {
-			return false;
-		}
-		if (jsr305Present) {
-			return new Jsr305().isMandatory(this.parameter);
-		}
-		return true;
+		return !isOptional();
 	}
 
 	@SuppressWarnings("deprecation")
@@ -93,13 +79,4 @@ public String toString() {
 		return this.name + " of type " + this.parameter.getType().getName();
 	}
 
-	private static final class Jsr305 {
-
-		boolean isMandatory(Parameter parameter) {
-			MergedAnnotation<Nonnull> annotation = MergedAnnotations.from(parameter).get(Nonnull.class);
-			return !annotation.isPresent() || annotation.getEnum("when", When.class) == When.ALWAYS;
-		}
-
-	}
-
 }

module/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/endpoint/invoke/reflect/OperationMethodParameterTests.java

@@ -24,10 +24,6 @@
 import java.lang.reflect.Method;
 import java.lang.reflect.Parameter;
 
-import javax.annotation.Nonnull;
-import javax.annotation.meta.TypeQualifier;
-import javax.annotation.meta.When;
-
 import org.junit.jupiter.api.Test;
 
 import org.springframework.boot.actuate.endpoint.annotation.Selector;
@@ -50,15 +46,6 @@ class OperationMethodParameterTests {
 	private final Method exampleSpringNullable = ReflectionUtils.findMethod(getClass(), "exampleSpringNullable",
 			String.class, String.class);
 
-	private final Method exampleJsr305 = ReflectionUtils.findMethod(getClass(), "exampleJsr305", String.class,
-			String.class);
-
-	private final Method exampleMetaJsr305 = ReflectionUtils.findMethod(getClass(), "exampleMetaJsr305", String.class,
-			String.class);
-
-	private final Method exampleJsr305NonNull = ReflectionUtils.findMethod(getClass(), "exampleJsr305NonNull",
-			String.class, String.class);
-
 	private Method exampleAnnotation = ReflectionUtils.findMethod(getClass(), "exampleAnnotation", String.class);
 
 	@Test
@@ -96,27 +83,6 @@ void isMandatoryWhenSpringNullableAnnotationShouldReturnFalse() {
 		assertThat(parameter.isMandatory()).isFalse();
 	}
 
-	@Test
-	void isMandatoryWhenJsrNullableAnnotationShouldReturnFalse() {
-		OperationMethodParameter parameter = new OperationMethodParameter("name", this.exampleJsr305.getParameters()[1],
-				this::isOptionalParameter);
-		assertThat(parameter.isMandatory()).isFalse();
-	}
-
-	@Test
-	void isMandatoryWhenJsrMetaNullableAnnotationShouldReturnFalse() {
-		OperationMethodParameter parameter = new OperationMethodParameter("name",
-				this.exampleMetaJsr305.getParameters()[1], this::isOptionalParameter);
-		assertThat(parameter.isMandatory()).isFalse();
-	}
-
-	@Test
-	void isMandatoryWhenJsrNonnullAnnotationShouldReturnTrue() {
-		OperationMethodParameter parameter = new OperationMethodParameter("name",
-				this.exampleJsr305NonNull.getParameters()[1], this::isOptionalParameter);
-		assertThat(parameter.isMandatory()).isTrue();
-	}
-
 	@Test
 	void getAnnotationShouldReturnAnnotation() {
 		OperationMethodParameter parameter = new OperationMethodParameter("name",
@@ -137,25 +103,9 @@ void example(String one, @TestOptional String two) {
 	void exampleSpringNullable(String one, @org.springframework.lang.Nullable String two) {
 	}
 
-	void exampleJsr305(String one, @javax.annotation.Nullable String two) {
-	}
-
-	void exampleMetaJsr305(String one, @MetaNullable String two) {
-	}
-
-	void exampleJsr305NonNull(String one, @javax.annotation.Nonnull String two) {
-	}
-
 	void exampleAnnotation(@Selector(match = Match.ALL_REMAINING) String allRemaining) {
 	}
 
-	@TypeQualifier
-	@Retention(RetentionPolicy.RUNTIME)
-	@Nonnull(when = When.MAYBE)
-	@interface MetaNullable {
-
-	}
-
 	@Target({ ElementType.METHOD, ElementType.PARAMETER, ElementType.FIELD })
 	@Retention(RetentionPolicy.RUNTIME)
 	@Documented