Switch to JSpecify annotations

This commit updates the whole Spring Framework codebase to use JSpecify
annotations instead of Spring null-safety annotations with JSR 305
semantics.

JSpecify provides signficant enhancements such as properly defined
specifications, a canonical dependency with no split-package issue,
better tooling, better Kotlin integration and the capability to specify
generic type, array and varargs element null-safety. Generic type
null-safety is not defined by this commit yet and will be specified
later.

A key difference is that Spring null-safety annotations, following
JSR 305 semantics, apply to fields, parameters and return values,
while JSpecify annotations apply to type usages. That's why this
commit moves nullability annotations closer to the type for fields
and return values.

See gh-28797

Author: sdeleuze

build.gradle

@@ -107,7 +107,8 @@ configure([rootProject] + javaProjects) { project ->
 			// Previously there could be a split-package issue between JSR250 and JSR305 javax.annotation packages,
 			// but since 6.0 JSR 250 annotations such as @Resource and @PostConstruct have been replaced by their
 			// JakartaEE equivalents in the jakarta.annotation package.
-			//"https://www.javadoc.io/doc/com.google.code.findbugs/jsr305/3.0.2/"
+			//"https://www.javadoc.io/doc/com.google.code.findbugs/jsr305/3.0.2/",
+			"https://jspecify.dev/docs/api/"
 	] as String[]
 }
 

framework-docs/src/main/kotlin/org/springframework/docs/integration/cache/cachestoreconfigurationcaffeine/CustomCacheConfiguration.kt

@@ -28,9 +28,7 @@ class CustomCacheConfiguration {
 	// tag::snippet[]
 	@Bean
 	fun cacheManager(): CacheManager {
-		return CaffeineCacheManager().apply {
-			cacheNames = listOf("default", "books")
-		}
+		return CaffeineCacheManager("default", "books")
 	}
 	// end::snippet[]
 }

framework-platform/framework-platform.gradle

@@ -131,6 +131,7 @@ dependencies {
 		api("org.htmlunit:htmlunit:4.6.0")
 		api("org.javamoney:moneta:1.4.4")
 		api("org.jruby:jruby:9.4.9.0")
+		api("org.jspecify:jspecify:1.0.0")
 		api("org.junit.support:testng-engine:1.0.5")
 		api("org.mozilla:rhino:1.7.15")
 		api("org.ogce:xpp3:1.1.6")

gradle/spring-module.gradle

@@ -13,8 +13,8 @@ dependencies {
 	jmh 'org.openjdk.jmh:jmh-generator-annprocess:1.37'
 	jmh 'org.openjdk.jmh:jmh-generator-bytecode:1.37'
 	jmh 'net.sf.jopt-simple:jopt-simple'
-	errorprone 'com.uber.nullaway:nullaway:0.10.26'
-	errorprone 'com.google.errorprone:error_prone_core:2.9.0'
+	errorprone 'com.uber.nullaway:nullaway:0.12.2'
+	errorprone 'com.google.errorprone:error_prone_core:2.35.1'
 }
 
 pluginManager.withPlugin("kotlin") {

integration-tests/src/test/java/org/springframework/aop/framework/autoproxy/AdvisorAutoProxyCreatorIntegrationTests.java

@@ -20,6 +20,7 @@
 import java.util.List;
 
 import jakarta.servlet.ServletException;
+import org.jspecify.annotations.Nullable;
 import org.junit.jupiter.api.Test;
 
 import org.springframework.aop.support.AopUtils;
@@ -31,7 +32,6 @@
 import org.springframework.beans.factory.InitializingBean;
 import org.springframework.beans.testfixture.beans.ITestBean;
 import org.springframework.context.support.ClassPathXmlApplicationContext;
-import org.springframework.lang.Nullable;
 import org.springframework.transaction.NoTransactionException;
 import org.springframework.transaction.interceptor.TransactionInterceptor;
 import org.springframework.transaction.testfixture.CallCountingTransactionManager;

spring-aop/src/main/java/org/springframework/aop/AfterReturningAdvice.java

@@ -18,7 +18,7 @@
 
 import java.lang.reflect.Method;
 
-import org.springframework.lang.Nullable;
+import org.jspecify.annotations.Nullable;
 
 /**
  * After returning advice is invoked only on normal method return, not if an

spring-aop/src/main/java/org/springframework/aop/MethodBeforeAdvice.java

@@ -18,7 +18,7 @@
 
 import java.lang.reflect.Method;
 
-import org.springframework.lang.Nullable;
+import org.jspecify.annotations.Nullable;
 
 /**
  * Advice invoked before a method is invoked. Such advices cannot

spring-aop/src/main/java/org/springframework/aop/ProxyMethodInvocation.java

@@ -17,8 +17,7 @@
 package org.springframework.aop;
 
 import org.aopalliance.intercept.MethodInvocation;
-
-import org.springframework.lang.Nullable;
+import org.jspecify.annotations.Nullable;
 
 /**
  * Extension of the AOP Alliance {@link org.aopalliance.intercept.MethodInvocation}
@@ -83,7 +82,6 @@ public interface ProxyMethodInvocation extends MethodInvocation {
 	 * @return the value of the attribute, or {@code null} if not set
 	 * @see #setUserAttribute
 	 */
-	@Nullable
-	Object getUserAttribute(String key);
+	@Nullable Object getUserAttribute(String key);
 
 }

spring-aop/src/main/java/org/springframework/aop/TargetClassAware.java

@@ -16,7 +16,7 @@
 
 package org.springframework.aop;
 
-import org.springframework.lang.Nullable;
+import org.jspecify.annotations.Nullable;
 
 /**
  * Minimal interface for exposing the target class behind a proxy.
@@ -36,7 +36,6 @@ public interface TargetClassAware {
 	 * (typically a proxy configuration or an actual proxy).
 	 * @return the target Class, or {@code null} if not known
 	 */
-	@Nullable
-	Class<?> getTargetClass();
+	@Nullable Class<?> getTargetClass();
 
 }

spring-aop/src/main/java/org/springframework/aop/TargetSource.java

@@ -16,7 +16,7 @@
 
 package org.springframework.aop;
 
-import org.springframework.lang.Nullable;
+import org.jspecify.annotations.Nullable;
 
 /**
  * A {@code TargetSource} is used to obtain the current "target" of
@@ -42,8 +42,7 @@ public interface TargetSource extends TargetClassAware {
 	 * @return the type of targets returned by this {@link TargetSource}
 	 */
 	@Override
-	@Nullable
-	Class<?> getTargetClass();
+	@Nullable Class<?> getTargetClass();
 
 	/**
 	 * Will all calls to {@link #getTarget()} return the same object?
@@ -64,8 +63,7 @@ default boolean isStatic() {
 	 * or {@code null} if there is no actual target instance
 	 * @throws Exception if the target object can't be resolved
 	 */
-	@Nullable
-	Object getTarget() throws Exception;
+	@Nullable Object getTarget() throws Exception;
 
 	/**
 	 * Release the given target object obtained from the