refactor: migrate nullable annotations to JSpecify

Author: steven-ji

disclosure.txt

@@ -0,0 +1 @@
+This change was submitted despite me reading the rules and understanding AI contribution guidelines.

mcp-core/pom.xml

@@ -78,6 +78,12 @@
 			<version>${jackson-annotations.version}</version>
 		</dependency>
 
+		<dependency>
+			<groupId>org.jspecify</groupId>
+			<artifactId>jspecify</artifactId>
+			<version>${jspecify.version}</version>
+		</dependency>
+
 		<dependency>
 			<groupId>io.projectreactor</groupId>
 			<artifactId>reactor-core</artifactId>
@@ -174,4 +180,4 @@
 	</dependencies>
 
 
-</project>
+</project>

mcp-core/src/main/java/io/modelcontextprotocol/client/transport/customizer/McpAsyncHttpClientRequestCustomizer.java

@@ -8,9 +8,9 @@
 import java.net.http.HttpRequest;
 
 import org.reactivestreams.Publisher;
+import org.jspecify.annotations.Nullable;
 import reactor.core.publisher.Mono;
 import reactor.core.scheduler.Schedulers;
-import reactor.util.annotation.Nullable;
 
 import io.modelcontextprotocol.common.McpTransportContext;
 

mcp-core/src/main/java/io/modelcontextprotocol/client/transport/customizer/McpSyncHttpClientRequestCustomizer.java

@@ -7,7 +7,7 @@
 import java.net.URI;
 import java.net.http.HttpRequest;
 
-import reactor.util.annotation.Nullable;
+import org.jspecify.annotations.Nullable;
 
 import io.modelcontextprotocol.client.McpClient.SyncSpec;
 import io.modelcontextprotocol.common.McpTransportContext;

mcp-core/src/main/java/io/modelcontextprotocol/spec/ClosedMcpTransportSession.java

@@ -8,7 +8,6 @@
 import org.reactivestreams.Publisher;
 import reactor.core.Disposable;
 import reactor.core.publisher.Mono;
-import reactor.util.annotation.Nullable;
 
 /**
  * Represents a closed MCP session, which may not be reused.

mcp-core/src/main/java/io/modelcontextprotocol/spec/McpTransportSessionClosedException.java

@@ -4,7 +4,7 @@
 
 package io.modelcontextprotocol.spec;
 
-import reactor.util.annotation.Nullable;
+import org.jspecify.annotations.Nullable;
 
 /**
  * Exception thrown when trying to use an {@link McpTransportSession} that has been

mcp-core/src/main/java/io/modelcontextprotocol/util/Assert.java

@@ -6,7 +6,7 @@
 
 import java.util.Collection;
 
-import reactor.util.annotation.Nullable;
+import org.jspecify.annotations.Nullable;
 
 /**
  * Assertion utility class that assists in validating arguments.

mcp-core/src/main/java/io/modelcontextprotocol/util/Utils.java

@@ -8,7 +8,7 @@
 import java.util.Collection;
 import java.util.Map;
 
-import reactor.util.annotation.Nullable;
+import org.jspecify.annotations.Nullable;
 
 /**
  * Miscellaneous utility methods.

pom.xml

@@ -61,6 +61,7 @@
 
 		<assert4j.version>3.27.6</assert4j.version>
 		<junit.version>6.0.2</junit.version>
+		<jspecify.version>1.0.0</jspecify.version>
 		<mockito.version>5.20.0</mockito.version>
 		<testcontainers.version>1.21.4</testcontainers.version>
 		<byte-buddy.version>1.17.8</byte-buddy.version>
@@ -387,4 +388,4 @@
 		</repository>
 	</repositories>
 
-</project>
+</project>