fix: Update the examples after the latest client changes (#244)

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Author: fjuma

examples/helloworld/client/src/main/java/io/a2a/examples/helloworld/HelloWorldClient.java

@@ -16,6 +16,8 @@
 import io.a2a.client.ClientEvent;
 import io.a2a.client.MessageEvent;
 import io.a2a.client.http.A2ACardResolver;
+import io.a2a.client.transport.jsonrpc.JSONRPCTransport;
+import io.a2a.client.transport.jsonrpc.JSONRPCTransportConfig;
 import io.a2a.spec.AgentCard;
 import io.a2a.spec.Message;
 import io.a2a.spec.Part;
@@ -84,7 +86,9 @@ public static void main(String[] args) {
             Client client = Client
                     .builder(finalAgentCard)
                     .addConsumers(consumers)
-                    .streamingErrorHandler(streamingErrorHandler).build();
+                    .streamingErrorHandler(streamingErrorHandler)
+                    .withTransport(JSONRPCTransport.class, new JSONRPCTransportConfig())
+                    .build();
 
             Message message = A2A.toUserMessage(MESSAGE_TEXT); // the message ID will be automatically generated for you
 

examples/helloworld/server/pom.xml

@@ -22,7 +22,7 @@
         </dependency>
         <dependency>
             <groupId>io.github.a2asdk</groupId>
-            <artifactId>a2a-java-sdk-server-common</artifactId>
+            <artifactId>a2a-java-sdk-reference-jsonrpc</artifactId>
             <version>${project.version}</version>
         </dependency>
         <dependency>

examples/helloworld/server/src/main/java/io/a2a/examples/helloworld/AgentCardProducer.java

@@ -37,7 +37,7 @@ public AgentCard agentCard() {
                                 .tags(Collections.singletonList("hello world"))
                                 .examples(List.of("hi", "hello world"))
                                 .build()))
-                .protocolVersion("0.2.5")
+                .protocolVersion("0.3.0")
                 .build();
     }
 }