Sync/upstream main 2026 03 23

.github/workflows/validation.yml

@@ -23,13 +23,13 @@ jobs:
         uses: actions/checkout@v6
 
       - name: Set up Java ${{ matrix.java-version }}
-        uses: actions/setup-java@v4
+        uses: actions/setup-java@v5
         with:
           distribution: temurin
           java-version: ${{ matrix.java-version }}
 
       - name: Cache Maven packages
-        uses: actions/cache@v3
+        uses: actions/cache@v5
         with:
           path: ~/.m2/repository
           key: ${{ runner.os }}-maven-${{ matrix.java-version }}-${{ hashFiles('**/pom.xml') }}

.release-please-manifest.json

@@ -1,4 +1,3 @@
 {
-    ".": "0.9.0"
+    ".": "1.0.0-rc.1"
 }
-

CHANGELOG.md

@@ -1,5 +1,48 @@
 # Changelog
 
+## [1.0.0-rc.1](https://github.com/google/adk-java/compare/v0.9.0...v1.0.0-rc.1) (2026-03-20)
+
+
+### ⚠ BREAKING CHANGES
+
+* remove McpToolset constructors taking Optional parameters
+* remove deprecated Example processor
+
+### Features
+
+* add handling the a2a metadata in the RemoteA2AAgent; Add the enum type for the metadata keys ([e51f911](https://github.com/google/adk-java/commit/e51f9112050955657da0dfc3aedc00f90ad739ec))
+* add type-safe runAsync methods to BaseTool ([b8cb7e2](https://github.com/google/adk-java/commit/b8cb7e2db6d5ce20f4d7a1b237bdc155563cf4bd))
+* Enhance LangChain4j to support MCP tools with parametersJsonSchema ([2c71ba1](https://github.com/google/adk-java/commit/2c71ba1332e052189115cd4644b7a473c31ed414))
+* fixing context propagation for agent transfers ([9a08076](https://github.com/google/adk-java/commit/9a080763d83c319f539d1bacac4595d13b299e7e))
+* Implement basic version of BigQuery Agent Analytics Plugin ([c8ab0f9](https://github.com/google/adk-java/commit/c8ab0f96b09a6c9636728d634c62695fcd622246))
+* init AGENTS.md file ([7ebeb07](https://github.com/google/adk-java/commit/7ebeb07bf2ee72475484d8a31ccf7b4c601dda96))
+* Propagating the otel context ([8556d4a](https://github.com/google/adk-java/commit/8556d4af16ff04c6e3b678dcfc3d4bb232abc550))
+* remove McpToolset constructors taking Optional parameters ([dbb1394](https://github.com/google/adk-java/commit/dbb139439d38157b4b9af38c52824b1e8405a495))
+* Return List instead of ImmutableList in CallbackUtil methods ([8af5e03](https://github.com/google/adk-java/commit/8af5e03811dfd548830df43103c81a592c8bf361))
+* update requestedAuthConfigs and its builder to be of general Map types ([f145c74](https://github.com/google/adk-java/commit/f145c744482b6b25f29a0b718bd452065e39d930))
+* Update return type of App.plugins() from ImmutableList to List ([8ba4bfe](https://github.com/google/adk-java/commit/8ba4bfed3fa7045f3344329de7a39acddc64ee30))
+* Update return type of toolsets() from ImmutableList to List ([cd56902](https://github.com/google/adk-java/commit/cd56902b803d4f7a1f3c718529842823d9e4370a))
+* update Session.state() and its builder to be of general Map types ([4b9b99a](https://github.com/google/adk-java/commit/4b9b99ae7149a465ba2ae9b7496e01f669786553))
+* update stateDelta builder input to Map from ConcurrentMap ([0d1e5c7](https://github.com/google/adk-java/commit/0d1e5c7b0c42cea66b178cf8fedf08a8c20f7fd0))
+
+
+### Bug Fixes
+
+* fix null handling in runAsyncImpl ([567fdf0](https://github.com/google/adk-java/commit/567fdf048fee49afc86ca5d7d35f55424a6016ba))
+* improve processRequest_concurrentReadAndWrite_noException test case ([4eb3613](https://github.com/google/adk-java/commit/4eb3613b65cb1334e9432960d0f864ef09829c23))
+* include saveArtifact invocations in event chain ([551c31f](https://github.com/google/adk-java/commit/551c31f495aafde8568461cc0aa0973d7df7e5ac))
+* prevent ConcurrentModificationException when session events are modified by another thread during iteration ([fca43fb](https://github.com/google/adk-java/commit/fca43fbb9684ec8d080e437761f6bb4e38adf255))
+* Relaxing constraints for output schema ([d7e03ee](https://github.com/google/adk-java/commit/d7e03eeb067b83abd2afa3ea9bb5fc1c16143245))
+* Removing deprecated methods in Runner ([0af82e6](https://github.com/google/adk-java/commit/0af82e61a3c0dbbd95166a10b450cb507115ab60))
+* Use ConcurrentHashMap in InvocationReplayState ([94de7f1](https://github.com/google/adk-java/commit/94de7f199f86b39bdb7cce6e9800eb05008a8953)), closes [#1009](https://github.com/google/adk-java/issues/1009)
+* workaround for the client config streaming settings are not respected ([#983](https://github.com/google/adk-java/issues/983)) ([3ba04d3](https://github.com/google/adk-java/commit/3ba04d33dc8f2ef8b151abe1be4d1c8b7afcc25a))
+
+
+### Miscellaneous Chores
+
+* remove deprecated Example processor ([28a8cd0](https://github.com/google/adk-java/commit/28a8cd04ca9348dbe51a15d2be3a2b5307394174))
+* set version to 1.0.0-rc.1 ([dc5d794](https://github.com/google/adk-java/commit/dc5d794c066571c7d87f006767bd32298e2a3ba8))
+
 ## [0.9.0](https://github.com/google/adk-java/compare/v0.8.0...v0.9.0) (2026-03-13)
 
 

README.md

@@ -50,13 +50,13 @@ If you're using Maven, add the following to your dependencies:
 <dependency>
   <groupId>com.google.adk</groupId>
   <artifactId>google-adk</artifactId>
-  <version>0.9.0</version>
+  <version>1.0.0-rc.1</version>
 </dependency>
 <!-- Dev UI -->
 <dependency>
     <groupId>com.google.adk</groupId>
     <artifactId>google-adk-dev</artifactId>
-    <version>0.9.0</version>
+    <version>1.0.0-rc.1</version>
 </dependency>
 ```
 

a2a/pom.xml

@@ -5,7 +5,7 @@
   <parent>
     <groupId>com.google.adk</groupId>
     <artifactId>google-adk-parent</artifactId>
-    <version>0.9.1-SNAPSHOT</version><!-- {x-version-update:google-adk:current} -->
+    <version>1.0.1-rc.1-SNAPSHOT</version><!-- {x-version-update:google-adk:current} -->
   </parent>
 
   <artifactId>google-adk-a2a</artifactId>

a2a/src/main/java/com/google/adk/a2a/agent/RemoteA2AAgent.java

@@ -117,7 +117,7 @@ private RemoteA2AAgent(Builder builder) {
     if (this.description.isEmpty() && this.agentCard.description() != null) {
       this.description = this.agentCard.description();
     }
-    this.streaming = this.agentCard.capabilities().streaming();
+    this.streaming = builder.streaming && this.agentCard.capabilities().streaming();
   }
 
   public static Builder builder() {
@@ -133,6 +133,13 @@ public static class Builder {
     private List<? extends BaseAgent> subAgents;
     private List<Callbacks.BeforeAgentCallback> beforeAgentCallback;
     private List<Callbacks.AfterAgentCallback> afterAgentCallback;
+    private boolean streaming;
+
+    @CanIgnoreReturnValue
+    public Builder streaming(boolean streaming) {
+      this.streaming = streaming;
+      return this;
+    }
 
     @CanIgnoreReturnValue
     public Builder name(String name) {
@@ -181,6 +188,10 @@ public RemoteA2AAgent build() {
     }
   }
 
+  public boolean isStreaming() {
+    return streaming;
+  }
+
   private Message.Builder newA2AMessage(Message.Role role, List<io.a2a.spec.Part<?>> parts) {
     return new Message.Builder().messageId(UUID.randomUUID().toString()).role(role).parts(parts);
   }

a2a/src/main/java/com/google/adk/a2a/converters/A2AMetadataKey.java

@@ -0,0 +1,40 @@
+/*
+ * Copyright 2026 Google LLC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.google.adk.a2a.converters;
+
+/**
+ * Enum for the type of A2A metadata. Adds a prefix used to differentiage ADK-related values stored
+ * in Metadata an A2A event.
+ */
+public enum A2AMetadataKey {
+  TYPE("type"),
+  IS_LONG_RUNNING("is_long_running"),
+  PARTIAL("partial"),
+  GROUNDING_METADATA("grounding_metadata"),
+  USAGE_METADATA("usage_metadata"),
+  CUSTOM_METADATA("custom_metadata"),
+  ERROR_CODE("error_code");
+
+  private final String type;
+
+  private A2AMetadataKey(String type) {
+    this.type = "adk_" + type;
+  }
+
+  public String getType() {
+    return type;
+  }
+}

a2a/src/main/java/com/google/adk/a2a/converters/AdkMetadataKey.java

@@ -0,0 +1,35 @@
+/*
+ * Copyright 2026 Google LLC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.google.adk.a2a.converters;
+
+/**
+ * Enum for the type of ADK metadata. Adds a prefix used to differentiate A2A-related values stored
+ * in custom metadata of an ADK session event.
+ */
+public enum AdkMetadataKey {
+  TASK_ID("task_id"),
+  CONTEXT_ID("context_id");
+
+  private final String type;
+
+  private AdkMetadataKey(String type) {
+    this.type = "a2a:" + type;
+  }
+
+  public String getType() {
+    return type;
+  }
+}

a2a/src/main/java/com/google/adk/a2a/converters/PartConverter.java

@@ -52,11 +52,7 @@ public final class PartConverter {
 
   private static final Logger logger = LoggerFactory.getLogger(PartConverter.class);
   private static final ObjectMapper objectMapper = new ObjectMapper();
-  // Constants for metadata types. By convention metadata keys are prefixed with "adk_" to align
-  // with the Python and Golang libraries.
-  public static final String A2A_DATA_PART_METADATA_TYPE_KEY = "adk_type";
-  public static final String A2A_DATA_PART_METADATA_IS_LONG_RUNNING_KEY = "adk_is_long_running";
-  public static final String A2A_DATA_PART_METADATA_IS_PARTIAL_KEY = "adk_partial";
+  // Constants for metadata types.
   public static final String LANGUAGE_KEY = "language";
   public static final String OUTCOME_KEY = "outcome";
   public static final String CODE_KEY = "code";
@@ -135,7 +131,7 @@ private static com.google.genai.types.Part convertDataPartToGenAiPart(DataPart d
     Map<String, Object> metadata =
         Optional.ofNullable(dataPart.getMetadata()).map(HashMap::new).orElseGet(HashMap::new);
 
-    String metadataType = metadata.getOrDefault(A2A_DATA_PART_METADATA_TYPE_KEY, "").toString();
+    String metadataType = metadata.getOrDefault(A2AMetadataKey.TYPE.getType(), "").toString();
 
     if ((data.containsKey(NAME_KEY) && data.containsKey(ARGS_KEY))
         || metadataType.equals(A2ADataPartMetadataType.FUNCTION_CALL.getType())) {
@@ -218,7 +214,7 @@ private static DataPart createDataPartFromFunctionCall(
     addValueIfPresent(data, WILL_CONTINUE_KEY, functionCall.willContinue());
     addValueIfPresent(data, PARTIAL_ARGS_KEY, functionCall.partialArgs());
 
-    metadata.put(A2A_DATA_PART_METADATA_TYPE_KEY, A2ADataPartMetadataType.FUNCTION_CALL.getType());
+    metadata.put(A2AMetadataKey.TYPE.getType(), A2ADataPartMetadataType.FUNCTION_CALL.getType());
 
     return new DataPart(data.buildOrThrow(), metadata.buildOrThrow());
   }
@@ -245,7 +241,7 @@ private static DataPart createDataPartFromFunctionResponse(
     addValueIfPresent(data, PARTS_KEY, functionResponse.parts());
 
     metadata.put(
-        A2A_DATA_PART_METADATA_TYPE_KEY, A2ADataPartMetadataType.FUNCTION_RESPONSE.getType());
+        A2AMetadataKey.TYPE.getType(), A2ADataPartMetadataType.FUNCTION_RESPONSE.getType());
 
     return new DataPart(data.buildOrThrow(), metadata.buildOrThrow());
   }
@@ -268,7 +264,7 @@ private static DataPart createDataPartFromCodeExecutionResult(
     addValueIfPresent(data, OUTPUT_KEY, codeExecutionResult.output());
 
     metadata.put(
-        A2A_DATA_PART_METADATA_TYPE_KEY, A2ADataPartMetadataType.CODE_EXECUTION_RESULT.getType());
+        A2AMetadataKey.TYPE.getType(), A2ADataPartMetadataType.CODE_EXECUTION_RESULT.getType());
 
     return new DataPart(data.buildOrThrow(), metadata.buildOrThrow());
   }
@@ -290,8 +286,7 @@ private static DataPart createDataPartFromExecutableCode(
             .orElse(Language.Known.LANGUAGE_UNSPECIFIED.toString()));
     addValueIfPresent(data, CODE_KEY, executableCode.code());
 
-    metadata.put(
-        A2A_DATA_PART_METADATA_TYPE_KEY, A2ADataPartMetadataType.EXECUTABLE_CODE.getType());
+    metadata.put(A2AMetadataKey.TYPE.getType(), A2ADataPartMetadataType.EXECUTABLE_CODE.getType());
 
     return new DataPart(data.buildOrThrow(), metadata.buildOrThrow());
   }
@@ -305,7 +300,7 @@ public static io.a2a.spec.Part<?> fromGenaiPart(Part part, boolean isPartial) {
     }
     ImmutableMap.Builder<String, Object> metadata = ImmutableMap.builder();
     if (isPartial) {
-      metadata.put(A2A_DATA_PART_METADATA_IS_PARTIAL_KEY, true);
+      metadata.put(A2AMetadataKey.PARTIAL.getType(), true);
     }
 
     if (part.text().isPresent()) {

a2a/src/main/java/com/google/adk/a2a/converters/RequestConverter.java

@@ -61,8 +61,11 @@ public static Optional<Event> convertA2aMessageToAdkEvent(Message message, Strin
     // Convert each A2A Part to GenAI Part
     if (message.getParts() != null) {
       for (Part<?> a2aPart : message.getParts()) {
-        Optional<com.google.genai.types.Part> genaiPart = PartConverter.toGenaiPart(a2aPart);
-        genaiPart.ifPresent(genaiParts::add);
+        try {
+          genaiParts.add(PartConverter.toGenaiPart(a2aPart));
+        } catch (IllegalArgumentException e) {
+          logger.debug("Skipping unconvertible A2A part: {}", e.getMessage());
+        }
       }
     }
 
@@ -125,15 +128,18 @@ public static ImmutableList<Event> convertAggregatedA2aMessageToAdkEvents(
 
     // Emit exactly one ADK Event per A2A Part, preserving order.
     for (Part<?> a2aPart : message.getParts()) {
-      Optional<com.google.genai.types.Part> genaiPart = PartConverter.toGenaiPart(a2aPart);
-      if (genaiPart.isEmpty()) {
+      com.google.genai.types.Part genaiPart;
+      try {
+        genaiPart = PartConverter.toGenaiPart(a2aPart);
+      } catch (IllegalArgumentException e) {
+        logger.debug("Skipping unconvertible A2A part in aggregate: {}", e.getMessage());
         continue;
       }
 
       String author = extractAuthorFromMetadata(a2aPart);
       String role = determineRoleFromAuthor(author);
 
-      events.add(createEvent(ImmutableList.of(genaiPart.get()), author, role, invocationId));
+      events.add(createEvent(ImmutableList.of(genaiPart), author, role, invocationId));
     }
 
     if (events.isEmpty()) {
@@ -162,8 +168,7 @@ private static String extractAuthorFromMetadata(Part<?> a2aPart) {
     if (a2aPart instanceof DataPart dataPart) {
       Map<String, Object> metadata =
           Optional.ofNullable(dataPart.getMetadata()).orElse(ImmutableMap.of());
-      String type =
-          metadata.getOrDefault(PartConverter.A2A_DATA_PART_METADATA_TYPE_KEY, "").toString();
+      String type = metadata.getOrDefault(A2AMetadataKey.TYPE.getType(), "").toString();
       if (type.equals(A2ADataPartMetadataType.FUNCTION_CALL.getType())) {
         return "model";
       }