Merge spring updates to planner

contrib/planners/pom.xml

@@ -0,0 +1,65 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!--
+ Copyright 2025 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.
+-->
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+    <modelVersion>4.0.0</modelVersion>
+
+    <parent>
+        <groupId>com.google.adk</groupId>
+        <artifactId>google-adk-parent</artifactId>
+        <version>0.5.1-SNAPSHOT</version><!-- {x-version-update:google-adk:current} -->
+        <relativePath>../../pom.xml</relativePath>
+    </parent>
+
+    <artifactId>google-adk-planners</artifactId>
+    <name>Agent Development Kit - Planners</name>
+    <description>Built-in planner implementations for the ADK PlannerAgent, including GOAP (Goal-Oriented Action Planning), P2P (Peer-to-Peer), and Supervisor planners.</description>
+
+    <dependencies>
+        <!-- Main dependencies -->
+        <dependency>
+            <groupId>com.google.adk</groupId>
+            <artifactId>google-adk</artifactId>
+            <version>${project.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>com.google.genai</groupId>
+            <artifactId>google-genai</artifactId>
+        </dependency>
+
+        <!-- Test dependencies -->
+        <dependency>
+            <groupId>org.junit.jupiter</groupId>
+            <artifactId>junit-jupiter-api</artifactId>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>org.junit.jupiter</groupId>
+            <artifactId>junit-jupiter-engine</artifactId>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>com.google.truth</groupId>
+            <artifactId>truth</artifactId>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>org.mockito</groupId>
+            <artifactId>mockito-core</artifactId>
+            <scope>test</scope>
+        </dependency>
+    </dependencies>
+</project>

contrib/planners/src/main/java/com/google/adk/planner/LoopPlanner.java

@@ -0,0 +1,90 @@
+/*
+ * Copyright 2025 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.planner;
+
+import com.google.adk.agents.BaseAgent;
+import com.google.adk.agents.Planner;
+import com.google.adk.agents.PlannerAction;
+import com.google.adk.agents.PlanningContext;
+import com.google.adk.events.Event;
+import com.google.common.collect.ImmutableList;
+import io.reactivex.rxjava3.core.Single;
+import java.util.List;
+import java.util.concurrent.atomic.AtomicInteger;
+
+/**
+ * A planner that cycles through sub-agents repeatedly, stopping when an escalate event is detected
+ * or the maximum number of cycles is reached.
+ */
+public final class LoopPlanner implements Planner {
+
+  private final int maxCycles;
+  private final AtomicInteger cursor = new AtomicInteger(0);
+  private final AtomicInteger cycleCount = new AtomicInteger(0);
+  private ImmutableList<BaseAgent> agents;
+
+  public LoopPlanner(int maxCycles) {
+    this.maxCycles = maxCycles;
+  }
+
+  @Override
+  public void init(PlanningContext context) {
+    agents = context.availableAgents();
+    cursor.set(0);
+    cycleCount.set(0);
+  }
+
+  @Override
+  public Single<PlannerAction> firstAction(PlanningContext context) {
+    cursor.set(0);
+    cycleCount.set(0);
+    return selectNext(context);
+  }
+
+  @Override
+  public Single<PlannerAction> nextAction(PlanningContext context) {
+    if (hasEscalateEvent(context.events())) {
+      return Single.just(new PlannerAction.Done());
+    }
+    return selectNext(context);
+  }
+
+  private Single<PlannerAction> selectNext(PlanningContext context) {
+    if (agents == null || agents.isEmpty()) {
+      return Single.just(new PlannerAction.Done());
+    }
+
+    int idx = cursor.getAndIncrement();
+    if (idx >= agents.size()) {
+      int cycle = cycleCount.incrementAndGet();
+      if (cycle >= maxCycles) {
+        return Single.just(new PlannerAction.Done());
+      }
+      cursor.set(1);
+      idx = 0;
+    }
+    return Single.just(new PlannerAction.RunAgents(agents.get(idx)));
+  }
+
+  private static boolean hasEscalateEvent(List<Event> events) {
+    if (events.isEmpty()) {
+      return false;
+    }
+    Event lastEvent = events.get(events.size() - 1);
+    return lastEvent.actions().escalate().orElse(false);
+  }
+}

contrib/planners/src/main/java/com/google/adk/planner/ParallelPlanner.java

@@ -0,0 +1,39 @@
+/*
+ * Copyright 2025 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.planner;
+
+import com.google.adk.agents.Planner;
+import com.google.adk.agents.PlannerAction;
+import com.google.adk.agents.PlanningContext;
+import io.reactivex.rxjava3.core.Single;
+
+/** A planner that runs all sub-agents in parallel, then completes. */
+public final class ParallelPlanner implements Planner {
+
+  @Override
+  public Single<PlannerAction> firstAction(PlanningContext context) {
+    if (context.availableAgents().isEmpty()) {
+      return Single.just(new PlannerAction.Done());
+    }
+    return Single.just(new PlannerAction.RunAgents(context.availableAgents()));
+  }
+
+  @Override
+  public Single<PlannerAction> nextAction(PlanningContext context) {
+    return Single.just(new PlannerAction.Done());
+  }
+}

contrib/planners/src/main/java/com/google/adk/planner/SequentialPlanner.java

@@ -0,0 +1,57 @@
+/*
+ * Copyright 2025 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.planner;
+
+import com.google.adk.agents.BaseAgent;
+import com.google.adk.agents.Planner;
+import com.google.adk.agents.PlannerAction;
+import com.google.adk.agents.PlanningContext;
+import com.google.common.collect.ImmutableList;
+import io.reactivex.rxjava3.core.Single;
+import java.util.concurrent.atomic.AtomicInteger;
+
+/** A planner that runs sub-agents one at a time in order. */
+public final class SequentialPlanner implements Planner {
+
+  private final AtomicInteger cursor = new AtomicInteger(0);
+  private ImmutableList<BaseAgent> agents;
+
+  @Override
+  public void init(PlanningContext context) {
+    agents = context.availableAgents();
+    cursor.set(0);
+  }
+
+  @Override
+  public Single<PlannerAction> firstAction(PlanningContext context) {
+    cursor.set(0);
+    return selectNext();
+  }
+
+  @Override
+  public Single<PlannerAction> nextAction(PlanningContext context) {
+    return selectNext();
+  }
+
+  private Single<PlannerAction> selectNext() {
+    int idx = cursor.getAndIncrement();
+    if (agents == null || idx >= agents.size()) {
+      return Single.just(new PlannerAction.Done());
+    }
+    return Single.just(new PlannerAction.RunAgents(agents.get(idx)));
+  }
+}