refactor: Fixing minor implementation details in agent/ classes

core/src/main/java/com/google/adk/agents/ActiveStreamingTool.java

@@ -40,40 +40,24 @@ public ActiveStreamingTool(Disposable task, LiveRequestQueue stream) {
 
   public ActiveStreamingTool() {}
 
-  /**
-   * Returns the active task of this streaming tool.
-   *
-   * @return The active task.
-   */
+  /** Returns the active task of this streaming tool. */
   @Nullable
   public Disposable task() {
     return task;
   }
 
-  /**
-   * Sets the active task of this streaming tool.
-   *
-   * @param task The new active task.
-   */
+  /** Sets the active task of this streaming tool. */
   public void task(@Nullable Disposable task) {
     this.task = task;
   }
 
-  /**
-   * Returns the active stream of this streaming tool.
-   *
-   * @return The active stream.
-   */
+  /** Returns the active stream of this streaming tool. */
   @Nullable
   public LiveRequestQueue stream() {
     return stream;
   }
 
-  /**
-   * Sets the active stream of this streaming tool.
-   *
-   * @param stream The new active stream.
-   */
+  /** Sets the active stream of this streaming tool. */
   public void stream(@Nullable LiveRequestQueue stream) {
     this.stream = stream;
   }

core/src/main/java/com/google/adk/agents/ConfigAgentUtils.java

@@ -25,6 +25,7 @@
 import com.fasterxml.jackson.dataformat.yaml.YAMLFactory;
 import com.google.adk.utils.ComponentRegistry;
 import com.google.common.collect.ImmutableList;
+import com.google.common.collect.ImmutableMap;
 import java.io.File;
 import java.io.IOException;
 import java.nio.charset.StandardCharsets;
@@ -47,6 +48,14 @@ public final class ConfigAgentUtils {
 
   private static final Logger logger = LoggerFactory.getLogger(ConfigAgentUtils.class);
 
+  private static final ImmutableMap<Class<? extends BaseAgent>, Class<? extends BaseAgentConfig>>
+      AGENT_TO_CONFIG_CLASS =
+          ImmutableMap.of(
+              LlmAgent.class, LlmAgentConfig.class,
+              SequentialAgent.class, SequentialAgentConfig.class,
+              ParallelAgent.class, ParallelAgentConfig.class,
+              LoopAgent.class, LoopAgentConfig.class);
+
   private ConfigAgentUtils() {}
 
   /**
@@ -294,31 +303,7 @@ private static <T extends BaseAgentConfig> T loadConfigAsType(
    */
   private static Class<? extends BaseAgentConfig> getConfigClassForAgent(
       Class<? extends BaseAgent> agentClass) {
-
-    if (agentClass == LlmAgent.class) {
-      return LlmAgentConfig.class;
-    }
-
-    if (agentClass == SequentialAgent.class) {
-      return SequentialAgentConfig.class;
-    }
-
-    if (agentClass == ParallelAgent.class) {
-      return ParallelAgentConfig.class;
-    }
-
-    if (agentClass == LoopAgent.class) {
-      return LoopAgentConfig.class;
-    }
-
-    // TODO: Add more agent class to config class mappings as needed
-    // Example:
-    // if (agentClass == CustomAgent.class) {
-    //   return CustomAgentConfig.class;
-    // }
-
-    // Default fallback to BaseAgentConfig
-    return BaseAgentConfig.class;
+    return AGENT_TO_CONFIG_CLASS.getOrDefault(agentClass, BaseAgentConfig.class);
   }
 
   /** Exception thrown when configuration is invalid. */

core/src/main/java/com/google/adk/agents/LlmAgent.java

@@ -620,12 +620,11 @@ protected void validate() {
 
       if (this.outputSchema != null) {
         if (!this.disallowTransferToParent || !this.disallowTransferToPeers) {
-          System.err.println(
-              "Warning: Invalid config for agent "
-                  + this.name
-                  + ": outputSchema cannot co-exist with agent transfer"
+          logger.warn(
+              "Invalid config for agent {}: outputSchema cannot co-exist with agent transfer"
                   + " configurations. Setting disallowTransferToParent=true and"
-                  + " disallowTransferToPeers=true.");
+                  + " disallowTransferToPeers=true.",
+              this.name);
           this.disallowTransferToParent = true;
           this.disallowTransferToPeers = true;
         }

core/src/main/java/com/google/adk/agents/ToolResolver.java

@@ -99,7 +99,7 @@ static ImmutableList<Object> resolveToolsAndToolsets(
 
         throw new ConfigurationException("Tool or toolset not found: " + toolName);
 
-      } catch (Exception e) {
+      } catch (RuntimeException e) {
         String errorMsg = "Failed to resolve tool or toolset: " + toolConfig.name();
         logger.error(errorMsg, e);
         throw new ConfigurationException(errorMsg, e);
@@ -156,7 +156,7 @@ static ImmutableList<BaseTool> resolveTools(List<ToolConfig> toolConfigs, String
 
         throw new ConfigurationException("Tool not found: " + toolName);
 
-      } catch (Exception e) {
+      } catch (RuntimeException e) {
         String errorMsg = "Failed to resolve tool: " + toolConfig.name();
         logger.error(errorMsg, e);
         throw new ConfigurationException(errorMsg, e);
@@ -198,7 +198,7 @@ static BaseTool resolveToolInstance(String toolName) {
           logger.debug("Resolved and registered tool instance via reflection: {}", toolName);
           return tool;
         }
-      } catch (Exception e) {
+      } catch (ReflectiveOperationException | RuntimeException e) {
         logger.debug("Failed to resolve instance via reflection: {}", toolName, e);
       }
     }
@@ -237,7 +237,7 @@ static BaseToolset resolveToolsetInstance(String toolsetName) {
           logger.debug("Resolved and registered toolset instance via reflection: {}", toolsetName);
           return toolset;
         }
-      } catch (Exception e) {
+      } catch (ReflectiveOperationException | RuntimeException e) {
         logger.debug("Failed to resolve toolset instance via reflection: {}", toolsetName, e);
       }
     }
@@ -332,10 +332,11 @@ static BaseToolset resolveToolsetFromClass(
    *
    * @param toolsetName The toolset name in format "com.example.MyToolsetClass.INSTANCE".
    * @return The resolved toolset instance, or {@code null} if not found or not a BaseToolset.
-   * @throws Exception if the class cannot be loaded or field access fails.
+   * @throws ReflectiveOperationException if the class cannot be loaded or field access fails.
    */
   @Nullable
-  static BaseToolset resolveToolsetInstanceViaReflection(String toolsetName) throws Exception {
+  static BaseToolset resolveToolsetInstanceViaReflection(String toolsetName)
+      throws ReflectiveOperationException {
     int lastDotIndex = toolsetName.lastIndexOf('.');
     if (lastDotIndex == -1) {
       return null;
@@ -425,7 +426,7 @@ static BaseTool resolveToolFromClass(String className, ToolArgsConfig args, Stri
       } catch (NoSuchMethodException e) {
         throw new ConfigurationException(
             "Class " + className + " does not have fromConfig method but args were provided.", e);
-      } catch (Exception e) {
+      } catch (ReflectiveOperationException | RuntimeException e) {
         logger.error("Error calling fromConfig on class {}", className, e);
         throw new ConfigurationException("Error creating tool from class " + className, e);
       }
@@ -440,7 +441,7 @@ static BaseTool resolveToolFromClass(String className, ToolArgsConfig args, Stri
       throw new ConfigurationException(
           "Class " + className + " does not have a default constructor and no args were provided.",
           e);
-    } catch (Exception e) {
+    } catch (ReflectiveOperationException | RuntimeException e) {
       logger.error("Error calling default constructor on class {}", className, e);
       throw new ConfigurationException(
           "Error creating tool from class " + className + " using default constructor", e);
@@ -476,11 +477,12 @@ static boolean isJavaQualifiedName(String name) {
    * @param toolName The fully qualified name of a static field holding a tool instance.
    * @return The {@link BaseTool} instance, or {@code null} if {@code toolName} is not in the
    *     expected format, or if the field is not found, not static, or not of type {@link BaseTool}.
-   * @throws Exception if the class specified in {@code toolName} cannot be loaded, or if there is a
-   *     security manager preventing reflection, or if accessing the field causes an exception.
+   * @throws ReflectiveOperationException if the class specified in {@code toolName} cannot be
+   *     loaded, or if accessing the field causes an exception.
    */
   @Nullable
-  static BaseTool resolveInstanceViaReflection(String toolName) throws Exception {
+  static BaseTool resolveInstanceViaReflection(String toolName)
+      throws ReflectiveOperationException {
     int lastDotIndex = toolName.lastIndexOf('.');
     if (lastDotIndex == -1) {
       return null;

core/src/test/java/com/google/adk/agents/ToolResolverTest.java

@@ -291,7 +291,7 @@ public void testResolveTools_toolNotFound() {
             ConfigurationException.class,
             () -> ToolResolver.resolveTools(toolConfigs, "/test/path"));
 
-    assertThat(exception).hasMessageThat().contains("Failed to resolve tool: non.existent.Tool");
+    assertThat(exception).hasMessageThat().contains("Tool not found: non.existent.Tool");
   }
 
   /** A test tool with multiple methods annotated with @Schema. */

core/src/test/java/com/google/adk/testing/TestUtils.java

@@ -24,6 +24,7 @@
 import com.google.adk.agents.InvocationContext;
 import com.google.adk.agents.LlmAgent;
 import com.google.adk.agents.RunConfig;
+import com.google.adk.artifacts.InMemoryArtifactService;
 import com.google.adk.events.Event;
 import com.google.adk.events.EventActions;
 import com.google.adk.events.EventCompaction;
@@ -54,6 +55,7 @@ public static InvocationContext createInvocationContext(BaseAgent agent, RunConf
     InMemorySessionService sessionService = new InMemorySessionService();
     return InvocationContext.builder()
         .sessionService(sessionService)
+        .artifactService(new InMemoryArtifactService())
         .invocationId("invocationId")
         .agent(agent)
         .session(sessionService.createSession("test-app", "test-user").blockingGet())