feat(i18n): Enhance i18n support with configurable resource bundle base name

Author: codeboyzhou

src/main/java/com/github/codeboyzhou/mcp/declarative/annotation/McpI18nEnabled.java

@@ -18,7 +18,7 @@
  * <p>Example usage:
  *
  * <pre>{@code
- * @McpI18nEnabled
+ * @McpI18nEnabled(resourceBundleBaseName = "mcp_server_component_i18n")
  * public class MyMcpServerApplication {
  *     // Application logic...
  * }
@@ -28,4 +28,16 @@
  */
 @Target(ElementType.TYPE)
 @Retention(RetentionPolicy.RUNTIME)
-public @interface McpI18nEnabled {}
+public @interface McpI18nEnabled {
+  /**
+   * Specifies the base name of the resource bundle to be used for i18n.
+   *
+   * <p>The resource bundle base name should follow the standard Java resource bundle naming
+   * convention. For example, if the resource bundle base name is "messages", the corresponding
+   * resource bundle files should be named "messages.properties", "messages_en_US.properties",
+   * "messages_zh_CN.properties", etc.
+   *
+   * @return the base name of the resource bundle
+   */
+  String resourceBundleBaseName();
+}

src/main/java/com/github/codeboyzhou/mcp/declarative/di/GuiceInjectorModule.java

@@ -18,14 +18,18 @@
 import com.github.codeboyzhou.mcp.declarative.server.component.McpServerTool;
 import com.github.codeboyzhou.mcp.declarative.server.converter.McpPromptParameterConverter;
 import com.github.codeboyzhou.mcp.declarative.server.converter.McpToolParameterConverter;
+import com.github.codeboyzhou.mcp.declarative.util.StringHelper;
 import com.google.inject.AbstractModule;
 import com.google.inject.Provides;
 import com.google.inject.Singleton;
-import com.google.inject.name.Names;
 import java.lang.annotation.Annotation;
 import java.lang.reflect.Method;
+import java.util.Locale;
+import java.util.ResourceBundle;
 import java.util.Set;
 import org.reflections.Reflections;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 /**
  * This class is a Guice module that configures bindings for classes annotated with {@link
@@ -35,8 +39,7 @@
  */
 public final class GuiceInjectorModule extends AbstractModule {
 
-  /** The name of the injected variable for i18n enabled. */
-  public static final String INJECTED_VARIABLE_NAME_I18N_ENABLED = "i18nEnabled";
+  private static final Logger log = LoggerFactory.getLogger(GuiceInjectorModule.class);
 
   /** The main class to use for configuration. */
   private final Class<?> mainClass;
@@ -70,12 +73,6 @@ protected void configure() {
     bind(McpStdioServer.class).in(SINGLETON);
     bind(McpSseServer.class).in(SINGLETON);
     bind(McpStreamableServer.class).in(SINGLETON);
-
-    // Bind for boolean variable: i18nEnabled
-    final boolean i18nEnabled = mainClass.isAnnotationPresent(McpI18nEnabled.class);
-    bind(Boolean.class)
-        .annotatedWith(Names.named(INJECTED_VARIABLE_NAME_I18N_ENABLED))
-        .toInstance(i18nEnabled);
   }
 
   /**
@@ -91,6 +88,28 @@ public Reflections provideReflections() {
     return new Reflections(basePackage, MethodsAnnotated, FieldsAnnotated);
   }
 
+  /**
+   * Provides a {@link ResourceBundle} instance for the main class.
+   *
+   * @return a {@link ResourceBundle} instance for the main class
+   */
+  @Provides
+  @Singleton
+  public ResourceBundle provideResourceBundle() {
+    McpI18nEnabled mcpI18nEnabled = mainClass.getAnnotation(McpI18nEnabled.class);
+    if (mcpI18nEnabled == null) {
+      log.info("McpI18nEnabled annotation is not present on the main class, skip i18n support.");
+      return null;
+    }
+
+    final String baseName = mcpI18nEnabled.resourceBundleBaseName();
+    if (StringHelper.isBlank(baseName)) {
+      throw new IllegalArgumentException("resourceBundleBaseName must not be blank.");
+    }
+
+    return ResourceBundle.getBundle(baseName, Locale.getDefault());
+  }
+
   /**
    * Determines the base package for the {@link Reflections} instance to scan.
    *

src/main/java/com/github/codeboyzhou/mcp/declarative/server/component/AbstractMcpServerComponent.java

@@ -1,14 +1,9 @@
 package com.github.codeboyzhou.mcp.declarative.server.component;
 
-import static com.github.codeboyzhou.mcp.declarative.di.GuiceInjectorModule.INJECTED_VARIABLE_NAME_I18N_ENABLED;
-
 import com.github.codeboyzhou.mcp.declarative.di.DependencyInjector;
 import com.github.codeboyzhou.mcp.declarative.di.DependencyInjectorProvider;
 import com.github.codeboyzhou.mcp.declarative.util.StringHelper;
-import java.util.Locale;
 import java.util.ResourceBundle;
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
 
 /**
  * This abstract class represents an MCP server component (resource/prompt/tool) that is responsible
@@ -19,12 +14,6 @@
  * @author codeboyzhou
  */
 public abstract class AbstractMcpServerComponent<T> implements McpServerComponent<T> {
-
-  private static final Logger log = LoggerFactory.getLogger(AbstractMcpServerComponent.class);
-
-  /** The base name of the resource bundle for MCP server component descriptions. */
-  private static final String RESOURCE_BUNDLE_BASE_NAME = "i18n/mcp_server_component_descriptions";
-
   /** The default value to use when a component attribute is not specified. */
   protected static final String NOT_SPECIFIED = "Not specified";
 
@@ -34,14 +23,10 @@ public abstract class AbstractMcpServerComponent<T> implements McpServerComponen
   /** The resource bundle to use for localizing component descriptions. */
   private final ResourceBundle bundle;
 
-  /** Whether to enable i18n for component descriptions. */
-  private final boolean i18nEnabled;
-
   /** Creates a new instance of {@code AbstractMcpServerComponent}. */
   protected AbstractMcpServerComponent() {
-    this.bundle = loadResourceBundle();
     this.injector = DependencyInjectorProvider.INSTANCE.getInjector();
-    this.i18nEnabled = injector.getVariable(Boolean.class, INJECTED_VARIABLE_NAME_I18N_ENABLED);
+    this.bundle = injector.getInstance(ResourceBundle.class);
   }
 
   /**
@@ -52,27 +37,9 @@ protected AbstractMcpServerComponent() {
    * @return the resolved value of the component attribute
    */
   protected String resolveComponentAttributeValue(String attributeLiteralValue) {
-    if (i18nEnabled && bundle != null && bundle.containsKey(attributeLiteralValue)) {
+    if (bundle != null && bundle.containsKey(attributeLiteralValue)) {
       return bundle.getString(attributeLiteralValue);
     }
     return StringHelper.defaultIfBlank(attributeLiteralValue, NOT_SPECIFIED);
   }
-
-  /**
-   * Loads the resource bundle for MCP server component descriptions, using the default locale.
-   *
-   * @return the resource bundle for MCP server component descriptions
-   */
-  private ResourceBundle loadResourceBundle() {
-    Locale locale = Locale.getDefault();
-    try {
-      return ResourceBundle.getBundle(RESOURCE_BUNDLE_BASE_NAME, locale);
-    } catch (Exception e) {
-      log.warn(
-          "Can't find resource bundle for base name: {}, locale {}, i18n will be unsupported",
-          RESOURCE_BUNDLE_BASE_NAME,
-          locale);
-      return null;
-    }
-  }
 }

src/main/java/com/github/codeboyzhou/mcp/declarative/util/StringHelper.java

@@ -28,6 +28,16 @@ public final class StringHelper {
     throw new UnsupportedOperationException("Utility class should not be instantiated");
   }
 
+  /**
+   * Checks if the given string is blank.
+   *
+   * @param str the string to check
+   * @return {@code true} if the string is blank, {@code false} otherwise
+   */
+  public static boolean isBlank(String str) {
+    return str == null || str.isBlank();
+  }
+
   /**
    * Returns the default value if the given string is blank, otherwise returns the original string.
    *