[aipp-plugin] refactor: replace MCP client with LangChain4j MCP module

app-builder/plugins/aipp-plugin/pom.xml

@@ -134,8 +134,8 @@
             <artifactId>waterflow-graph-service</artifactId>
         </dependency>
         <dependency>
-            <groupId>org.fitframework.fel</groupId>
-            <artifactId>tool-mcp-client-service</artifactId>
+            <groupId>dev.langchain4j</groupId>
+            <artifactId>langchain4j-mcp</artifactId>
         </dependency>
 
         <!-- Redis -->

app-builder/plugins/aipp-plugin/src/main/java/modelengine/fit/jober/aipp/fel/FelComponentConfig.java

@@ -9,9 +9,9 @@
 import modelengine.fel.core.chat.ChatModel;
 import modelengine.fel.core.chat.Prompt;
 import modelengine.fel.engine.operators.patterns.AbstractAgent;
-import modelengine.fel.tool.mcp.client.McpClientFactory;
 import modelengine.fel.tool.service.ToolExecuteService;
 import modelengine.fit.jober.aipp.constants.AippConst;
+import modelengine.fit.jober.aipp.util.McpClientFactory;
 import modelengine.fitframework.annotation.Bean;
 import modelengine.fitframework.annotation.Component;
 import modelengine.fitframework.annotation.Fit;
@@ -29,12 +29,13 @@ public class FelComponentConfig {
      *
      * @param toolExecuteService 表示工具调用服务的 {@link ToolExecuteService}。
      * @param chatModel 表示模型流式服务的 {@link ChatModel}。
-     * @param mcpClientFactory 表示大模型上下文客户端工厂的 {@link McpClientFactory}。
+     * @param mcpClientFactory 表示 MCP 客户端工厂的 {@link McpClientFactory}。
      * @return 返回 WaterFlow 场景的 Agent 服务的 {@link AbstractAgent}{@code <}{@link Prompt}{@code ,
      * }{@link Prompt}{@code >}。
      */
     @Bean(AippConst.WATER_FLOW_AGENT_BEAN)
-    public AbstractAgent getWaterFlowAgent(@Fit ToolExecuteService toolExecuteService, ChatModel chatModel, McpClientFactory mcpClientFactory) {
+    public AbstractAgent getWaterFlowAgent(@Fit ToolExecuteService toolExecuteService, ChatModel chatModel,
+            McpClientFactory mcpClientFactory) {
         return new WaterFlowAgent(toolExecuteService, chatModel, mcpClientFactory);
     }
 }

app-builder/plugins/aipp-plugin/src/main/java/modelengine/fit/jober/aipp/fel/WaterFlowAgent.java

@@ -6,9 +6,6 @@
 
 package modelengine.fit.jober.aipp.fel;
 
-import com.alibaba.fastjson.JSON;
-import com.alibaba.fastjson.JSONObject;
-
 import modelengine.fel.core.chat.ChatMessage;
 import modelengine.fel.core.chat.ChatModel;
 import modelengine.fel.core.chat.Prompt;
@@ -22,20 +19,20 @@
 import modelengine.fel.engine.operators.models.ChatChunk;
 import modelengine.fel.engine.operators.models.ChatFlowModel;
 import modelengine.fel.engine.operators.patterns.AbstractAgent;
-import modelengine.fel.tool.mcp.client.McpClient;
-import modelengine.fel.tool.mcp.client.McpClientFactory;
 import modelengine.fel.tool.service.ToolExecuteService;
 import modelengine.fit.jober.aipp.common.exception.AippErrCode;
 import modelengine.fit.jober.aipp.common.exception.AippException;
 import modelengine.fit.jober.aipp.constants.AippConst;
+import modelengine.fit.jober.aipp.util.LangChain4jMcpClient;
+import modelengine.fit.jober.aipp.util.McpClientFactory;
 import modelengine.fit.jober.aipp.util.McpUtils;
 import modelengine.fit.waterflow.domain.context.StateContext;
 import modelengine.fitframework.annotation.Fit;
 import modelengine.fitframework.inspection.Validation;
+import modelengine.fitframework.log.Logger;
 import modelengine.fitframework.util.CollectionUtils;
 import modelengine.fitframework.util.ObjectUtils;
 
-import java.io.IOException;
 import java.util.Collections;
 import java.util.List;
 import java.util.Map;
@@ -61,14 +58,14 @@ public class WaterFlowAgent extends AbstractAgent {
      *
      * @param toolExecuteService 表示工具调用服务的 {@link ToolExecuteService}。
      * @param chatStreamModel 表示流式对话大模型的 {@link ChatModel}。
-     * @param mcpClientFactory 表示大模型上下文客户端工厂的 {@link McpClientFactory}。
+     * @param mcpClientFactory 表示 MCP 客户端工厂的 {@link McpClientFactory}。
      */
     public WaterFlowAgent(@Fit ToolExecuteService toolExecuteService, ChatModel chatStreamModel,
             McpClientFactory mcpClientFactory) {
         super(new ChatFlowModel(chatStreamModel, null));
         this.toolExecuteService = Validation.notNull(toolExecuteService, "The tool execute service cannot be null.");
-        this.mcpClientFactory = Validation.notNull(mcpClientFactory, "The mcp client factory cannot be null.");
         this.agentMsgKey = AGENT_MSG_KEY;
+        this.mcpClientFactory = mcpClientFactory;
     }
 
     @Override
@@ -136,12 +133,10 @@ private ChatMessage callTool(ToolCall toolCall, Map<String, ToolInfo> toolsMap,
         if (mcpServerConfig != null) {
             String url = Validation.notBlank(ObjectUtils.cast(mcpServerConfig.get(AippConst.MCP_SERVER_URL_KEY)),
                     "The mcp url should not be empty.");
-            try (McpClient mcpClient = this.mcpClientFactory.create(McpUtils.getBaseUrl(url),
-                    McpUtils.getSseEndpoint(url))) {
-                mcpClient.initialize();
-                Object result = mcpClient.callTool(toolRealName, JSONObject.parseObject(toolCall.arguments()));
-                return new ToolMessage(toolCall.id(), JSON.toJSONString(result));
-            } catch (IOException exception) {
+            try (LangChain4jMcpClient mcpClient = this.mcpClientFactory.create(url)) {
+                String result = mcpClient.callTool(toolRealName, toolCall.arguments());
+                return new ToolMessage(toolCall.id(), result);
+            } catch (Exception exception) {
                 throw new AippException(AippErrCode.CALL_MCP_SERVER_FAILED, exception.getMessage());
             }
         }

app-builder/plugins/aipp-plugin/src/main/java/modelengine/fit/jober/aipp/fitable/LlmComponent.java

@@ -20,13 +20,11 @@
 import modelengine.fel.engine.flows.AiProcessFlow;
 import modelengine.fel.engine.operators.patterns.AbstractAgent;
 import modelengine.fel.engine.operators.prompts.Prompts;
-import modelengine.fel.tool.mcp.client.McpClient;
-import modelengine.fel.tool.mcp.client.McpClientFactory;
-import modelengine.fel.tool.mcp.entity.Tool;
 import modelengine.fel.tool.model.transfer.ToolData;
 import modelengine.fit.jober.aipp.domains.appversion.service.AppVersionService;
 import modelengine.fit.jober.aipp.enums.MetaInstStatusEnum;
-import modelengine.fit.jober.aipp.util.McpUtils;
+import modelengine.fit.jober.aipp.util.LangChain4jMcpClient;
+import modelengine.fit.jober.aipp.util.McpClientFactory;
 import modelengine.fitframework.inspection.Validation;
 import modelengine.jade.store.service.ToolService;
 import modelengine.fit.jade.aipp.formatter.OutputFormatterChain;
@@ -70,6 +68,9 @@
 import modelengine.fitframework.util.StringUtils;
 import modelengine.fitframework.util.UuidUtils;
 
+import dev.langchain4j.model.chat.request.json.JsonObjectSchema;
+import dev.langchain4j.agent.tool.ToolSpecification;
+
 import java.io.IOException;
 import java.util.ArrayList;
 import java.util.Collections;
@@ -113,9 +114,9 @@ public class LlmComponent implements FlowableService {
     private final AippModelCenter aippModelCenter;
     private final PromptBuilderChain promptBuilderChain;
     private final AppTaskInstanceService appTaskInstanceService;
-    private final McpClientFactory mcpClientFactory;
     private final OutputFormatterChain formatterChain;
     private final AppVersionService appVersionService;
+    private final McpClientFactory mcpClientFactory;
 
     /**
      * 大模型节点构造器，内部通过提供的 agent 和 tool 构建智能体工作流。
@@ -129,7 +130,9 @@ public class LlmComponent implements FlowableService {
      * @param aippModelCenter 表示模型中心的 {@link AippModelCenter}。
      * @param promptBuilderChain 表示提示器构造器职责链的 {@link PromptBuilderChain}。
      * @param appTaskInstanceService 表示任务实例服务的 {@link AppTaskInstanceService}。
-     * @param mcpClientFactory 表示大模型上下文客户端工厂的 {@link McpClientFactory}。
+     * @param formatterChain 表示输出格式化器链的 {@link OutputFormatterChain}。
+     * @param appVersionService 表示应用版本服务的 {@link AppVersionService}。
+     * @param mcpClientFactory 表示 MCP 客户端工厂的 {@link McpClientFactory}。
      */
     public LlmComponent(FlowInstanceService flowInstanceService,
             @Fit ToolService toolService,
@@ -141,13 +144,15 @@ public LlmComponent(FlowInstanceService flowInstanceService,
             PromptBuilderChain promptBuilderChain,
             AppTaskInstanceService appTaskInstanceService,
             OutputFormatterChain formatterChain,
-            McpClientFactory mcpClientFactory, AppVersionService appVersionService) {
+            AppVersionService appVersionService,
+            McpClientFactory mcpClientFactory) {
         this.flowInstanceService = flowInstanceService;
         this.toolService = toolService;
         this.aippLogService = aippLogService;
         this.aippLogStreamService = aippLogStreamService;
         this.serializer = notNull(serializer, "The serializer cannot be nul.");
         this.aippModelCenter = aippModelCenter;
+        this.mcpClientFactory = mcpClientFactory;
 
         // handleTask从入口开始处理，callback从agent node开始处理
         this.agentFlow = AiFlows.<Tip>create()
@@ -157,7 +162,6 @@ public LlmComponent(FlowInstanceService flowInstanceService,
                 .close();
         this.promptBuilderChain = promptBuilderChain;
         this.appTaskInstanceService = appTaskInstanceService;
-        this.mcpClientFactory = notNull(mcpClientFactory, "The mcp client factory cannot be null.");
         this.formatterChain = formatterChain;
         this.appVersionService = appVersionService;
     }
@@ -482,12 +486,12 @@ private List<ToolInfo> buildMcpToolInfos(Map<String, Object> mcpServersConfig) {
             String url = Validation.notBlank(ObjectUtils.cast(serverConfig.get(AippConst.MCP_SERVER_URL_KEY)),
                     "The mcp url should not be empty.");
 
-            try (McpClient mcpClient = this.mcpClientFactory.create(McpUtils.getBaseUrl(url),
-                    McpUtils.getSseEndpoint(url))) {
-                mcpClient.initialize();
-                List<Tool> tools = mcpClient.getTools();
-                result.addAll(tools.stream().map(tool -> buildMcpToolInfo(serverName, tool, serverConfig)).toList());
-            } catch (IOException exception) {
+            try (LangChain4jMcpClient mcpClient = this.mcpClientFactory.create(url)) {
+                List<ToolSpecification> tools = mcpClient.getTools();
+                result.addAll(tools.stream()
+                        .map(tool -> buildMcpToolInfo(serverName, tool, serverConfig))
+                        .toList());
+            } catch (Exception exception) {
                 throw new AippException(AippErrCode.CALL_MCP_SERVER_FAILED, exception.getMessage());
             }
         });
@@ -515,14 +519,23 @@ private ToolInfo buildToolInfo(ToolData toolData) {
                 .build();
     }
 
-    private static ToolInfo buildMcpToolInfo(String serverName, Tool tool, Map<String, Object> serverConfig) {
+    private static ToolInfo buildMcpToolInfo(String serverName, 
+            ToolSpecification tool, Map<String, Object> serverConfig) {
+        JsonObjectSchema toolParams = tool.parameters();
+        Map<String, Object> parametersMap = new HashMap<>();
+        if (toolParams != null) {
+            parametersMap.put("type", "object");
+            parametersMap.put("properties", toolParams.properties());
+            parametersMap.put("required", toolParams.required());
+        }
+
         return ToolInfo.custom()
-                .name(buildUniqueToolName(AippConst.MCP_SERVER_TYPE, serverName, tool.getName()))
-                .description(tool.getDescription())
-                .parameters(tool.getInputSchema())
+                .name(buildUniqueToolName(AippConst.MCP_SERVER_TYPE, serverName, tool.name()))
+                .description(tool.description())
+                .parameters(parametersMap)
                 .extensions(MapBuilder.<String, Object>get()
                         .put(AippConst.MCP_SERVER_KEY, serverConfig)
-                        .put(AippConst.TOOL_REAL_NAME, tool.getName())
+                        .put(AippConst.TOOL_REAL_NAME, tool.name())
                         .build())
                 .build();
     }

app-builder/plugins/aipp-plugin/src/main/java/modelengine/fit/jober/aipp/util/DefaultMcpClientFactory.java

@@ -0,0 +1,23 @@
+/*---------------------------------------------------------------------------------------------
+ *  Copyright (c) 2025 Huawei Technologies Co., Ltd. All rights reserved.
+ *  This file is a part of the ModelEngine Project.
+ *  Licensed under the MIT License. See License.txt in the project root for license information.
+ *--------------------------------------------------------------------------------------------*/
+
+package modelengine.fit.jober.aipp.util;
+
+import modelengine.fitframework.annotation.Component;
+
+/**
+ * MCP 客户端工厂的默认实现，使用 {@link LangChain4jMcpClient} 创建客户端实例。
+ *
+ * @author songyongtan
+ * @since 2026-03-02
+ */
+@Component
+public class DefaultMcpClientFactory implements McpClientFactory {
+    @Override
+    public LangChain4jMcpClient create(String url) {
+        return new LangChain4jMcpClient(url);
+    }
+}

app-builder/plugins/aipp-plugin/src/main/java/modelengine/fit/jober/aipp/util/LangChain4jMcpClient.java

@@ -0,0 +1,92 @@
+/*---------------------------------------------------------------------------------------------
+ *  Copyright (c) 2025 Huawei Technologies Co., Ltd. All rights reserved.
+ *  This file is a part of the ModelEngine Project.
+ *  Licensed under the MIT License. See License.txt in the project root for license information.
+ *--------------------------------------------------------------------------------------------*/
+
+
+package modelengine.fit.jober.aipp.util;
+
+import dev.langchain4j.agent.tool.ToolExecutionRequest;
+import dev.langchain4j.agent.tool.ToolSpecification;
+import dev.langchain4j.mcp.client.DefaultMcpClient;
+import dev.langchain4j.mcp.client.McpClient;
+import dev.langchain4j.mcp.client.transport.http.HttpMcpTransport;
+
+import modelengine.fit.jober.aipp.common.exception.AippErrCode;
+import modelengine.fit.jober.aipp.common.exception.AippException;
+import modelengine.fitframework.util.StringUtils;
+
+import java.util.List;
+
+/**
+ * LangChain4jMcpClient is a client for calling ModelEngine's MCP server.
+ * 
+ * @author songyongtan
+ * @since 2026-03-01
+ */
+public class LangChain4jMcpClient implements AutoCloseable {
+    private final McpClient mcpClient;
+    private final String url;
+
+    /**
+     * 构造函数，用于初始化LangChain4jMcpClient对象。
+     *
+     * @param url MCP服务器的URL，格式为http://host:port
+     */
+    public LangChain4jMcpClient(String url) {
+        this.url = url;
+
+        HttpMcpTransport transport = new HttpMcpTransport.Builder()
+                .sseUrl(url)
+                .build();
+
+        this.mcpClient = new DefaultMcpClient.Builder()
+                .transport(transport)
+                .build();
+    }
+
+    /**
+     * 获取MCP服务器上注册的所有工具。
+     *
+     * @return 包含所有工具规范的列表
+     */
+    public List<ToolSpecification> getTools() {
+        try {
+            return this.mcpClient.listTools();
+        } catch (Exception e) {
+            throw new AippException(AippErrCode.CALL_MCP_SERVER_FAILED, 
+                    StringUtils.format("Failed to get tools from MCP server. [url={0}]", this.url), e);
+        }
+    }
+
+    /**
+     * 调用MCP服务器上的指定工具。
+     *
+     * @param toolName 要调用的工具名称
+     * @param arguments 工具调用的参数，格式为JSON字符串
+     * @return 工具调用的结果，格式为JSON字符串
+     */
+    public String callTool(String toolName, String arguments) {
+        try {
+            ToolExecutionRequest request = ToolExecutionRequest.builder()
+                    .name(toolName)
+                    .arguments(arguments)
+                    .build();
+            return mcpClient.executeTool(request).resultText();
+        } catch (Exception e) {
+            throw new AippException(AippErrCode.CALL_MCP_SERVER_FAILED, 
+                    StringUtils.format("Failed to call tool. [toolName={0}, url={1}]", toolName, this.url), e);
+        }
+    }
+
+    @Override
+    public void close() {
+        try {
+            this.mcpClient.close();
+        } catch (Exception e) {
+            throw new AippException(AippErrCode.CALL_MCP_SERVER_FAILED, 
+                    StringUtils.format("Failed to close MCP client. [url={0}]", this.url), e);
+        }
+    }
+}

app-builder/plugins/aipp-plugin/src/main/java/modelengine/fit/jober/aipp/util/McpClientFactory.java

@@ -0,0 +1,23 @@
+/*---------------------------------------------------------------------------------------------
+ *  Copyright (c) 2025 Huawei Technologies Co., Ltd. All rights reserved.
+ *  This file is a part of the ModelEngine Project.
+ *  Licensed under the MIT License. See License.txt in the project root for license information.
+ *--------------------------------------------------------------------------------------------*/
+
+package modelengine.fit.jober.aipp.util;
+
+/**
+ * MCP 客户端工厂接口，用于创建 {@link LangChain4jMcpClient} 实例。
+ *
+ * @author songyongtan
+ * @since 2026-03-02
+ */
+public interface McpClientFactory {
+    /**
+     * 创建 MCP 客户端实例。
+     *
+     * @param url 表示 MCP 服务器的 URL。
+     * @return 返回创建的 {@link LangChain4jMcpClient} 实例。
+     */
+    LangChain4jMcpClient create(String url);
+}