SpringBoot 集成 LangChain4j 本地调用 Ollama

1 Ollama 软件下载

Ollama

2 Ollama 模型下载

2.1 PowerShell 下载脚本

复制内容到ollama_download.ps1文件中

# 定义模型名称避免硬编码
$modelName = "gemma3:27b"# 设置重试参数
$maxRetries = 50
$retryInterval = 3  # 秒
$downloadTimeout = 80  # 秒for ($retry = 1; $retry -le $maxRetries; $retry++) {# 精确检查模型是否存在$modelExists = ollama list | Where-Object { $_ -match "\b$modelName\b" }if ($modelExists) {Write-Host "[$(Get-Date)] model is already downloaded!"exit 0}Write-Host "[$(Get-Date)] start $retry times downloading..."# 启动进程并显示实时输出$process = Start-Process -FilePath "ollama" `-ArgumentList "run", $modelName `-PassThru `-NoNewWindow# 等待下载完成或超时try {$process | Wait-Process -Timeout $downloadTimeout -ErrorAction Stop} catch {# 超时处理Write-Host "download timeout, safe terminate process..."$process | Stop-Process -Force}if (-not $process.HasExited) {$process | Stop-Process -ForceWrite-Host "process terminated due to timeout."} else {# 检查退出代码if ($process.ExitCode -eq 0) {Write-Host "download success!"exit 0}Write-Host "download failed, exit code: $($process.ExitCode)"}Start-Sleep -Seconds $retryInterval
}Write-Host "exceeded maximum retries ($maxRetries), download failed."
exit 1

PS C:\Users\xuhya\Desktop> .\ollama_download.ps1
[10/09/2025 21:42:20] start 1 times downloading...
pulling manifest
pulling e796792eba26:  98% ▕████████████████████████████████████████████████████████  ▏  17 GB/ 17 GB  1.7 MB/s   3m20sdownload timeout, safe terminate process...
download failed, exit code: -1
[10/09/2025 21:43:43] start 2 times downloading...
pulling manifest
pulling e796792eba26: 100% ▕██████████████████████████████████████████████████████████▏  17 GB
pulling e0a42594d802: 100% ▕██████████████████████████████████████████████████████████▏  358 B
pulling dd084c7d92a3: 100% ▕██████████████████████████████████████████████████████████▏ 8.4 KB
pulling 3116c5225075: 100% ▕██████████████████████████████████████████████████████████▏   77 B
pulling f838f048d368: 100% ▕██████████████████████████████████████████████████████████▏  490 B
verifying sha256 digest ⠸ download timeout, safe terminate process...
download failed, exit code: -1
[10/09/2025 21:45:06] start 3 times downloading...
pulling manifest
pulling e796792eba26: 100% ▕██████████████████████████████████████████████████████████▏  17 GB
pulling e0a42594d802: 100% ▕██████████████████████████████████████████████████████████▏  358 B
pulling dd084c7d92a3: 100% ▕██████████████████████████████████████████████████████████▏ 8.4 KB
pulling 3116c5225075: 100% ▕██████████████████████████████████████████████████████████▏   77 B
pulling f838f048d368: 100% ▕██████████████████████████████████████████████████████████▏  490 B
verifying sha256 digest
writing manifest
success
⠏ download timeout, safe terminate process...
download failed, exit code: -1
[10/09/2025 21:46:29] model is already downloaded!
PS C:\Users\xuhya\Desktop>

2.2 Ollama模型运行

PS C:\Users\xuhya\Desktop> ollama list
NAME             ID              SIZE      MODIFIED
gemma3:27b       a418f5838eaf    17 GB     2 minutes ago
gemma3:latest    a2af6cc3eb7f    3.3 GB    7 minutes ago
PS C:\Users\xuhya\Desktop>

3 SpringBoot 集成 LangChain4j

3.1 pom依赖

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://maven.apache.org/POM/4.0.0"xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd"><modelVersion>4.0.0</modelVersion><parent><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-parent</artifactId><version>3.5.6</version><relativePath/> <!-- lookup parent from repository --></parent><groupId>com.xu</groupId><artifactId>lang-chain</artifactId><version>1.0.0</version><name>lang-chain</name><description>Demo project for Spring Boot</description><properties><java.version>25</java.version></properties><dependencyManagement><dependencies><dependency><groupId>dev.langchain4j</groupId><artifactId>langchain4j-bom</artifactId><version>1.6.0</version><type>pom</type><scope>import</scope></dependency></dependencies></dependencyManagement><dependencies><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-web</artifactId></dependency><dependency><groupId>dev.langchain4j</groupId><artifactId>langchain4j-spring-boot-starter</artifactId></dependency><dependency><groupId>dev.langchain4j</groupId><artifactId>langchain4j-open-ai-spring-boot-starter</artifactId></dependency><dependency><groupId>dev.langchain4j</groupId><artifactId>langchain4j-ollama</artifactId></dependency><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-devtools</artifactId><scope>runtime</scope><optional>true</optional></dependency><dependency><groupId>org.projectlombok</groupId><artifactId>lombok</artifactId><optional>true</optional></dependency><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-test</artifactId><scope>test</scope></dependency></dependencies><build><plugins><plugin><groupId>org.apache.maven.plugins</groupId><artifactId>maven-compiler-plugin</artifactId><configuration><annotationProcessorPaths><path><groupId>org.projectlombok</groupId><artifactId>lombok</artifactId></path></annotationProcessorPaths></configuration></plugin><plugin><groupId>org.springframework.boot</groupId><artifactId>spring-boot-maven-plugin</artifactId><configuration><excludes><exclude><groupId>org.projectlombok</groupId><artifactId>lombok</artifactId></exclude></excludes></configuration></plugin></plugins></build></project>

3.2 yml配置

server:port: 8080spring:application:name: lang-chainlogging:file:name: logs/spring-oracle.loglevel:root: INFOcom.xu: INFOlangchain4j:ollama:chat-model:base-url: http://127.0.0.1:11434model-name: gemma3:latest

3.3 bean配置

package com.xu.conf;import dev.langchain4j.http.client.spring.restclient.SpringRestClientBuilder;
import dev.langchain4j.memory.ChatMemory;
import dev.langchain4j.memory.chat.MessageWindowChatMemory;
import dev.langchain4j.model.ollama.OllamaChatModel;
import dev.langchain4j.model.ollama.OllamaStreamingChatModel;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;import java.time.Duration;@Configuration
public class OllamaConfig {@Value("${langchain4j.ollama.chat-model.model-name}")private String modelName;@Value("${langchain4j.ollama.chat-model.base-url}")private String baseUrl;@Beanpublic OllamaChatModel ollamaChatModel() {return OllamaChatModel.builder().modelName(modelName).baseUrl(baseUrl).httpClientBuilder(new SpringRestClientBuilder()).timeout(Duration.ofHours(10)) // 超时时间.maxRetries(3) // 超时最大重试次数.build();}@Beanpublic ChatMemory chatMemory() {return MessageWindowChatMemory.withMaxMessages(10); // 最多保存10条消息}@Beanpublic OllamaStreamingChatModel ollamaStreamingChatModel() {return OllamaStreamingChatModel.builder().modelName(modelName).baseUrl(baseUrl).httpClientBuilder(new SpringRestClientBuilder()).timeout(Duration.ofHours(10)) // 超时时间// 其他参数（可选）：温度值（0.0-1.0，越低越确定）.temperature(0.7).build();}}

3.4 无记忆

package com.xu.chat.controller;import dev.langchain4j.data.message.TextContent;
import dev.langchain4j.data.message.UserMessage;
import dev.langchain4j.model.chat.request.ChatRequest;
import dev.langchain4j.model.chat.response.ChatResponse;
import dev.langchain4j.model.ollama.OllamaChatModel;
import lombok.AllArgsConstructor;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RestController;@RestController
@AllArgsConstructor
@RequestMapping("/ollama")
public class OllamaController {private final OllamaChatModel ollama;@GetMapping("/model/chat")public Object chat(@RequestParam(value = "message", defaultValue = "你好") String message) {ChatRequest request = ChatRequest.builder().messages(UserMessage.userMessage(TextContent.from(message))).build();ChatResponse chat = ollama.chat(request);return chat.aiMessage().text();}}

3.5 有记忆

package com.xu.chat.controller;import dev.langchain4j.data.message.TextContent;
import dev.langchain4j.data.message.UserMessage;
import dev.langchain4j.memory.ChatMemory;
import dev.langchain4j.model.chat.request.ChatRequest;
import dev.langchain4j.model.chat.response.ChatResponse;
import dev.langchain4j.model.ollama.OllamaChatModel;
import lombok.AllArgsConstructor;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RestController;@RestController
@AllArgsConstructor
@RequestMapping("/ollama/memory")
public class MemoryController {private final OllamaChatModel ollama;private final ChatMemory chatMemory;@GetMapping("/model/chat")public Object chat(@RequestParam(value = "message", defaultValue = "你好") String message) {// 将用户消息添加到聊天历史UserMessage userMessage = UserMessage.userMessage(TextContent.from(message));chatMemory.add(userMessage);// 构建包含历史记录的请求ChatRequest request = ChatRequest.builder().messages(chatMemory.messages()).build();// 获取模型响应ChatResponse response = ollama.chat(request);var aiMessage = response.aiMessage();// 将 AI 响应也加入聊天历史chatMemory.add(aiMessage);return aiMessage;}}

5 SpringBoot 运行测试

  .   ____          _            __ _ _/\\ / ___'_ __ _ _(_)_ __  __ _ \ \ \ \
( ( )\___ | '_ | '_| | '_ \/ _` | \ \ \ \\\/  ___)| |_)| | | | | || (_| |  ) ) ) )'  |____| .__|_| |_|_| |_\__, | / / / /=========|_|==============|___/=/_/_/_/:: Spring Boot ::                (v3.5.6)2025-10-09T21:59:48.238+08:00  INFO 20840 --- [lang-chain] [  restartedMain] com.xu.LangChainApplication              : Starting LangChainApplication using Java 25 with PID 20840 (D:\SourceCode\Learn\lang-chain\target\classes started by xuhya in D:\SourceCode\Learn\lang-chain)
2025-10-09T21:59:48.241+08:00  INFO 20840 --- [lang-chain] [  restartedMain] com.xu.LangChainApplication              : No active profile set, falling back to 1 default profile: "default"
2025-10-09T21:59:48.317+08:00  INFO 20840 --- [lang-chain] [  restartedMain] .e.DevToolsPropertyDefaultsPostProcessor : Devtools property defaults active! Set 'spring.devtools.add-properties' to 'false' to disable
2025-10-09T21:59:48.317+08:00  INFO 20840 --- [lang-chain] [  restartedMain] .e.DevToolsPropertyDefaultsPostProcessor : For additional web related logging consider setting the 'logging.level.web' property to 'DEBUG'
2025-10-09T21:59:49.575+08:00  INFO 20840 --- [lang-chain] [  restartedMain] o.s.b.w.embedded.tomcat.TomcatWebServer  : Tomcat initialized with port 8080 (http)
2025-10-09T21:59:49.595+08:00  INFO 20840 --- [lang-chain] [  restartedMain] o.apache.catalina.core.StandardService   : Starting service [Tomcat]
2025-10-09T21:59:49.601+08:00  INFO 20840 --- [lang-chain] [  restartedMain] o.apache.catalina.core.StandardEngine    : Starting Servlet engine: [Apache Tomcat/10.1.46]
2025-10-09T21:59:49.649+08:00  INFO 20840 --- [lang-chain] [  restartedMain] o.a.c.c.C.[Tomcat].[localhost].[/]       : Initializing Spring embedded WebApplicationContext
2025-10-09T21:59:49.649+08:00  INFO 20840 --- [lang-chain] [  restartedMain] w.s.c.ServletWebServerApplicationContext : Root WebApplicationContext: initialization completed in 1331 ms
2025-10-09T21:59:50.163+08:00  INFO 20840 --- [lang-chain] [  restartedMain] o.s.b.d.a.OptionalLiveReloadServer       : LiveReload server is running on port 35729
2025-10-09T21:59:50.208+08:00  INFO 20840 --- [lang-chain] [  restartedMain] o.s.b.w.embedded.tomcat.TomcatWebServer  : Tomcat started on port 8080 (http) with context path '/'
2025-10-09T21:59:50.221+08:00  INFO 20840 --- [lang-chain] [  restartedMain] com.xu.LangChainApplication              : Started LangChainApplication in 2.791 seconds (process running for 3.655)