我正在嘗試在我的 Java 項目中使用 MongoDB。將我的項目導出到文件后，我收到 MongoClient 的無類定義錯誤。導出時我沒有收到任何錯誤。我使用 Maven 導入不同的依賴項，所有 jar 都被正確導出import com.mongodb.client.MongoClient;import com.mongodb.client.MongoClients;public class MongoDB { private static MongoClient client; public static void init() { try { client = MongoClients.create("mongodb://localhost:27017/xenoncraft"); System.out.println("[XenonSuite] Successfully connected to MongoDB"); } catch(Exception e) { System.out.println("[XenonSuite] Following errors were catched while connecting to MongoDB"); e.printStackTrace(); } }
2 回答
守著星空守著你
TA貢獻1799條經驗 獲得超8個贊
這就是我解決您的問題的方法：從Github 源代碼
檢出項目： 解壓縮、構建、測試 或 1. 創建了一個 maven 項目mvn archetype:generate -DarchetypeGroupId=org.apache.maven.archetypes -DarchetypeArtifactId=maven-archetype-quickstart -DarchetypeVersion=1.4
使用以下更新 pom.xml，從 OP 添加 mongo 客戶端代碼并打印集合名稱
執行
mvn clean packagejava -jar test.jar我得到的 執行 輸出是：
INFO: Opened connection [connectionId{localValue:1, serverValue:9}] to localhost:27017
Jun 01, 2019 8:17:22 PM com.mongodb.diagnostics.logging.JULLogger log
INFO: Monitor thread successfully connected to server with description ServerDescription{address=localhost:27017, type=STANDALONE, state=CONNECTED, ok=true, version=ServerVersion{versionList=[4, 0, 5]}, minWireVersion=0, maxWireVersion=7, maxDocumentSize=16777216, logicalSessionTimeoutMinutes=30, roundTripTimeNanos=2249770}
Jun 01, 2019 8:17:22 PM com.mongodb.diagnostics.logging.JULLogger log
INFO: Opened connection [connectionId{localValue:2, serverValue:10}] to localhost:27017
admin
config
local
test
[XenonSuite] Successfully connected to MongoDB
pom.xml（忽略包名稱）
檢查陰影插件配置
<?xml version="1.0" encoding="UTF-8"?>
<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>
<groupId>test</groupId>
<artifactId>test</artifactId>
<version>1.0-SNAPSHOT</version>
<name>test</name>
<!-- FIXME change it to the project's website -->
<url>http://www.example.com</url>
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<maven.compiler.source>1.8</maven.compiler.source>
<maven.compiler.target>1.8</maven.compiler.target>
<mainClass>test.App</mainClass>
</properties>
<packaging>jar</packaging>
<dependencies>
<!-- https://mvnrepository.com/artifact/org.mongodb/mongo-java-driver -->
<dependency>
<groupId>org.mongodb</groupId>
<artifactId>mongo-java-driver</artifactId>
<version>3.10.2</version>
</dependency>
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>4.11</version>
<scope>test</scope>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-assembly-plugin</artifactId>
<version>3.1.1</version>
</plugin>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-dependency-plugin</artifactId>
<version>3.1.1</version>
</plugin>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-jar-plugin</artifactId>
<version>3.1.1</version>
</plugin>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-shade-plugin</artifactId>
<version>3.2.1</version>
<executions>
<execution>
<phase>package</phase>
<goals>
<goal>shade</goal>
</goals>
<configuration>
<shadedArtifactAttached>true</shadedArtifactAttached>
<transformers>
<transformer implementation="org.apache.maven.plugins.shade.resource.ManifestResourceTransformer">
<mainClass>test.App</mainClass>
</transformer>
</transformers>
<finalName>test</finalName>
</configuration>
</execution>
</executions>
</plugin>
</plugins>
</build>
</project>
有多種方法可以解決這個問題 Ref: https://www.baeldung.com/executable-jar-with-maven
慕運維8079593
TA貢獻1876條經驗 獲得超5個贊
確保您在 Maven pom.xml 中具有以下依賴項。
org.mongodb mongodb 驅動程序 3.9.1
如果你不使用 maven，你必須從 mvnrepository.com 下載這個 jar 文件，你還必須下載 bson.jar，版本為 3.9.1 的 mongodb-driver-core，你必須下載 slf4j-api.jar版本 1.7.6。
添加回答
舉報
0/150
提交
取消