Azure Blob初始化时出现java.lang.NoClassDefFoundError的解决方法

问题描述 #

初始化Azure Blob客户端时触发java.lang.NoClassDefFoundError: Could not initialize class com.azure.storage.blob.implementation.util.ModelHelper错误，初始化代码如下：

StorageSharedKeyCredential credential = new StorageSharedKeyCredential(ACCOUNT_NAME, ACCOUNT_KEY);
BlobServiceClient storageClient = new BlobServiceClientBuilder().endpoint(endpoint).credential(credential).buildClient();

错误日志 #

主错误日志 #

2022-10-28 12:03:30,802 ERROR org.apache.catalina.core.ContainerBase.[Tomcat].[localhost].[/].[dispatcherServlet] - Servlet.service() for servlet [dispatcherServlet] in context with path [] threw exception [Handler dispatch failed; nested exception is java.lang.NoClassDefFoundError: Could not initialize class com.azure.storage.blob.implementation.util.ModelHelper] with root cause
java.lang.NoClassDefFoundError: Could not initialize class com.azure.storage.blob.implementation.util.ModelHelper
        at com.azure.storage.blob.BlobUrlParts.parse(BlobUrlParts.java:371) ~[azure-storage-blob-12.20.0.jar!/:12.20.0]
        at com.azure.storage.blob.BlobServiceClientBuilder.endpoint(BlobServiceClientBuilder.java:171) ~[azure-storage-blob-12.20.0.jar!/:12.20.0]

关联错误日志 #

java.lang.ClassNotFoundException: com.fasterxml.jackson.databind.cfg.MapperBuilder
    at java.net.URLClassLoader.findClass(URLClassLoader.java:381) ~[?:1.8.0_111]
    at java.lang.ClassLoader.loadClass(ClassLoader.java:424) ~[?:1.8.0_111]
    at org.springframework.boot.loader.LaunchedURLClassLoader.loadClass(LaunchedURLClassLoader.java:94) ~[data-pipeline-automation-1.0.jar:0.0.1-SNAPSHOT]
    at java.lang.ClassLoader.loadClass(ClassLoader.java:357) ~[?:1.8.0_111]
    at com.azure.core.implementation.jackson.ObjectMapperShim.createHeaderMapper(ObjectMapperShim.java:135) ~[azure-core-1.33.0.jar!/:1.33.0]
    at com.azure.core.util.serializer.JacksonAdapter.<init>(JacksonAdapter.java:80) ~[azure-core-1.33.0.jar!/:1.33.0]
    at com.azure.core.util.serializer.JacksonAdapter.<init>(JacksonAdapter.java:58) ~[azure-core-1.33.0.jar!/:1.33.0]
    at com.azure.core.util.serializer.JacksonAdapter$SerializerAdapterHolder.<clinit>(JacksonAdapter.java:112) ~[azure-core-1.33.0.jar!/:1.33.0]
    at com.azure.core.util.serializer.JacksonAdapter.createDefaultSerializerAdapter(JacksonAdapter.java:121) ~[azure-core-1.33.0.jar!/:1.33.0]
    at com.azure.storage.blob.implementation.util.ModelHelper.<clinit>(ModelHelper.java:61) ~[azure-storage-blob-12.20.0.jar!/:12.20.0]
    at com.azure.storage.blob.BlobUrlParts.parse(BlobUrlParts.java:371) ~[azure-storage-blob-12.20.0.jar!/:12.20.0]
    at com.azure.storage.blob.BlobServiceClientBuilder.endpoint(BlobServiceClientBuilder.java:171) ~[azure-storage-blob-12.20.0.jar!/:12.20.0]

当前pom.xml依赖 #

<!-- https://mvnrepository.com/artifact/com.azure/azure-storage-blob -->
        <dependency>
            <groupId>com.azure</groupId>
            <artifactId>azure-storage-blob</artifactId>
            <version>12.20.0</version>
        </dependency>

        <!-- Needed to avoid java.lang.ClassNotFoundException-->
        <!-- https://mvnrepository.com/artifact/com.azure/azure-core -->
        <dependency>
            <groupId>com.azure</groupId>
            <artifactId>azure-core</artifactId>
            <version>1.33.0</version>
        </dependency>

解决方案 #

从关联错误日志可知，根源是缺少Jackson Databind依赖，com.fasterxml.jackson.databind.cfg.MapperBuilder类无法找到，而该类是Azure Core序列化功能的必需组件。按以下步骤修复：

1. 移除手动添加的azure-core依赖
   azure-storage-blob本身已依赖兼容版本的azure-core，手动指定版本可能引发依赖冲突或缺失传递依赖。

2. 添加Jackson Databind依赖
   在pom.xml中添加兼容版本的Jackson依赖：

<dependency>
    <groupId>com.fasterxml.jackson.core</groupId>
    <artifactId>jackson-databind</artifactId>
    <version>2.14.2</version> <!-- 推荐使用与azure-core 1.33.0匹配的版本，可通过mvn dependency:tree确认 -->
</dependency>

3. 清理重建项目
   执行mvn clean install，确保所有依赖正确下载并导入。

4. 检查依赖冲突
   运行mvn dependency:tree查看依赖树，排除任何与Jackson或azure-core冲突的依赖项。

优化方案：使用Azure BOM管理版本 #

为彻底避免版本兼容问题，可引入Azure SDK BOM统一管理所有Azure依赖版本：

<dependencyManagement>
    <dependencies>
        <dependency>
            <groupId>com.azure</groupId>
            <artifactId>azure-sdk-bom</artifactId>
            <version>2.30.0</version> <!-- 选择包含azure-storage-blob 12.20.0的BOM版本 -->
            <type>pom</type>
            <scope>import</scope>
        </dependency>
    </dependencies>
</dependencyManagement>

<!-- 无需指定版本，自动使用BOM中定义的兼容版本 -->
<dependency>
    <groupId>com.azure</groupId>
    <artifactId>azure-storage-blob</artifactId>
</dependency>

内容的提问来源于stack exchange，提问作者Deepak Gopal