【Azure Developer】VS Code运行Java 版Azure Storage SDK操作Blob (新建Container, 上传Blob文件

VS Code运行Java 版Azure Storage SDK操作Blob (新建Container, 上传Blob文件，下载及清理)

问题描述

是否可以用Java代码来管理Azure blob？ 可以。在代码中加入azure-storage-blob依赖。即可使用以下类操作Azure Storage Blob。

• BlobServiceClient：BlobServiceClient 类可用于操纵 Azure 存储资源和 blob 容器。 存储帐户为 Blob 服务提供顶级命名空间。
• BlobServiceClientBuilder：BlobServiceClientBuilder 类提供流畅的生成器 API，以帮助对 BlobServiceClient 对象的配置和实例化。
• BlobContainerClient：BlobContainerClient 类可用于操纵 Azure 存储容器及其 blob。
• BlobClient：BlobClient 类可用于操纵 Azure 存储 blob。
• BlobItem：BlobItem 类表示从对 listBlobs 的调用返回的单个 blob。

执行步骤

首先，设置VS Code上执行Java 代码的环境，这里需要的步骤比较多。完全参考VS Code for Java文档即可：​​https://code.visualstudio.com/docs/java/java-tutorial​​. 

以下是创建项目步骤：

1）创建blob-quickstart-v12项目

跳转到blob-quickstart-v12目录，并在目录中创建一个data目录，用于在接下来的代码中创建本地文件及下载bolb中的文件

cd blob-quickstart-v12

mkdir data

2)   修改pom.xml，添加对Java azure-storage-blob SDK的依赖

<dependencies>
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>4.11</version>
<scope>test</scope>
</dependency>
<dependency>
<groupId>com.azure</groupId>
<artifactId>azure-storage-blob</artifactId>
<version>12.6.0</version>
</dependency>
</dependencies>

3）在App.java代码文件中添加引用

package com.blobs.quickstart;

/**
* Azure blob storage v12 SDK quickstart
*/
import com.azure.storage.blob.*;
import com.azure.storage.blob.models.*;
import java.io.*;

public class App
{
public static void main( String[] args ) throws IOException
{
System.out.println("Azure Blob storage v12 - Java quickstart sample\n");

 

4）添加Stroage Account的连接字符串

 

 

 

5）创建blobServiceClient对象，同时调用createBlobContainer方法创建容器

// Create a BlobServiceClient object which will be used to create a container client
BlobServiceClient blobServiceClient = new BlobServiceClientBuilder().connectionString(connectStr).buildClient();

//Create a unique name for the container
String containerName = "quickstartblobs" + java.util.UUID.randomUUID();

// Create the container and return a container client object

6）创建BlobClient对象，同时调用uploadFromFile方法上传文件(.tx)

// Create a local file in the ./data/ directory for uploading and downloading
String localPath = "./data/";
String fileName = "quickstart" + java.util.UUID.randomUUID() + ".txt";
File localFile = new File(localPath + fileName);

// Write text to the file
FileWriter writer = new FileWriter(localPath + fileName, true);
writer.write("Hello, World!");
writer.close();

// Get a reference to a blob
BlobClient blobClient = containerClient.getBlobClient(fileName);

System.out.println("\nUploading to Blob storage as blob:\n\t" + blobClient.getBlobUrl());

// Upload the blob

 

7）使用containerClient对象的listBlobs方法列出容器中的BlobItem

);

// List the blob(s) in the container.
for (BlobItem blobItem : containerClient.listBlobs()) {
System.out.println("\t" + blobItem.getName());
}

 

8）使用blobClient对象的downloadToFile方法下载文件到本地

// Download the blob to a local file
// Append the string "DOWNLOAD" before the .txt extension so that you can see both files.
String downloadFileName = fileName.replace(".txt", "DOWNLOAD.txt");
File downloadedFile = new File(localPath + downloadFileName);

System.out.println("\nDownloading blob to\n\t " + localPath + downloadFileName);

blobClient.downloadToFile(localPath + downloadFileName);

 

9）使用containerClient对象的delete方法删除容器

// Clean up
System.out.println("\nPress the Enter key to begin clean up");
System.console().readLine();

System.out.println("Deleting blob container...");
containerClient.delete();

System.out.println("Deleting the local source and downloaded files...");
localFile.delete();
downloadedFile.delete();

System.out.println("Done");

 

10） 在VS Code中调试或执行，右键选择Run/Debug

 

全部代码

App.java文件

package com.blobs.quickstart;

/**
* Azure blob storage v12 SDK quickstart
*/
import com.azure.storage.blob.*;
import com.azure.storage.blob.models.*;
import java.io.*;

public class App
{
public static void main( String[] args ) throws IOException
{
System.out.println("Azure Blob storage v12 - Java quickstart sample\n");

// Retrieve the connection string for use with the application. The storage
// connection string is stored in an environment variable on the machine
// running the application called AZURE_STORAGE_CONNECTION_STRING. If the environment variable
// is created after the application is launched in a console or with
// Visual Studio, the shell or application needs to be closed and reloaded
// to take the environment variable into account.
String connectStr ="DefaultEndpointsProtocol=https;AccountName=xxxxxxxx;AccountKey=xxxxxxxxxxxxxxx;EndpointSuffix=core.chinacloudapi.cn";// System.getenv("AZURE_STORAGE_CONNECTION_STRING");

// Create a BlobServiceClient object which will be used to create a container client
BlobServiceClient blobServiceClient = new BlobServiceClientBuilder().connectionString(connectStr).buildClient();

//Create a unique name for the container
String containerName = "quickstartblobs" + java.util.UUID.randomUUID();

// Create the container and return a container client object
BlobContainerClient containerClient = blobServiceClient.createBlobContainer(containerName);

// Create a local file in the ./data/ directory for uploading and downloading
String localPath = "./data/";
String fileName = "quickstart" + java.util.UUID.randomUUID() + ".txt";
File localFile = new File(localPath + fileName);

// Write text to the file
FileWriter writer = new FileWriter(localPath + fileName, true);
writer.write("Hello, World!");
writer.close();

// Get a reference to a blob
BlobClient blobClient = containerClient.getBlobClient(fileName);

System.out.println("\nUploading to Blob storage as blob:\n\t" + blobClient.getBlobUrl());

// Upload the blob
blobClient.uploadFromFile(localPath + fileName);

System.out.println("\nListing blobs...");

// List the blob(s) in the container.
for (BlobItem blobItem : containerClient.listBlobs()) {
System.out.println("\t" + blobItem.getName());
}

// Download the blob to a local file
// Append the string "DOWNLOAD" before the .txt extension so that you can see both files.
String downloadFileName = fileName.replace(".txt", "DOWNLOAD.txt");
File downloadedFile = new File(localPath + downloadFileName);

System.out.println("\nDownloading blob to\n\t " + localPath + downloadFileName);

blobClient.downloadToFile(localPath + downloadFileName);

// Clean up
System.out.println("\nPress the Enter key to begin clean up");
System.console().readLine();

System.out.println("Deleting blob container...");
containerClient.delete();

System.out.println("Deleting the local source and downloaded files...");
localFile.delete();
downloadedFile.delete();

System.out.println("Done");
}
}

 

pom.xml文件

<?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>com.blobs.quickstart</groupId>
<artifactId>blob-quickstart-v12</artifactId>
<version>1.0-SNAPSHOT</version>

<name>blob-quickstart-v12</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>1.7</maven.compiler.source>
<maven.compiler.target>1.7</maven.compiler.target>
</properties>

<dependencies>
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>4.11</version>
<scope>test</scope>
</dependency>
<dependency>
<groupId>com.azure</groupId>
<artifactId>azure-storage-blob</artifactId>
<version>12.6.0</version>
</dependency>
</dependencies>

<build>
<pluginManagement><!-- lock down plugins versions to avoid using Maven defaults (may be moved to parent pom) -->
<plugins>
<!-- clean lifecycle, see https://maven.apache.org/ref/current/maven-core/lifecycles.html#clean_Lifecycle -->
<plugin>
<artifactId>maven-clean-plugin</artifactId>
<version>3.1.0</version>
</plugin>
<!-- default lifecycle, jar packaging: see https://maven.apache.org/ref/current/maven-core/default-bindings.html#Plugin_bindings_for_jar_packaging -->
<plugin>
<artifactId>maven-resources-plugin</artifactId>
<version>3.0.2</version>
</plugin>
<plugin>
<artifactId>maven-compiler-plugin</artifactId>
<version>3.8.0</version>
</plugin>
<plugin>
<artifactId>maven-surefire-plugin</artifactId>
<version>2.22.1</version>
</plugin>
<plugin>
<artifactId>maven-jar-plugin</artifactId>
<version>3.0.2</version>
</plugin>
<plugin>
<artifactId>maven-install-plugin</artifactId>
<version>2.5.2</version>
</plugin>
<plugin>
<artifactId>maven-deploy-plugin</artifactId>
<version>2.8.2</version>
</plugin>
<!-- site lifecycle, see https://maven.apache.org/ref/current/maven-core/lifecycles.html#site_Lifecycle -->
<plugin>
<artifactId>maven-site-plugin</artifactId>
<version>3.7.1</version>
</plugin>
<plugin>
<artifactId>maven-project-info-reports-plugin</artifactId>
<version>3.0.0</version>
</plugin>
</plugins>
</pluginManagement>
</build>
</project>

 

参考资料

Getting Started with Java in VS Code：​​https://code.visualstudio.com/docs/java/java-tutorial​​

快速入门：使用 Java v12 SDK 管理 blob: ​​https://docs.azure.cn/zh-cn/storage/blobs/storage-quickstart-blobs-java#code-examples​​

当在复杂的环境中面临问题，格物之道需：浊而静之徐清，安以动之徐生。 云中，恰是如此!