【Azure Developer】VS Code運行Java 版Azure Storage SDK操做Blob (新建Container, 上傳Blob文件，下載及清理)

時間 2020-12-09

標籤 html java web shell apache api app dom maven 欄目 Java 简体版

原文原文鏈接

問題描述

是否能夠用Java代碼來管理Azure blob？能夠。在代碼中加入azure-storage-blob依賴。便可使用如下類操做Azure Storage Blob。html

BlobServiceClient：BlobServiceClient 類可用於操縱 Azure 存儲資源和 blob 容器。存儲賬戶爲 Blob 服務提供頂級命名空間。
BlobServiceClientBuilder：BlobServiceClientBuilder 類提供流暢的生成器 API，以幫助對 BlobServiceClient 對象的配置和實例化。
BlobContainerClient：BlobContainerClient 類可用於操縱 Azure 存儲容器及其 blob。
BlobClient：BlobClient 類可用於操縱 Azure 存儲 blob。
BlobItem：BlobItem 類表示從對 listBlobs 的調用返回的單個 blob。

執行步驟

首先，設置VS Code上執行Java 代碼的環境，這裏須要的步驟比較多。徹底參考VS Code for Java文檔便可：https://code.visualstudio.com/docs/java/java-tutorial. java

如下是建立項目步驟：web

1）建立blob-quickstart-v12項目shell

跳轉到blob-quickstart-v12目錄，並在目錄中建立一個data目錄，用於在接下來的代碼中建立本地文件及下載bolb中的文件apache

cd blob-quickstart-v12

mkdir data

2) 修改pom.xml，添加對Java azure-storage-blob SDK的依賴api

  <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代碼文件中添加引用app

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的鏈接字符串dom

5）建立blobServiceClient對象，同時調用createBlobContainer方法建立容器maven

        // 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);

6）建立BlobClient對象，同時調用uploadFromFile方法上傳文件(.tx)ui

        // 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);

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

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

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

8）使用blobClient對象的downloadToFile方法下載文件到本地

        // 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對象的delete方法刪除容器

        // 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中調試或執行，右鍵選擇Run/Debug

所有代碼

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>