Навык azure-data-tables-java

Azure Tables SDK for Java

Build table storage applications using the Azure Tables SDK for Java. Works with both Azure Table Storage and Cosmos DB Table API.

Installation

<dependency>
  <groupId>com.azure</groupId>
  <artifactId>azure-data-tables</artifactId>
  <version>12.6.0-beta.1</version>
</dependency>

Client Creation

With Connection String

import com.azure.data.tables.TableServiceClient;
import com.azure.data.tables.TableServiceClientBuilder;
import com.azure.data.tables.TableClient;

TableServiceClient serviceClient = new TableServiceClientBuilder()
    .connectionString("<your-connection-string>")
    .buildClient();

With Shared Key

import com.azure.core.credential.AzureNamedKeyCredential;

AzureNamedKeyCredential credential = new AzureNamedKeyCredential(
    "<account-name>",
    "<account-key>");

TableServiceClient serviceClient = new TableServiceClientBuilder()
    .endpoint("<your-table-account-url>")
    .credential(credential)
    .buildClient();

With SAS Token

TableServiceClient serviceClient = new TableServiceClientBuilder()
    .endpoint("<your-table-account-url>")
    .sasToken("<sas-token>")
    .buildClient();

With DefaultAzureCredential (Storage only)

import com.azure.core.credential.TokenCredential;
import com.azure.identity.AzureIdentityEnvVars;
import com.azure.identity.DefaultAzureCredentialBuilder;
import com.azure.identity.ManagedIdentityCredentialBuilder;

// Local dev: DefaultAzureCredential. Production: set AZURE_TOKEN_CREDENTIALS=prod or AZURE_TOKEN_CREDENTIALS=<specific_credential>
TokenCredential credential = new DefaultAzureCredentialBuilder()
    .requireEnvVars(AzureIdentityEnvVars.AZURE_TOKEN_CREDENTIALS)
    .build();
// Or use a specific credential directly in production:
// See https://learn.microsoft.com/java/api/overview/azure/identity-readme?view=azure-java-stable#credential-classes
// TokenCredential credential = new ManagedIdentityCredentialBuilder().build();

TableServiceClient serviceClient = new TableServiceClientBuilder()
    .endpoint("<your-table-account-url>")
    .credential(credential)
    .buildClient();

Key Concepts

• TableServiceClient: Manage tables (create, list, delete)
• TableClient: Manage entities within a table (CRUD)
• Partition Key: Groups entities for efficient queries
• Row Key: Unique identifier within a partition
• Entity: A row with up to 252 properties (1MB Storage, 2MB Cosmos)

Core Patterns

Create Table

// Create table (throws if exists)
TableClient tableClient = serviceClient.createTable("mytable");

// Create if not exists (no exception)
TableClient tableClient = serviceClient.createTableIfNotExists("mytable");

Get Table Client

// From service client
TableClient tableClient = serviceClient.getTableClient("mytable");

// Direct construction
TableClient tableClient = new TableClientBuilder()
    .connectionString("<connection-string>")
    .tableName("mytable")
    .buildClient();

Create Entity

import com.azure.data.tables.models.TableEntity;

TableEntity entity = new TableEntity("partitionKey", "rowKey")
    .addProperty("Name", "Product A")
    .addProperty("Price", 29.99)
    .addProperty("Quantity", 100)
    .addProperty("IsAvailable", true);

tableClient.createEntity(entity);

Get Entity

TableEntity entity = tableClient.getEntity("partitionKey", "rowKey");

String name = (String) entity.getProperty("Name");
Double price = (Double) entity.getProperty("Price");
System.out.printf("Product: %s, Price: %.2f%n", name, price);

Update Entity

import com.azure.data.tables.models.TableEntityUpdateMode;

// Merge (update only specified properties)
TableEntity updateEntity = new TableEntity("partitionKey", "rowKey")
    .addProperty("Price", 24.99);
tableClient.updateEntity(updateEntity, TableEntityUpdateMode.MERGE);

// Replace (replace entire entity)
TableEntity replaceEntity = new TableEntity("partitionKey", "rowKey")
    .addProperty("Name", "Product A Updated")
    .addProperty("Price", 24.99)
    .addProperty("Quantity", 150);
tableClient.updateEntity(replaceEntity, TableEntityUpdateMode.REPLACE);

Upsert Entity

// Insert or update (merge mode)
tableClient.upsertEntity(entity, TableEntityUpdateMode.MERGE);

// Insert or replace
tableClient.upsertEntity(entity, TableEntityUpdateMode.REPLACE);

Delete Entity

tableClient.deleteEntity("partitionKey", "rowKey");

List Entities

import com.azure.data.tables.models.ListEntitiesOptions;

// List all entities
for (TableEntity entity : tableClient.listEntities()) {
    System.out.printf("%s - %s%n",
        entity.getPartitionKey(),
        entity.getRowKey());
}

// With filtering and selection
ListEntitiesOptions options = new ListEntitiesOptions()
    .setFilter("PartitionKey eq 'sales'")
    .setSelect("Name", "Price");

for (TableEntity entity : tableClient.listEntities(options, null, null)) {
    System.out.printf("%s: %.2f%n",
        entity.getProperty("Name"),
        entity.getProperty("Price"));
}

Query with OData Filter

// Filter by partition key
ListEntitiesOptions options = new ListEntitiesOptions()
    .setFilter("PartitionKey eq 'electronics'");

// Filter with multiple conditions
options.setFilter("PartitionKey eq 'electronics' and Price gt 100");

// Filter with comparison operators
options.setFilter("Quantity ge 10 and Quantity le 100");

// Top N results
options.setTop(10);

for (TableEntity entity : tableClient.listEntities(options, null, null)) {
    System.out.println(entity.getRowKey());
}

Batch Operations (Transactions)

import com.azure.data.tables.models.TableTransactionAction;
import com.azure.data.tables.models.TableTransactionActionType;
import java.util.Arrays;

// All entities must have same partition key
List<TableTransactionAction> actions = Arrays.asList(
    new TableTransactionAction(
        TableTransactionActionType.CREATE,
        new TableEntity("batch", "row1").addProperty("Name", "Item 1")),
    new TableTransactionAction(
        TableTransactionActionType.CREATE,
        new TableEntity("batch", "row2").addProperty("Name", "Item 2")),
    new TableTransactionAction(
        TableTransactionActionType.UPSERT_MERGE,
        new TableEntity("batch", "row3").addProperty("Name", "Item 3"))
);

tableClient.submitTransaction(actions);

List Tables

import com.azure.data.tables.models.TableItem;
import com.azure.data.tables.models.ListTablesOptions;

// List all tables
for (TableItem table : serviceClient.listTables()) {
    System.out.println(table.getName());
}

// Filter tables
ListTablesOptions options = new ListTablesOptions()
    .setFilter("TableName eq 'mytable'");

for (TableItem table : serviceClient.listTables(options, null, null)) {
    System.out.println(table.getName());
}

Delete Table

serviceClient.deleteTable("mytable");

Typed Entities

public class Product implements TableEntity {
    private String partitionKey;
    private String rowKey;
    private OffsetDateTime timestamp;
    private String eTag;
    private String name;
    private double price;
    
    // Getters and setters for all fields
    @Override
    public String getPartitionKey() { return partitionKey; }
    @Override
    public void setPartitionKey(String partitionKey) { this.partitionKey = partitionKey; }
    @Override
    public String getRowKey() { return rowKey; }
    @Override
    public void setRowKey(String rowKey) { this.rowKey = rowKey; }
    // ... other getters/setters
    
    public String getName() { return name; }
    public void setName(String name) { this.name = name; }
    public double getPrice() { return price; }
    public void setPrice(double price) { this.price = price; }
}

// Usage
Product product = new Product();
product.setPartitionKey("electronics");
product.setRowKey("laptop-001");
product.setName("Laptop");
product.setPrice(999.99);

tableClient.createEntity(product);

Error Handling

import com.azure.data.tables.models.TableServiceException;

try {
    tableClient.createEntity(entity);
} catch (TableServiceException e) {
    System.out.println("Status: " + e.getResponse().getStatusCode());
    System.out.println("Error: " + e.getMessage());
    // 409 = Conflict (entity exists)
    // 404 = Not Found
}

Environment Variables

# Storage Account
AZURE_TABLES_CONNECTION_STRING=DefaultEndpointsProtocol=https;AccountName=...  # Alternative to Entra ID auth
AZURE_TABLES_ENDPOINT=https://<account>.table.core.windows.net  # Required for all auth methods
AZURE_TOKEN_CREDENTIALS=prod  # Required only if DefaultAzureCredential is used in production

# Cosmos DB Table API
COSMOS_TABLE_ENDPOINT=https://<account>.table.cosmosdb.azure.com  # Alternative endpoint for Cosmos DB Table API

Best Practices

1. Partition Key Design: Choose keys that distribute load evenly
2. Batch Operations: Use transactions for atomic multi-entity updates
3. Query Optimization: Always filter by PartitionKey when possible
4. Select Projection: Only select needed properties for performance
5. Entity Size: Keep entities under 1MB (Storage) or 2MB (Cosmos)

Trigger Phrases

• "Azure Tables Java"
• "table storage SDK"
• "Cosmos DB Table API"
• "NoSQL key-value storage"
• "partition key row key"
• "table entity CRUD"