azure-cosmos-java

作者原文

Azure Cosmos DB SDK for Java. NoSQL database operations with global distribution, multi-model support, and reactive patterns. Triggers: "CosmosClient java", "CosmosAsyncClient", "cosmos database java", "cosmosdb java", "document database java".

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能完成的任务

azure-cosmos-java

适合谁

按原作者介绍判断适用范围。

输入和输出

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软件、账号及付费要求

本包是 azure-cosmos-java 的 Microsoft Azure SDK 文档与示例，不含已验证的可执行安装程序。使用示例前核对 SDK 包名、版本、Azure 租户/订阅和实际终结点，仅授予本任务所需的最小权限；不把管理员凭据或真实机密写进示例、日志或提交。示例连接的云服务可能接收所选文本、文档、音频、消息、日志或其他输入并产生费用；确认数据范围、脱敏及费用后再连接。创建、更新、删除资源、密钥/权限变更或发送消息须由用户逐项确认，在测试资源上验证，避免生产数据覆盖与不可逆操作。文档中的占位终结点和样例输入必须替换并核对；网站仅核对固定源版本、完整附件和静态/病毒库证据，未运行 SDK、验证外部服务兼容性或授权任何云访问。

限制与区别

原作者介绍原样保留，中文为对应翻译。文档示例未经本站运行；版本、兼容性和效果为作者陈述。

实测状态

未测试

安全评级与访问范围

caution · 静态证据核验，不代表运行安全保证。

本包是 azure-cosmos-java 的 Microsoft Azure SDK 文档与示例，不含已验证的可执行安装程序。使用示例前核对 SDK 包名、版本、Azure 租户/订阅和实际终结点，仅授予本任务所需的最小权限；不把管理员凭据或真实机密写进示例、日志或提交。示例连接的云服务可能接收所选文本、文档、音频、消息、日志或其他输入并产生费用；确认数据范围、脱敏及费用后再连接。创建、更新、删除资源、密钥/权限变更或发送消息须由用户逐项确认，在测试资源上验证，避免生产数据覆盖与不可逆操作。文档中的占位终结点和样例输入必须替换并核对；网站仅核对固定源版本、完整附件和静态/病毒库证据，未运行 SDK、验证外部服务兼容性或授权任何云访问。

使用前请由宿主核对并授权实际文件读写、外部服务和联网目的地；本站的核验不会授予任何运行权限。

原始 SKILL.md

---
name: azure-cosmos-java
description: |
  Azure Cosmos DB SDK for Java. NoSQL database operations with global distribution, multi-model support, and reactive patterns.
  Triggers: "CosmosClient java", "CosmosAsyncClient", "cosmos database java", "cosmosdb java", "document database java".
license: MIT
metadata:
  author: Microsoft
  version: "1.0.0"
  package: azure-cosmos
---

# Azure Cosmos DB SDK for Java

Client library for Azure Cosmos DB NoSQL API with global distribution and reactive patterns.

## Installation

```xml
<dependency>
    <groupId>com.azure</groupId>
    <artifactId>azure-cosmos</artifactId>
    <version>LATEST</version>
</dependency>
```

Or use Azure SDK BOM:

```xml
<dependencyManagement>
    <dependencies>
        <dependency>
            <groupId>com.azure</groupId>
            <artifactId>azure-sdk-bom</artifactId>
            <version>{bom_version}</version>
            <type>pom</type>
            <scope>import</scope>
        </dependency>
    </dependencies>
</dependencyManagement>

<dependencies>
    <dependency>
        <groupId>com.azure</groupId>
        <artifactId>azure-cosmos</artifactId>
    </dependency>
</dependencies>
```

## Environment Variables

```bash
COSMOS_ENDPOINT=https://<account>.documents.azure.com:443/
COSMOS_KEY=<your-primary-key>
```

## Authentication

### Key-based Authentication

```java
import com.azure.cosmos.CosmosClient;
import com.azure.cosmos.CosmosClientBuilder;

CosmosClient client = new CosmosClientBuilder()
    .endpoint(System.getenv("COSMOS_ENDPOINT"))
    .key(System.getenv("COSMOS_KEY"))
    .buildClient();
```

### Async Client

```java
import com.azure.cosmos.CosmosAsyncClient;

CosmosAsyncClient asyncClient = new CosmosClientBuilder()
    .endpoint(serviceEndpoint)
    .key(key)
    .buildAsyncClient();
```

### With Customizations

```java
import com.azure.cosmos.ConsistencyLevel;
import java.util.Arrays;

CosmosClient client = new CosmosClientBuilder()
    .endpoint(serviceEndpoint)
    .key(key)
    .directMode(directConnectionConfig, gatewayConnectionConfig)
    .consistencyLevel(ConsistencyLevel.SESSION)
    .connectionSharingAcrossClientsEnabled(true)
    .contentResponseOnWriteEnabled(true)
    .userAgentSuffix("my-application")
    .preferredRegions(Arrays.asList("West US", "East US"))
    .buildClient();
```

## Client Hierarchy

| Class | Purpose |
|-------|---------|
| `CosmosClient` / `CosmosAsyncClient` | Account-level operations |
| `CosmosDatabase` / `CosmosAsyncDatabase` | Database operations |
| `CosmosContainer` / `CosmosAsyncContainer` | Container/item operations |

## Core Workflow

### Create Database

```java
// Sync
client.createDatabaseIfNotExists("myDatabase")
    .map(response -> client.getDatabase(response.getProperties().getId()));

// Async with chaining
asyncClient.createDatabaseIfNotExists("myDatabase")
    .map(response -> asyncClient.getDatabase(response.getProperties().getId()))
    .subscribe(database -> System.out.println("Created: " + database.getId()));
```

### Create Container

```java
asyncClient.createDatabaseIfNotExists("myDatabase")
    .flatMap(dbResponse -> {
        String databaseId = dbResponse.getProperties().getId();
        return asyncClient.getDatabase(databaseId)
            .createContainerIfNotExists("myContainer", "/partitionKey")
            .map(containerResponse -> asyncClient.getDatabase(databaseId)
                .getContainer(containerResponse.getProperties().getId()));
    })
    .subscribe(container -> System.out.println("Container: " + container.getId()));
```

### CRUD Operations

```java
import com.azure.cosmos.models.PartitionKey;

CosmosAsyncContainer container = asyncClient
    .getDatabase("myDatabase")
    .getContainer("myContainer");

// Create
container.createItem(new User("1", "John Doe", "john@example.com"))
    .flatMap(response -> {
        System.out.println("Created: " + response.getItem());
        // Read
        return container.readItem(
            response.getItem().getId(),
            new PartitionKey(response.getItem().getId()),
            User.class);
    })
    .flatMap(response -> {
        System.out.println("Read: " + response.getItem());
        // Update
        User user = response.getItem();
        user.setEmail("john.doe@example.com");
        return container.replaceItem(
            user,
            user.getId(),
            new PartitionKey(user.getId()));
    })
    .flatMap(response -> {
        // Delete
        return container.deleteItem(
            response.getItem().getId(),
            new PartitionKey(response.getItem().getId()));
    })
    .block();
```

### Query Documents

```java
import com.azure.cosmos.models.CosmosQueryRequestOptions;
import com.azure.cosmos.util.CosmosPagedIterable;

CosmosContainer container = client.getDatabase("myDatabase").getContainer("myContainer");

String query = "SELECT * FROM c WHERE c.status = @status";
CosmosQueryRequestOptions options = new CosmosQueryRequestOptions();

CosmosPagedIterable<User> results = container.queryItems(
    query,
    options,
    User.class
);

results.forEach(user -> System.out.println("User: " + user.getName()));
```

## Key Concepts

### Partition Keys

Choose a partition key with:
- High cardinality (many distinct values)
- Even distribution of data and requests
- Frequently used in queries

### Consistency Levels

| Level | Guarantee |
|-------|-----------|
| Strong | Linearizability |
| Bounded Staleness | Consistent prefix with bounded lag |
| Session | Consistent prefix within session |
| Consistent Prefix | Reads never see out-of-order writes |
| Eventual | No ordering guarantee |

### Request Units (RUs)

All operations consume RUs. Check response headers:

```java
CosmosItemResponse<User> response = container.createItem(user);
System.out.println("RU charge: " + response.getRequestCharge());
```

## Best Practices

1. **Reuse CosmosClient** — Create once, reuse throughout application
2. **Use async client** for high-throughput scenarios
3. **Choose partition key carefully** — Affects performance and scalability
4. **Enable content response on write** for immediate access to created items
5. **Configure preferred regions** for geo-distributed applications
6. **Handle 429 errors** with retry policies (built-in by default)
7. **Use direct mode** for lowest latency in production

## Error Handling

```java
import com.azure.cosmos.CosmosException;

try {
    container.createItem(item);
} catch (CosmosException e) {
    System.err.println("Status: " + e.getStatusCode());
    System.err.println("Message: " + e.getMessage());
    System.err.println("Request charge: " + e.getRequestCharge());
    
    if (e.getStatusCode() == 409) {
        System.err.println("Item already exists");
    } else if (e.getStatusCode() == 429) {
        System.err.println("Rate limited, retry after: " + e.getRetryAfterDuration());
    }
}
```

## Reference Links

| Resource | URL |
|----------|-----|
| Maven Package | https://central.sonatype.com/artifact/com.azure/azure-cosmos |
| API Documentation | https://azuresdkdocs.z19.web.core.windows.net/java/azure-cosmos/latest/index.html |
| Product Docs | https://learn.microsoft.com/azure/cosmos-db/ |
| Samples | https://github.com/Azure-Samples/azure-cosmos-java-sql-api-samples |
| Performance Guide | https://learn.microsoft.com/azure/cosmos-db/performance-tips-java-sdk-v4-sql |
| Troubleshooting | https://learn.microsoft.com/azure/cosmos-db/troubleshoot-java-sdk-v4-sql |

版权与许可声明

    MIT License

    Copyright (c) Microsoft Corporation.

    Permission is hereby granted, free of charge, to any person obtaining a copy
    of this software and associated documentation files (the "Software"), to deal
    in the Software without restriction, including without limitation the rights
    to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
    copies of the Software, and to permit persons to whom the Software is
    furnished to do so, subject to the following conditions:

    The above copyright notice and this permission notice shall be included in all
    copies or substantial portions of the Software.

    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
    IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
    FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
    AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
    LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
    OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
    SOFTWARE