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+# AWS SDK for Java 2.x Developer Guide
+
+## Overview
+
+The AWS SDK for Java 2.x provides a modern, type-safe API for AWS services. Built on Java 8+, it offers improved performance, better error handling, and enhanced security compared to v1.x.
+
+## Key Features
+
+- **Modern Architecture**: Built on Java 8+ with reactive and async support
+- **Type Safety**: Comprehensive type annotations and validation
+- **Performance Optimized**: Connection pooling, async support, and SSL optimization
+- **Enhanced Security**: Better credential management and security practices
+- **Extensive Coverage**: Support for all AWS services with regular updates
+
+## Core Concepts
+
+### Service Clients
+The primary interface for interacting with AWS services. All clients implement the `SdkClient` interface.
+
+```java
+// S3Client example
+S3Client s3 = S3Client.builder().region(Region.US_EAST_1).build();
+```
+
+### Client Configuration
+Configure behavior through builders supporting:
+- Timeout settings
+- HTTP client selection
+- Authentication methods
+- Monitoring and metrics
+
+### Credential Providers
+Multiple authentication methods:
+- Environment variables
+- System properties
+- Shared credential files
+- IAM roles
+- SSO integration
+
+### HTTP Clients
+Choose from three HTTP implementations:
+- Apache HttpClient (synchronous)
+- Netty NIO Client (asynchronous)
+- URL Connection Client (lightweight)
+
+## Migration from v1.x
+
+The SDK 2.x is not backward compatible with v1.x. Key changes:
+- Builder pattern for client creation
+- Different package structure
+- Enhanced error handling
+- New credential system
+- Improved resource management
+
+## Getting Started
+
+Include the BOM (Bill of Materials) for version management:
+
+```xml
+<dependencyManagement>
+    <dependencies>
+        <dependency>
+            <groupId>software.amazon.awssdk</groupId>
+            <artifactId>bom</artifactId>
+            <version>2.25.0</version> // Use latest stable version
+            <type>pom</type>
+            <scope>import</scope>
+        </dependency>
+    </dependencies>
+</dependencyManagement>
+```
+
+Add service-specific dependencies:
+
+```xml
+<dependencies>
+    <!-- S3 Service -->
+    <dependency>
+        <groupId>software.amazon.awssdk</groupId>
+        <artifactId>s3</artifactId>
+    </dependency>
+
+    <!-- Core SDK -->
+    <dependency>
+        <groupId>software.amazon.awssdk</groupId>
+        <artifactId>sdk-core</artifactId>
+    </dependency>
+</dependencies>
+```
+
+## Architecture Overview
+
+```
+AWS Service Client
+├── Configuration Layer
+│   ├── Client Override Configuration
+│   └── HTTP Client Configuration
+├── Authentication Layer
+│   ├── Credential Providers
+│   └── Security Context
+├── Transport Layer
+│   ├── HTTP Client (Apache/Netty/URLConn)
+│   └── Connection Pool
+└── Protocol Layer
+    ├── Service Protocol Implementation
+    └── Error Handling
+```
+
+## Service Discovery
+
+The SDK automatically discovers and registers all available AWS services through service interfaces and paginators.
+
+### Available Services
+
+All AWS services are available through dedicated client interfaces:
+- S3 (Simple Storage Service)
+- DynamoDB (NoSQL Database)
+- Lambda (Serverless Functions)
+- EC2 (Compute Cloud)
+- RDS (Managed Databases)
+- And 200+ other services
+
+For a complete list, see the AWS Service documentation.
+
+## Support and Community
+
+- **GitHub Issues**: Report bugs and request features
+- **AWS Amplify**: For mobile app developers
+- **Migration Guide**: Available for v1.x users
+- **Changelog**: Track changes on GitHub