package com.aws.lhnng; import software.amazon.awssdk.enhanced.dynamodb.*; import software.amazon.awssdk.enhanced.dynamodb.mapper.annotations.DynamoDbBean; import software.amazon.awssdk.enhanced.dynamodb.mapper.annotations.DynamoDbPartitionKey; import software.amazon.awssdk.enhanced.dynamodb.mapper.annotations.DynamoDbSortKey; import software.amazon.awssdk.enhanced.dynamodb.model.*; import software.amazon.awssdk.services.dynamodb.model.*; import java.util.List; import java.util.Map; public class TransactGetItem { public static void main(String[] args){ try{ // Create Client DynamoDbEnhancedClient enhancedClient = DynamoDbEnhancedClient.create(); // Map Tables Using Bean DynamoDbTable customerTable = enhancedClient.table("RetailDatabase", TableSchema.fromBean(Customer.class)); DynamoDbTable productTable = enhancedClient.table("Product", TableSchema.fromBean(Product.class)); // Key for Product Item Key prodKey = Key.builder() .partitionValue("B07J1337PJ42") .build(); // Key for Customer Item Key custKey = Key.builder() .partitionValue("vikram.johnson@somewhere.com") .sortValue("metadata") .build(); TransactGetItemsEnhancedRequest transactGetItemsEnhancedRequest = TransactGetItemsEnhancedRequest.builder() .addGetItem(productTable, prodKey) .addGetItem(customerTable, custKey) .build(); /* TransactGetItems This uses the Enhanced Client and not the Mapped Table Resource */ List response = enhancedClient.transactGetItems(transactGetItemsEnhancedRequest); System.out.println(response.get(0).getItem(productTable).getId()); System.out.println(response.get(1).getItem(customerTable).getPk()); }catch (Exception e){ handleCommonErrors(e); } } @DynamoDbBean public static class Customer { private String pk; private String sk; private String name; private String firstName; private String lastName; private Map address; private String username; private int age; public Customer() { } // Partition Keys @DynamoDbPartitionKey public String getPk() { return pk; } public void setPk(String pk) { this.pk = pk; } @DynamoDbSortKey public String getSk() { return sk; } public void setSk(String sk) { this.sk = sk; } // Attributes public String getName() { return name; } public void setName(String name) { this.name = name; } public String getFirstName() { return firstName; } public void setFirstName(String firstName) { this.firstName = firstName; } public String getLastName() { return lastName; } public void setLastName(String lastName) { this.lastName = lastName; } public Map getAddress() { return address; } public void setAddress(Map address) { this.address = address; } public String getUsername() { return username; } public void setUsername(String username) { this.username = username; } public int getAge() { return age; } public void setAge(int age) { this.age = age; } // Static Builder Class public static class Builder { private String pk; private String sk; private String name; private String firstName; private String lastName; private Map address; private String username; private int age; public Builder(String pk) { this.pk = pk; } public Builder withSk(String sk) { this.sk = sk; return this; } public Builder withName(String name) { this.name = name; return this; } public Builder withFirstName(String firstName) { this.firstName = firstName; return this; } public Builder withLastName(String lastName) { this.lastName = lastName; return this; } public Builder withAddress(Map address){ this.address = address; return this; } public Builder withUsername(String username) { this.username = username; return this; } public Builder withAge(int age) { this.age = age; return this; } public Customer build() { Customer cust = new Customer(); cust.pk = this.pk; cust.sk = this.sk; cust.name = this.name; cust.firstName = this.firstName; cust.lastName = this.lastName; cust.address = this.address; cust.username = this.username; cust.age = this.age; return cust; } } } @DynamoDbBean public static class Product { private String id; private String productStatus; public Product() { } // Partition Keys @DynamoDbPartitionKey public String getId() { return id; } public void setId(String id) { this.id = id; } // Attributes public String getProductStatus() { return productStatus; } public void setProductStatus(String productStatus) { this.productStatus = productStatus; } // Static Builder Class public static class Builder { private String id; private String productStatus; public Builder(String id) { this.id = id; } public Builder withProductStatus(String productStatus) { this.productStatus = productStatus; return this; } public Product build() { Product product = new Product(); product.id = this.id; product.productStatus = this.productStatus; return product; } } } // Exception Helper Method private static void handleCommonErrors(Exception exception) { try { throw exception; } catch (InternalServerErrorException isee) { System.out.println("Internal Server Error, generally safe to retry with exponential back-off. Error: " + isee.getMessage()); } catch (RequestLimitExceededException rlee) { System.out.println("Throughput exceeds the current throughput limit for your account, increase account level throughput before " + "retrying. Error: " + rlee.getMessage()); } catch (ProvisionedThroughputExceededException ptee) { System.out.println("Request rate is too high. If you're using a custom retry strategy make sure to retry with exponential back-off. " + "Otherwise consider reducing frequency of requests or increasing provisioned capacity for your table or secondary index. Error: " + ptee.getMessage()); } catch (ResourceNotFoundException rnfe) { System.out.println("One of the tables was not found, verify table exists before retrying. Error: " + rnfe.getMessage()); } catch (TransactionCanceledException tce) { System.out.println("Transaction Cancelled Error: " + tce.getMessage()); } catch (Exception e) { System.out.println("An exception occurred, investigate and configure retry strategy. Error: " + e.getMessage()); } } }