AWS code-library documentation change
Summary
Updated TTL configuration example with improved error handling and logging imports
Security assessment
Changes focus on error handling improvements (throwing exceptions instead of System.exit) and logging setup, but no security-specific fixes or features are introduced
Diff
diff --git a/code-library/latest/ug/java_2_dynamodb_code_examples.md b/code-library/latest/ug/java_2_dynamodb_code_examples.md index a743a6682..b4e58f0da 100644 --- a//code-library/latest/ug/java_2_dynamodb_code_examples.md +++ b//code-library/latest/ug/java_2_dynamodb_code_examples.md @@ -1386 +1386,2 @@ Describe TTL configuration on an existing DynamoDB table using AWS SDK for Java - import java.util.Optional; + import java.util.logging.Level; + import java.util.logging.Logger; @@ -1387,0 +1389 @@ Describe TTL configuration on an existing DynamoDB table using AWS SDK for Java + public DescribeTimeToLiveResponse describeTTL(final String tableName, final Region region) { @@ -1391,6 +1393,4 @@ Describe TTL configuration on an existing DynamoDB table using AWS SDK for Java - try (DynamoDbClient ddb = DynamoDbClient.builder() - .region(region) - .build()) { - final DescribeTimeToLiveResponse response = ddb.describeTimeToLive(request); - System.out.println(tableName + " description of time to live is " - + response.toString()); + + try (DynamoDbClient ddb = dynamoDbClient != null ? dynamoDbClient : + DynamoDbClient.builder().region(region).build()) { + return ddb.describeTimeToLive(request); @@ -1398,2 +1398,2 @@ Describe TTL configuration on an existing DynamoDB table using AWS SDK for Java - System.err.format("Error: The Amazon DynamoDB table \"%s\" can't be found.\n", tableName); - System.exit(1); + System.err.format(TABLE_NOT_FOUND_ERROR, tableName); + throw e; @@ -1402 +1402,2 @@ Describe TTL configuration on an existing DynamoDB table using AWS SDK for Java - System.exit(1); + throw e; + } @@ -1404 +1404,0 @@ Describe TTL configuration on an existing DynamoDB table using AWS SDK for Java - System.exit(0); @@ -1724 +1724 @@ The following code example shows how to use `Query`. -**SDK for Java 2.x** + * Use the begins_with function in a key condition expression. @@ -1725,0 +1726 @@ The following code example shows how to use `Query`. + * Filter items based on a prefix pattern in the sort key. @@ -1727 +1727,0 @@ The following code example shows how to use `Query`. -###### Note @@ -1729 +1728,0 @@ The following code example shows how to use `Query`. -There's more on GitHub. Find the complete example and learn how to set up and run in the [AWS Code Examples Repository](https://github.com/awsdocs/aws-doc-sdk-examples/tree/main/javav2/example_code/dynamodb#code-examples). @@ -1731 +1730,5 @@ There's more on GitHub. Find the complete example and learn how to set up and ru -Queries a table by using [DynamoDbClient](http://docs.aws.amazon.com/sdk-for-java/latest/reference/software/amazon/awssdk/services/dynamodb/DynamoDbClient.html). + +**SDK for Java 2.x** + + +Query a DynamoDB table using a begins_with condition on the sort key with AWS SDK for Java 2.x. @@ -1734 +1736,0 @@ Queries a table by using [DynamoDbClient](http://docs.aws.amazon.com/sdk-for-jav - import software.amazon.awssdk.regions.Region; @@ -1740,63 +1742 @@ Queries a table by using [DynamoDbClient](http://docs.aws.amazon.com/sdk-for-jav - import java.util.HashMap; - - /** - * Before running this Java V2 code example, set up your development - * environment, including your credentials. - * - * For more information, see the following documentation topic: - * - * https://docs.aws.amazon.com/sdk-for-java/latest/developer-guide/get-started.html - * - * To query items from an Amazon DynamoDB table using the AWS SDK for Java V2, - * its better practice to use the - * Enhanced Client. See the EnhancedQueryRecords example. - */ - public class Query { - public static void main(String[] args) { - final String usage = """ - - Usage: - <tableName> <partitionKeyName> <partitionKeyVal> - - Where: - tableName - The Amazon DynamoDB table to put the item in (for example, Music3). - partitionKeyName - The partition key name of the Amazon DynamoDB table (for example, Artist). - partitionKeyVal - The value of the partition key that should match (for example, Famous Band). - """; - - if (args.length != 3) { - System.out.println(usage); - System.exit(1); - } - - String tableName = args[0]; - String partitionKeyName = args[1]; - String partitionKeyVal = args[2]; - - // For more information about an alias, see: - // https://docs.aws.amazon.com/amazondynamodb/latest/developerguide/Expressions.ExpressionAttributeNames.html - String partitionAlias = "#a"; - - System.out.format("Querying %s", tableName); - System.out.println(""); - Region region = Region.US_EAST_1; - DynamoDbClient ddb = DynamoDbClient.builder() - .region(region) - .build(); - - int count = queryTable(ddb, tableName, partitionKeyName, partitionKeyVal, partitionAlias); - System.out.println("There were " + count + " record(s) returned"); - ddb.close(); - } - - public static int queryTable(DynamoDbClient ddb, String tableName, String partitionKeyName, String partitionKeyVal, - String partitionAlias) { - // Set up an alias for the partition key name in case it's a reserved word. - HashMap<String, String> attrNameAlias = new HashMap<String, String>(); - attrNameAlias.put(partitionAlias, partitionKeyName); - - // Set up mapping of the partition name with the value. - HashMap<String, AttributeValue> attrValues = new HashMap<>(); - attrValues.put(":" + partitionKeyName, AttributeValue.builder() - .s(partitionKeyVal) - .build()); + import software.amazon.awssdk.services.dynamodb.model.ResourceNotFoundException; @@ -1804 +1744,28 @@ Queries a table by using [DynamoDbClient](http://docs.aws.amazon.com/sdk-for-jav - QueryRequest queryReq = QueryRequest.builder() + import java.util.HashMap; + import java.util.Map; + import java.util.logging.Level; + import java.util.logging.Logger; + + public QueryResponse queryWithBeginsWithCondition( + final String tableName, + final String partitionKeyName, + final String partitionKeyValue, + final String sortKeyName, + final String sortKeyPrefix) { + + CodeSampleUtils.validateTableParameters(tableName, partitionKeyName, partitionKeyValue); + CodeSampleUtils.validateStringParameter("Sort key name", sortKeyName); + CodeSampleUtils.validateStringParameter("Sort key prefix", sortKeyPrefix); + + // Create expression attribute names for the column names + final Map<String, String> expressionAttributeNames = new HashMap<>(); + expressionAttributeNames.put(EXPRESSION_ATTRIBUTE_NAME_PK, partitionKeyName); + expressionAttributeNames.put(EXPRESSION_ATTRIBUTE_NAME_SK, sortKeyName); + + // Create expression attribute values for the column values + final Map<String, AttributeValue> expressionAttributeValues = new HashMap<>(); + expressionAttributeValues.put(EXPRESSION_ATTRIBUTE_VALUE_PK, AttributeValue.builder().s(partitionKeyValue).build()); + expressionAttributeValues.put(EXPRESSION_ATTRIBUTE_VALUE_SK_PREFIX, AttributeValue.builder().s(sortKeyPrefix).build()); + + // Create the query request + final QueryRequest queryRequest = QueryRequest.builder() @@ -1806,3 +1773,3 @@ Queries a table by using [DynamoDbClient](http://docs.aws.amazon.com/sdk-for-jav - .keyConditionExpression(partitionAlias + " = :" + partitionKeyName) - .expressionAttributeNames(attrNameAlias) - .expressionAttributeValues(attrValues) + .keyConditionExpression(KEY_CONDITION_EXPRESSION) + .expressionAttributeNames(expressionAttributeNames) + .expressionAttributeValues(expressionAttributeValues) @@ -1812,3 +1779,6 @@ Queries a table by using [DynamoDbClient](http://docs.aws.amazon.com/sdk-for-jav - QueryResponse response = ddb.query(queryReq); - return response.count(); - + final QueryResponse response = dynamoDbClient.query(queryRequest); + LOGGER.log(Level.INFO, "Query with begins_with condition successful. Found {0} items", response.count()); + return response; + } catch (ResourceNotFoundException e) { + LOGGER.log(Level.SEVERE, "Table not found: {0}", tableName); + throw e; @@ -1816,4 +1786,2 @@ Queries a table by using [DynamoDbClient](http://docs.aws.amazon.com/sdk-for-jav - System.err.println(e.getMessage()); - System.exit(1); - } - return -1; + LOGGER.log(Level.SEVERE, "Error querying with begins_with condition", e); + throw e; @@ -1825 +1793 @@ Queries a table by using [DynamoDbClient](http://docs.aws.amazon.com/sdk-for-jav -Queries a table by using `DynamoDbClient` and a secondary index. +Demonstrate using begins_with with different prefix lengths with AWS SDK for Java 2.x. @@ -1828,25 +1795,0 @@ Queries a table by using `DynamoDbClient` and a secondary index. - import software.amazon.awssdk.regions.Region; - import software.amazon.awssdk.services.dynamodb.DynamoDbClient; - import software.amazon.awssdk.services.dynamodb.model.AttributeValue; - import software.amazon.awssdk.services.dynamodb.model.DynamoDbException; - import software.amazon.awssdk.services.dynamodb.model.QueryRequest; - import software.amazon.awssdk.services.dynamodb.model.QueryResponse; - import java.util.HashMap; - import java.util.Map; - - /** - * Before running this Java V2 code example, set up your development - * environment, including your credentials. - * - * For more information, see the following documentation topic: - * - * https://docs.aws.amazon.com/sdk-for-java/latest/developer-guide/get-started.html - * - * Create the Movies table by running the Scenario example and loading the Movie - * data from the JSON file. Next create a secondary - * index for the Movies table that uses only the year column. Name the index - * **year-index**. For more information, see: - * - * https://docs.aws.amazon.com/amazondynamodb/latest/developerguide/GSI.html - */ - public class QueryItemsUsingIndex { @@ -1854,11 +1796,0 @@ Queries a table by using `DynamoDbClient` and a secondary index. - String tableName = "Movies";