Java tutorial
/* * Copyright 2012 Amazon.com, Inc. or its affiliates. All Rights Reserved. * * Licensed under the Apache License, Version 2.0 (the "License"). * You may not use this file except in compliance with the License. * A copy of the License is located at * * http://aws.amazon.com/apache2.0 * * or in the "license" file accompanying this file. This file is distributed * on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either * express or implied. See the License for the specific language governing * permissions and limitations under the License. */ import java.util.HashMap; import java.util.Map; import com.amazonaws.AmazonClientException; import com.amazonaws.AmazonServiceException; import com.amazonaws.auth.AWSCredentials; import com.amazonaws.auth.PropertiesCredentials; import com.amazonaws.services.dynamodb.AmazonDynamoDBClient; import com.amazonaws.services.dynamodb.model.AttributeValue; import com.amazonaws.services.dynamodb.model.ComparisonOperator; import com.amazonaws.services.dynamodb.model.Condition; import com.amazonaws.services.dynamodb.model.CreateTableRequest; import com.amazonaws.services.dynamodb.model.DescribeTableRequest; import com.amazonaws.services.dynamodb.model.KeySchema; import com.amazonaws.services.dynamodb.model.KeySchemaElement; import com.amazonaws.services.dynamodb.model.ProvisionedThroughput; import com.amazonaws.services.dynamodb.model.PutItemRequest; import com.amazonaws.services.dynamodb.model.PutItemResult; import com.amazonaws.services.dynamodb.model.ScanRequest; import com.amazonaws.services.dynamodb.model.ScanResult; import com.amazonaws.services.dynamodb.model.TableDescription; import com.amazonaws.services.dynamodb.model.TableStatus; /** * This sample demonstrates how to perform a few simple operations with the * Amazon DynamoDB service. */ public class AmazonDynamoDBSample { /* * Important: Be sure to fill in your AWS access credentials in the * AwsCredentials.properties file before you try to run this * sample. * http://aws.amazon.com/security-credentials */ static AmazonDynamoDBClient dynamoDB; /** * The only information needed to create a client are security credentials * consisting of the AWS Access Key ID and Secret Access Key. All other * configuration, such as the service endpoints, are performed * automatically. Client parameters, such as proxies, can be specified in an * optional ClientConfiguration object when constructing a client. * * @see com.amazonaws.auth.BasicAWSCredentials * @see com.amazonaws.auth.PropertiesCredentials * @see com.amazonaws.ClientConfiguration */ private static void init() throws Exception { AWSCredentials credentials = new PropertiesCredentials( AmazonDynamoDBSample.class.getResourceAsStream("AwsCredentials.properties")); dynamoDB = new AmazonDynamoDBClient(credentials); } public static void main(String[] args) throws Exception { init(); try { String tableName = "my-favorite-movies-table"; // Create a table with a primary key named 'name', which holds a string CreateTableRequest createTableRequest = new CreateTableRequest().withTableName(tableName) .withKeySchema( new KeySchema(new KeySchemaElement().withAttributeName("name").withAttributeType("S"))) .withProvisionedThroughput( new ProvisionedThroughput().withReadCapacityUnits(10L).withWriteCapacityUnits(10L)); TableDescription createdTableDescription = dynamoDB.createTable(createTableRequest) .getTableDescription(); System.out.println("Created Table: " + createdTableDescription); // Wait for it to become active waitForTableToBecomeAvailable(tableName); // Describe our new table DescribeTableRequest describeTableRequest = new DescribeTableRequest().withTableName(tableName); TableDescription tableDescription = dynamoDB.describeTable(describeTableRequest).getTable(); System.out.println("Table Description: " + tableDescription); // Add an item Map<String, AttributeValue> item = newItem("Bill & Ted's Excellent Adventure", 1989, "****", "James", "Sara"); PutItemRequest putItemRequest = new PutItemRequest(tableName, item); PutItemResult putItemResult = dynamoDB.putItem(putItemRequest); System.out.println("Result: " + putItemResult); // Add another item item = newItem("Airplane", 1980, "*****", "James", "Billy Bob"); putItemRequest = new PutItemRequest(tableName, item); putItemResult = dynamoDB.putItem(putItemRequest); System.out.println("Result: " + putItemResult); // Scan items for movies with a year attribute greater than 1985 HashMap<String, Condition> scanFilter = new HashMap<String, Condition>(); Condition condition = new Condition().withComparisonOperator(ComparisonOperator.GT.toString()) .withAttributeValueList(new AttributeValue().withN("1985")); scanFilter.put("year", condition); ScanRequest scanRequest = new ScanRequest(tableName).withScanFilter(scanFilter); ScanResult scanResult = dynamoDB.scan(scanRequest); System.out.println("Result: " + scanResult); } catch (AmazonServiceException ase) { System.out.println("Caught an AmazonServiceException, which means your request made it " + "to AWS, but was rejected with an error response for some reason."); System.out.println("Error Message: " + ase.getMessage()); System.out.println("HTTP Status Code: " + ase.getStatusCode()); System.out.println("AWS Error Code: " + ase.getErrorCode()); System.out.println("Error Type: " + ase.getErrorType()); System.out.println("Request ID: " + ase.getRequestId()); } catch (AmazonClientException ace) { System.out.println("Caught an AmazonClientException, which means the client encountered " + "a serious internal problem while trying to communicate with AWS, " + "such as not being able to access the network."); System.out.println("Error Message: " + ace.getMessage()); } } private static Map<String, AttributeValue> newItem(String name, int year, String rating, String... fans) { Map<String, AttributeValue> item = new HashMap<String, AttributeValue>(); item.put("name", new AttributeValue(name)); item.put("year", new AttributeValue().withN(Integer.toString(year))); item.put("rating", new AttributeValue(rating)); item.put("fans", new AttributeValue().withSS(fans)); return item; } private static void waitForTableToBecomeAvailable(String tableName) { System.out.println("Waiting for " + tableName + " to become ACTIVE..."); long startTime = System.currentTimeMillis(); long endTime = startTime + (10 * 60 * 1000); while (System.currentTimeMillis() < endTime) { try { Thread.sleep(1000 * 20); } catch (Exception e) { } try { DescribeTableRequest request = new DescribeTableRequest().withTableName(tableName); TableDescription tableDescription = dynamoDB.describeTable(request).getTable(); String tableStatus = tableDescription.getTableStatus(); System.out.println(" - current state: " + tableStatus); if (tableStatus.equals(TableStatus.ACTIVE.toString())) return; } catch (AmazonServiceException ase) { if (ase.getErrorCode().equalsIgnoreCase("ResourceNotFoundException") == false) throw ase; } } throw new RuntimeException("Table " + tableName + " never went active"); } }