尝试运行DynamoDB Java示例客户端程序时出现以下异常： 捕获了AmazonClientException，这意味着客户端在尝试与AWS通信时遇到了严重的内部问题，例如无法访问网络。 错误消息：无法执行HTTP请求：这通常是主机名解析期间的临时错误，表示本地服务器未收到权威服务器的响应
请提供给我的建议如何解决此问题。我曾尝试使用ClientConfiguration设置代理，但错误仍然相同。 P.S。我有我的accesskeys工作，因为我可以在eclipse
中从AWS Toolkit创建DynamoDB表完整的应用程序代码如下：
/*
* Copyright 2012-2017 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.ClientConfiguration;
import com.amazonaws.Protocol;
import com.amazonaws.auth.AWSCredentials;
import com.amazonaws.auth.profile.ProfileCredentialsProvider;
import com.amazonaws.regions.Region;
import com.amazonaws.regions.Regions;
import com.amazonaws.services.dynamodbv2.AmazonDynamoDBClient;
import com.amazonaws.services.dynamodbv2.model.AttributeDefinition;
import com.amazonaws.services.dynamodbv2.model.AttributeValue;
import com.amazonaws.services.dynamodbv2.model.ComparisonOperator;
import com.amazonaws.services.dynamodbv2.model.Condition;
import com.amazonaws.services.dynamodbv2.model.CreateTableRequest;
import com.amazonaws.services.dynamodbv2.model.DescribeTableRequest;
import com.amazonaws.services.dynamodbv2.model.KeySchemaElement;
import com.amazonaws.services.dynamodbv2.model.KeyType;
import com.amazonaws.services.dynamodbv2.model.ProvisionedThroughput;
import com.amazonaws.services.dynamodbv2.model.PutItemRequest;
import com.amazonaws.services.dynamodbv2.model.PutItemResult;
import com.amazonaws.services.dynamodbv2.model.ScalarAttributeType;
import com.amazonaws.services.dynamodbv2.model.ScanRequest;
import com.amazonaws.services.dynamodbv2.model.ScanResult;
import com.amazonaws.services.dynamodbv2.model.TableDescription;
import com.amazonaws.services.dynamodbv2.util.TableUtils;
/**
* This sample demonstrates how to perform a few simple operations with the
* Amazon DynamoDB service.
*/
public class AmazonDynamoDBSample {
/*
* Before running the code:
* Fill in your AWS access credentials in the provided credentials
* file template, and be sure to move the file to the default location
* (C:\\Users\\245819\\.aws\\credentials) where the sample code will load the
* credentials from.
* https://console.aws.amazon.com/iam/home?#security_credential
*
* WARNING:
* To avoid accidental leakage of your credentials, DO NOT keep
* the credentials file in your source directory.
*/
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.ProfilesConfigFile
* @see com.amazonaws.ClientConfiguration
*/
private static void init() throws Exception {
/*
* The ProfileCredentialsProvider will return your [default]
* credential profile by reading from the credentials file located at
* (C:\\Users\\245819\\.aws\\credentials).
*/
AWSCredentials credentials = null;
try {
credentials = new ProfileCredentialsProvider("AWS NEW").getCredentials();
} catch (Exception e) {
throw new AmazonClientException(
"Cannot load the credentials from the credential profiles file. " +
"Please make sure that your credentials file is at the correct " +
"location (C:\\Users\\245819\\.aws\\credentials), and is in valid format.",
e);
}
dynamoDB = new AmazonDynamoDBClient(credentials);
Region sAsiaEast1 = Region.getRegion(Regions.AP_SOUTHEAST_1);
dynamoDB.setRegion(sAsiaEast1);
}
public static void main(String[] args) throws Exception {
init();
try {
String tableName = "my-favorite-movies-table";
/* ClientConfiguration clientCfg = new ClientConfiguration();
clientCfg.setProtocol(Protocol.HTTP);
clientCfg.setProxyHost("proxy.tcs.com");
clientCfg.setProxyPort(80);
clientCfg.setProxyUsername("245819");
clientCfg.setProxyPassword("Kolkata@31");
*/
// Create a table with a primary hash key named 'name', which holds a string
CreateTableRequest createTableRequest = new CreateTableRequest().withTableName(tableName)
.withKeySchema(new KeySchemaElement().withAttributeName("name").withKeyType(KeyType.HASH))
.withAttributeDefinitions(new AttributeDefinition().withAttributeName("name").withAttributeType(ScalarAttributeType.S))
.withProvisionedThroughput(new ProvisionedThroughput().withReadCapacityUnits(1L).withWriteCapacityUnits(1L));
// Create table if it does not exist yet
TableUtils.createTableIfNotExists(dynamoDB, createTableRequest);
// wait for the table to move into ACTIVE state
TableUtils.waitUntilActive(dynamoDB, 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;
}
}