import com.amazonaws.auth.policy.actions.SQSActions; //导入依赖的package包/类
public String subscribeQueueToTopic(String snsTopicArn, String sqsQueueUrl){		
       Map<String, String> queueAttributes = sqsClient.getQueueAttributes(new GetQueueAttributesRequest(sqsQueueUrl)
               .withAttributeNames(QueueAttributeName.QueueArn.toString())).getAttributes();
       String sqsQueueArn = queueAttributes.get(QueueAttributeName.QueueArn.toString());

       Policy policy = new Policy().withStatements(
               new Statement(Effect.Allow)
                   .withId("topic-subscription-" + snsTopicArn)
                   .withPrincipals(Principal.AllUsers)
                   .withActions(SQSActions.SendMessage)
                   .withResources(new Resource(sqsQueueArn))
                   .withConditions(ConditionFactory.newSourceArnCondition(snsTopicArn)));

       logger.debug("Policy: " + policy.toJson());

       queueAttributes = new HashMap<String, String>();
       queueAttributes.put(QueueAttributeName.Policy.toString(), policy.toJson());
       sqsClient.setQueueAttributes(new SetQueueAttributesRequest(sqsQueueUrl, queueAttributes));

       SubscribeResult subscribeResult =
               snsClient.subscribe(new SubscribeRequest()
                   .withEndpoint(sqsQueueArn)
                   .withProtocol("sqs")
                   .withTopicArn(snsTopicArn));
       return subscribeResult.getSubscriptionArn();
}
 

import com.amazonaws.auth.policy.actions.SQSActions; //导入依赖的package包/类
private void setQueuePolicy(String topicSnsArn, String queueArn, String queueURL) {
	logger.info("Set up policy for queue to allow SNS to publish to it");
	Policy sqsPolicy = new Policy()
       .withStatements(new Statement(Statement.Effect.Allow)
                           .withPrincipals(Principal.AllUsers)
                           .withResources(new Resource(queueArn))
                           .withConditions(ConditionFactory.newSourceArnCondition(topicSnsArn))
                           .withActions(SQSActions.SendMessage));
	
       Map<String, String> attributes = new HashMap<String,String>();
       attributes.put("Policy", sqsPolicy.toJson());
       
       SetQueueAttributesRequest setQueueAttributesRequest = new SetQueueAttributesRequest();
       setQueueAttributesRequest.setQueueUrl(queueURL);
       setQueueAttributesRequest.setAttributes(attributes);
       sqsClient.setQueueAttributes(setQueueAttributesRequest);		
}
 

import com.amazonaws.auth.policy.actions.SQSActions; //导入依赖的package包/类
private String getPolicy(List<String> accountIds) {
	Policy policy = new Policy("AuthorizedWorkerAccessPolicy");
	Statement stmt = new Statement(Effect.Allow);
	Action action = SQSActions.SendMessage;
	stmt.getActions().add(action);
	stmt.setResources(new LinkedList<>());
	for(String accountId : accountIds) {
		Principal principal = new Principal(accountId);
		stmt.getPrincipals().add(principal);
	}
	stmt.getResources().add(new Resource(getQueueARN()));
	policy.getStatements().add(stmt);
	return policy.toJson();
}
 

import com.amazonaws.auth.policy.actions.SQSActions; //导入依赖的package包/类
private boolean allowQueuePublish(Statement statement) {
	if (statement.getEffect().equals(Statement.Effect.Allow)) {
		List<Action> actions = statement.getActions();

		for(Action action : actions) { // .equals not properly defined on actions
			if (action.getActionName().equals("sqs:"+SQSActions.SendMessage.toString())) {
				return true;
			}
		}
	}	
	return false;
}
 

import com.amazonaws.auth.policy.actions.SQSActions; //导入依赖的package包/类
private static void allowSQSQueueToReceiveMessagesFromSNSTopic(
    AmazonSQS amazonSQS,
    String queueURL,
    String queueARN,
    String topicARN
) {
    GetQueueAttributesResult queueAttributesResult =
        amazonSQS.getQueueAttributes(
            new GetQueueAttributesRequest().withQueueUrl(queueURL).withAttributeNames(
                QueueAttributeName.Policy
            )
        );

    String policyJson = queueAttributesResult.getAttributes().get(QueueAttributeName.Policy.name());

    final List<Statement> statements;
    if (policyJson != null) {
        statements = new ArrayList<>(Policy.fromJson(policyJson).getStatements());
    } else {
        // no policies yet exist
        statements = new ArrayList<>();
    }

    statements.add(
        new Statement(Statement.Effect.Allow)
            .withPrincipals(Principal.AllUsers)
            .withResources(new Resource(queueARN))
            .withActions(SQSActions.SendMessage)
            .withConditions(ConditionFactory.newSourceArnCondition(topicARN))
    );

    Policy policy = new Policy();
    policy.setStatements(statements);
    Map<String, String> queueAttributes = new HashMap<>();
    queueAttributes.put(QueueAttributeName.Policy.name(), policy.toJson());

    // Note that if the queue already has this policy, this will do nothing.
    amazonSQS.setQueueAttributes(
        new SetQueueAttributesRequest()
            .withQueueUrl(queueURL)
            .withAttributes(queueAttributes)
    );
}