public void sample() {
	IClientProfile profile = DefaultProfile.getProfile("cn-hangzhou", "<your accessKey>", "<your accessSecret>");
	IAcsClient client = new DefaultAcsClient(profile);
	DescribeRegionsRequest describeRegionsRequest = new DescribeRegionsRequest();
	try {
		DescribeRegionsResponse describeRegionsResponse = client.getAcsResponse(describeRegionsRequest);
		//todo something.
	} 
	catch (ServerException e) {
		//todo something.
	}
	catch (ClientException e) {
		//todo something.
	}
}