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package com.aliyun.datahub.client.example.examples;

import com.aliyun.datahub.client.DatahubClient;
import com.aliyun.datahub.client.DatahubClientBuilder;
import com.aliyun.datahub.client.auth.AliyunAccount;
import com.aliyun.datahub.client.common.DatahubConfig;
import com.aliyun.datahub.client.exception.*;
import com.aliyun.datahub.client.model.CursorType;

import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Date;

public class CursorExample {
    private static DatahubClient datahubClient;


    public static void init() {

        // 创建DataHubClient实例
        datahubClient = DatahubClientBuilder.newBuilder()
                .setDatahubConfig(
                        new DatahubConfig(Constant.endpoint,
                                new AliyunAccount(Constant.accessId, Constant.accessKey)))
                .build();
    }

    public static void getCursor() {
        String shardId = "0";
        try {
            /* OLDEST用法示例 */
            String oldestCursor = datahubClient.getCursor(Constant.projectName, Constant.topicName, shardId, CursorType.OLDEST).getCursor();

            /* LATEST用法示例 */
            String latestCursor = datahubClient.getCursor(Constant.projectName, Constant.topicName, shardId, CursorType.LATEST).getCursor();

            /* SEQUENCE用法示例 */
            //获取最新数据的sequence
            long seq = datahubClient.getCursor(Constant.projectName, Constant.topicName, shardId, CursorType.LATEST).getSequence();
            //获取最新的十条数据的读取位置
            String seqCursor = datahubClient.getCursor(Constant.projectName, Constant.topicName, shardId, CursorType.SEQUENCE, seq - 9).getCursor();

            /* SYSTEM_TIME用法示例 */
            //将时间转为时间戳形式
            String time = "2019-07-01 09:00:00";
            SimpleDateFormat simpleDateFormat = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
            Date date = simpleDateFormat.parse(time);
            long timestamp = date.getTime();
            //获取时间time之后的数据读取位置
            String timeCursor = datahubClient.getCursor(Constant.projectName, Constant.topicName, shardId, CursorType.SYSTEM_TIME, timestamp).getCursor();

            System.out.println("get cursor successful");
        } catch (InvalidParameterException e) {
            // invalid parameter, please check your parameter
            e.printStackTrace();
            throw e;
        } catch (AuthorizationFailureException e) {
            // AK error, please check your accessId and accessKey
            e.printStackTrace();
            throw e;
        } catch (ResourceNotFoundException e) {
            // project or topic not found
            e.printStackTrace();
            throw e;
        } catch (SeekOutOfRangeException e){
            // offset invalid ,may be offset has expired
            e.printStackTrace();
            throw e;
        } catch (DatahubClientException e) {
            // other error
            e.printStackTrace();
            throw e;
        } catch (ParseException e) {
            e.printStackTrace();
        }
    }

    public static void main(String[]args){

    }
}