（1）引入依赖模块

public static void main(String[] args) throws SQLException, ClassNotFoundException {    //1. 加载驱动类：    Class.forName("com.webank.wedatasphere.linkis.ujes.jdbc.UJESSQLDriver");    //2. 获得连接：jdbc:linkis://gatewayIP:gatewayPort   帐号和密码对应前端的帐号密码    Connection connection =  DriverManager.getConnection("jdbc:linkis://127.0.0.1:9001","username","password");    //3. 创建statement 和执行查询    Statement st= connection.createStatement();    ResultSet rs=st.executeQuery("show tables");    //4.处理数据库的返回结果(使用ResultSet类)    while (rs.next()) {        ResultSetMetaData metaData = rs.getMetaData();        for (int i = 1; i             System.out.print(metaData.getColumnName(i) + ":" +metaData.getColumnTypeName(i)+": "+ rs.getObject(i) + "    ");        }        System.out.println();    }    //关闭资源    rs.close();    st.close();    connection.close();}

static {    try {        DriverManager.registerDriver(new UJESSQLDriver());    } catch (SQLException e) {        Logger logger = LoggerFactory.getLogger(UJESSQLDriver.class);        logger.info("Load driver failed",e);    }}

conn = (UJESSQLConnection) DriverManager  .getConnection("jdbc:linkis://hostname:port","username","password")

override def connect(url: String, info: Properties): Connection = if(acceptsURL(url)) {  val props = if(info != null) info else newProperties  props.putAll(parseURL(url))  val ujesClient =UJESClientFactory.getUJESClient(props)  new UJESSQLConnection(ujesClient, props)} else throw newUJESSQLException(UJESSQLErrorCode.BAD_URL, "bad url: " + url)
private def parseURL(url: String): Properties= {  val props = new Properties  //add an entry to get url  props.setProperty("URL", url)  url match {    case URL_REGEX(host, port, db, params)=>      if(StringUtils.isNotBlank(host))props.setProperty(HOST, host)      if(StringUtils.isNotBlank(port))props.setProperty(PORT, port.substring(1))      if(StringUtils.isNotBlank(db)&& db.length > 1) props.setProperty(DB_NAME, db.substring(1))      if(StringUtils.isNotBlank(params)&& params.length > 1) {        val _params = params.substring(1)        val kvs =_params.split(PARAM_SPLIT).map(_.split(KV_SPLIT)).filter {          case Array(USER, value) =>            props.setProperty(USER, value)            false          case Array(PASSWORD, value) =>            props.setProperty(PASSWORD,value)            false          case Array(key, _) =>            if(StringUtils.isBlank(key)) {              throw newUJESSQLException(UJESSQLErrorCode.BAD_URL, "bad url for params: " +url)            } else true          case _ => throw newUJESSQLException(UJESSQLErrorCode.BAD_URL, "bad url for params: " +url)        }        props.setProperty(PARAMS,kvs.map(_.mkString(KV_SPLIT)).mkString(PARAM_SPLIT))      }    case _ => throw newUJESSQLException(UJESSQLErrorCode.BAD_URL, "bad url: " + url)  }  props}

def getUJESClient(props: Properties):UJESClient = {  val host = props.getProperty(HOST)  val port = props.getProperty(PORT)  val serverUrl = if(StringUtils.isNotBlank(port))s"http://$host:$port" else "http://" + host  if(ujesClients.containsKey(serverUrl))ujesClients.get(serverUrl)  else serverUrl.intern synchronized {    if(ujesClients.containsKey(serverUrl))return ujesClients.get(serverUrl)    val ujesClient =createUJESClient(serverUrl, props)    ujesClients.put(serverUrl, ujesClient)    ujesClient  }}

//获取执行对象UJESSQLStatementstatement = (UJESSQLStatementCon) conn.createStatement;//获取预执行对象UJESSQLPrepareStatementpreStatement = (UJESSQLPrepareStatement) conn.prePareStatement;

override defexecute(sql: String): Boolean = throwWhenClosed {  var parsedSQL = sql  //预执行hook，转换不支持的sql语句 JDBCDriverPreExecutionHook.getPreExecutionHooks.foreach{    preExecution =>      parsedSQL = preExecution.callPreExecutionHook(parsedSQL)  }  //获取linkis的job执行器，创建用于执行的action任务 val action =JobExecuteAction.builder().setEngineType(EngineType.SPARK).addExecuteCode(parsedSQL)   .setCreator(ujesSQLConnection.creator).setUser(ujesSQLConnection.user) if(ujesSQLConnection.variableMap.nonEmpty)action.setVariableMap(JavaConversions.mapAsJavaMap(ujesSQLConnection.variableMap))  //提交SQL任务到ujes客户端执行  jobExecuteResult =ujesSQLConnection.ujesClient.execute(action.build())  queryEnd = false  //job状态检测  var status =ujesSQLConnection.ujesClient.status(jobExecuteResult) val atMost = if(queryTimeout > 0) Duration(queryTimeout,TimeUnit.MILLISECONDS) else Duration.Inf  if(!status.isCompleted)Utils.tryThrow{    Utils.waitUntil(() =>{      status =ujesSQLConnection.ujesClient.status(jobExecuteResult)      status.isCompleted ||closed    }, atMost, 100, 10000)  } {    case t: TimeoutException=>      if(queryTimeout >0) clearQuery()      newUJESSQLException(UJESSQLErrorCode.QUERY_TIMEOUT, "query has beentimeout!").initCause(t)    case t => t  }  if(!closed) {    var jobInfo =ujesSQLConnection.ujesClient.getJobInfo(jobExecuteResult)    if(status.isFailed)throw new ErrorException(jobInfo.getRequestPersistTask.getErrCode,jobInfo.getRequestPersistTask.getErrDesc)    val jobInfoStatus =jobInfo.getJobStatus   if(!jobInfoStatus.equals("Succeed")) Utils.tryThrow{      Utils.waitUntil(()=> {        jobInfo = ujesSQLConnection.ujesClient.getJobInfo(jobExecuteResult)        val state =jobInfo.getJobStatus match{          case"Failed" | "Cancelled" | "Timeout" |"Succeed" => true          case _ => false        }        state || closed      }, atMost, 100, 10000)    } {      case t:TimeoutException =>        if(queryTimeout >0) clearQuery()        newUJESSQLException(UJESSQLErrorCode.QUERY_TIMEOUT, "query has beentimeout!").initCause(t)      case t => t    }    //获取结果集    val resultSetList =jobInfo.getResultSetList(ujesSQLConnection.ujesClient)    queryEnd = true    if(resultSetList !=null) {      resultSet = newUJESSQLResultSet(resultSetList, this, maxRows, fetchSize)      true    } else false  } else throw newUJESSQLException(UJESSQLErrorCode.STATEMENT_CLOSED, "Statement isclosed.")}

private def init(): Unit = {  resultSetResultInit()  metaDataInit()  resultSetInit()} private def resultSetResultInit(): Unit = {  if (path == null) path =getResultSetPath(resultSetList)  val user =connection.getProps.getProperty("user")  if(StringUtils.isNotBlank(path)){    val resultAction =ResultSetAction.builder.setUser(user).setPath(path).build()    resultSetResult =connection.ujesClient.resultSet(resultAction)  }} private def metaDataInit(): Unit = {  if ( null ==resultSetResult ){    return  }  metaData =resultSetResult.getMetadata.asInstanceOf[util.List[util.Map[String, String]]]  for(cursor 1 tometaData.size()){    val col =metaData.get(cursor - 1)   resultSetMetaData.setColumnNameProperties(cursor,col.get("columnName"))   resultSetMetaData.setDataTypeProperties(cursor,col.get("dataType"))   resultSetMetaData.setCommentPropreties(cursor,col.get("comment"))  }} private def resultSetInit(): Unit = {  if ( null ==resultSetResult ){    return  }  resultSetRow =resultSetResult.getFileContent.asInstanceOf[util.ArrayList[util.ArrayList[String]]]}

override def next(): Boolean = {  if(metaData == null)init()  currentRowCursor += 1  if(null == resultSetRow ||currentRowCursor > resultSetRow.size()-1) false  else{   updateCurrentRow(currentRowCursor)    true  }}

override def getString(columnIndex: Int): String = {  val any  = getColumnValue(columnIndex)  if(wasNull()) {    throw newUJESSQLException(UJESSQLErrorCode.RESULTSET_ROWERROR, "Type is null")  }else{    any.asInstanceOf[String]  }}

public enum UJESSQLErrorCode {  BAD_URL(80000,"badurl"),  NOSUPPORT_DRIVER(80001,"this method not supported in driver"),  NOSUPPORT_CONNECTION(80002,"this method not supported in connection"),  NOSUPPORT_STATEMENT(80003,"this method not supported instatement"),  CONNECTION_CLOSED(80004,"Connection is closed!"),  STATEMENT_CLOSED(80005,"statement is closed!"),  SCHEMA_EMPTY(80006,"schemais empty!"),  SCHEMA_FAILED(80007,"Get schema failed!"),  QUERY_TIMEOUT(80008,"query has been timeout!"),  FILETYPE_ERROR(80009,"file type error"),  METADATATYPE_ERROR(80010,"metadata type error"),  NOSUPPORT_METADATA(80011, "thismethod not supported in DatabaseMetaData"),  NOPERMITION(80012,"This user has no permission to read thisfile!"),  PARAMS_NOT_FOUND(80013,"Parameter not found"),  ERRORINFO_FROM_JOBINFO(80014,"get errorinfo from jobInfo"),  RESULTSET_ROWERROR(80015,"rowmessage error"),  NOSUPPORT_RESULTSET(80016,"this method not supported inresultSet"),  RESULTSET_NULL(80017,"resultset is null,try to run next() firstlyto init ResultSet and MetaData"),  PREPARESTATEMENT_TYPEERROR(80018,"parameter type error"),  METADATA_EMPTY(80019,"data is empty")  ;  private String msg;  private int code;
  UJESSQLErrorCode(intcode,String msg) {      this.code = code;      this.msg = msg;  }
  public String getMsg() {      return msg;  }
  public int getCode() {      return code;  }}