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/** * Licensed to the Apache Software Foundation (ASF) under one * or more contributor license agreements. See the NOTICE file * distributed with this work for additional information * regarding copyright ownership. The ASF licenses this file * to you under the Apache License, Version 2.0 (the * "License"); you may not use this file except in compliance * with the License. You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License 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. */ package org.apache.hive.hplsql.functions; import java.sql.Timestamp; import java.text.SimpleDateFormat; import java.util.Calendar; import java.util.Date; import java.util.TimeZone; import org.apache.commons.lang.StringUtils; import org.apache.hive.hplsql.*; public class FunctionDatetime extends Function { public FunctionDatetime(Exec e) { super(e); } /** * Register functions */ @Override public void register(Function f) { f.map.put("DATE", new FuncCommand() { public void run(HplsqlParser.Expr_func_paramsContext ctx) { date(ctx); } }); f.map.put("FROM_UNIXTIME", new FuncCommand() { public void run(HplsqlParser.Expr_func_paramsContext ctx) { fromUnixtime(ctx); } }); f.map.put("NOW", new FuncCommand() { public void run(HplsqlParser.Expr_func_paramsContext ctx) { now(ctx); } }); f.map.put("TIMESTAMP_ISO", new FuncCommand() { public void run(HplsqlParser.Expr_func_paramsContext ctx) { timestampIso(ctx); } }); f.map.put("TO_TIMESTAMP", new FuncCommand() { public void run(HplsqlParser.Expr_func_paramsContext ctx) { toTimestamp(ctx); } }); f.map.put("UNIX_TIMESTAMP", new FuncCommand() { public void run(HplsqlParser.Expr_func_paramsContext ctx) { unixTimestamp(ctx); } }); f.specMap.put("CURRENT_DATE", new FuncSpecCommand() { public void run(HplsqlParser.Expr_spec_funcContext ctx) { currentDate(ctx); } }); f.specMap.put("CURRENT_TIMESTAMP", new FuncSpecCommand() { public void run(HplsqlParser.Expr_spec_funcContext ctx) { currentTimestamp(ctx); } }); f.specMap.put("SYSDATE", new FuncSpecCommand() { public void run(HplsqlParser.Expr_spec_funcContext ctx) { currentTimestamp(ctx); } }); f.specSqlMap.put("CURRENT_DATE", new FuncSpecCommand() { public void run(HplsqlParser.Expr_spec_funcContext ctx) { currentDateSql(ctx); } }); f.specSqlMap.put("CURRENT_TIMESTAMP", new FuncSpecCommand() { public void run(HplsqlParser.Expr_spec_funcContext ctx) { currentTimestampSql(ctx); } }); } /** * CURRENT_DATE */ public void currentDate(HplsqlParser.Expr_spec_funcContext ctx) { evalVar(currentDate()); } public static Var currentDate() { SimpleDateFormat f = new SimpleDateFormat("yyyy-MM-dd"); String s = f.format(Calendar.getInstance().getTime()); return new Var(Var.Type.DATE, Utils.toDate(s)); } /** * CURRENT_DATE in executable SQL statement */ public void currentDateSql(HplsqlParser.Expr_spec_funcContext ctx) { if (exec.getConnectionType() == Conn.Type.HIVE) { evalString("TO_DATE(FROM_UNIXTIME(UNIX_TIMESTAMP()))"); } else { evalString(exec.getFormattedText(ctx)); } } /** * CURRENT_TIMESTAMP */ public void currentTimestamp(HplsqlParser.Expr_spec_funcContext ctx) { int precision = evalPop(ctx.expr(0), 3).intValue(); evalVar(currentTimestamp(precision)); } public static Var currentTimestamp(int precision) { String format = "yyyy-MM-dd HH:mm:ss"; if (precision > 0 && precision <= 3) { format += "." + StringUtils.repeat("S", precision); } SimpleDateFormat f = new SimpleDateFormat(format); String s = f.format(Calendar.getInstance(TimeZone.getDefault()).getTime()); return new Var(Utils.toTimestamp(s), precision); } /** * CURRENT_TIMESTAMP in executable SQL statement */ public void currentTimestampSql(HplsqlParser.Expr_spec_funcContext ctx) { if (exec.getConnectionType() == Conn.Type.HIVE) { evalString("FROM_UNIXTIME(UNIX_TIMESTAMP())"); } else { evalString(exec.getFormattedText(ctx)); } } /** * DATE function */ void date(HplsqlParser.Expr_func_paramsContext ctx) { if (ctx.func_param().size() != 1) { evalNull(); return; } Var var = new Var(Var.Type.DATE); var.cast(evalPop(ctx.func_param(0).expr())); evalVar(var); } /** * NOW() function (current date and time) */ void now(HplsqlParser.Expr_func_paramsContext ctx) { if (ctx != null) { evalNull(); return; } evalVar(currentTimestamp(3)); } /** * TIMESTAMP_ISO function */ void timestampIso(HplsqlParser.Expr_func_paramsContext ctx) { if (ctx.func_param().size() != 1) { evalNull(); return; } Var var = new Var(Var.Type.TIMESTAMP); var.cast(evalPop(ctx.func_param(0).expr())); evalVar(var); } /** * TO_TIMESTAMP function */ void toTimestamp(HplsqlParser.Expr_func_paramsContext ctx) { if (ctx.func_param().size() != 2) { evalNull(); return; } String value = evalPop(ctx.func_param(0).expr()).toString(); String sqlFormat = evalPop(ctx.func_param(1).expr()).toString(); String format = Utils.convertSqlDatetimeFormat(sqlFormat); try { long timeInMs = new SimpleDateFormat(format).parse(value).getTime(); evalVar(new Var(Var.Type.TIMESTAMP, new Timestamp(timeInMs))); } catch (Exception e) { exec.signal(e); evalNull(); } } /** * FROM_UNIXTIME() function (convert seconds since 1970-01-01 00:00:00 to timestamp) */ void fromUnixtime(HplsqlParser.Expr_func_paramsContext ctx) { int cnt = getParamCount(ctx); if (cnt == 0) { evalNull(); return; } long epoch = evalPop(ctx.func_param(0).expr()).longValue(); String format = "yyyy-MM-dd HH:mm:ss"; if (cnt > 1) { format = evalPop(ctx.func_param(1).expr()).toString(); } evalString(new SimpleDateFormat(format).format(new Date(epoch * 1000))); } /** * UNIX_TIMESTAMP() function (current date and time in seconds since 1970-01-01 00:00:00) */ void unixTimestamp(HplsqlParser.Expr_func_paramsContext ctx) { evalVar(new Var(System.currentTimeMillis() / 1000)); } }