| /* |
| * 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.iotdb.library.string; |
| |
| import org.apache.iotdb.tsfile.read.common.block.column.Column; |
| import org.apache.iotdb.tsfile.read.common.block.column.ColumnBuilder; |
| import org.apache.iotdb.tsfile.utils.Binary; |
| import org.apache.iotdb.udf.api.UDTF; |
| import org.apache.iotdb.udf.api.access.Row; |
| import org.apache.iotdb.udf.api.collector.PointCollector; |
| import org.apache.iotdb.udf.api.customizer.config.UDTFConfigurations; |
| import org.apache.iotdb.udf.api.customizer.parameter.UDFParameterValidator; |
| import org.apache.iotdb.udf.api.customizer.parameter.UDFParameters; |
| import org.apache.iotdb.udf.api.customizer.strategy.MappableRowByRowAccessStrategy; |
| import org.apache.iotdb.udf.api.type.Type; |
| |
| import java.io.IOException; |
| |
| /** This function does limited times of replacement of substring from an input series. */ |
| public class UDTFStrReplace implements UDTF { |
| |
| private String target; |
| private String replace; |
| private int limit; |
| private int offset; |
| private boolean reverse; |
| |
| @Override |
| public void validate(UDFParameterValidator validator) throws Exception { |
| validator |
| .validateInputSeriesNumber(1) |
| .validateInputSeriesDataType(0, Type.TEXT) |
| .validate( |
| target -> ((String) target).length() > 0, |
| "target should not be empty", |
| validator.getParameters().getString("target")) |
| .validate( |
| limit -> (int) limit >= -1, |
| "limit has to be -1 for replacing all matches or non-negative integers for limited" |
| + " times.", |
| validator.getParameters().getIntOrDefault("limit", -1)) |
| .validate( |
| offset -> (int) offset >= 0, |
| "offset has to be non-negative to skip first several matches.", |
| validator.getParameters().getIntOrDefault("offset", 0)); |
| } |
| |
| @Override |
| public void beforeStart(UDFParameters udfParameters, UDTFConfigurations udtfConfigurations) |
| throws Exception { |
| target = udfParameters.getString("target"); |
| replace = udfParameters.getString("replace"); |
| limit = udfParameters.getIntOrDefault("limit", -1); |
| offset = udfParameters.getIntOrDefault("offset", 0); |
| reverse = udfParameters.getBooleanOrDefault("reverse", false); |
| udtfConfigurations |
| .setAccessStrategy(new MappableRowByRowAccessStrategy()) |
| .setOutputDataType(Type.TEXT); |
| } |
| |
| @Override |
| public void transform(Row row, PointCollector collector) throws Exception { |
| String origin = row.getString(0); |
| String result = getResult(origin); |
| collector.putString(row.getTime(), result); |
| } |
| |
| @Override |
| public Object transform(Row row) throws IOException { |
| if (row.isNull(0)) { |
| return null; |
| } |
| String str = row.getString(0); |
| |
| return getResult(str); |
| } |
| |
| @Override |
| public void transform(Column[] columns, ColumnBuilder builder) throws Exception { |
| Binary[] inputs = columns[0].getBinaries(); |
| boolean[] isNulls = columns[0].isNull(); |
| |
| int count = columns[0].getPositionCount(); |
| for (int i = 0; i < count; i++) { |
| if (isNulls[i]) { |
| builder.appendNull(); |
| } else { |
| String str = inputs[i].toString(); |
| builder.writeBinary(new Binary(getResult(str).getBytes())); |
| } |
| } |
| } |
| |
| private String getResult(String origin) { |
| String result; |
| if (reverse) { |
| int endIndex = origin.length(); |
| int count = 0; |
| while (count < offset) { |
| int matchIndex = origin.lastIndexOf(target, endIndex - 1); |
| if (matchIndex == -1) { |
| break; |
| } else { |
| endIndex = matchIndex; |
| count++; |
| } |
| } |
| // no enough matches to skip |
| if (count < offset) { |
| endIndex = 0; |
| } |
| String suffix = origin.substring(endIndex); |
| while (count < offset + limit) { |
| int matchIndex = origin.lastIndexOf(target, endIndex - 1); |
| if (matchIndex == -1) { |
| break; |
| } else { |
| endIndex = matchIndex; |
| count++; |
| } |
| } |
| // replace all left matches |
| if (limit == -1 || count < offset + limit) { |
| endIndex = 0; |
| } |
| String prefix = origin.substring(0, endIndex); |
| result = |
| prefix |
| .concat( |
| origin |
| .substring(endIndex, origin.length() - suffix.length()) |
| .replace(target, replace)) |
| .concat(suffix); |
| } else { |
| int fromIndex = 0; |
| int count = 0; |
| while (count < offset) { |
| int matchIndex = origin.indexOf(target, fromIndex); |
| if (matchIndex == -1) { |
| break; |
| } else { |
| fromIndex = matchIndex + target.length(); |
| count++; |
| } |
| } |
| // no enough matches to skip |
| if (count < offset) { |
| fromIndex = origin.length(); |
| } |
| String prefix = origin.substring(0, fromIndex); |
| while (count < offset + limit) { |
| int matchIndex = origin.indexOf(target, fromIndex); |
| if (matchIndex == -1) { |
| break; |
| } else { |
| fromIndex = matchIndex + target.length(); |
| count++; |
| } |
| } |
| // replace all left matches |
| if (limit == -1 || count < offset + limit) { |
| fromIndex = origin.length(); |
| } |
| String suffix = origin.substring(fromIndex); |
| result = |
| prefix |
| .concat(origin.substring(prefix.length(), fromIndex).replace(target, replace)) |
| .concat(suffix); |
| } |
| |
| return result; |
| } |
| } |