muyangye commented on code in PR #1858: URL: https://github.com/apache/streampipes/pull/1858#discussion_r1313413443
########## streampipes-extensions/streampipes-processors-transformation-jvm/src/main/java/org/apache/streampipes/processors/transformation/jvm/processor/round/RoundProcessor.java: ########## @@ -0,0 +1,85 @@ +/* + * 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.streampipes.processors.transformation.jvm.processor.round; + +import org.apache.streampipes.commons.exceptions.SpRuntimeException; +import org.apache.streampipes.extensions.api.pe.context.EventProcessorRuntimeContext; +import org.apache.streampipes.extensions.api.pe.routing.SpOutputCollector; +import org.apache.streampipes.model.DataProcessorType; +import org.apache.streampipes.model.graph.DataProcessorDescription; +import org.apache.streampipes.model.runtime.Event; +import org.apache.streampipes.model.schema.PropertyScope; +import org.apache.streampipes.sdk.builder.ProcessingElementBuilder; +import org.apache.streampipes.sdk.builder.StreamRequirementsBuilder; +import org.apache.streampipes.sdk.helpers.EpRequirements; +import org.apache.streampipes.sdk.helpers.Labels; +import org.apache.streampipes.sdk.helpers.Locales; +import org.apache.streampipes.sdk.helpers.OutputStrategies; +import org.apache.streampipes.sdk.utils.Assets; +import org.apache.streampipes.wrapper.params.compat.ProcessorParams; +import org.apache.streampipes.wrapper.standalone.StreamPipesDataProcessor; + +import java.math.BigDecimal; +import java.math.RoundingMode; +import java.util.List; + +public class RoundProcessor extends StreamPipesDataProcessor { + private List<String> fieldsToBeRounded; + private int numDigits; + + private static final String FIELDS = "fields"; + private static final String NUM_DIGITS = "num-digits"; + + @Override + public DataProcessorDescription declareModel() { + return ProcessingElementBuilder + .create("org.apache.streampipes.processors.transformation.jvm.round") + .category(DataProcessorType.TRANSFORM) + .withLocales(Locales.EN) + .withAssets(Assets.DOCUMENTATION, Assets.ICON) + .requiredStream(StreamRequirementsBuilder + .create() + .requiredPropertyWithNaryMapping(EpRequirements.numberReq(), Labels.withId(FIELDS), PropertyScope.NONE) + .build()) + .requiredIntegerParameter(Labels.withId(NUM_DIGITS)) + .outputStrategy(OutputStrategies.keep()) + .build(); + } + + @Override + public void onInvocation(ProcessorParams parameters, SpOutputCollector spOutputCollector, + EventProcessorRuntimeContext runtimeContext) throws SpRuntimeException { + fieldsToBeRounded = parameters.extractor().mappingPropertyValues(FIELDS); + numDigits = parameters.extractor().singleValueParameter(NUM_DIGITS, Integer.class); + } + + @Override + public void onEvent(Event event, SpOutputCollector collector) throws SpRuntimeException { + for (String fieldToBeRounded : fieldsToBeRounded) { + double value = event.getFieldBySelector(fieldToBeRounded).getAsPrimitive().getAsDouble(); + double roundedValue = BigDecimal.valueOf(value).setScale(numDigits, RoundingMode.HALF_UP).doubleValue(); Review Comment: For sure, I will support all the rounding modes specified [here](https://docs.oracle.com/javase/8/docs/api/java/math/RoundingMode.html). Should we also support custom number to round up (e.g. 3 to round up means 1.3 will be rounded to 2)? I believe this is somewhat unnecessary because the user can just apply some mathematical transformations to achieve this. What do you think? -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
