| /* |
| * 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.solr.update.processor; |
| |
| import java.lang.invoke.MethodHandles; |
| import java.util.Collection; |
| import java.util.function.Function; |
| |
| import org.apache.solr.common.SolrInputField; |
| |
| import org.slf4j.Logger; |
| import org.slf4j.LoggerFactory; |
| |
| /** |
| * Abstract subclass of FieldMutatingUpdateProcessor for implementing |
| * UpdateProcessors that will mutate all individual values of a selected |
| * field independently |
| * |
| * @see FieldMutatingUpdateProcessorFactory |
| */ |
| public abstract class FieldValueMutatingUpdateProcessor |
| extends FieldMutatingUpdateProcessor { |
| |
| private static final Logger log = LoggerFactory.getLogger(MethodHandles.lookup().lookupClass()); |
| |
| |
| public static final Object DELETE_VALUE_SINGLETON = new Object() { |
| @Override |
| public String toString() { |
| return "!!Singleton Object Triggering Value Deletion!!"; |
| } |
| }; |
| |
| public FieldValueMutatingUpdateProcessor(FieldNameSelector selector, |
| UpdateRequestProcessor next) { |
| super(selector, next); |
| } |
| |
| /** |
| * Mutates individual values of a field as needed, or returns the original |
| * value. |
| * |
| * @param src a value from a matched field which should be mutated |
| * @return the value to use as a replacement for src, or |
| * <code>DELETE_VALUE_SINGLETON</code> to indicate that the value |
| * should be removed completely. |
| * @see #DELETE_VALUE_SINGLETON |
| */ |
| protected abstract Object mutateValue(final Object src); |
| |
| @Override |
| protected final SolrInputField mutate(final SolrInputField src) { |
| Collection<Object> values = src.getValues(); |
| if(values == null) return src;//don't mutate |
| SolrInputField result = new SolrInputField(src.getName()); |
| for (final Object srcVal : values) { |
| final Object destVal = mutateValue(srcVal); |
| if (DELETE_VALUE_SINGLETON == destVal) { |
| /* NOOP */ |
| if (log.isDebugEnabled()) { |
| log.debug("removing value from field '{}': {}", |
| src.getName(), srcVal); |
| } |
| } else { |
| if (destVal != srcVal) { |
| if (log.isDebugEnabled()) { |
| log.debug("replace value from field '{}': {} with {}", |
| new Object[]{src.getName(), srcVal, destVal}); |
| } |
| } |
| result.addValue(destVal); |
| } |
| } |
| return 0 == result.getValueCount() ? null : result; |
| } |
| |
| public static FieldValueMutatingUpdateProcessor valueMutator(FieldNameSelector selector, |
| UpdateRequestProcessor next, |
| Function<Object, Object> fun) { |
| return new FieldValueMutatingUpdateProcessor(selector, next) { |
| @Override |
| protected Object mutateValue(Object src) { |
| return fun.apply(src); |
| } |
| }; |
| } |
| } |
| |