| /* |
| * 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.druid.query.extraction; |
| |
| import com.fasterxml.jackson.annotation.JsonCreator; |
| import com.fasterxml.jackson.annotation.JsonProperty; |
| import com.google.common.base.Joiner; |
| import com.google.common.base.Preconditions; |
| import com.google.common.primitives.Bytes; |
| |
| import javax.annotation.Nullable; |
| import java.util.Arrays; |
| |
| public class CascadeExtractionFn implements ExtractionFn |
| { |
| private final ExtractionFn[] extractionFns; |
| private final ChainedExtractionFn chainedExtractionFn; |
| private final ChainedExtractionFn DEFAULT_CHAINED_EXTRACTION_FN = new ChainedExtractionFn( |
| new ExtractionFn() |
| { |
| @Override |
| public byte[] getCacheKey() |
| { |
| return new byte[0]; |
| } |
| |
| @Nullable |
| @Override |
| public String apply(@Nullable Object value) |
| { |
| return null; |
| } |
| |
| @Nullable |
| @Override |
| public String apply(@Nullable String value) |
| { |
| return null; |
| } |
| |
| @Override |
| public String apply(long value) |
| { |
| return null; |
| } |
| |
| @Override |
| public boolean preservesOrdering() |
| { |
| return false; |
| } |
| |
| @Override |
| public ExtractionType getExtractionType() |
| { |
| return ExtractionType.MANY_TO_ONE; |
| } |
| |
| @Override |
| public String toString() |
| { |
| return "nullExtractionFn{}"; |
| } |
| }, |
| null |
| ); |
| |
| @JsonCreator |
| public CascadeExtractionFn( |
| @JsonProperty("extractionFns") ExtractionFn[] extractionFn |
| ) |
| { |
| Preconditions.checkArgument(extractionFn != null, "extractionFns should not be null"); |
| this.extractionFns = extractionFn; |
| if (extractionFns.length == 0) { |
| this.chainedExtractionFn = DEFAULT_CHAINED_EXTRACTION_FN; |
| } else { |
| ChainedExtractionFn root = null; |
| for (ExtractionFn fn : extractionFn) { |
| Preconditions.checkArgument(fn != null, "empty function is not allowed"); |
| root = new ChainedExtractionFn(fn, root); |
| } |
| this.chainedExtractionFn = root; |
| } |
| } |
| |
| @JsonProperty |
| public ExtractionFn[] getExtractionFns() |
| { |
| return extractionFns; |
| } |
| |
| @Override |
| public byte[] getCacheKey() |
| { |
| byte[] cacheKey = new byte[]{ExtractionCacheHelper.CACHE_TYPE_ID_CASCADE}; |
| |
| return Bytes.concat(cacheKey, chainedExtractionFn.getCacheKey()); |
| } |
| |
| @Override |
| @Nullable |
| public String apply(@Nullable Object value) |
| { |
| return chainedExtractionFn.apply(value); |
| } |
| |
| @Override |
| @Nullable |
| public String apply(@Nullable String value) |
| { |
| return chainedExtractionFn.apply(value); |
| } |
| |
| @Override |
| public String apply(long value) |
| { |
| return chainedExtractionFn.apply(value); |
| } |
| |
| @Override |
| public boolean preservesOrdering() |
| { |
| return chainedExtractionFn.preservesOrdering(); |
| } |
| |
| @Override |
| public ExtractionType getExtractionType() |
| { |
| return chainedExtractionFn.getExtractionType(); |
| } |
| |
| @Override |
| public boolean equals(Object o) |
| { |
| if (this == o) { |
| return true; |
| } |
| if (o == null || getClass() != o.getClass()) { |
| return false; |
| } |
| |
| CascadeExtractionFn that = (CascadeExtractionFn) o; |
| |
| if (!Arrays.equals(extractionFns, that.extractionFns)) { |
| return false; |
| } |
| if (!chainedExtractionFn.equals(that.chainedExtractionFn)) { |
| return false; |
| } |
| |
| return true; |
| } |
| |
| @Override |
| public int hashCode() |
| { |
| return chainedExtractionFn.hashCode(); |
| } |
| |
| @Override |
| public String toString() |
| { |
| return "CascadeExtractionFn{extractionFns=[" + chainedExtractionFn + "]}"; |
| } |
| |
| private static class ChainedExtractionFn |
| { |
| private final ExtractionFn fn; |
| private final ChainedExtractionFn child; |
| |
| public ChainedExtractionFn(ExtractionFn fn, ChainedExtractionFn child) |
| { |
| this.fn = fn; |
| this.child = child; |
| } |
| |
| public byte[] getCacheKey() |
| { |
| byte[] fnCacheKey = fn.getCacheKey(); |
| |
| return (child != null) ? Bytes.concat(fnCacheKey, child.getCacheKey()) : fnCacheKey; |
| } |
| |
| @Nullable |
| public String apply(@Nullable Object value) |
| { |
| return fn.apply((child != null) ? child.apply(value) : value); |
| } |
| |
| @Nullable |
| public String apply(@Nullable String value) |
| { |
| return fn.apply((child != null) ? child.apply(value) : value); |
| } |
| |
| public String apply(long value) |
| { |
| return fn.apply((child != null) ? child.apply(value) : value); |
| } |
| |
| public boolean preservesOrdering() |
| { |
| boolean childPreservesOrdering = (child == null) || child.preservesOrdering(); |
| return fn.preservesOrdering() && childPreservesOrdering; |
| } |
| |
| public ExtractionType getExtractionType() |
| { |
| if (child != null && child.getExtractionType() == ExtractionType.MANY_TO_ONE) { |
| return ExtractionType.MANY_TO_ONE; |
| } else { |
| return fn.getExtractionType(); |
| } |
| } |
| |
| @Override |
| public boolean equals(Object o) |
| { |
| if (this == o) { |
| return true; |
| } |
| if (o == null || getClass() != o.getClass()) { |
| return false; |
| } |
| |
| ChainedExtractionFn that = (ChainedExtractionFn) o; |
| |
| if (!fn.equals(that.fn)) { |
| return false; |
| } |
| if (child != null && !child.equals(that.child)) { |
| return false; |
| } |
| |
| return true; |
| } |
| |
| @Override |
| public int hashCode() |
| { |
| int result = fn.hashCode(); |
| if (child != null) { |
| result = 31 * result + child.hashCode(); |
| } |
| return result; |
| } |
| |
| @Override |
| public String toString() |
| { |
| return (child != null) |
| ? Joiner.on(",").join(child.toString(), fn.toString()) |
| : fn.toString(); |
| } |
| } |
| } |