| /* |
| * 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.analytics.value; |
| |
| import java.util.function.Consumer; |
| |
| import org.apache.solr.analytics.facet.compare.ExpressionComparator; |
| import org.apache.solr.analytics.value.constant.ConstantStringValue; |
| |
| /** |
| * A single-valued analytics value that can be represented as a string. |
| * <p> |
| * The back-end production of the value can change inbetween calls to {@link #getString()} and {@link #exists()}, |
| * resulting in different values on each call. |
| */ |
| public interface StringValue extends StringValueStream, AnalyticsValue { |
| /** |
| * Get the String representation of the current value. |
| * <p> |
| * NOTE: The value returned is not valid unless calling {@link #exists()} afterwards returns {@code TRUE}. |
| * |
| * @return the current value |
| */ |
| String getString(); |
| |
| /** |
| * An interface that represents all of the types a {@link StringValue} should be able to cast to. |
| */ |
| public static interface CastingStringValue extends StringValue, ComparableValue {} |
| |
| /** |
| * An abstract base for {@link CastingStringValue} that automatically casts to all types if {@link #getString()} and {@link #exists()} are implemented. |
| */ |
| public static abstract class AbstractStringValue implements CastingStringValue { |
| @Override |
| public String getObject() { |
| return getString(); |
| } |
| @Override |
| public void streamStrings(Consumer<String> func) { |
| String val = getString(); |
| if (exists()) { |
| func.accept(val); |
| } |
| } |
| @Override |
| public void streamObjects(Consumer<Object> func) { |
| Object val = getObject(); |
| if (exists()) { |
| func.accept(val); |
| } |
| } |
| @Override |
| public AnalyticsValue convertToConstant() { |
| if (getExpressionType().equals(ExpressionType.CONST)) { |
| return new ConstantStringValue(getString()); |
| } |
| return this; |
| } |
| @Override |
| public ExpressionComparator<String> getObjectComparator(String expression) { |
| return new ExpressionComparator<>(expression); |
| } |
| } |
| } |