| /* |
| * 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.tinkerpop.gremlin.util.function; |
| |
| import org.apache.tinkerpop.gremlin.jsr223.GremlinScriptEngine; |
| |
| import java.io.Serializable; |
| import java.util.Comparator; |
| import java.util.function.BiFunction; |
| import java.util.function.BinaryOperator; |
| import java.util.function.Consumer; |
| import java.util.function.Function; |
| import java.util.function.Predicate; |
| import java.util.function.Supplier; |
| import java.util.function.UnaryOperator; |
| |
| /** |
| * Provides a way to serialize string lambdas as scripts which can be evaluated by a {@link GremlinScriptEngine}. |
| * |
| * @author Marko A. Rodriguez (http://markorodriguez.com) |
| * @author Stephen Mallette (http://stephen.genoprime.com) |
| */ |
| public interface Lambda extends Serializable { |
| |
| public String getLambdaScript(); |
| |
| public String getLambdaLanguage(); |
| |
| public int getLambdaArguments(); |
| |
| public abstract static class AbstractLambda implements Lambda { |
| private final String lambdaSource; |
| private final String lambdaLanguage; |
| private final int lambdaArguments; |
| |
| private AbstractLambda(final String lambdaSource, final String lambdaLanguage, final int lambdaArguments) { |
| this.lambdaSource = lambdaSource; |
| this.lambdaLanguage = lambdaLanguage; |
| this.lambdaArguments = lambdaArguments; |
| } |
| |
| @Override |
| public String getLambdaScript() { |
| return this.lambdaSource; |
| } |
| |
| @Override |
| public String getLambdaLanguage() { |
| return this.lambdaLanguage; |
| } |
| |
| @Override |
| public int getLambdaArguments() { |
| return this.lambdaArguments; |
| } |
| |
| @Override |
| public String toString() { |
| return "lambda[" + this.lambdaSource + "]"; |
| } |
| |
| @Override |
| public int hashCode() { |
| return this.lambdaSource.hashCode() + this.lambdaLanguage.hashCode() + this.lambdaArguments; |
| } |
| |
| @Override |
| public boolean equals(final Object object) { |
| return object instanceof Lambda && |
| ((Lambda) object).getLambdaArguments() == this.getLambdaArguments() && |
| ((Lambda) object).getLambdaScript().equals(this.lambdaSource) && |
| ((Lambda) object).getLambdaLanguage().equals(this.lambdaLanguage); |
| } |
| } |
| |
| public static class UnknownArgLambda extends AbstractLambda { |
| |
| public UnknownArgLambda(final String lambdaSource, final String lambdaLanguage, final int lambdaArguments) { |
| super(lambdaSource, lambdaLanguage, lambdaArguments); |
| } |
| } |
| |
| public static class ZeroArgLambda<A> extends AbstractLambda implements Supplier<A> { |
| |
| public ZeroArgLambda(final String lambdaSource, final String lambdaLanguage) { |
| super(lambdaSource, lambdaLanguage, 0); |
| } |
| |
| @Override |
| public A get() { |
| return null; |
| } |
| |
| } |
| |
| public static class UnaryLambda<A> extends OneArgLambda<A, A> implements UnaryOperator<A> { |
| public UnaryLambda(final String lambdaSource, final String lambdaLanguage) { |
| super(lambdaSource, lambdaLanguage); |
| } |
| } |
| |
| public static class OneArgLambda<A, B> extends AbstractLambda implements Function<A, B>, Predicate<A>, Consumer<A> { |
| |
| public OneArgLambda(final String lambdaSource, final String lambdaLanguage) { |
| super(lambdaSource, lambdaLanguage, 1); |
| } |
| |
| @Override |
| public B apply(final A a) { |
| return null; |
| } |
| |
| @Override |
| public boolean test(final A a) { |
| return false; |
| } |
| |
| @Override |
| public void accept(final A a) { |
| |
| } |
| } |
| |
| public static class BinaryLambda<A> extends TwoArgLambda<A, A, A> implements BinaryOperator<A> { |
| public BinaryLambda(final String lambdaSource, final String lambdaLanguage) { |
| super(lambdaSource, lambdaLanguage); |
| } |
| } |
| |
| public static class TwoArgLambda<A, B, C> extends AbstractLambda implements BiFunction<A, B, C>, Comparator<A> { |
| |
| public TwoArgLambda(final String lambdaSource, final String lambdaLanguage) { |
| super(lambdaSource, lambdaLanguage, 2); |
| } |
| |
| @Override |
| public C apply(final A a, final B b) { |
| return null; |
| } |
| |
| |
| @Override |
| public int compare(final A first, final A second) { |
| return 0; |
| } |
| } |
| |
| /// |
| |
| public static String DEFAULT_LAMBDA_LANGUAGE = "gremlin-groovy"; |
| |
| public static <A> UnaryOperator<A> unaryOperator(final String lambdaSource, final String lambdaLanguage) { |
| return new UnaryLambda<>(lambdaSource, lambdaLanguage); |
| } |
| |
| public static <A, B> Function<A, B> function(final String lambdaSource, final String lambdaLanguage) { |
| return new OneArgLambda<>(lambdaSource, lambdaLanguage); |
| } |
| |
| public static <A> Predicate<A> predicate(final String lambdaSource, final String lambdaLanguage) { |
| return new OneArgLambda<>(lambdaSource, lambdaLanguage); |
| } |
| |
| public static <A> Consumer<A> consumer(final String lambdaSource, final String lambdaLanguage) { |
| return new OneArgLambda<>(lambdaSource, lambdaLanguage); |
| } |
| |
| public static <A> Supplier<A> supplier(final String lambdaSource, final String lambdaLanguage) { |
| return new ZeroArgLambda<>(lambdaSource, lambdaLanguage); |
| } |
| |
| public static <A> Comparator<A> comparator(final String lambdaSource, final String lambdaLanguage) { |
| return new TwoArgLambda<>(lambdaSource, lambdaLanguage); |
| } |
| |
| public static <A, B, C> BiFunction<A, B, C> biFunction(final String lambdaSource, final String lambdaLanguage) { |
| return new TwoArgLambda<>(lambdaSource, lambdaLanguage); |
| } |
| |
| // |
| |
| public static <A> UnaryOperator<A> unaryOperator(final String lambdaSource) { |
| return new UnaryLambda<>(lambdaSource, DEFAULT_LAMBDA_LANGUAGE); |
| } |
| |
| public static <A, B> Function<A, B> function(final String lambdaSource) { |
| return new OneArgLambda<>(lambdaSource, DEFAULT_LAMBDA_LANGUAGE); |
| } |
| |
| public static <A> Predicate<A> predicate(final String lambdaSource) { |
| return new OneArgLambda<>(lambdaSource, DEFAULT_LAMBDA_LANGUAGE); |
| } |
| |
| public static <A> Consumer<A> consumer(final String lambdaSource) { |
| return new OneArgLambda<>(lambdaSource, DEFAULT_LAMBDA_LANGUAGE); |
| } |
| |
| public static <A> Supplier<A> supplier(final String lambdaSource) { |
| return new ZeroArgLambda<>(lambdaSource, DEFAULT_LAMBDA_LANGUAGE); |
| } |
| |
| public static <A> Comparator<A> comparator(final String lambdaSource) { |
| return new TwoArgLambda<>(lambdaSource, DEFAULT_LAMBDA_LANGUAGE); |
| } |
| |
| public static <A, B, C> BiFunction<A, B, C> biFunction(final String lambdaSource) { |
| return new TwoArgLambda<>(lambdaSource, DEFAULT_LAMBDA_LANGUAGE); |
| } |
| |
| public static <A> BinaryOperator<A> binaryOperator(final String lambdaSource) { |
| return new BinaryLambda<>(lambdaSource, DEFAULT_LAMBDA_LANGUAGE); |
| } |
| } |