Java tutorial
/* * Copyright 2015 Lithium Technologies, Inc. * * Licensed 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 com.lithium.flow.config.parsers; import static com.google.common.base.Preconditions.checkNotNull; import com.lithium.flow.config.ConfigBuilder; import com.lithium.flow.config.ConfigParser; import javax.annotation.Nonnull; import com.google.common.base.Joiner; import com.google.common.base.Splitter; import com.google.common.collect.Iterables; /** * @author Matt Ayres */ public class SubtractConfigParser implements ConfigParser { @Override public boolean parseLine(@Nonnull String line, @Nonnull ConfigBuilder builder) { checkNotNull(line); checkNotNull(builder); int index = line.indexOf("-="); if (index > -1 && index < line.indexOf("=")) { String key = line.substring(0, index).trim(); final String value = line.substring(index + 2).trim(); String oldValue = builder.getString(key); if (oldValue != null) { builder.setString(key, Joiner.on(" ") .join(Iterables.filter(Splitter.on(" ").split(oldValue), input -> !value.equals(input)))); return true; } } return false; } }