Java tutorial
/* * 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.facebook.presto.resourceGroups; import com.google.common.collect.ImmutableMap; import java.util.Map; import static java.util.Objects.requireNonNull; public class VariableMap { private static final VariableMap EMPTY_VARIABLE_MAP = new VariableMap(ImmutableMap.of()); private final Map<String, String> variables; public VariableMap(Map<String, String> variables) { this.variables = ImmutableMap.copyOf(requireNonNull(variables, "variables is null")); } public String getValue(String key) { return variables.get(key); } @Override public String toString() { return variables.toString(); } public static VariableMap emptyVariableMap() { return EMPTY_VARIABLE_MAP; } }