1 // Copyright (C) 2018 The Android Open Source Project 2 // 3 // Licensed under the Apache License, Version 2.0 (the "License"); 4 // you may not use this file except in compliance with the License. 5 // You may obtain a copy of the License at 6 // 7 // http://www.apache.org/licenses/LICENSE-2.0 8 // 9 // Unless required by applicable law or agreed to in writing, software 10 // distributed under the License is distributed on an "AS IS" BASIS, 11 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 12 // See the License for the specific language governing permissions and 13 // limitations under the License. 14 15 export interface HasKind { kind: string; } 16 17 export class Registry<T extends HasKind> { 18 private registry: Map<string, T>; 19 20 constructor() { 21 this.registry = new Map<string, T>(); 22 } 23 24 register(registrant: T) { 25 const kind = registrant.kind; 26 if (this.registry.has(kind)) { 27 throw new Error(`Registrant ${kind} already exists in the registry`); 28 } 29 this.registry.set(kind, registrant); 30 } 31 32 has(kind: string): boolean { 33 return this.registry.has(kind); 34 } 35 36 get(kind: string): T { 37 const registrant = this.registry.get(kind); 38 if (registrant === undefined) { 39 throw new Error(`${kind} has not been registered.`); 40 } 41 return registrant; 42 } 43 44 unregisterAllForTesting(): void { 45 this.registry.clear(); 46 } 47 } 48