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A framework for building native apps with React
/**
* Copyright (c) 2015-present, Facebook, Inc.
* All rights reserved.
*
* This source code is licensed under the BSD-style license found in the
* LICENSE file in the root directory of this source tree. An additional grant
* of patent rights can be found in the PATENTS file in the same directory.
*/
package com.facebook.react.bridge;
import java.util.Map;
/**
* A native module whose API can be provided to JS catalyst instances. {@link NativeModule}s whose
* implementation is written in Java should extend {@link BaseJavaModule} or {@link
* ReactContextBaseJavaModule}. {@link NativeModule}s whose implementation is written in C++
* must not provide any Java code (so they can be reused on other platforms), and instead should
* register themselves using {@link CxxModuleWrapper}.
*/
public interface NativeModule {
interface NativeMethod {
void invoke(CatalystInstance catalystInstance, ExecutorToken executorToken, ReadableNativeArray parameters);
String getType();
}
/**
* A method that can be called from JS synchronously on the JS thread and return a result.
* @see ReactSyncHook
*/
interface SyncNativeHook {
}
/**
* @return the name of this module. This will be the name used to {@code require()} this module
* from javascript.
*/
String getName();
/**
* @return methods callable from JS on this module
*/
Map getMethods();
/**
* This is called at the end of {@link CatalystApplicationFragment#createCatalystInstance()}
* after the CatalystInstance has been created, in order to initialize NativeModules that require
* the CatalystInstance or JS modules.
*/
void initialize();
/**
* Return true if you intend to override some other native module that was registered e.g. as part
* of a different package (such as the core one). Trying to override without returning true from
* this method is considered an error and will throw an exception during initialization. By
* default all modules return false.
*/
boolean canOverrideExistingModule();
/**
* Called before {CatalystInstance#onHostDestroy}
*/
void onCatalystInstanceDestroy();
/**
* In order to support web workers, a module must be aware that it can be invoked from multiple
* different JS VMs. Supporting web workers means recognizing things like:
*
* 1) ids (e.g. timer ids, request ids, etc.) may only unique on a per-VM basis
* 2) the module needs to make sure to enqueue callbacks and JS module calls to the correct VM
*
* In order to facilitate this, modules that support web workers will have all their @ReactMethod-
* annotated methods passed a {@link ExecutorToken} as the first parameter before any arguments
* from JS. This ExecutorToken internally maps to a specific JS VM and can be used by the
* framework to route calls appropriately. In order to make JS module calls correctly, start using
* the version of {@link ReactContext#getJSModule(ExecutorToken, Class)} that takes an
* ExecutorToken. It will ensure that any calls you dispatch to the returned object will go to
* the right VM. For Callbacks, you don't have to do anything special -- the framework
* automatically tags them with the correct ExecutorToken when the are created.
*
* Note: even though calls can come from multiple JS VMs on multiple threads, calls to this module
* will still only occur on a single thread.
*
* @return whether this module supports web workers.
*/
boolean supportsWebWorkers();
}