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/*
* Copyright (C) 2010 The Android Open Source Project
*
* 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.
*/
#ifndef JNI_CONSTANTS_H_included
#define JNI_CONSTANTS_H_included
#include "JNIHelp.h"
/**
* A cache to avoid calling FindClass at runtime.
*
* Class lookup is relatively expensive, so we do these lookups at startup. This means that code
* that never uses, say, java.util.zip.Deflater still has to pay for the lookup, but it means that
* on device the cost is paid during boot and amortized. A central cache also removes the temptation
* to dynamically call FindClass rather than add a small cache to each file that needs one. Another
* cost is that each class cached here requires a global reference, though in practice we save
* enough by not having a global reference for each file that uses a class such as java.lang.String
* which is used in several files.
*
* FindClass is still called in a couple of situations: when throwing exceptions, and in some of
* the serialization code. The former is clearly not a performance case, and we're currently
* assuming that neither is the latter.
*
* TODO: similar arguments hold for field and method IDs; we should cache them centrally too.
*/
struct JniConstants {
static void init(JNIEnv* env);
static jclass bidiRunClass;
static jclass bigDecimalClass;
static jclass booleanClass;
static jclass byteArrayClass;
static jclass byteClass;
static jclass calendarClass;
static jclass characterClass;
static jclass charsetICUClass;
static jclass constructorClass;
static jclass deflaterClass;
static jclass doubleClass;
static jclass errnoExceptionClass;
static jclass fieldClass;
static jclass fieldPositionIteratorClass;
static jclass fileDescriptorClass;
static jclass floatClass;
static jclass gaiExceptionClass;
static jclass inet6AddressClass;
static jclass inetAddressClass;
static jclass inetSocketAddressClass;
static jclass inetUnixAddressClass;
static jclass inflaterClass;
static jclass inputStreamClass;
static jclass integerClass;
static jclass localeDataClass;
static jclass longClass;
static jclass methodClass;
static jclass mutableIntClass;
static jclass mutableLongClass;
static jclass netlinkSocketAddressClass;
static jclass objectClass;
static jclass objectArrayClass;
static jclass outputStreamClass;
static jclass packetSocketAddressClass;
static jclass parsePositionClass;
static jclass patternSyntaxExceptionClass;
static jclass realToStringClass;
static jclass referenceClass;
static jclass shortClass;
static jclass socketClass;
static jclass socketImplClass;
static jclass stringClass;
static jclass structAddrinfoClass;
static jclass structFlockClass;
static jclass structGroupReqClass;
static jclass structGroupSourceReqClass;
static jclass structLingerClass;
static jclass structPasswdClass;
static jclass structPollfdClass;
static jclass structStatClass;
static jclass structStatVfsClass;
static jclass structTimevalClass;
static jclass structUcredClass;
static jclass structUtsnameClass;
static jclass zipEntryClass;
};
#define NATIVE_METHOD(className, functionName, signature) \
{ #functionName, signature, reinterpret_cast<void*>(className ## _ ## functionName) }
#endif // JNI_CONSTANTS_H_included
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