C++ 和 Java 函数互调-一一网

C++ 和 Java 函数互调

分享经验总结，欢迎加入

QQ 群：686809487

项目如下：

在这里插入图片描述

知识点：

CMakeLists.txt 的使用
c++ 创建子线程，消费者和生产者
ffmpeg 编译
ffmpeg 高低版本库动态切换
ffmpeg 解码音视频
OpenSLES 播放 pcm 音频
soundTouch (变调，变速)导入和使用
pcm 数据分包处理
pcm 数据使用 mediacodec 编码成 aac 文件
OpenGLES 渲染图片
OpenGLES 渲染 YUV 数据
录音
剪切音乐

源码地址：

github.com/taxiao213/n…

build.gradle 配置

android {
    ```
    defaultConfig {
        ndk {
            abiFilters "armeabi-v7a", "arm64-v8a", "x86", "x86_64"
        }
        externalNativeBuild {
            cmake {
                // 传参数
                arguments "-DFFMPEG_BUILD_VERSION=${Integer.valueOf(FFMPEG_BUILD_VERSION)}"
                cppFlags "-fexceptions", "-frtti"
            }
        }
    }
    externalNativeBuild {
        cmake {
            path "src/main/cpp/CMakeLists.txt"
            version "3.10.2"
        }
    }
    ```
}
复制代码

CMakeLists.txt 配置

cmake_minimum_required(VERSION 3.4.1)

if (FFMPEG_BUILD_VERSION EQUAL 1)
    include_directories(include/low_version)
    set(version low_version)
    set(avcodec libavcodec-57.so)
    set(avdevice libavdevice-57.so)
    set(avfilter libavfilter-6.so)
    set(avformat libavformat-57.so)
    set(avutil libavutil-55.so)
    set(postproc libpostproc-54.so)
    set(swresample libswresample-2.so)
    set(swscale libswscale-4.so)
elseif (FFMPEG_BUILD_VERSION EQUAL 2)
    include_directories(include/high_version)
    set(version high_version)
    set(avcodec libavcodec.so)
    set(avdevice libavdevice.so)
    set(avfilter libavfilter.so)
    set(avformat libavformat.so)
    set(avutil libavutil.so)
    set(postproc libpostproc.so)
    set(swresample libswresample.so)
    set(swscale libswscale.so)
endif ()
set(rootPath ${CMAKE_SOURCE_DIR}/../../jniLibs/${version}/${CMAKE_ANDROID_ARCH_ABI})
message("rootPath: ${rootPath}")

add_library(${avcodec} SHARED IMPORTED)
set_target_properties(${avcodec} PROPERTIES IMPORTED_LOCATION ${rootPath}/${avcodec})

add_library(${avdevice} SHARED IMPORTED)
set_target_properties(${avdevice} PROPERTIES IMPORTED_LOCATION ${rootPath}/${avdevice})

add_library(${avfilter} SHARED IMPORTED)
set_target_properties(${avfilter} PROPERTIES IMPORTED_LOCATION ${rootPath}/${avfilter})

add_library(${avformat} SHARED IMPORTED)
set_target_properties(${avformat} PROPERTIES IMPORTED_LOCATION ${rootPath}/${avformat})

add_library(${avutil} SHARED IMPORTED)
set_target_properties(${avutil} PROPERTIES IMPORTED_LOCATION ${rootPath}/${avutil})

add_library(${postproc} SHARED IMPORTED)
set_target_properties(${postproc} PROPERTIES IMPORTED_LOCATION ${rootPath}/${postproc})

add_library(${swresample} SHARED IMPORTED)
set_target_properties(${swresample} PROPERTIES IMPORTED_LOCATION ${rootPath}/${swresample})

add_library(${swscale} SHARED IMPORTED)
set_target_properties(${swscale} PROPERTIES IMPORTED_LOCATION ${rootPath}/${swscale})

include_directories(soundtouch/source)
aux_source_directory(soundtouch/source DIR_SRCS)

add_library(
        native-lib
        SHARED
        ${DIR_SRCS}
        native-lib.cpp
        javaListener.cpp
        TXCallJava.cpp
        TXFFmpeg.cpp
        TXAudio.cpp
        TXQueue.cpp
        TXPlayStatus.cpp
        TXCallBack.cpp
        TXBufferQueue.cpp
        TXPcmBean.cpp
        test/thread_test.cpp
        test/Opensles_test.cpp
        TXVideo.cpp
)

target_link_libraries(
        native-lib
        ${avcodec}
        ${avdevice}
        ${avfilter}
        ${avformat}
        ${avutil}
        ${postproc}
        ${swresample}
        ${swscale}
        OpenSLES
        log)
复制代码

ndk 日志打印

//
// Created by yin13 on 2021/3/17.
//
#include "android/log.h"

#ifndef APPLE_ANDROID_LOG_H
#define APPLE_ANDROID_LOG_H
#endif //APPLE_ANDROID_LOG_H

#define TAG "TA_XIAO"
#define DEBUG 1
#if DEBUG
    #define SDK_LOG_V(FORMAT, ...) __android_log_print(ANDROID_LOG_VERBOSE, TAG, "[%s] line: %d info: " FORMAT, __PRETTY_FUNCTION__, __LINE__, ##__VA_ARGS__)
    #define SDK_LOG_D(FORMAT, ...) __android_log_print(ANDROID_LOG_DEBUG, TAG, "[%s] line: %d info: " FORMAT, __PRETTY_FUNCTION__, __LINE__, ##__VA_ARGS__)
    #define SDK_LOG_W(FORMAT, ...) __android_log_print(ANDROID_LOG_WARN, TAG, "[%s] line: %d info: " FORMAT, __PRETTY_FUNCTION__, __LINE__, ##__VA_ARGS__)
    #define SDK_LOG_E(FORMAT, ...) __android_log_print(ANDROID_LOG_ERROR, TAG, "[%s] line: %d info: " FORMAT, __PRETTY_FUNCTION__, __LINE__, ##__VA_ARGS__)
#else
    #define SDK_LOG_V(FORMAT, ...)
    #define SDK_LOG_D(FORMAT, ...)
    #define SDK_LOG_W(FORMAT, ...)
    #define SDK_LOG_E(FORMAT, ...)
#endif

复制代码

java 调用 c++ 方法

// 导入库，创建 native 方法
    
static {
    if (BuildConfig.FFMPEG_BUILD_VERSION == 1) {
    System.loadLibrary("avcodec-57");
    System.loadLibrary("avdevice-57");
    System.loadLibrary("avfilter-6");
    System.loadLibrary("avformat-57");
    System.loadLibrary("avutil-55");
    System.loadLibrary("postproc-54");
    System.loadLibrary("swresample-2");
    System.loadLibrary("swscale-4");
    } else if (BuildConfig.FFMPEG_BUILD_VERSION == 2) {
    System.loadLibrary("avcodec");
    System.loadLibrary("avdevice");
    System.loadLibrary("avfilter");
    System.loadLibrary("avformat");
    System.loadLibrary("avutil");
    System.loadLibrary("postproc");
    System.loadLibrary("swresample");
    System.loadLibrary("swscale");
    }
    System.loadLibrary("native-lib");
}

public native void javaMain2C();
复制代码

native-lib.cpp 实现相应的方法

extern "C"
JNIEXPORT void JNICALL
Java_com_taxiao_ffmpeg_JniSdkImpl_javaMain2C(JNIEnv *env, jobject jobject1) {
    javaListener = new JavaListener(jvm, env, env->NewGlobalRef(jobject1));
    javaListener->onError(1, 111, "main c++");
}
复制代码

c++ 调用 java 方法

native-lib.cpp 在 JNI_OnLoad 中获取 JavaVM

// 获取JVM
JNIEXPORT jint JNICALL JNI_OnLoad(JavaVM *vm, void *reserved) {
    jvm = vm;
    JNIEnv *env;
    if (jvm->GetEnv((void **) (&env), JNI_VERSION_1_4) != JNI_OK) {
        return -1;
    }
    return JNI_VERSION_1_4;
}
复制代码

TXCallJava.cpp 实现回调方法

// 将 JavaVM 传入回调文件初始化需要回调的方法
TXCallJava::TXCallJava(JavaVM *vm, JNIEnv *env, jobject *obj) {
    this->javaVm = vm;
    this->jniEnv = env;
    
    this->job = jniEnv->NewGlobalRef(*obj);
    jclass aClass = jniEnv->GetObjectClass(job);
    if (aClass) {
        jmethodId = jniEnv->GetMethodID(aClass, JAVA_METHOD_PARPARED, "()V");
        jmethodIdCallLoad = jniEnv->GetMethodID(aClass, JAVA_METHOD_LOAD, "(Z)V");
        jmethodIdTimeInfo = jniEnv->GetMethodID(aClass, JAVA_METHOD_TIME_INFO, "(II)V");
        jmethodIdError = jniEnv->GetMethodID(aClass, JAVA_METHOD_ERROR, "(ILjava/lang/String;)V");
        jmethodIdComplete = jniEnv->GetMethodID(aClass, JAVA_METHOD_COMPLETE, "()V");
        jmethodIdValumeDB = jniEnv->GetMethodID(aClass, JAVA_METHOD_VALUME_DB, "(I)V");
        jmethodIdPcmAAc = jniEnv->GetMethodID(aClass, JAVA_METHOD_PCM_AAC, "(I[B)V");
        jmethodIdRecordTime = jniEnv->GetMethodID(aClass, JAVA_METHOD_RECORD_TIME, "(F)V");
        jmethodIdCutAudio = jniEnv->GetMethodID(aClass, JAVA_METHOD_CUT_AUDIO, "(I[B)V");
        jmethodIdRenderYUV = jniEnv->GetMethodID(aClass, JAVA_METHOD_RENDER_YUV, "(II[B[B[B)V");
        jmethodIdIsSupportMediaCodec = jniEnv->GetMethodID(aClass,
                                                           JAVA_METHOD_IS_SUPPORT_MEDIA_CODEC,
                                                           "(Ljava/lang/String;)Z");
        jmethodIdInitMediaCodecVideo = jniEnv->GetMethodID(aClass,
                                                           JAVA_METHOD_INIT_MEDIA_CODEC_VIDEO,
                                                           "(Ljava/lang/String;II[B[B)V");

        jmethodIdDecodeAvPacket = jniEnv->GetMethodID(aClass, JAVA_METHOD_DECODE_AV_PACKET,
                                                      "(I[B)V");
    }
}

void TXCallJava::onCallOnCutAudio(int type, int sampleRate, int size, void *pcmBuffer) {
    if (type == MAIN_THREAD) {
        jbyteArray pArray = jniEnv->NewByteArray(size);
        jniEnv->SetByteArrayRegion(pArray, 0, size, static_cast<const jbyte *>(pcmBuffer));
        jniEnv->CallVoidMethod(job, jmethodIdCutAudio, sampleRate, pArray);
        jniEnv->DeleteLocalRef(pArray);
    } else if (type == CHILD_THREAD) {
        JNIEnv *env;
        if (javaVm->AttachCurrentThread(&env, 0) != JNI_OK) {
            return;
        }
        jbyteArray pArray = env->NewByteArray(size);
        env->SetByteArrayRegion(pArray, 0, size, static_cast<const jbyte *>(pcmBuffer));
        env->CallVoidMethod(job, jmethodIdCutAudio, sampleRate, pArray);
        env->DeleteLocalRef(pArray);
        javaVm->DetachCurrentThread();
    }
}
复制代码