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运行C++;使用JavaCPP在javaandroid应用程序中编写代码_Java_C++_Android Ndk_Javac_Javacpp - Fatal编程技术网

运行C++;使用JavaCPP在javaandroid应用程序中编写代码

运行C++;使用JavaCPP在javaandroid应用程序中编写代码,java,c++,android-ndk,javac,javacpp,Java,C++,Android Ndk,Javac,Javacpp,对于Android的开发,我是一个初学者,我正在努力理解。我想在Android应用程序中从Java执行C++函数。在我的示例中,我只使用一个简单的TextView小部件,它打印我从C++收到的内容。 在文档之后,在应用程序的build.gradle中,我包含了我的javacpp库依赖项 dependencies { implementation 'org.bytedeco:javacpp:1.5.4' } 以便在我的应用程序中使用它。我在一个本地C++的Android Studio模板

对于Android的开发,我是一个初学者,我正在努力理解。我想在
Android
应用程序中从
Java
执行
C++
函数。在我的示例中,我只使用一个简单的
TextView
小部件,它打印我从
C++
收到的内容。 在文档之后,在应用程序的
build.gradle
中,我包含了我的
javacpp
库依赖项

dependencies {
    implementation 'org.bytedeco:javacpp:1.5.4'
}
以便在我的应用程序中使用它。我在一个本地C++的Android Studio模板项目中测试。 我已将完整项目上传到GitHub以供参考:

此外,下面是我认为需要注意的项目中的相关文件:

NativeLibrary.java

package com.example.javacplusplus;
import org.bytedeco.javacpp.*;
import org.bytedeco.javacpp.annotation.*;

@Platform(include="NativeLibrary.h")
@Namespace("NativeLibrary")
public class NativeLibrary {
    public static class NativeClass extends Pointer {
        static { Loader.load(); }
        public NativeClass() { allocate(); }
        private native void allocate();

        // to call the getter and setter functions
        public native @StdString String get_property();
        public native void set_property(String property);

        // to access the member variable directly
        public native @StdString String property();
        public native void property(String property);
    }
}
#ifndef NATIVELIBRARY_H
#define NATIVELIBRARY_H

#include <string>

namespace NativeLibrary {
    class NativeClass {
    public:
        const std::string& get_property();
        void set_property(const std::string& property);
        std::string property;
    };
}

#endif // NATIVELIBRARY_H
#include "NativeLibrary.h"

namespace NativeLibrary {

const std::string& NativeClass::get_property() { return property; }
void NativeClass::set_property(const std::string& property) { this->property = property; }

} // namespace NativeLibrary
cmake_minimum_required(VERSION 3.4.1)

add_library(
        native-lib

        SHARED

        NativeLibrary.cpp
        native-lib.cpp)

find_library(
        log-lib

        log)

target_link_libraries(
        native-lib

        ${log-lib})
package com.example.javacplusplus;

import androidx.appcompat.app.AppCompatActivity;

import android.os.Bundle;
import android.widget.TextView;

public class MainActivity extends AppCompatActivity {

    // Used to load the 'native-lib' library on application startup.
    static {
        System.loadLibrary("native-lib");
    }

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        // Pointer objects allocated in Java get deallocated once they become unreachable,
        // but C++ destructors can still be called in a timely fashion with Pointer.deallocate()
        NativeLibrary.NativeClass l = new NativeLibrary.NativeClass();
        l.set_property("Hello World!");

        // Example of a call to a native method
        TextView tv = findViewById(R.id.sample_text);
        tv.setText(l.property());
//        tv.setText(stringFromJNI());
    }

    /**
     * A native method that is implemented by the 'native-lib' native library,
     * which is packaged with this application.
     */
    public native String stringFromJNI();
}
国家图书馆.h

package com.example.javacplusplus;
import org.bytedeco.javacpp.*;
import org.bytedeco.javacpp.annotation.*;

@Platform(include="NativeLibrary.h")
@Namespace("NativeLibrary")
public class NativeLibrary {
    public static class NativeClass extends Pointer {
        static { Loader.load(); }
        public NativeClass() { allocate(); }
        private native void allocate();

        // to call the getter and setter functions
        public native @StdString String get_property();
        public native void set_property(String property);

        // to access the member variable directly
        public native @StdString String property();
        public native void property(String property);
    }
}
#ifndef NATIVELIBRARY_H
#define NATIVELIBRARY_H

#include <string>

namespace NativeLibrary {
    class NativeClass {
    public:
        const std::string& get_property();
        void set_property(const std::string& property);
        std::string property;
    };
}

#endif // NATIVELIBRARY_H
#include "NativeLibrary.h"

namespace NativeLibrary {

const std::string& NativeClass::get_property() { return property; }
void NativeClass::set_property(const std::string& property) { this->property = property; }

} // namespace NativeLibrary
cmake_minimum_required(VERSION 3.4.1)

add_library(
        native-lib

        SHARED

        NativeLibrary.cpp
        native-lib.cpp)

find_library(
        log-lib

        log)

target_link_libraries(
        native-lib

        ${log-lib})
package com.example.javacplusplus;

import androidx.appcompat.app.AppCompatActivity;

import android.os.Bundle;
import android.widget.TextView;

public class MainActivity extends AppCompatActivity {

    // Used to load the 'native-lib' library on application startup.
    static {
        System.loadLibrary("native-lib");
    }

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        // Pointer objects allocated in Java get deallocated once they become unreachable,
        // but C++ destructors can still be called in a timely fashion with Pointer.deallocate()
        NativeLibrary.NativeClass l = new NativeLibrary.NativeClass();
        l.set_property("Hello World!");

        // Example of a call to a native method
        TextView tv = findViewById(R.id.sample_text);
        tv.setText(l.property());
//        tv.setText(stringFromJNI());
    }

    /**
     * A native method that is implemented by the 'native-lib' native library,
     * which is packaged with this application.
     */
    public native String stringFromJNI();
}
CMakeLists.txt

package com.example.javacplusplus;
import org.bytedeco.javacpp.*;
import org.bytedeco.javacpp.annotation.*;

@Platform(include="NativeLibrary.h")
@Namespace("NativeLibrary")
public class NativeLibrary {
    public static class NativeClass extends Pointer {
        static { Loader.load(); }
        public NativeClass() { allocate(); }
        private native void allocate();

        // to call the getter and setter functions
        public native @StdString String get_property();
        public native void set_property(String property);

        // to access the member variable directly
        public native @StdString String property();
        public native void property(String property);
    }
}
#ifndef NATIVELIBRARY_H
#define NATIVELIBRARY_H

#include <string>

namespace NativeLibrary {
    class NativeClass {
    public:
        const std::string& get_property();
        void set_property(const std::string& property);
        std::string property;
    };
}

#endif // NATIVELIBRARY_H
#include "NativeLibrary.h"

namespace NativeLibrary {

const std::string& NativeClass::get_property() { return property; }
void NativeClass::set_property(const std::string& property) { this->property = property; }

} // namespace NativeLibrary
cmake_minimum_required(VERSION 3.4.1)

add_library(
        native-lib

        SHARED

        NativeLibrary.cpp
        native-lib.cpp)

find_library(
        log-lib

        log)

target_link_libraries(
        native-lib

        ${log-lib})
package com.example.javacplusplus;

import androidx.appcompat.app.AppCompatActivity;

import android.os.Bundle;
import android.widget.TextView;

public class MainActivity extends AppCompatActivity {

    // Used to load the 'native-lib' library on application startup.
    static {
        System.loadLibrary("native-lib");
    }

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        // Pointer objects allocated in Java get deallocated once they become unreachable,
        // but C++ destructors can still be called in a timely fashion with Pointer.deallocate()
        NativeLibrary.NativeClass l = new NativeLibrary.NativeClass();
        l.set_property("Hello World!");

        // Example of a call to a native method
        TextView tv = findViewById(R.id.sample_text);
        tv.setText(l.property());
//        tv.setText(stringFromJNI());
    }

    /**
     * A native method that is implemented by the 'native-lib' native library,
     * which is packaged with this application.
     */
    public native String stringFromJNI();
}

注意NATIVE-LIB CPP只是模板中使用的C++文件,我现在忽略它。 build.gradle(对应于

应用程序
模块):

MainActivity.java

package com.example.javacplusplus;
import org.bytedeco.javacpp.*;
import org.bytedeco.javacpp.annotation.*;

@Platform(include="NativeLibrary.h")
@Namespace("NativeLibrary")
public class NativeLibrary {
    public static class NativeClass extends Pointer {
        static { Loader.load(); }
        public NativeClass() { allocate(); }
        private native void allocate();

        // to call the getter and setter functions
        public native @StdString String get_property();
        public native void set_property(String property);

        // to access the member variable directly
        public native @StdString String property();
        public native void property(String property);
    }
}
#ifndef NATIVELIBRARY_H
#define NATIVELIBRARY_H

#include <string>

namespace NativeLibrary {
    class NativeClass {
    public:
        const std::string& get_property();
        void set_property(const std::string& property);
        std::string property;
    };
}

#endif // NATIVELIBRARY_H
#include "NativeLibrary.h"

namespace NativeLibrary {

const std::string& NativeClass::get_property() { return property; }
void NativeClass::set_property(const std::string& property) { this->property = property; }

} // namespace NativeLibrary
cmake_minimum_required(VERSION 3.4.1)

add_library(
        native-lib

        SHARED

        NativeLibrary.cpp
        native-lib.cpp)

find_library(
        log-lib

        log)

target_link_libraries(
        native-lib

        ${log-lib})
package com.example.javacplusplus;

import androidx.appcompat.app.AppCompatActivity;

import android.os.Bundle;
import android.widget.TextView;

public class MainActivity extends AppCompatActivity {

    // Used to load the 'native-lib' library on application startup.
    static {
        System.loadLibrary("native-lib");
    }

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        // Pointer objects allocated in Java get deallocated once they become unreachable,
        // but C++ destructors can still be called in a timely fashion with Pointer.deallocate()
        NativeLibrary.NativeClass l = new NativeLibrary.NativeClass();
        l.set_property("Hello World!");

        // Example of a call to a native method
        TextView tv = findViewById(R.id.sample_text);
        tv.setText(l.property());
//        tv.setText(stringFromJNI());
    }

    /**
     * A native method that is implemented by the 'native-lib' native library,
     * which is packaged with this application.
     */
    public native String stringFromJNI();
}
应用程序构建良好,但在运行时在
nativellibrary.NativeClass l=new nativellibrary.NativeClass()内崩溃,带有消息
无法找到“libjniationallibrary.so”
这是我的崩溃日志:

    --------- beginning of crash
2020-11-16 00:57:38.557 13506-13506/? E/AndroidRuntime: FATAL EXCEPTION: main
    Process: com.example.javacppapp, PID: 13506
    java.lang.UnsatisfiedLinkError: dalvik.system.PathClassLoader[DexPathList[[zip file "/data/app/com.example.javacppapp-8V-wRac6X4RLpYvvYEmtGQ==/base.apk", zip file "/data/app/com.example.javacppapp-8V-wRac6X4RLpYvvYEmtGQ==/split_lib_dependencies_apk.apk", zip file "/data/app/com.example.javacppapp-8V-wRac6X4RLpYvvYEmtGQ==/split_lib_resources_apk.apk", zip file "/data/app/com.example.javacppapp-8V-wRac6X4RLpYvvYEmtGQ==/split_lib_slice_0_apk.apk", zip file "/data/app/com.example.javacppapp-8V-wRac6X4RLpYvvYEmtGQ==/split_lib_slice_1_apk.apk", zip file "/data/app/com.example.javacppapp-8V-wRac6X4RLpYvvYEmtGQ==/split_lib_slice_2_apk.apk", zip file "/data/app/com.example.javacppapp-8V-wRac6X4RLpYvvYEmtGQ==/split_lib_slice_3_apk.apk", zip file "/data/app/com.example.javacppapp-8V-wRac6X4RLpYvvYEmtGQ==/split_lib_slice_4_apk.apk", zip file "/data/app/com.example.javacppapp-8V-wRac6X4RLpYvvYEmtGQ==/split_lib_slice_5_apk.apk", zip file "/data/app/com.example.javacppapp-8V-wRac6X4RLpYvvYEmtGQ==/split_lib_slice_6_apk.apk", zip file "/data/app/com.example.javacppapp-8V-wRac6X4RLpYvvYEmtGQ==/split_lib_slice_7_apk.apk", zip file "/data/app/com.example.javacppapp-8V-wRac6X4RLpYvvYEmtGQ==/split_lib_slice_8_apk.apk", zip file "/data/app/com.example.javacppapp-8V-wRac6X4RLpYvvYEmtGQ==/split_lib_slice_9_apk.apk"],nativeLibraryDirectories=[/data/app/com.example.javacppapp-8V-wRac6X4RLpYvvYEmtGQ==/lib/x86, /data/app/com.example.javacppapp-8V-wRac6X4RLpYvvYEmtGQ==/base.apk!/lib/x86, /data/app/com.example.javacppapp-8V-wRac6X4RLpYvvYEmtGQ==/split_lib_dependencies_apk.apk!/lib/x86, /data/app/com.example.javacppapp-8V-wRac6X4RLpYvvYEmtGQ==/split_lib_resources_apk.apk!/lib/x86, /data/app/com.example.javacppapp-8V-wRac6X4RLpYvvYEmtGQ==/split_lib_slice_0_apk.apk!/lib/x86, /data/app/com.example.javacppapp-8V-wRac6X4RLpYvvYEmtGQ==/split_lib_slice_1_apk.apk!/lib/x86, /data/app/com.example.javacppapp-8V-wRac6X4RLpYvvYEmtGQ==/split_lib_slice_2_apk.apk!/lib/x86, /data/app/com.example.javacppapp-8V-wRac6X4RLpYvvYEmtGQ==/split_lib_slice_3_apk.apk!/lib/x86, /data/app/com.example.javacppapp-8V-wRac6X4RLpYvvYEmtGQ==/split_lib_slice_4_apk.apk!/lib/x86, /data/app/com.example.javacppapp-8V-wRac6X4RLpYvvYEmtGQ==/split_lib_slice_5_apk.apk!/lib/x86, /data/app/com.example.javacppapp-8V-wRac6X4RLpYvvYEmtGQ==/split_lib_slice_6_apk.apk!/lib/x86, /data/app/com.example.javacppapp-8V-wRac6X4RLpYvvYEmtGQ==/split_lib_slice_7_apk.apk!/lib/x86, /data/app/com.example.javacppapp-8V-wRac6X4RLpYvvYEmtGQ==/split_lib_slice_8_apk.apk!/lib/x86, /data/app/com.example.javacppapp-8V-wRac6X4RLpYvvYEmtGQ==/split_lib_slice_9_apk.apk!/lib/x86, /system/lib]]] couldn't find "libjniNativeLibrary.so"
        at java.lang.Runtime.loadLibrary0(Runtime.java:1012)
        at java.lang.System.loadLibrary(System.java:1669)
        at org.bytedeco.javacpp.Loader.loadLibrary(Loader.java:1683)
        at org.bytedeco.javacpp.Loader.load(Loader.java:1300)
        at org.bytedeco.javacpp.Loader.load(Loader.java:1123)
        at com.example.javacppapp.NativeLibrary$NativeClass.<clinit>(NativeLibrary.java:10)
        at com.example.javacppapp.MainActivity.onCreate(MainActivity.java:22)
        at android.app.Activity.performCreate(Activity.java:7136)
        at android.app.Activity.performCreate(Activity.java:7127)
        at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1271)
        at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2893)
        at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3048)
        at android.app.servertransaction.LaunchActivityItem.execute(LaunchActivityItem.java:78)
        at android.app.servertransaction.TransactionExecutor.executeCallbacks(TransactionExecutor.java:108)
        at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:68)
        at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1808)
        at android.os.Handler.dispatchMessage(Handler.java:106)
        at android.os.Looper.loop(Looper.java:193)
2020-11-16 00:57:38.557 13506-13506/? E/AndroidRuntime:     at android.app.ActivityThread.main(ActivityThread.java:6669)
        at java.lang.reflect.Method.invoke(Native Method)
        at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:493)
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:858)

产量

$ javac -cp javacpp.jar NativeLibrary.java
$ java -jar javacpp.jar NativeLibrary
$ java -cp javacpp.jar NativeLibrary
$ Hello World!
你好,世界所以它工作正常。但我不知道为什么它在Android应用程序中不起作用

有人能帮我吗?有人知道为什么它找不到libjniationalLibrary.so
?为了完成设置,我是否需要添加一些内容?可能是
libjniationallibrary。所以需要以某种方式生成

编辑1: 我已经将
Build Plugin
Platform Plugin
添加到项目的
Build.gradle
文件中;现在的情况是这样的:

// Top-level build file where you can add configuration options common to all sub-projects/modules.

buildscript {
    repositories {
        google()
        jcenter()
    }
    dependencies {
        classpath "com.android.tools.build:gradle:4.1.1"

        // NOTE: Do not place your application dependencies here; they belong
        // in the individual module build.gradle files
    }
}

plugins {
    id 'java-library'
    id 'java-gradle-plugin'
    id 'org.bytedeco.gradle-javacpp-build' version "$javacppVersion"
    id 'org.bytedeco.gradle-javacpp-platform' version "$javacppVersion"
}

ext {
    javacppPlatform = 'android-arm64' // or any other platform, defaults to Loader.getPlatform()
}

dependencies {
    implementation gradleApi()
    api "org.bytedeco:javacpp:$javacppVersion"
}

allprojects {
    repositories {
        google()
        jcenter()
    }
}

// Note: Had to comment this as I was getting the error > Cannot add task 'clean' as a task with that name already exists.
//task clean(type: Delete) {
//    delete rootProject.buildDir
//}

tasks.withType(org.bytedeco.gradle.javacpp.BuildTask) {
    // set here default values for all build tasks below, typically just includePath and linkPath,
    // but also properties to set the path to the NDK and its compiler in the case of Android
}

javacppBuildCommand {
    // typically set here the buildCommand to the script that fills up includePath and linkPath
}

javacppBuildParser {
    // typically set here the classOrPackageNames to class names implementing InfoMap
}

javacppBuildCompiler {
    // typically set here boolean flags like copyLibs
}
项目同步时不会出现错误,但当我运行它时,我会得到:

> Task :javacppBuildParser FAILED
Execution failed for task ':javacppBuildParser'.
> app/build/intermediates/javac/debug/classes/com/example/myjavacppapp/BuildConfig (wrong name: com/example/myjavacppapp/BuildConfig)
是因为我没有在
javacppBuildCommand
javacppBuildParser
javacppBuildParser
中编写任何内容吗? 我知道这是一个基本问题,但有人知道我应该在这些块中写些什么吗?我对这个很陌生,我不知道在哪里可以找到这些信息

编辑2: 在尝试了上面的编辑1中介绍的解决方案后,我看到了wiki页面,并按照那里的说明将其添加到我的应用程序的
build.gradle
文件中:

import org.bytedeco.javacpp.*;
import org.bytedeco.javacpp.annotation.*;

@Platform(include="NativeLibrary.h")
@Namespace("NativeLibrary")
public class NativeLibrary {
    public static class NativeClass extends Pointer {
        static { Loader.load(); }
        public NativeClass() { allocate(); }
        private native void allocate();

        // to call the getter and setter functions 
        public native @StdString String get_property();
        public native void set_property(String property);

        // to access the member variable directly
        public native @StdString String property();
        public native void property(String property);
    }

    public static void main(String[] args) {
        // Pointer objects allocated in Java get deallocated once they become unreachable,
        // but C++ destructors can still be called in a timely fashion with Pointer.deallocate()
        NativeClass l = new NativeClass();
        l.set_property("Hello World!");
        System.out.println(l.property());
    }
}
android {
    applicationVariants.all { variant ->
        variant.javaCompiler.doLast {
            println 'javacpp ' + variant.name
            javaexec {
                main 'org.bytedeco.javacpp.tools.Builder'
                classpath '/home/jacob/Work/other/sandbox/java/javacpp3/app/libs/javacpp.jar'
                args '-cp', variant.javaCompiler.destinationDir,
                        '-properties', 'android-arm',
                        '-Dplatform.root=/home/jacob/.android/sdk/ndk/21.1.6352462',
                        '-Dplatform.compiler=/home/jacob/.android/sdk/ndk/21.1.6352462/toolchains/arm-linux-androideabi-4.9/prebuilt/linux-x86_64/bin/arm-linux-androideabi-g++',
                        '-Dplatform.includepath=/home/jacob/.android/sdk/ndk/21.1.6352462/sources/cxx-stl/gnu-libstdc++/include:src/main/cpp',
                        '-Dplatform.linkpath=/home/jacob/.android/sdk/ndk/21.1.6352462/sources/cxx-stl/llvm-libc++/libs/arm64-v8a',
                        '-d', 'libs/armeabi'
            }
            println 'javacpp done'
        }
    }

    sourceSets.main {
        jniLibs.srcDir 'libs'
        jni.srcDirs = [] // disable automatic ndk-build call
    }
}
gradle同步运行正常,但当我构建项目时,我得到:

> Task :app:compileDebugJavaWithJavac FAILED
javacpp debug
Exception in thread "main" java.lang.NoClassDefFoundError: androidx/appcompat/app/AppCompatActivity
    at java.lang.ClassLoader.defineClass1(Native Method)
    at java.lang.ClassLoader.defineClass(ClassLoader.java:763)
    at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:142)
    at java.net.URLClassLoader.defineClass(URLClassLoader.java:467)
    at java.net.URLClassLoader.access$100(URLClassLoader.java:73)
    at java.net.URLClassLoader$1.run(URLClassLoader.java:368)
    at java.net.URLClassLoader$1.run(URLClassLoader.java:362)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.net.URLClassLoader.findClass(URLClassLoader.java:361)
    at org.bytedeco.javacpp.tools.UserClassLoader.findClass(UserClassLoader.java:72)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
    at java.lang.Class.forName0(Native Method)
    at java.lang.Class.forName(Class.java:348)
    at org.bytedeco.javacpp.tools.ClassScanner.addClass(ClassScanner.java:61)
    at org.bytedeco.javacpp.tools.ClassScanner.addMatchingFile(ClassScanner.java:75)
    at org.bytedeco.javacpp.tools.ClassScanner.addMatchingDir(ClassScanner.java:87)
    at org.bytedeco.javacpp.tools.ClassScanner.addMatchingDir(ClassScanner.java:85)
    at org.bytedeco.javacpp.tools.ClassScanner.addMatchingDir(ClassScanner.java:85)
    at org.bytedeco.javacpp.tools.ClassScanner.addMatchingDir(ClassScanner.java:85)
    at org.bytedeco.javacpp.tools.ClassScanner.addPackage(ClassScanner.java:99)
    at org.bytedeco.javacpp.tools.Builder.classesOrPackages(Builder.java:672)
    at org.bytedeco.javacpp.tools.Builder.main(Builder.java:962)
Caused by: java.lang.ClassNotFoundException: androidx.appcompat.app.AppCompatActivity
    at java.net.URLClassLoader.findClass(URLClassLoader.java:381)
    at org.bytedeco.javacpp.tools.UserClassLoader.findClass(UserClassLoader.java:72)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
    ... 23 more

FAILURE: Build failed with an exception.

* Where:
Build file '/home/jacob/Work/other/sandbox/java/javacpp3/app/build.gradle' line: 48

* What went wrong:
Execution failed for task ':app:compileDebugJavaWithJavac'.
> Process 'command '/home/jacob/.android/studio/jre/bin/java'' finished with non-zero exit value 1

你知道我如何解决这个问题吗?

我在这里发布了一个完整的工作示例:

作为参考,我们可以通过以下步骤复制此项目:

  • 按照
  • app/build.gradle
    文件中添加如下内容(以通常方式应用
    org.bytedeco.gradle javacpp build
    插件之后),以及
  • 更新
    CMakeLists.txt
    文件以包含生成的
    .cpp
    文件

  • 我看不出你在哪里调用JavaCPP生成器?类似这样的话:@SamuelAudet非常感谢您的回答和建议!我已尝试添加
    构建插件
    平台插件
    ,请检查我对上述问题的编辑1更新?请您帮助我理解它失败的原因,以及我应该在
    javacppBuildCommand
    javacppBuildParser
    javacppBuildParser
    中放置什么。我知道这可能是一些基本的东西,但我才刚刚开始了解Gradle,我不知道在哪里可以找到这些具体的信息。非常感谢你!这里有一个工作的例子:顺便说一句,这里有人似乎让它工作没有任何问题:请尝试联系他们,看看他们是否准备好发布代码!Thanks@HarshSavergaonkar非常感谢你的回答。是的,我知道JNI为桥接C++和java提供的机制,我知道如何使用它们。但是,它们没有提供JavaCPP提供的易用性。使用Javapp,您可以拥有直接在Java中实现的C++接口,这在维护性方面非常有用。例如,我正在寻找一个简单的Android示例,在其中我可以在java中实现C++ java函数。