JavaCPP提供了在Java中高效访问本地C++的方法。采用JNI技术实现,支持所有Java实现包括Android系统,Avian 和 RoboVM。
JavaCPP提供了一系列的Annotation将Java代码映射到C++代码,并使用一个可执行的jar包将C++代码转化为可以从JVM内调用的动态链接库文件。
Maven:
- <dependency>
- <groupId>org.bytedeco</groupId>
- <artifactId>javacpp</artifactId>
- <version>0.11</version>
- </dependency>
使用方法:
C++:
- #include <string>
- namespace LegacyLibrary {
- class LegacyClass {
- public:
- const std::string& get_property() { return property; }
- void set_property(const std::string& property) { this->property = property; }
- std::string property;
- };
- }
Java:
- import org.bytedeco.javacpp.*;
- import org.bytedeco.javacpp.annotation.*;
- @Platform(include="LegacyLibrary.h")
- @Namespace("LegacyLibrary")
- public class LegacyLibrary {
- public static class LegacyClass extends Pointer {
- static { Loader.load(); }
- public LegacyClass() { 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()
- LegacyClass l = new LegacyClass();
- l.set_property("Hello World!");
- System.out.println(l.property());
- }
- }