JavaCPP 的 std::map<std::string,std::string> 转换答案

【问题标题】：std::map<std::string,std::string> conversion of JavaCPPJavaCPP 的 std::map<std::string,std::string> 转换
【发布时间】：2017-12-13 02:38:03
【问题描述】：

我是JavaCPP的新手，现在遇到了问题。

我的 TestLibrary.h：

#include <string>
#include <map>


    class TestClass {
        public:
            TestClass() {
                property["a"]="b";
            }
            const std::map<std::string,std::string>& getMap(std::string str) { 
                if (str == "a"){
                    return property; 
                }
            }
            std::map<std::string,std::string> property;
    };

TestLibrary.java

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

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

        public static native @ByRef KeyValueMap getMap(String str);    
    }

@Name("std::map<std::string,std::string>") public static class 
KeyValueMap extends Pointer { 
     static { Loader.load(); } 
     public KeyValueMap(Pointer p) { super(p); } 
     public KeyValueMap()       { allocate();  } 
     private native void allocate(); 

     public native long size(); 

     @Index public native @StdString BytePointer get(@StdString 
BytePointer i); 
     public native KeyValueMap put(@StdString BytePointer i, BytePointer 
value); 
} 

    public static void main(String[] args) {
        TestClass l = new TestClass();
        KeyValueMap m = l.getMap("a");
        System.out.println(m);
        //System.out.println(m.get("a"));
    }
}

当

javac -cp javacpp.jar TestLibrary.java
java -jar javacpp.jar 测试库

jniTestLibrary.cpp:2238:30：错误：调用非静态成员没有对象参数的函数 rptr = &::TestClass::getMap(ptr0);
~~~~~~~~~~~~~^~~~~~~

上面的代码是根据 NativeLibrary 示例修改的。但是如何解决编译问题？我可以这样使用m.get("a") 吗？

【问题讨论】：

标签： javacpp

【解决方案1】：

我设法通过改变来做到这一点......

TestLibrary.h：

#include <string>
#include <map>


class TestClass {
    public:
        TestClass() {
            property["a"]="b";
        }
        std::map<std::string,std::string>& getMap(std::string str) { 
            if (str == "a"){
                return property; 
            }
        }
        std::map<std::string,std::string> property;
};

TestLibrary.java

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

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

    public native @ByRef KeyValueMap getMap(String str);    
}

@Name("std::map<std::string,std::string>") 
public static class KeyValueMap extends Pointer { 
 static { Loader.load(); } 
 public KeyValueMap(Pointer p) { super(p); } 
 public KeyValueMap()       { allocate();  } 
 private native void allocate(); 

 public native long size(); 

 @Index public native @StdString BytePointer get(@StdString BytePointer i); 
 public native KeyValueMap put(@StdString BytePointer i, BytePointer value); } 

public static void main(String[] args) {
    TestClass l = new TestClass();
    KeyValueMap m = l.getMap("a");
    System.out.println(m.size());
    System.out.println(m.get(new BytePointer("a")).getString());
}}

【讨论】：