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JythonJava跳过代码行

我有一个JNI包装器将数组从Fortran传递到Java。现在,我需要Java将这个数组传递给Python并返回值

objFuncType。java如下所示:

public interface objFuncType {
    public double calculateobjFunc(double[] pos);
}

objFunc。java如下所示:

import java.io.*;
import java.util.*;
import org.plyjy.factory.JythonObjectFactory;

public class objFunc {

public static double evaluate(double[] position) {
    double result;
    for (int i=0;i<position.length;i++)
       System.out.println("position ="+position[i]);

    JythonObjectFactory factory = JythonObjectFactory.getInstance();
    System.out.println("JythonObjectFactory created");
    objFuncType func=(objFuncType)factory.createObject(objFuncType.class, "CostCalculator");
    result = func.calculateCost(position);
    System.out.println("Result computed! Result = "+result);
    return result;

    }
}

成本计算器。具体如下:

import objFuncType

class CostCalculator(objFuncType, object):

def __init__(self):
    print 'Initializing'
    pass

def calculateCost(self, chromosome):
    fitness = 0
    for i in range(len(chromosome)-1):
        fitness += 100*((chromosome[i]**2)-chromosome[i+1])**2+\
        (1-chromosome[i])**2
    return fitness

当我从外部程序调用Java函数时,输出如下:

position =1.3653333187103271
position =0.0
position =-1.8204443454742432
position =-1.8204443454742432

数组正在被很好地打印,但是在打印语句之后的所有语句都被跳过。 请帮忙


共 (1) 个答案

  1. # 1 楼答案

    好吧,我知道了。我使用JNI从C调用Java,它似乎不知道在哪里查找jar文件。我在调用Java的C程序中添加了以下代码行。它按预期运行

    JNIEnv* env;
    JavaVMInitArgs args;
    JavaVMOption options[3];
    args.version = JNI_VERSION_1_6;
    args.nOptions = 3;
    options[0].optionString = "-Djava.class.path=./";
    options[1].optionString = "-Djava.class.path=<path_to_class>:<path_to_jars>";
    options[2].optionString = "-Djava.class.path=<path_to_class>:<path_to_jars>";
    args.options = options;
    args.ignoreUnrecognized = 0;
    int status;
    status = JNI_CreateJavaVM(jvm, (void**)&env, &args);
    if (status < 0 || !env)
        printf("Unable to Launch JVM %d\n",rv);
    else
        printf("Launched JVM successfully\n");
    return env;