JNI_learn/src/main/java/space/anyi/jni/parameter/Main.java

package space.anyi.jni.parameter;

import java.util.Arrays;

public class Main {
    static {
        System.load("/home/yangyi/JNI-learn/c/parameter/JNI_parameter.so");
        System.load("/home/yangyi/JNI-learn/c/parameter/JNI_object_parameter.so");
    }
    public static void main(String[] args) {
        //JNI基本数据类型的传递
//        BaseTypeTest baseTypeTest = new BaseTypeTest();
//        int sum = baseTypeTest.sum(1, 2);
//        System.out.println(sum);
//        boolean flag = baseTypeTest.booleanTypeTest(false);
//        System.out.println(flag);

        //JNI对象数据类型的传递
        ObjectTest objectTest = new ObjectTest();
        Student student = objectTest.getStudent();
        System.out.println(student);
        objectTest.printStudentInfo(student);
        System.out.println(student);
//        objectTest.free(student);
    }
}
class BaseTypeTest {
    //定义一个有参数和返回值的native方法
    native int sum(int val1,int val2);
    //boolean类型的测试
    native boolean booleanTypeTest(boolean flag);
}
class ObjectTest{
    /**
     * 通过JNI获取对象,返回的是全局的JNI引用,需要手动管理,有内存泄露的风险
     * @return
     */
    native Student getStudent();
    native void printStudentInfo(Student student);

    /**
     * 释放JNI创建的全局引用
     * @param student
     */
    native void free(Student student);
}
class Student{
    private String name;
    private int age;
    private float height;
    private int[] source;
    private String[] hobby;

    public Student(String name) {
        this.name = name;
    }

    public int getAge() {
        return age;
    }

    public void setAge(int age) {
        this.age = age;
    }

    public float getHeight() {
        return height;
    }

    public void setHeight(float height) {
        this.height = height;
    }

    public int[] getSource() {
        return source;
    }

    public void setSource(int[] source) {
        this.source = source;
    }

    public String[] getHobby() {
        return hobby;
    }

    public void setHobby(String[] hobby) {
        this.hobby = hobby;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public void info(){
        System.out.println("My name is %s,i am %d year old,height:%f".formatted(this.name,this.age,this.height));
    }

    @Override
    public String toString() {
        return "Student{" +
                "name='" + name + '\'' +
                ", age=" + age +
                ", height=" + height +
                ", source=" + Arrays.toString(source) +
                ", hobby=" + Arrays.toString(hobby) +
                '}';
    }
}