在eclipse中,在64位窗口上,我試圖獲得一個JNI示例,包括嘗試兩種處理輸入/輸出int參數的方法。該程序運行並執行sayHello(),但以modIntPtr()的以下異常終止:JNI UnsatisfiedLinkError ...簽名差異?
線程「main」中的異常java.lang.UnsatisfiedLinkError:com.aaa.bbb.ccc.HelloJNI.modIntPtr(I [我)V 在com.aaa.bbb.ccc.HelloJNI.modIntPtr(本機方法) 在com.aaa.bbb.ccc.HelloJNI.main(HelloJNI.java:18)
我雙重檢查庫,它的確有modIntPtr。所以我認爲這一定是一個簽名問題?在.cpp文件中,modIntPtr有一個jint,jintArray,並返回一個void。那是(I [I] V。在.h文件中,簽名是(I [I)V。在HelloJNI.java中,我這樣調用它: new HelloJNI()。modIntPtr(100,intptr); intptr是類型int []。那也是(I [I] V)。
因此,如果.dll包含modIntPtr方法,我相信它是最新的,我確信該程序與正確的.dll鏈接,這不是一個簽名問題,還有什麼可以?
順便說一句,如果我註釋掉對modIntPtr的調用,modIntRef就可以工作。
感謝您的幫助!
HelloJNI.java:
package com.aaa.bbb.ccc;
public class HelloJNI {
static {
System.loadLibrary("com_aaa_bbb_ccc");
}
// A native method that receives nothing and returns void
private native void sayHello();
private native void modIntPtr(int delta, int[] intptr);
private native void modIntRef(int delta, IntRef intref);
public static void main(String[] args) {
int[] intptr = new int[1];
intptr[0]=42;
IntRef intref = new IntRef(24);
new HelloJNI().sayHello(); // invoke the native method
new HelloJNI().modIntPtr(100, intptr);
new HelloJNI().modIntRef(100, intref);
}
}
HelloJNI.cpp
#include <jni.h>
#include <stdio.h>
#include "HelloJNI.h"
void SayHello(void)
{
printf("Hello World!\n");
return;
}
void IntRefNative(int delta, int *intptr)
{
printf("delta = %d\n",delta);
printf("intptr = %d\n",*intptr);
*intptr += delta;
printf("After mod...\n");
printf("intptr = %d\n",*intptr);
return;
}
JNIEXPORT void JNICALL Java_com_aaa_bbb_ccc_HelloJNI_sayHello(JNIEnv *env, jobject thisObj) {
SayHello();
return;
}
JNIEXPORT void JNICALL Java_com_aaa_bbb_ccc_HelloJNI_modIntPtr(JNIEnv *env, jobject thisObj, jint delta, jintArray intptr) {
jint *body = env->GetIntArrayElements(intptr, 0);
printf("delta = %d\n",delta);
printf("intptr = %d\n",intptr[0]);
body[0] += delta;
env->ReleaseIntArrayElements(intptr, body, 0);
printf("After mod...\n");
printf("intptr = %d\n",intptr[0]);
return;
}
JNIEXPORT void JNICALL Java_com_aaa_bbb_ccc_HelloJNI_modIntRef(JNIEnv *env, jobject thisObj, jint delta, jobject intref) {
jclass cls = env->GetObjectClass(intref);
jmethodID methodID = env->GetMethodID(cls, "getValue", "()I");
jint value = env->CallIntMethod(intref, methodID);
IntRefNative(delta, (int *)(&value));
methodID = env->GetMethodID(cls, "setValue", "(I)V");
env->CallVoidMethod(intref, methodID, value);
return;
}
HelloJNI.h
/* DO NOT EDIT THIS FILE - it is machine generated */
#include <jni.h>
/* Header for class com_aaa_bbb_ccc_HelloJNI */
#ifndef _Included_com_aaa_bbb_ccc_HelloJNI
#define _Included_com_aaa_bbb_ccc_HelloJNI
#ifdef __cplusplus
extern "C" {
#endif
/*
* Class: com_aaa_bbb_ccc_HelloJNI
* Method: sayHello
* Signature:()V
*/
JNIEXPORT void JNICALL Java_com_aaa_bbb_ccc_HelloJNI_sayHello
(JNIEnv *, jobject);
/*
* Class: com_aaa_bbb_ccc_HelloJNI
* Method: modIntPtr
* Signature: (I[I)V
*/
JNIEXPORT void JNICALL Java_com_aaa_bbb_ccc_HelloJNI_modIntPtr
(JNIEnv *, jobject, jint, jintArray);
/*
* Class: com_aaa_bbb_ccc_HelloJNI
* Method: modIntRef
* Signature: (ILcom/aaa/bbb/ccc/IntRef;)V
*/
JNIEXPORT void JNICALL Java_com_aaa_bbb_ccc_HelloJNI_modIntRef
(JNIEnv *, jobject, jint, jobject);
#ifdef __cplusplus
}
#endif
#endif
我會包括這個文件,以及任何人誰是試圖找到在java中傳入輸入/輸出或可變int參數的想法......我到處搜索了一個工作示例。
IntRef.java
package com.aaa.bbb.ccc;
public class IntRef {
private int value;
IntRef() {
value=0;
}
IntRef(int v) {
value = v;
}
/**
* Returns the integer value of this <code>IntRef</code>
*
* @return the value of the integer in native int form
*/
public int getValue() {
return value;
}
/**
* Sets the value.
*
* @param theValue The value to set
*/
public void setValue(int theValue) {
this.value = theValue;
}
}