Question

我在使用Java和JNI接口时遇到问题。我已经建立了一个连接到某些网站并打印内容并将内容发送到jni c ++的系统。但是我有一些问题。当我尝试将BufferedReader字符串发送给jni时，我得到了一个Java空指针异常

所以你能帮我吗！谢谢！ C ++：

#include </jdk1.8.0_191/include/jni.h>
#include "/build/classes/crawlhttpsmemoryc_Crawlhttpsmemoryc.h"





JNIEXPORT jstring JNICALL Java_crawlhttpsmemoryc_Crawlhttpsmemoryc_seaubsiteco
  (JNIEnv * env, jobject xtest, jstring xsd) {

   std::string strServiceIp(env->GetStringUTFChars(xsd, NULL));

    std::cout << "du c++" << strServiceIp;

  }

还有java：

 public static void main(String[] args) throws MalformedURLException, IOException {

        String httpsURL = "https://gnu.org";
        URL myUrl = new URL(httpsURL);
        HttpsURLConnection conn = (HttpsURLConnection)myUrl.openConnection();

conn.setRequestProperty("Content-Language", "en-US");


        InputStream is = conn.getInputStream();
        System.out.println(org.apache.commons.io.IOUtils.toString(is));

        InputStreamReader isr = new InputStreamReader(is);
        BufferedReader br = new BufferedReader(isr);

        StringBuffer sb = new StringBuffer();
        String inputLine;
String x = "";
StringBuilder xbuf = new StringBuilder();
        while ((inputLine = br.readLine()) != null) {
        xbuf.append(inputLine);
        }
 x= xbuf.toString();
    new Crawlhttpsmemoryc().seaubsiteco(x);

堆栈跟踪：

 Exception in thread "main" java.lang.NullPointerException at crawlhttpsmemoryc.Crawlhttpsmemoryc.seaubsiteco(Native Method)

使用jni的长字符串上的NullPointer

0 个答案: