libjava/testsuite/libjava.jni/martin.c

   1 #include <jni.h>
   2 #include "martin.h"
   3 #include <stdio.h>
   4
   5 JNIEXPORT void JNICALL
   6 Java_martin_myNative(JNIEnv* env, jobject this, jstring s)
   7 {
   8   jclass cls;
   9   jfieldID fid;
  10   jobject obj;
  11   jmethodID mid;
  12
  13   printf("From C\n");
  14   fflush(stdout);
  15
  16   cls = (*env)->FindClass(env, "java/lang/System");
  17   if (cls == 0) {
  18     printf("java/lang/System lookup failed\n");
  19     return;
  20   }
  21   fid = (*env)->GetStaticFieldID(env, cls, "out", "Ljava/io/PrintStream;");
  22   if (fid == 0) {
  23     printf("java/lang/System::out lookup failed\n");
  24     return;
  25   }
  26   obj = (*env)->GetStaticObjectField(env, cls, fid);
  27   if (obj == 0) {
  28     printf("GetStaticObjectField call failed\n");
  29     return;
  30   }
  31   cls = (*env)->GetObjectClass(env, obj);
  32   if (cls == 0) {
  33     printf("GetObjectClass(out) failed\n");
  34     return;
  35   }
  36   mid = (*env)->GetMethodID(env, cls, "println", "(Ljava/lang/String;)V");
  37   if (mid == 0) {
  38     printf("println method lookup failed\n");
  39     return;
  40   }
  41   (*env)->CallVoidMethod(env, obj, mid, s);
  42 }
  43