Name: rmT116609 Date: 03/14/2002


FULL PRODUCT VERSION :
java version "1.4.0"
Java(TM) 2 Runtime Environment, Standard Edition (build 1.4.0-b92)
Java HotSpot(TM) Client VM (build 1.4.0-b92, mixed mode)

FULL OPERATING SYSTEM VERSION :
Red Hat Linux 7.2 , Redhat 7.1 on Intel

DESCRIPTION OF THE PROBLEM :
GetObjectArrayElement() broken in j2sdk1.4.0

The test consists of sending the same object (ABC) as argument a and as the first element of an ObjectArray c.

With Sun j2sdk1.4.0 (on RedHat Linux 7.2) we obtain:

object a --> obj=-1073752740 cls=134730308 fid= 34
object a --> texte='aaa'
object c[0] --> obj=134730316 cls=134730320 fid= 0
Failure2: fid(texte)=0
Exception in thread "main" java.lang.NoSuchFieldError: texte

We observe that the obj address, as returned by GetObjectArrayElement() is not the same in a and in c[0]. This is a bug.

STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
LD_LIBRARY_PATH=. ; export LD_LIBRARY_PATH
/usr/java/j2sdk1.4.0/bin/javac BugJNI.java
/usr/java/j2sdk1.4.0/bin/javah DEF gcc -c -fPIC *.c
gcc -shared -o libBugJNI.so *.o
/usr/java/j2sdk1.4.0/bin/java -Xcheck:jni ABCDemo

EXPECTED VERSUS ACTUAL BEHAVIOR :
GetObjectArrayElement() broken in j2sdk1.4.0

The test consists of sending the same object (ABC) as argument a and as the first element of an ObjectArray c.

With Kaffe, we obtain:

object a --> obj=136050432 cls=136032328 fid= 136050456
object a --> texte='aaa'
entering in native exec n=2
object c[0] --> obj=136050432 cls=136032328 fid= 136050456
object c[0] --> texte='aaa'
object c[1] --> obj=136050840 cls=136032328 fid= 136050456
object c[1] --> texte='bbb'

We observe that the obj address, as returned by GetObjectArrayElement()
is the same in a and in c[0]. This is OK.

With Sun j2sdk1.4.0 (on RedHat Linux 7.2) we obtain:

object a --> obj=-1073752740 cls=134730308 fid= 34
object a --> texte='aaa'
object c[0] --> obj=134730316 cls=134730320 fid= 0
Failure2: fid(texte)=0
Exception in thread "main" java.lang.NoSuchFieldError: texte

We observe that the obj address, as returned by GetObjectArrayElement() is not the same in a and in c[0]. This is a bug.

ERROR MESSAGES/STACK TRACES THAT OCCUR :
Failure2: fid(texte)=0
Exception in thread "main" java.lang.NoSuchFieldError: texte

This bug can be reproduced always.

---------- BEGIN SOURCE -----------------------------------------------
== file BugJNI.java ==

class ABC {
  String texte;
}
class ABCDemo {
  public static void main(String args[]) {
    ABC a = new ABC();
    ABC b = new ABC();
    a.texte = "aaa";
    b.texte = "bbb";
    ABC[] c = {a, b};
    DEF my_def = new DEF();
    my_def.exec(a, c);
  }
}
class DEF {
  static {
    System.loadLibrary("BugJNI");
  }
  public native void exec(ABC a, ABC[] c);

== file BugJNI.c ==

#include <jni.h>
#include <stdio.h>
#include "DEF.h"

JNIEXPORT void JNICALL Java_DEF_exec(JNIEnv *env, jobject this, jobject a, jobjectArray c) {
   jclass cls = (*env)->GetObjectClass(env, a);
   long i;
   jfieldID fid;
   const char *str;
   jint n;
   jstring jstr;
   
   /* recover the text in object a */
   fid = (*env)->GetFieldID(env, cls, "texte", "Ljava/lang/String;");
   printf("object a --> obj=%d cls=%d fid= %d\n",a,cls,fid);
   if (fid == 0) {
     printf("Failure1: fid(texte)=0\n");
     return;
   }
   jstr = (*env)->GetObjectField(env, a, fid);
   str = (*env)->GetStringUTFChars(env, jstr, 0);
   printf("object a --> texte='%s'\n",str);
   (*env)->ReleaseStringUTFChars(env, jstr, str);
   
   /* recover the text in object c[i] */
   n = (*env)->GetArrayLength(env, c);
   for (i = 0; i < n; ++i) {
     jobject obj = (*env)->GetObjectArrayElement(env, c, i);
     jclass cls = (*env)->GetObjectClass(env, obj);
     fid = (*env)->GetFieldID(env, cls, "texte", "Ljava.lang.String;");
     printf("object c[%d] --> obj=%d cls=%d fid= %d\n",i,obj,cls,fid);
     if (fid == 0) {
       printf("Failure2: fid(texte)=0\n");
       return;
     }
     jstr = (*env)->GetObjectField(env, obj, fid);
     str = (*env)->GetStringUTFChars(env, jstr, 0);
     printf("object c[%d] --> texte='%s'\n",i,str);
     (*env)->ReleaseStringUTFChars(env, jstr, str);
   }
}

}

---------- END SOURCE ----------

(Review ID: 144135)
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