how to convert an int array to a char array

[andrea_]

I've got a problem: I must use an int java array in a C code. Using JNI
i wrote this code:

jsize len = (*env)->GetArrayLength(env, payload); //payload is the
name of java array
jint *body = (*env)->GetIntArrayElements(env, payload, 0);
int cpayload [len]; // C array
int i;
for (i=0; i<len; i++)
{
cpayload[i] = body[i]; // copying the java array value into C array
value
}

input.d_ip=0;
input.data_size=len;
input.data=(u_char)*body; //here there is the error

the compiler says this:
warning: assignment makes pointer from integer without a cast

P.S. data is define in this way:
u_char *data;

[Zara]

andrea_ wrote:

I've got a problem: I must use an int java array in a C code. Using JNI
i wrote this code:

jsize len = (*env)->GetArrayLength(env, payload); //payload is the
name of java array
jint *body = (*env)->GetIntArrayElements(env, payload, 0);
int cpayload [len]; // C array
int i;
for (i=0; i<len; i++)
{
cpayload[i] = body[i]; // copying the java array value into C array
value
}

input.d_ip=0;
input.data_size=len;
input.data=(u_char)*body; //here there is the error

the compiler says this:
warning: assignment makes pointer from integer without a cast

P.S. data is define in this way:
u_char *data;

The cast is wrong; write:

input.data=(u_char *)body;

[Flash Gordon]

Zara wrote:

andrea_ wrote:

I've got a problem: I must use an int java array in a C code. Using JNI
i wrote this code:

jsize len = (*env)->GetArrayLength(env, payload); //payload is the
name of java array
jint *body = (*env)->GetIntArrayElements(env, payload, 0);
<snip>
input.data=(u_char)*body; //here there is the error

the compiler says this:
warning: assignment makes pointer from integer without a cast

P.S. data is define in this way:
u_char *data;

The cast is wrong; write:

input.data=(u_char *)body;

That will get rid of the warning and, assuming u_char is a typedef for
unsigned char is completely valid as far as C is concerned. However I
would suggest the OP ask somewhere where the JNI is on topic to see if
this is the right was to access a Java int array. Since the J in JNI
stands for Java I would suggest a group with java in the name, possible
comp.lang.java.programmer, but check *their* FAQ, charter and a load of
posts to see what goes on there before posting.
--
Flash Gordon
Living in interesting times.
Although my email address says spam, it is real and I read it.