exception - java.lang.ArrayIndexOutOfBoundsException when getting image array -

when try run following code

samplerun.java

public class samplerun {      public static void main(string[] args) {          jlibfprint jlibfprint = new jlibfprint();         jlibfprint.fp_image_data fpimg = new jlibfprint.fp_image_data();         jlibfprint.fp_image_data fpimg1 = new jlibfprint.fp_image_data() ;          try         {             file file = new file("/some/path/capture.bin");    //reads binary image file              fileinputstream fin = new fileinputstream(file);             bytearrayoutputstream bos = new bytearrayoutputstream();         byte[] buff = new byte[1024];         try         {             for(int i;(i = fin.read(buff)) !=-1;){                 bos.write(buff,0,i);                             }         }         catch (exception e) {             // todo: handle exception          }         byte[] imgbytes = bos.tobytearray();             if(file.length() == 327680)         {             h=620;             w=512;             l=327680;         }         else         {             h=320;             w=256;             l=81408;         }         fpimg.setdata(imgbytes);         fpimg.setheight(h);         fpimg.setwidth(w);         fpimg.setlength(l);             try {             fpimg1 = jlibfprint.binary_image(fpimg);     //error @ line             //return object of image structure jni code                     system.out.println("image binarized\n");         } catch (arrayindexoutofboundsexception e) {             // todo auto-generated catch block             e.printstacktrace();         }          }         catch (exception e)         {             e.printstacktrace();         }     } } 

jlibfprint.java

public class jlibfprint {      static {         system.loadlibrary("jlibfprint_jni");     }          static public class fp_image_data implements java.io.serializable{          int width;     int height;     int length;     byte data[];        public int getwidth() {         return width;     }      public void setwidth(int width) {         this.width = width;     }      public int getheight() {         return height;     }      public void setheight(int height) {         this.height = height;     }      public int getlength() {         return length;     }      public void setlength(int length) {         this.length = length;     }      public byte[] getdata() {         return data;     }      public void setdata(byte[] data) {         this.data = data;     }        public fp_image_data()     {}      public void clear()     {         width = 0;         height = 0;         length = 0;         (int = 0; < data.length; i++) data[i] = 0;     }     }  } 

jni code

jniexport jobject jnicall java_jlibfprint_jlibfprint_binary_1image(jnienv *env, jclass jcls,jobject imgobj) {     struct fp_img img;     struct fp_img *imgptr;     imgptr = &img;     jfp2cfp(env,imgobj,imgptr);   // function gets value java     fp_init();      imgptr = fp_img_binarize(imgptr);      cfp2jfp(env, imgobj, imgptr);   //this function sets value hava      fp_exit();     printf("\nlibrary closed...........");     return imgobj; } 

i following error

java.lang.arrayindexoutofboundsexception      @ jlibfprint.jlibfprint.binary_image(native method)     @ jlibfprint.samplerun.main(samplerun.java:23) 

i trying use functions of libfprint library image processing. have return jni code accessing library functions , have returned object jni java layer @ line getting error.

just thought here. hard-coding length variable 327680 or 81408 . instead try setting imgbytes.length

l = imgbytes.length; 

also please modify code below , try again :

     byte[] buff = new byte[1024];             try             {                 for(int i;(i = fin.read(buff)) !=-1;){                     bos.write(buff,0,i);                                 }                 bos.flush(); //this important             }             catch (exception e) {                e.printstacktrace();//see if error happened here              }           byte[] imgbytes = bos.tobytearray();          system.out.println(imgbytes.len);//verify has data , length greater 0 !!