out of memory - How do I solve OutOfMemoryError: Java heap space -

i getting following error on commented line:

"outofmemoryerror: java heap space"  

the data.bin file huge error expected. question how around error? have seen stuff -xmx1024m or similar, don't know how run using jgrasp compiler

 try {     randomaccessfile data = new randomaccessfile("data.bin","rws");     long l = data.length();     long recs = l / 1024;     long cnt = 0;     byte []b = new byte[1024];      while(cnt < recs){        cnt++;        data.readfully(b);        byte []key = arrays.copyofrange(b, 0, 24);        byte []value = arrays.copyofrange(b, 24, 1024);        en = new tentry<string, string>(new string(key), new string(value));//error        lst.add(en);     } 

you can increase heap/stack size using following commands:

-xms<size>        set initial java heap size -xmx<size>        set maximum java heap size -xss<size>        set java thread stack size 

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