Java multi-thread access Array

Public class test_runnable implements runnable {private string name; Private Static int next = 0; Private Static int Len = 10000; private final static int num = 5; private Static string STR [] = new string [Len]; Public test_runnable (string name) {super (); this. name = Name;} public test_runnable () {super (); // todo auto-generated constructor stub} public static void visit (string name) throws interruptedexception {While (hasnext ()) {system. out. println (STR [getnext ()] + "" + name); thread. sleep (1) ;}} public void run () {for (INT I = 0; I <4; I ++) {try {visit (this. name);} catch (interruptedexception e) {// todo auto-generated Catch Block E. printstacktrace () ;}}// index of the array element to be accessed next time public synchronized static int getnext () {next ++; return next-1 ;} // determine whether the access is complete. Public static Boolean hasnext () {If (next <Len) return true; return false;} public static void main (string [] ARGs) throws interruptedexception {for (INT I = 0; I <Str. length; I ++) // initialization character array {STR [I] = new string ("string" + I);} thread. sleep (1000); // create ten threads test_runnable tr [] = new test_runnable [num]; thread TD [] = new thread [num]; for (INT I = 0; I <tr. length; I ++) {tr [I] = new test_runnable ("Thread" + I); TD [I] = new thread (TR [I]);} long start = system. currenttimemillis (); thread. sleep (1000); // The thread starts executing the task for (INT I = 0; I <TD. length; I ++) {TD [I]. start ();} thread. sleep (2000); long end = system. currenttimemillis (); system. out. println (end-Start ));}}