public static synchronized Type tArray(Type elem){
  String sig=new String(SIG_ARRAY + elem.getTypeSignature());
  Type t=(Type)typeHash.get(sig);
  if (t == null) {
    t=new ArrayType(sig,elem);
  }
  return t;
}

public static synchronized Type tArray ( Type elem ) { String sig = new String ( SIG_ARRAY + elem . getTypeSignature ( ) ) ; Type t = ( Type ) typeHash . get ( sig ) ; if ( t == null ) { t = new ArrayType ( sig , elem ) ; } return t ; }
create an array type .
