private MethodType(Class<?> rtype,Class<?>[] ptypes,boolean trusted){
  checkRtype(rtype);
  checkPtypes(ptypes);
  this.rtype=rtype;
  this.ptypes=trusted ? ptypes : Arrays.copyOf(ptypes,ptypes.length);
}

private MethodType ( Class < ? > rtype , Class < ? > [ ] ptypes , boolean trusted ) { checkRtype ( rtype ) ; checkPtypes ( ptypes ) ; this . rtype = rtype ; this . ptypes = trusted ? ptypes : Arrays . copyOf ( ptypes , ptypes . length ) ; }
check the given parameters for validity and store them into the final fields .
