Trouble with class

Question

I am unable to figure out what I am having trouble with this, here is the code
public class Tools3
    protected long item_number;
    protected String product_name;
    protected long units_in_stock;
    protected double price_of_each_unit;
    protected static double total_price_of_inventory;
public Tools3( long pitem_number, String pproduct_name, long punits_in_stock, double pprice_of_each_unit)
   item_number = pitem_number;
   product_name = pproduct_name;
   units_in_stock = punits_in_stock;
   price_of_each_unit = pprice_of_each_unit;
   total_price_of_inventory = punits_in_stock * pprice_of_each_unit;
// Overloaded constructor for empty balance
public Tools3()
   item_number = 0;
public void set_item_number( long pitem_number )
   item_number = pitem_number;
public void set_product_name( String pproduct_name )
   product_name = pproduct_name.toString();
public void set_units_in_stock( long punits_in_stock )
   units_in_stock = punits_in_stock;
public void set_price_of_each_unit( double pprice_of_each_unit )
   price_of_each_unit = pprice_of_each_unit;
public long get_item_number()
   return item_number;
public String get_product_name()
   return product_name;
public long get_units_in_stock()
   return units_in_stock;
public double get_price_of_each_unit()
   return price_of_each_unit;
public double calculate_total_price()
   return units_in_stock * price_of_each_unit;
public double calculate_total_price_of_inventory(Tools3[] mytools)
   double rettotal = 0;
   for (int i = 0; i < mytools.length; i++)
    rettotal = rettotal + (mytools.get_units_in_stock() * mytools.get_price_of_each_unit());
   return rettotal;
  public void sort_by_names(Tools3[] mytools)
  int a,b;
  int sortTheStrings = mytools.length - 1;
  String tempproduct_name;
  long tempitem_number;
  long tempunits_in_stock;
  double tempprice_of_each_unit;
    //need to implement a bubble sort here
    for (a = 0; a < sortTheStrings; ++a)
  for (b = 0; b < sortTheStrings; ++b)
  if(mytools.product_name.compareTo(mytools[b + 1].product_name) >0)
    //move name
    tempproduct_name = mytools.product_name;
    mytools.product_name = mytools[b+1].product_name;
    mytools[b+1].product_name = tempproduct_name;
    //move item_number
    tempitem_number = mytools.item_number;
    mytools.item_number = mytools[b+1].item_number;
    mytools[b+1].item_number = tempitem_number;
    //move units_in_stock
    tempunits_in_stock = mytools.units_in_stock;
    mytools.units_in_stock = mytools[b+1].units_in_stock;
    mytools[b+1].units_in_stock = tempunits_in_stock;
    //move price_of_each_unit
    tempprice_of_each_unit = mytools.price_of_each_unit;
    mytools.price_of_each_unit = mytools[b+1].price_of_each_unit;
    mytools[b+1].price_of_each_unit = tempprice_of_each_unit;
//end of tools3.java class

Answer 1

Results from javac
C:\Java>javac Tools3.java
Tools3.java:77: cannot find symbol
symbol  : method get_units_in_stock()
location: class Tools3[]
    rettotal = rettotal + (mytools.get_units_in_stock() * mytools.get_price_of_e
ach_unit());
                                  ^
Tools3.java:77: cannot find symbol
symbol  : method get_price_of_each_unit()
location: class Tools3[]
    rettotal = rettotal + (mytools.get_units_in_stock() * mytools.get_price_of_e
ach_unit());
                                                                 ^
Tools3.java:94: cannot find symbol
symbol  : variable product_name
location: class Tools3[]
  if(mytools.product_name.compareTo(mytools[b + 1].product_name) >0)
            ^
Tools3.java:97: cannot find symbol
symbol  : variable product_name
location: class Tools3[]
    tempproduct_name = mytools.product_name;
                              ^
Tools3.java:98: cannot find symbol
symbol  : variable product_name
location: class Tools3[]
    mytools.product_name = mytools[b+1].product_name;
           ^
Tools3.java:101: cannot find symbol
symbol  : variable item_number
location: class Tools3[]
    tempitem_number = mytools.item_number;
                             ^
Tools3.java:102: cannot find symbol
symbol  : variable item_number
location: class Tools3[]
    mytools.item_number = mytools[b+1].item_number;
           ^
Tools3.java:105: cannot find symbol
symbol  : variable units_in_stock
location: class Tools3[]
    tempunits_in_stock = mytools.units_in_stock;
                                ^
Tools3.java:106: cannot find symbol
symbol  : variable units_in_stock
location: class Tools3[]
    mytools.units_in_stock = mytools[b+1].units_in_stock;
           ^
Tools3.java:109: cannot find symbol
symbol  : variable price_of_each_unit
location: class Tools3[]
    tempprice_of_each_unit = mytools.price_of_each_unit;
                                    ^
Tools3.java:110: cannot find symbol
symbol  : variable price_of_each_unit
location: class Tools3[]
    mytools.price_of_each_unit = mytools[b+1].price_of_each_unit;
           ^
11 errors