lab4 some minor fixes

src/frames/FrameShipsCollection.java

@@ -5,15 +5,15 @@ import javax.swing.border.StrokeBorder;
 import java.awt.*;
 import java.io.IOException;
 import java.util.ArrayList;
+import java.util.LinkedList;
 import java.util.Objects;
 
 import drawing_objects.DrawingShip;
 import generics.ShipsGenericStorage;
-import generics.TrashCollection;
 
 public class FrameShipsCollection extends JFrame {
     private final ShipsGenericStorage storage;
-    TrashCollection<DrawingShip> trashCollection = new TrashCollection<>();
+    LinkedList<DrawingShip> trashCollection = new LinkedList<>();
     private JComponent pictureBoxCollection;
     private TextField textFieldNumber;
     private TextField textFieldStorageName;
@@ -45,6 +45,7 @@ public class FrameShipsCollection extends JFrame {
         pictureBoxCollection.setPreferredSize(new Dimension(700, 450));
         JButton buttonAddShip = new JButton("Добавить корабль");
         textFieldNumber = new TextField();
+        textFieldNumber.setText("0");
         JButton buttonRemoveShip = new JButton("Удалить корабль");
         JButton buttonRefreshCollection = new JButton("Обновить коллекцию");
         JButton buttonAddSet = new JButton("Добавить набор");
@@ -167,7 +168,7 @@ public class FrameShipsCollection extends JFrame {
         });
     }
     private void buttonRemoveShipClick(){
-        if (listStorages.getSelectedIndex() == -1)
+        if (listStorages.getSelectedIndex() == -1 || Objects.equals(textFieldNumber.getText(), "") || textFieldNumber.getText() == null)
             return;
         var obj = storage.getSet(listStorages.getSelectedValue());
         if (obj == null)
@@ -187,7 +188,7 @@ public class FrameShipsCollection extends JFrame {
         pictureBoxCollection.repaint();
     }
     private void buttonTrashClick(){
-        if(trashCollection.getSize() == 0)
+        if(trashCollection.peek() == null)
             return;
         FrameBattleship form;
         try {

src/generics/TrashCollection.java

@@ -1,21 +0,0 @@
-package generics;
-
-import java.util.LinkedList;
-
-public class TrashCollection<T> {
-    LinkedList<T> list;
-    public TrashCollection(){
-        list = new LinkedList<>();
-    }
-    public int getSize(){
-        return list.size();
-    }
-    public void add(T ship){
-        list.add(ship);
-    }
-    public T pop(){
-        if(list.size() == 0)
-            return null;
-        return list.pop();
-    }
-}