ЛР3. Задание 2

src/tse/LR_3.java

@@ -22,6 +22,7 @@ public class LR_3 implements ILabRab {
                 LR_3_Tasks.getInstance().task1();
                 break;
             case 1:
+                LR_3_Tasks.getInstance().task2();
                 break;
             case 2:
                 break;

src/tse/lr2/Ellipse.java

@@ -29,6 +29,14 @@ public class Ellipse implements Serializable {
         points = Arrays.copyOf(ellipse.points, POINTS);
     }
     
+    public Point[] getPoints() {
+        return points;
+    }
+    
+    public void setPoint(int index, Point point) {
+        points[index] = point;
+    }
+    
     public static Point getCenterPoint(Ellipse ellipse) {
         return ellipse.getCenterPoint();
     }

src/tse/lr3/LR_3_Tasks.java

@@ -2,11 +2,15 @@ package tse.lr3;
 
 import tse.lr2.*;
 import java.awt.Point;
+import java.io.BufferedReader;
+import java.io.BufferedWriter;
 import java.io.FileInputStream;
 import java.io.FileOutputStream;
 import java.io.IOException;
+import java.io.InputStreamReader;
 import java.io.ObjectInputStream;
 import java.io.ObjectOutputStream;
+import java.io.OutputStreamWriter;
 import java.util.ArrayList;
 import java.util.List;
 
@@ -42,7 +46,9 @@ public class LR_3_Tasks {
 
     public void task2() {
         makeObjects();
+        boolean needCreateCSV = false;
         ArrayList<Ellipse> ellipses = new ArrayList<>();
+        if (needCreateCSV) {
             ellipses.add(ellipse1);
             ellipses.add(ellipse2);
             ellipses.add(ellipse3);
@@ -51,6 +57,32 @@ public class LR_3_Tasks {
             printList(ellipses);
         }
         
+        try {
+            // Создаём при необходимости CSV-файл.
+            if (needCreateCSV) {
+                writeToCSV("ellipses.csv", ellipses);
+                ellipses = null;
+            }
+            
+            // Читаем список из CSV
+            ellipses = (ArrayList) readFromCSV("ellipses.csv");
+            System.out.println("Прочитано из csv");
+            printList(ellipses);
+            
+            // Сериализуем список в бинарный файл
+            serialize("t2_list.ser", ellipses);
+            ellipses = null;
+            
+            // Десериализуем список из файла
+            ellipses = (ArrayList) deserialize("t2_list.ser");
+            System.out.println("Десериализовано из бинарного файла");
+            printList(ellipses);
+            System.out.println("Готово");
+        } catch (IOException ex) {
+            ex.printStackTrace();
+        }
+    }
+    
     public void task5() {
         makeObjects();
     }
@@ -96,10 +128,79 @@ public class LR_3_Tasks {
         return object;
     }
     
+    private void writeToCSV(String filename, List<Ellipse> list) throws IOException {
+        BufferedWriter writer = new BufferedWriter(
+                new OutputStreamWriter(new FileOutputStream(filename), "UTF-8")
+        );
+        writer.write("Класс,X1,Y1,X2,Y2,X3,Y3,X4,Y4");
+        for (Ellipse ellipse : list) {
+            writer.newLine();
+            writeCsvLine(writer, ellipse);
+        }
+        writer.flush();
+        writer.close();
+    }
+    
+    private void writeCsvLine(BufferedWriter writer, Ellipse ellipse) throws IOException {
+        final String SEPARATOR = ",";
+        writer.write(ellipse.getClass().getName());
+        Point[] points = ellipse.getPoints();
+        for (Point point : points) {
+            writer.write(SEPARATOR);
+            writer.write(String.valueOf(point.x));
+            writer.write(SEPARATOR);
+            writer.write(String.valueOf(point.y));
+        }
+    }
+    
+    private List<Ellipse> readFromCSV(String filename) throws IOException {
+        List<Ellipse> list = new ArrayList<>();
+        BufferedReader reader = new BufferedReader(
+                new InputStreamReader( new FileInputStream(filename), "UTF-8" )
+        );
+        reader.readLine(); // Класс,X1,Y1,X2,Y2,X3,Y3,X4,Y4
+        String line;
+        while ( (line = reader.readLine()) != null ) {
+            Ellipse ellipse = null;
+            try {
+                ellipse = readFromCsvLine(line);
+            } catch (RuntimeException ex) {
+                System.out.println(ex.toString());
+            }
+            if (ellipse != null) list.add(ellipse);
+        }
+        reader.close();
+        return list;
+    }
+    
+    private Ellipse readFromCsvLine(String line) {
+        final int POINTS_COUNT = 4;
+        if (line.isEmpty()) throw new RuntimeException("Пустая строка");
+        String[] params = line.split(",");
+        if (params.length < 9) throw new RuntimeException("Неверное количество параметров");
+        
+        final int[] coords = new int[POINTS_COUNT * 2];
+        for (int i = 0; i < coords.length; i++) {
+            coords[i] = Integer.parseInt(params[i + 1]);
+        }
+        
+        Ellipse out;
+        if (params[0].equalsIgnoreCase(Circle.class.getName())) {
+            out = new Circle();
+        } else {
+            out = new Ellipse();
+        }
+        for (int i = 0; i < POINTS_COUNT; i++) {
+            out.setPoint(i, new Point(coords[i * 2], coords[i * 2 + 1]));
+        }
+        return out;
+    }
+    
     private void printList(List<Ellipse> list) {
         for (int i = 0; i < list.size(); i++) {
             Ellipse ellipse = list.get(i);
-            System.out.println( String.format("%2d. %f", i + 1, ellipse.getSquare()) );
+            System.out.println( String.format("%2d. %s: Площадь %f\n", i + 1,
+                    ellipse.getClass().getName(), ellipse.getSquare()) );
         }
     }