AB8/5

angabe/Aufgabenblatt8.md

@@ -1,7 +1,7 @@
 # Aufgabenblatt 8
 
 ## Allgemeine Anmerkungen
-Ihre Lösung für dieses Aufgabenblatt ist bis Dienstag, 13.6., 11h durch `git commit` und `git push` 
+Ihre Lösung für dieses Aufgabenblatt ist bis Montag, 13.6., 11h durch `git commit` und `git push`
 abzugeben.
 Wenn Sie zusätzlich zu den gefragten Klassen und Interfaces weitere Klassen oder
 Interfaces definieren, achten Sie darauf, dass die Klassennamen mit `My` beginnen, um Konflikte
@@ -20,7 +20,7 @@ Validierung, Exceptions (S. 110-123).
 - [states](../states) ist ein Verzeichnis, in dem mehrere Dateien mit der Endung `.txt`
  mitgeliefert werden. Diese enthalten Daten von je einem Himmelskörper sowie dessen Positionen und
  Geschwindigkeitsvektoren für alle Tage der Jahre 2019-2021. Die Angaben sind wie gewohnt in
- kartesischen Koordinaten, wobei die Sonne den Urspung des Koordinatensystems bildet und die 
+ kartesischen Koordinaten, wobei die Sonne den Ursprung des Koordinatensystems bildet und die
  Ekliptik die x-y-Ebene darstellt. Die Daten stammen von [https://ssd.jpl.nasa.gov/horizons.cgi#top](https://ssd.jpl.nasa.gov/horizons.cgi#top).
 
     **ACHTUNG**: Die Werte sind in km bzw. km/sec angegeben!

src/Aufgabe8Test.java

@@ -1,100 +1,50 @@
+import org.junit.jupiter.api.Test;
 
-import java.util.HashSet;
 import java.util.NoSuchElementException;
 
+import static org.junit.jupiter.api.Assertions.*;
+
 public class Aufgabe8Test {
 
-    public static void main(String[] args) {
-
-        /* //TODO: uncomment for testing
-
+    @Test
+    public void testEP2() {
         MassiveForceTreeMap map = new MassiveForceTreeMap();
         NamedBody mars;
 
-        map.put(new NamedBody("Oumuamua", 8e6, new Vector3(0, 0, 0), new Vector3(0, 0, 0)),
-                new Vector3(0, 0, 0));
-        map.put(new NamedBody("Earth", 5.972E24, new Vector3(0, 0, 0), new Vector3(0, 0, 0)),
-                new Vector3(0, 0, 0));
-        map.put(new NamedBody("Moon", 7.349E22, new Vector3(0, 0, 0), new Vector3(0, 0, 0)),
-                new Vector3(0, 0, 0));
-        map.put(mars = new NamedBody("Mars", 6.41712E23, new Vector3(0, 0, 0),
-                        new Vector3(0, 0, 0)),
-                new Vector3(0, 0, 0));
-        map.put(new NamedBody("Deimos", 1.8E20, new Vector3(0, 0, 0), new Vector3(0, 0, 0)),
-                new Vector3(0, 0, 0));
-        map.put(new NamedBody("Phobos", 1.08E20, new Vector3(0, 0, 0), new Vector3(0, 0, 0)),
-                new Vector3(0, 0, 0));
-        map.put(new NamedBody("Mercury", 3.301E23, new Vector3(0, 0, 0), new Vector3(0, 0, 0)),
-                new Vector3(0, 0, 0));
-        map.put(new NamedBody("Venus", 4.86747E24, new Vector3(0, 0, 0), new Vector3(0, 0, 0)),
-                new Vector3(0, 0, 0));
-        map.put(new NamedBody("Vesta", 2.5908E20, new Vector3(0, 0, 0), new Vector3(0, 0, 0)),
-                new Vector3(0, 0, 0));
-        map.put(new NamedBody("Pallas", 2.14E20, new Vector3(0, 0, 0), new Vector3(0, 0, 0)),
-                new Vector3(0, 0, 0));
-        map.put(new NamedBody("Hygiea", 8.32E19, new Vector3(0, 0, 0), new Vector3(0, 0, 0)),
-                new Vector3(0, 0, 0));
-        map.put(new NamedBody("Ceres", 9.394E20, new Vector3(0, 0, 0), new Vector3(0, 0, 0)),
-                new Vector3(0, 0, 0));
+        map.put(new NamedBody("Oumuamua", 8e6, new Vector3(), new Vector3()), new Vector3());
+        map.put(new NamedBody("Earth", 5.972E24, new Vector3(), new Vector3()), new Vector3());
+        map.put(new NamedBody("Moon", 7.349E22, new Vector3(), new Vector3()), new Vector3());
+        map.put(mars = new NamedBody("Mars", 6.41712E23, new Vector3(), new Vector3()), new Vector3());
+        map.put(new NamedBody("Deimos", 1.8E20, new Vector3(), new Vector3()), new Vector3());
+        map.put(new NamedBody("Phobos", 1.08E20, new Vector3(), new Vector3()), new Vector3());
+        map.put(new NamedBody("Mercury", 3.301E23, new Vector3(), new Vector3()), new Vector3());
+        map.put(new NamedBody("Venus", 4.86747E24, new Vector3(), new Vector3()), new Vector3());
+        map.put(new NamedBody("Vesta", 2.5908E20, new Vector3(), new Vector3()), new Vector3());
+        map.put(new NamedBody("Pallas", 2.14E20, new Vector3(), new Vector3()), new Vector3());
+        map.put(new NamedBody("Hygiea", 8.32E19, new Vector3(), new Vector3()), new Vector3());
+        map.put(new NamedBody("Ceres", 9.394E20, new Vector3(), new Vector3()), new Vector3());
 
+        assertEquals(12, map.size());
 
-        System.out.println("Test1:");
         MassiveIterator iterator = map.getKeys().iterator();
-        int count = 0;
-        while(iterator.hasNext()) {
+        int count;
+        for (count = 0; iterator.hasNext(); count++) {
             if (iterator.next().equals(mars)) {
                 iterator.remove();
             }
-            count++;
         }
-        testValue(count, 12);
-        testValue(map.getKeys().size(), 11);
-        testValue(map.getKeys().contains(mars), false);
+        assertEquals(12, count);
+        assertEquals(11, map.getKeys().size());
+        assertEquals(11, map.size());
+        assertFalse(map.getKeys().contains(mars));
 
-        System.out.println("Test2:");
-        try {
-            iterator.next();
-            // this statement must not be reached
-            testValue(true, false);
-        } catch (NoSuchElementException e) {
-            testValue(true, true);
-        }
+        assertThrows(NoSuchElementException.class, iterator::next);
 
-        System.out.println("Test3:");
         iterator = map.getKeys().iterator();
         while (iterator.hasNext()) {
             iterator.next();
             iterator.remove();
         }
-        testValue(map.getKeys().size(),0);
-
-        */ //TODO: uncomment
-    }
-
-    public static void testComparison(Object first, Object second, boolean expected) {
-        boolean real = first == second;
-
-        if (real == expected) {
-            System.out.println("Successful comparison");
-        } else {
-            System.out.println("Comparison NOT successful! Expected value: " + expected + " / Given value: " + real);
+        assertEquals(0, map.getKeys().size());
     }
 }
-
-    public static void testValue(Object given, Object expected) {
-        if (given == expected) {
-            System.out.println("Successful test");
-        } else {
-            System.out.println("Test NOT successful! Expected value: " + expected + " / Given value: " + given);
-        }
-    }
-
-    public static void testValue(double given, double expected) {
-        if (given < expected + (expected + 1) / 1e12 && given > expected - (expected + 1) / 1e12) {
-            System.out.println("Successful test");
-        } else {
-            System.out.println("Test NOT successful! Expected value: " + expected + " / Given value: " + given);
-        }
-    }
-
-}

src/Body.java

@@ -20,6 +20,19 @@ public class Body implements Massive {
         this.currentMovement = new Vector3(other.currentMovement);
     }
 
+    public Body(double mass) {
+        this(mass, new Vector3(), new Vector3());
+    }
+
+    public Body() {
+        this(0);
+    }
+
+    public void setState(Vector3 position, Vector3 velocity) {
+        this.massCenter = new Vector3(position);
+        this.currentMovement = new Vector3(velocity);
+    }
+
     /**
      * Returns the distance between the mass centers of this body and the specified body 'b'.
      */

src/BodyForceTreeMap.java

@@ -87,14 +87,14 @@ public class BodyForceTreeMap {
     }
 
     private String toString(Item item) {
-        String s = "";
+        StringBuilder s = new StringBuilder();
         if (item == null) {
-            return s;
+            return s.toString();
         }
-        s += this.toString(item.right);
-        s += String.format("{%s: %s}\n", item.key, item.value);
-        s += this.toString(item.left);
-        return s;
+        s.append(this.toString(item.right));
+        s.append(String.format("{%s: %s}\n", item.key, item.value));
+        s.append(this.toString(item.left));
+        return s.toString();
     }
 
     /**

src/HierarchicalSystem.java

@@ -1,5 +1,7 @@
 import codedraw.CodeDraw;
 
+import java.util.NoSuchElementException;
+
 /**
  * A cosmic system that is composed of a central named body (of type 'NamedBodyForcePair')
  * and an arbitrary number of subsystems (of type 'CosmicSystem') in its orbit.
@@ -136,6 +138,7 @@ public class HierarchicalSystem implements CosmicSystem, MassiveIterable {
 
             @Override
             public Massive next() {
+                if (!hasNext()) throw new NoSuchElementException();
                 if (cur != null && cur.hasNext()) return cur.next();
 
                 while (i < all.length) {

src/MassiveForceTreeMap.java

@@ -1,5 +1,7 @@
 import codedraw.CodeDraw;
 
+import java.util.NoSuchElementException;
+
 /**
  * A map that associates an object of 'Massive' with a Vector3. The number of key-value pairs
  * is not limited.
@@ -86,14 +88,14 @@ public class MassiveForceTreeMap implements MassiveSet {
     }
 
     private String toString(Item item) {
-        String s = "";
+        StringBuilder s = new StringBuilder();
         if (item == null) {
-            return s;
+            return s.toString();
         }
-        s += this.toString(item.right);
-        s += String.format("{%s: %s}\n", item.key, item.value);
-        s += this.toString(item.left);
-        return s;
+        s.append(this.toString(item.right));
+        s.append(String.format("{%s: %s}\n", item.key, item.value));
+        s.append(this.toString(item.left));
+        return s.toString();
     }
 
     /**
@@ -120,25 +122,36 @@ public class MassiveForceTreeMap implements MassiveSet {
     @Override
     public MassiveIterator iterator() {
         return new MassiveIterator() {
+            private Item last = null;
             private Item next = root.getLeftLeaf();
 
             @Override
             public Massive next() {
-                if (next == null) return null;
-                Massive m = next.key;
+                if (!hasNext()) throw new NoSuchElementException();
+
+                last = next;
                 Item newNext = (next.right != null) ? next.right.getLeftLeaf() : next.parent;
+
                 while (newNext != null && newNext.right == next) {
                     next = newNext;
                     newNext = newNext.parent;
                 }
+
                 next = newNext;
-                return m;
+                return last.key;
             }
 
             @Override
             public boolean hasNext() {
                 return next != null;
             }
+
+            @Override
+            public void remove() {
+                if (last == null) throw new IllegalStateException();
+                removeItem(last);
+                last = null;
+            }
         };
     }
 
@@ -152,18 +165,7 @@ public class MassiveForceTreeMap implements MassiveSet {
         Item item = root;
         while (item != null) {
             if (item.key.equals(element)) {
-                Item newP = null;
-                if (item.left != null) {
-                    newP = item.left.getRightLeaf();
-                } else if (item.right != null) {
-                    newP = item.right.getLeftLeaf();
-                }
-                if (item.parent.left == item) {
-                    item.parent.setLeft(newP);
-                } else {
-                    item.parent.setRight(newP);
-                }
-                size--;
+                removeItem(item);
                 return;
             } else if (item.key.mass() > element.mass()) {
                 item = item.left;
@@ -171,6 +173,44 @@ public class MassiveForceTreeMap implements MassiveSet {
                 item = item.right;
             }
         }
+        throw new NoSuchElementException();
+    }
+
+    private void removeItem(Item item) {
+        size--;
+        Item newP = null;
+
+        if (item.left != null) {
+            newP = item.left.getRightLeaf();
+            if (newP != item.left) {
+                newP.parent.setRight(newP.left);
+                newP.setLeft(item.left);
+            }
+            newP.setRight(item.right);
+        } else if (item.right != null) {
+            newP = item.right.getLeftLeaf();
+            if (newP != item.right) {
+                newP.parent.setLeft(newP.right);
+                newP.setRight(item.right);
+            }
+            newP.setLeft(item.left);
+        }
+
+        if (newP == null) {
+            root = null;
+            return;
+        }
+
+        if (item.parent != null) {
+            if (item.parent.left == item) {
+                item.parent.setLeft(newP);
+            } else {
+                item.parent.setRight(newP);
+            }
+        } else {
+            root = newP;
+            newP.parent = null;
+        }
     }
 
     @Override
@@ -217,17 +257,13 @@ public class MassiveForceTreeMap implements MassiveSet {
 
         public Item getLeftLeaf() {
             Item cur = this;
-            while (cur.left != null) {
-                cur = cur.left;
-            }
+            while (cur.left != null) cur = cur.left;
             return cur;
         }
 
         public Item getRightLeaf() {
             Item cur = this;
-            while (cur.right != null) {
-                cur = cur.right;
-            }
+            while (cur.right != null) cur = cur.right;
             return cur;
         }
     }

src/MassiveLinkedList.java

@@ -1,4 +1,5 @@
 import java.util.Iterator;
+import java.util.NoSuchElementException;
 
 /**
  * A list of massive objects implemented as a linked list.
@@ -184,6 +185,7 @@ public class MassiveLinkedList implements MassiveIterable {
 
             @Override
             public Massive next() {
+                if (!hasNext()) throw new NoSuchElementException();
                 if (!yieldedFirst) {
                     yieldedFirst = true;
                 } else {

src/NamedBody.java

@@ -1,43 +1,41 @@
-import codedraw.CodeDraw;
 
-public class NamedBody implements Massive {
+public class NamedBody extends Body {
 
     private final String name;
-    private final Body body;
 
     /**
      * Initializes this with name, mass, current position and movement.
      */
     public NamedBody(String name, double mass, Vector3 massCenter, Vector3 currentMovement) {
-        this(name, new Body(mass, massCenter, currentMovement));
+        super(mass, massCenter, currentMovement);
+        this.name = name;
+    }
+
+    public NamedBody(String name, double mass) {
+        super(mass);
+        this.name = name;
+    }
+
+    public NamedBody(String name) {
+        super();
+        this.name = name;
     }
 
     public NamedBody(String name, Body body) {
+        super(body);
         this.name = name;
-        this.body = body;
     }
 
     public NamedBody(NamedBody other) {
-        this(other.name, new Body(other.body));
+        super(other);
+        this.name = other.name;
     }
 
     /**
      * Returns the name of the body.
      */
     public String getName() {
-        return name;
-    }
-
-    public Body getBody() {
-        return body;
-    }
-
-    public Vector3 getMassCenter() {
-        return body.getMassCenter();
-    }
-
-    public double getMass() {
-        return body.getMass();
+        return this.name;
     }
 
     /**
@@ -66,14 +64,4 @@ public class NamedBody implements Massive {
     public String toString() {
         return this.getName();
     }
-
-    @Override
-    public void move(Vector3 force) {
-        body.move(force);
-    }
-
-    @Override
-    public void draw(CodeDraw cd) {
-        body.draw(cd);
-    }
 }

src/NamedBodyForcePair.java

@@ -30,7 +30,7 @@ public class NamedBodyForcePair implements CosmicSystem {
     }
 
     public Body getBody() {
-        return body.getBody();
+        return body;
     }
 
     /**
@@ -72,13 +72,13 @@ public class NamedBodyForcePair implements CosmicSystem {
 
     @Override
     public void addForceTo(CosmicSystem cs) {
-        cs.addForceFrom(body.getBody());
+        cs.addForceFrom(body);
     }
 
     @Override
     public BodyLinkedList getBodies() {
         BodyLinkedList list = new BodyLinkedList();
-        list.addFirst(body.getBody());
+        list.addFirst(body);
         return list;
     }
 

src/ReadDataUtil.java

@@ -1,27 +1,127 @@
 import java.io.*;
+import java.util.Scanner;
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
 
 public class ReadDataUtil {
 
-    // Reads the position and velocity vector on the specified 'day' from the file with the
-    // specified 'path', and sets position and current velocity of 'b' accordingly. If
-    // successful the method returns 'true'. If the specified 'day' was not found in the file,
-    // 'b' is unchanged and the method returns 'false'.
-    // The file format is validated before reading the state.
-    // Lines before the line "$$SOE" and after the line "$$EOE" the are ignored. Each line of the
-    // file between the line "$$SOE" and the line "$$EOE" is required to have the following format:
-    // JDTDB, TIME, X, Y, Z, VX, VY, VZ
-    // where JDTDB is interpretable as a 'double' value, TIME is a string and X, Y, Z, VX, VY and
-    // VZ are interpretable as 'double' values. JDTDB can be ignored. The character ',' must only
-    // be used as field separator. If the file is not found, an exception of the class
-    // 'StateFileNotFoundException' is thrown. If it does not comply with the format described
-    // above, the method throws an exception of the class 'StateFileFormatException'. Both
-    // exceptions are subtypes of 'IOException'.
-    // Precondition: b != null, path != null, day != null and has the format YYYY-MM-DD.
-    public static boolean readConfiguration(NamedBody b, String path, String day)
-            throws IOException {
+    private static final Pattern LINE_FORMAT = Pattern.compile("^\\d+(\\.\\d+)?, *[A-Za-z \\d:.-]+(, *[-+]?\\d+(\\.\\d+)?([eE][+-]?\\d+)?){6}, *$");
+    private static final Pattern DATE_COLUMN_FORMAT = Pattern.compile("^A\\.D\\. (?<year>\\d{4})-(?<month>[A-Z][a-z]{2})-(?<day>[0-3]\\d) \\d{2}:\\d{2}:\\d{2}(\\.\\d+)?$");
+    private static final Pattern DATE_FORMAT_YYYY_MMM_DD = Pattern.compile("^(?<year>\\d{4})-(?<month>[A-Z][a-z]{2})-(?<day>[0-3]\\d)$");
 
-            // TODO: implement this method.
+    /**
+     * Reads the position and velocity vector on the specified 'day' from the file with the
+     * specified 'path', and sets position and current velocity of 'b' accordingly. If
+     * successful the method returns 'true'. If the specified 'day' was not found in the file,
+     * 'b' is unchanged and the method returns 'false'.
+     * The file format is validated before reading the state.
+     * Lines before the line "$$SOE" and after the line "$$EOE" the are ignored. Each line of the
+     * file between the line "$$SOE" and the line "$$EOE" is required to have the following format:
+     * JDTDB, TIME, X, Y, Z, VX, VY, VZ
+     * where JDTDB is interpretable as a 'double' value, TIME is a string and X, Y, Z, VX, VY and
+     * VZ are interpretable as 'double' values. JDTDB can be ignored. The character ',' must only
+     * be used as field separator. If the file is not found, an exception of the class
+     * 'StateFileNotFoundException' is thrown. If it does not comply with the format described
+     * above, the method throws an exception of the class 'StateFileFormatException'. Both
+     * exceptions are subtypes of 'IOException'.
+     * Precondition: b != null, path != null, day != null and has the format YYYY-MM-DD.
+     */
+    public static boolean readConfiguration(NamedBody b, String path, String day) throws IOException {
+        State state = State.Pre;
+        try (BufferedInputStream in = new BufferedInputStream(new FileInputStream(path))) {
+            Scanner lines = new Scanner(in);
+            long lineNum = 0;
+            while (lines.hasNextLine() && state != State.Post) {
+                lineNum++;
+                String line = lines.nextLine();
+                State nextState = state.next(line);
+
+                if (state == State.In && nextState == State.In) {
+                    Matcher m = LINE_FORMAT.matcher(line);
+                    if (!m.matches()) {
+                        throw new StateFileFormatException(path, lineNum);
+                    }
+
+                    String[] rows = line.split(", *");
+                    String date;
+                    try {
+                        date = convertDateColumn(rows[1]);
+                    } catch (IllegalArgumentException e) {
+                        throw new StateFileFormatException(path, lineNum);
+                    }
+                    if (date.equals(day)) {
+                        try {
+                            double x = Double.parseDouble(rows[2]);  // [km]
+                            double y = Double.parseDouble(rows[3]);  // [km]
+                            double z = Double.parseDouble(rows[4]);  // [km]
+                            double vx = Double.parseDouble(rows[5]);  // [km/s]
+                            double vy = Double.parseDouble(rows[6]);  // [km/s]
+                            double vz = Double.parseDouble(rows[7]);  // [km/s]
+                            b.setState(new Vector3(x * 1000, y * 1000, z * 1000), new Vector3(vx * 1000, vy * 1000, vz * 1000));
+                        } catch (NumberFormatException e) {
+                            throw new StateFileFormatException(path, lineNum);
+                        }
+                        return true;
+                    }
+                }
+
+                state = nextState;
+            }
+        } catch (IOException e) {
+            if (e instanceof FileNotFoundException) {
+                throw new StateFileNotFoundException(path);
+            } else {
+                throw e;
+            }
+        }
         return false;
     }
+
+    private static String convertDateColumn(String column) {
+        Matcher m = DATE_COLUMN_FORMAT.matcher(column);
+        if (!m.matches()) {
+            throw new IllegalArgumentException();
         }
 
+        return m.group("year") + "-" + convertMonth(m.group("month")) + "-" + m.group("day");
+    }
+
+    public static String convertDate(String date) {
+        Matcher m = DATE_FORMAT_YYYY_MMM_DD.matcher(date);
+        if (!m.matches()) {
+            throw new IllegalArgumentException();
+        }
+        return m.group("year") + "-" + convertMonth(m.group("month")) + "-" + m.group("day");
+    }
+
+    private static String convertMonth(String month) {
+        return switch (month) {
+            case "Jan" -> "01";
+            case "Feb" -> "02";
+            case "Mar" -> "03";
+            case "Apr" -> "04";
+            case "May" -> "05";
+            case "Jun" -> "06";
+            case "Jul" -> "07";
+            case "Aug" -> "08";
+            case "Sep" -> "09";
+            case "Oct" -> "10";
+            case "Nov" -> "11";
+            case "Dec" -> "12";
+            default -> throw new IllegalArgumentException();
+        };
+    }
+
+    private enum State {
+        Pre, In, Post;
+
+        public State next(String line) {
+            switch (this) {
+                case Pre: if (line.equals("$$SOE")) return In; break;
+                case In: if (line.equals("$$EOE")) return Post; break;
+                case Post: break;
+            }
+            return this;
+        }
+    }
+}

src/Simulation8.java

@@ -1,7 +1,11 @@
 import codedraw.CodeDraw;
 
-// Simulates the solar system.
-//
+import java.awt.*;
+import java.io.IOException;
+
+/**
+ * Simulates the solar system.
+ */
 public class Simulation8 {
 
     // gravitational constant
@@ -17,44 +21,100 @@ public class Simulation8 {
 
     // The main simulation method using instances of other classes.
     public static void main(String[] args) {
+        if (args.length != 2) {
+            System.err.println("Error: wrong number of arguments.");
+            System.exit(1);
+        }
+
+        String statePath = args[0];
+        String date;
+        try {
+            date = ReadDataUtil.convertDate(args[1]);
+        } catch (IllegalArgumentException e) {
+            System.err.println("Error: State has wrong format (requires YYYY-MMM-DD), aborting.");
+            System.exit(2);
+            return;
+        }
 
         // simulation
         CodeDraw cd = new CodeDraw();
 
         // create solar system with 13 bodies
-        MassiveForceTreeMap map = new MassiveForceTreeMap();
+        MassiveForceTreeMap forceOnBody = new MassiveForceTreeMap();
 
-        map.put(new NamedBody("Oumuamua", 8e6, new Vector3(0, 0, 0), new Vector3(0, 0, 0)),
-                new Vector3(0, 0, 0));
-        map.put(new NamedBody("Earth", 5.972E24, new Vector3(0, 0, 0), new Vector3(0, 0, 0)),
-                new Vector3(0, 0, 0));
-        map.put(new NamedBody("Moon", 7.349E22, new Vector3(0, 0, 0), new Vector3(0, 0, 0)),
-                new Vector3(0, 0, 0));
-        map.put(new NamedBody("Mars1", 6.41712E23, new Vector3(0, 0, 0), new Vector3(0, 0, 0)),
-                new Vector3(0, 0, 0));
-        map.put(new NamedBody("Deimos", 1.8E20, new Vector3(0, 0, 0), new Vector3(0, 0, 0)),
-                new Vector3(0, 0, 0));
-        map.put(new NamedBody("Phobos", 1.08E20, new Vector3(0, 0, 0), new Vector3(0, 0, 0)),
-                new Vector3(0, 0, 0));
-        map.put(new NamedBody("Mercury", 3.301E23, new Vector3(0, 0, 0), new Vector3(0, 0, 0)),
-                new Vector3(0, 0, 0));
-        map.put(new NamedBody("Venus", 4.86747E24, new Vector3(0, 0, 0), new Vector3(0, 0, 0)),
-                new Vector3(0, 0, 0));
-        map.put(new NamedBody("Vesta", 2.5908E20, new Vector3(0, 0, 0), new Vector3(0, 0, 0)),
-                new Vector3(0, 0, 0));
-        map.put(new NamedBody("Pallas", 2.14E20, new Vector3(0, 0, 0), new Vector3(0, 0, 0)),
-                new Vector3(0, 0, 0));
-        map.put(new NamedBody("Hygiea", 8.32E19, new Vector3(0, 0, 0), new Vector3(0, 0, 0)),
-                new Vector3(0, 0, 0));
-        map.put(new NamedBody("Ceres1", 9.394E20, new Vector3(0, 0, 0), new Vector3(0, 0, 0)),
-                new Vector3(0, 0, 0));
+        forceOnBody.put(new NamedBody("Oumuamua", 8e6), new Vector3());
+        forceOnBody.put(new NamedBody("Earth", 5.972E24), new Vector3());
+        forceOnBody.put(new NamedBody("Moon", 7.349E22), new Vector3());
+        forceOnBody.put(new NamedBody("Mars", 6.41712E23), new Vector3());
+        forceOnBody.put(new NamedBody("Deimos", 1.8E20), new Vector3());
+        forceOnBody.put(new NamedBody("Phobos", 1.08E20), new Vector3());
+        forceOnBody.put(new NamedBody("Mercury", 3.301E23), new Vector3());
+        forceOnBody.put(new NamedBody("Venus", 4.86747E24), new Vector3());
+        forceOnBody.put(new NamedBody("Vesta", 2.5908E20), new Vector3());
+        forceOnBody.put(new NamedBody("Pallas", 2.14E20), new Vector3());
+        forceOnBody.put(new NamedBody("Hygiea", 8.32E19), new Vector3());
+        forceOnBody.put(new NamedBody("Ceres", 9.394E20), new Vector3());
 
+        MassiveIterator iter = forceOnBody.getKeys().iterator();
+        while (iter.hasNext()) {
+            Massive a = iter.next();
+            if (a instanceof NamedBody b) {
+                boolean remove = false;
 
-        //TODO: implementation of this method according to 'Aufgabenblatt8.md'.
+                try {
+                    boolean found = ReadDataUtil.readConfiguration(b, statePath + "/" + b.getName() + ".txt", date);
+                    if (!found) {
+                        System.err.println("Warning: State not available for " + b.getName() + ".");
+                        remove = true;
+                    }
+                } catch (IOException e) {
+                    if (e instanceof StateFileNotFoundException notFound) {
+                        System.err.println("Warning: " + notFound.getMessage());
+                    } else if (e instanceof StateFileFormatException format) {
+                        System.err.println("Warning: " + format.getMessage());
+                    } else {
+                        System.err.println("Error: " + e.getMessage());
+                        System.exit(3);
+                    }
+                    remove = true;
+                }
+
+                if (remove) {
+                    System.err.println("Running simulation without " + b.getName());
+                    iter.remove();
+                }
+            }
+        }
 
         // add sun after states have been read from files.
-        map.put(new NamedBody("Sun", 1.989E30, new Vector3(0, 0, 0), new Vector3(0, 0, 0)),
-                new Vector3(0, 0, 0));
+        forceOnBody.put(new NamedBody("Sun", 1.989E30), new Vector3());
 
+        System.out.println("Starting simulation");
+        long seconds = 0;
+        while (true) {
+            seconds++;
+
+            for (Massive b1 : forceOnBody.getKeys()) {
+                Vector3 force = new Vector3();
+                for (Massive b2 : forceOnBody.getKeys()) {
+                    if (b1 != b2) {
+                        force = force.plus(b1.gravitationalForce(b2));
+                    }
+                }
+                forceOnBody.put(b1, force);
+            }
+
+            for (Massive body : forceOnBody.getKeys()) {
+                body.move(forceOnBody.get(body));
+            }
+
+            if ((seconds % 3600) == 0) {
+                cd.clear(Color.BLACK);
+                for (Massive body : forceOnBody.getKeys()) {
+                    body.draw(cd);
+                }
+                cd.show();
+            }
+        }
     }
 }

src/Simulation9.java

@@ -1,7 +1,122 @@
-// Simulates the solar system.
-//
+import codedraw.CodeDraw;
+
+import java.awt.*;
+import java.io.IOException;
+import java.util.HashMap;
+import java.util.Iterator;
+
+/**
+ * Simulates the solar system.
+ */
 public class Simulation9 {
 
-    // TODO: Implement the simulation using the Java-Collections framework.
+    // gravitational constant
+    public static final double G = 6.6743e-11;
 
+    // one astronomical unit (AU) is the average distance of earth to the sun.
+    public static final double AU = 150e9; // meters
+
+    // set some system parameters
+    public static final double SECTION_SIZE = 10 * AU; // the size of the square region in space
+
+    // all quantities are based on units of kilogram respectively second and meter.
+
+    // The main simulation method using instances of other classes.
+    public static void main(String[] args) {
+        if (args.length != 2) {
+            System.err.println("Error: wrong number of arguments.");
+            System.exit(1);
+        }
+
+        String statePath = args[0];
+        String date;
+        try {
+            date = ReadDataUtil.convertDate(args[1]);
+        } catch (IllegalArgumentException e) {
+            System.err.println("Error: State has wrong format (requires YYYY-MMM-DD), aborting.");
+            System.exit(2);
+            return;
+        }
+
+        // simulation
+        CodeDraw cd = new CodeDraw();
+
+        // create solar system with 13 bodies
+        HashMap<Massive, Vector3> forceOnBody = new HashMap<>();
+
+        forceOnBody.put(new NamedBody("Oumuamua", 8e6), new Vector3());
+        forceOnBody.put(new NamedBody("Earth", 5.972E24), new Vector3());
+        forceOnBody.put(new NamedBody("Moon", 7.349E22), new Vector3());
+        forceOnBody.put(new NamedBody("Mars", 6.41712E23), new Vector3());
+        forceOnBody.put(new NamedBody("Deimos", 1.8E20), new Vector3());
+        forceOnBody.put(new NamedBody("Phobos", 1.08E20), new Vector3());
+        forceOnBody.put(new NamedBody("Mercury", 3.301E23), new Vector3());
+        forceOnBody.put(new NamedBody("Venus", 4.86747E24), new Vector3());
+        forceOnBody.put(new NamedBody("Vesta", 2.5908E20), new Vector3());
+        forceOnBody.put(new NamedBody("Pallas", 2.14E20), new Vector3());
+        forceOnBody.put(new NamedBody("Hygiea", 8.32E19), new Vector3());
+        forceOnBody.put(new NamedBody("Ceres", 9.394E20), new Vector3());
+
+        Iterator<Massive> iter = forceOnBody.keySet().iterator();
+        while (iter.hasNext()) {
+            Massive a = iter.next();
+            if (a instanceof NamedBody b) {
+                boolean remove = false;
+
+                try {
+                    boolean found = ReadDataUtil.readConfiguration(b, statePath + "/" + b.getName() + ".txt", date);
+                    if (!found) {
+                        System.err.println("Warning: State not available for " + b.getName() + ".");
+                        remove = true;
+                    }
+                } catch (IOException e) {
+                    if (e instanceof StateFileNotFoundException notFound) {
+                        System.err.println("Warning: " + notFound.getMessage());
+                    } else if (e instanceof StateFileFormatException format) {
+                        System.err.println("Warning: " + format.getMessage());
+                    } else {
+                        System.err.println("Error: " + e.getMessage());
+                        System.exit(3);
+                    }
+                    remove = true;
+                }
+
+                if (remove) {
+                    System.err.println("Running simulation without " + b.getName());
+                    iter.remove();
+                }
+            }
+        }
+
+        // add sun after states have been read from files.
+        forceOnBody.put(new NamedBody("Sun", 1.989E30), new Vector3());
+
+        System.out.println("Starting simulation");
+        long seconds = 0;
+        while (true) {
+            seconds++;
+
+            for (Massive b1 : forceOnBody.keySet()) {
+                Vector3 force = new Vector3();
+                for (Massive b2 : forceOnBody.keySet()) {
+                    if (b1 != b2) {
+                        force = force.plus(b1.gravitationalForce(b2));
+                    }
+                }
+                forceOnBody.put(b1, force);
+            }
+
+            for (Massive body : forceOnBody.keySet()) {
+                body.move(forceOnBody.get(body));
+            }
+
+            if ((seconds % 3600) == 0) {
+                cd.clear(Color.BLACK);
+                for (Massive body : forceOnBody.keySet()) {
+                    body.draw(cd);
+                }
+                cd.show();
+            }
+        }
+    }
 }

src/StateFileFormatException.java

@@ -1,7 +1,20 @@
 import java.io.IOException;
 
 public class StateFileFormatException extends IOException {
+    private final String fileName;
+    private final long lineNum;
 
-    // TODO: implement class
-
+    public StateFileFormatException(String fileName, long lineNum) {
+        super("File " + fileName + " has illegal format (line " + lineNum + ")");
+        this.fileName = fileName;
+        this.lineNum = lineNum;
+    }
+
+    public String getFileName() {
+        return this.fileName;
+    }
+
+    public long getLineNum() {
+        return this.lineNum;
+    }
 }

src/StateFileNotFoundException.java

@@ -1,7 +1,14 @@
 import java.io.IOException;
 
 public class StateFileNotFoundException extends IOException {
+    private final String fileName;
 
-    // TODO: implement class
-
+    public StateFileNotFoundException(String fileName) {
+        super("File " + fileName + " not found.");
+        this.fileName = fileName;
+    }
+
+    public String getFileName() {
+        return this.fileName;
+    }
 }