Java code cleaner than my browser history (Except PathFinder he is incomplete)

src/Encryption/AdvancedEncryption.java

@@ -0,0 +1,68 @@
+package Encryption;
+
+import org.junit.jupiter.api.Assertions;
+import org.junit.jupiter.api.Test;
+
+import javax.crypto.*;
+import javax.crypto.spec.SecretKeySpec;
+import java.nio.charset.StandardCharsets;
+import java.security.*;
+import java.util.Base64;
+
+public class AdvancedEncryption
+{
+
+
+    private static final String CIPHER = "AES";
+
+    private static Key getSecureRandomKey(String cipher, int keySize)
+    {
+        byte[] secureRandomKeyBytes = new byte[keySize / 8];
+        SecureRandom secureRandom = new SecureRandom();
+        secureRandom.nextBytes(secureRandomKeyBytes);
+        return new SecretKeySpec(secureRandomKeyBytes, cipher);
+    }
+
+    public static String encrypt(String algorithm, String input, SecretKey key) throws NoSuchPaddingException, NoSuchAlgorithmException,
+            InvalidKeyException,
+            BadPaddingException, IllegalBlockSizeException
+    {
+
+        Cipher cipher = Cipher.getInstance(algorithm);
+        cipher.init(Cipher.ENCRYPT_MODE, key);
+        byte[] cipherText = cipher.doFinal(input.getBytes(StandardCharsets.UTF_8));
+        return Base64.getEncoder().encodeToString(cipherText);
+    }
+
+    public static String decrypt(String algorithm, String cipherText, SecretKey key) throws NoSuchPaddingException, NoSuchAlgorithmException,
+            InvalidKeyException,
+            BadPaddingException, IllegalBlockSizeException
+    {
+
+        Cipher cipher = Cipher.getInstance(algorithm);
+        cipher.init(Cipher.DECRYPT_MODE, key);
+        byte[] plainText = cipher.doFinal(Base64.getDecoder().decode(cipherText));
+
+        return new String(plainText);
+    }
+
+    @Test
+    void Key_Of_128_Speed()
+            throws NoSuchAlgorithmException, IllegalBlockSizeException, InvalidKeyException,
+            BadPaddingException, InvalidAlgorithmParameterException, NoSuchPaddingException
+    {
+
+        String input = "012345678901234567890012345678912";
+        SecretKey key = (SecretKey) getSecureRandomKey("AES", 128);
+        String algorithm = "AES/ECB/PKCS5Padding";
+        String cipherText = encrypt(algorithm, input , key);
+        long start = System.nanoTime();
+        String plainText = decrypt(algorithm, cipherText, key);
+        long finish = System.nanoTime();
+        Assertions.assertEquals(input, plainText);
+        long time = finish - start;
+        System.out.println(time + " nanoseconds");
+    }
+
+}
+

src/FindPathsPls/FindPathsMatrix.java

@@ -0,0 +1,70 @@
+package FindPathsPls;
+
+import java.util.Arrays;
+
+public class FindPathsMatrix
+{
+  public static void main(String[] args)
+  {
+    int[][] M1 =
+            {
+                    {1, 2, 3, 4},
+                    {3, 4, 5, 6},
+                    {6, 7, 8, 10},
+                    {2, 5, 2, 8}
+            };
+    GetPaths(M1);
+  }
+  public static void GetPaths(int[][] M)
+  {
+    int[][] output = MultiplyMatrix(M,M);
+    assert output != null;
+    for (int[] ints : output) System.out.println(Arrays.toString(ints));
+
+  }
+
+  public static int[][] MultiplyMatrix(int[][] M1, int[][] M2)
+  {
+    if(M1.length == M2[0].length)
+    {
+      int[][] output = new int[M1.length][M1.length];
+      for (int i = 0; i < M1.length; i++)
+      {
+        int[] R = getRow(M1, i);
+        for (int j = 0; j < M2.length; j++)
+        {
+          int[] C = getColumn(M2, j);
+          output[i][j] = RxC(R, C);
+        }
+      }
+      return output;
+    }
+    else
+      return null;
+  }
+
+  public static int[] getColumn(int[][] input , int index)
+  {
+    int[] output = new int[input.length];
+    for(int i = 0; i < input.length; i++)
+      output[i] = input[i][index];
+    return output;
+  }
+
+  public static int[] getRow(int[][] input , int index)
+  {
+    return input[index];
+  }
+
+  public static int RxC(int[] R , int[] C)
+  {
+    int output = 0;
+    int temp;
+    for (int i = 0; i < R.length ; i++)
+    {
+      temp = R[i] * C[i];
+      output += temp;
+    }
+    return output;
+  }
+}

src/FindPathsPls/FindPathsMatrixTest.java

@@ -0,0 +1,49 @@
+package FindPathsPls;
+
+import org.junit.jupiter.api.Test;
+
+import java.util.Arrays;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+class FindPathsMatrixTest
+{
+
+
+    @Test
+    void getColumn()
+    {
+        int[][] M1 =
+            {
+                    {1, 2, 3},
+                    {3, 4, 5},
+                    {6, 7, 8}
+            };
+        assertEquals(Arrays.toString(new int[]{1, 3, 6}), Arrays.toString(FindPathsMatrix.getColumn(M1,0)));
+    }
+
+    @Test
+    void getRow()
+    {
+        int[][] M1 =
+            {
+                    {1, 2, 3},
+                    {3, 4, 5},
+                    {6, 7, 8}
+            };
+
+        assertEquals(Arrays.toString(new int[]{1, 2, 6}), Arrays.toString(FindPathsMatrix.getRow(M1,0)));
+    }
+
+    @Test
+    void rxC()
+    {
+        int[][] M1 =
+            {
+                    {1, 2, 3},
+                    {3, 4, 5},
+                    {6, 7, 8}
+            };
+        assertEquals(25,FindPathsMatrix.RxC(FindPathsMatrix.getRow(M1,0),FindPathsMatrix.getColumn(M1,0)));
+    }
+}

src/FindPathsPls/PathFinder.java

@@ -0,0 +1,124 @@
+package FindPathsPls;
+
+import java.util.ArrayList;
+import java.util.Arrays;
+
+public class PathFinder
+{
+    public static void main(String[] args)
+    {
+        ArrayList<String[]> Graph = new ArrayList<>();
+        Graph.add(new String[]{"", "e1", "e3"});
+        Graph.add( new String[]{"e1", "", "e2"});
+        Graph.add( new String[]{"e3", "e2", ""});
+        GetPaths(Graph,3,3,2);
+        ArrayList<String[]> ExtremeGraph = new ArrayList<>();
+        ArrayList<String[]> Graph2 = new ArrayList<>();
+        Graph2.add(new String[]{"", "e1,e2,e3", "e3,e4"});
+        Graph2.add( new String[]{"e1,e2,e3", "", "e6"});
+        Graph2.add( new String[]{"e3,e4", "e6", ""});
+        GetPaths(Graph2,3,3,2);
+
+    }
+    private static void GetPaths(ArrayList<String[]> Graph , int row_len, int col_len, int path_len)
+    {
+        int power =2;
+        int count = 0;
+        if(path_len == 2)
+        {
+            ArrayList<String[]> output = SquareMatrix(Graph, row_len, col_len);
+            for(int i = 0; i < output.size();i++)
+            {
+                count++;
+                System.out.print(Arrays.toString(output.get(i))+"  ,  ");
+                if(count % 3 == 0)
+                    System.out.println();
+            }
+        }
+        else
+        {
+            ArrayList<String[]> output = Graph;
+
+            while(power <= path_len)
+            {
+                output = MultiplyMatrix(output, Graph, row_len, col_len);
+                power++;
+            }
+            for(int i = 0; i <= output.size();i++)
+            {
+                count++;
+                System.out.print(Arrays.toString(output.get(i)));
+                if((count % 3) == 0)
+                    System.out.println();
+            }
+
+        }
+    }
+
+
+    private static ArrayList<String[]> MultiplyMatrix(ArrayList<String[]> M1, ArrayList<String[]> M2, int row_len, int col_len)
+    {
+        return MatrixMultiplication(M1, M2, row_len, col_len);
+    }
+
+    private static ArrayList<String[]> MatrixMultiplication(ArrayList<String[]> M1, ArrayList<String[]> M2, int row_len, int col_len)
+    {
+        String[] R;
+        String[] C;
+        ArrayList<String[]> output = new ArrayList<>();
+        for(int rows = 0; rows < row_len; rows++)
+        {
+            R = getRow(M1,rows);
+
+            for (int cols = 0; cols < col_len; cols++)
+            {
+                C = getColumn(M2, cols);
+                output.add(findCart(R, C));
+            }
+        }
+        return output;
+    }
+
+
+    private static ArrayList<String[]> SquareMatrix(ArrayList<String[]> input, int row_len, int col_len)
+    {
+        return MatrixMultiplication(input, input, row_len, col_len);
+
+    }
+
+    public static String[] findCart(String[] arr1, String[] arr2)
+    {
+        ArrayList<String> list = new ArrayList<>();
+        for (String s : arr1)
+            for (String value : arr2)
+            {
+                if (!(s.equals("") || value.equals("")))
+                {
+                    list.add(s + "->" + value);
+                }
+
+            }
+        String[] arr = new String[list.size()];
+
+        return list.toArray(arr);
+    }
+
+    public static String[] getColumn(ArrayList<String[]> input , int index)
+    {
+        String[] output = new String[input.size()];
+        for(int i = 0; i < input.size(); i++)
+        {
+            if(input.get(i) != null)
+            output[i] = input.get(i)[index];
+        }
+        return output;
+
+    }
+
+
+    public static String[] getRow(ArrayList<String[]> input , int index)
+    {
+        return input.get(index);
+    }
+
+}

src/Stopwatch/StopWatch.java

@@ -6,7 +6,7 @@ import java.time.temporal.ChronoUnit;
 public class StopWatch
 {
     private LocalTime startTime,endTime;
-    StopWatch()
+    public StopWatch()
     {
         startTime=LocalTime.of(0,0,0);
         endTime= LocalTime.of(0,0,0);

src/Stopwatch/StopWatchTest.java

@@ -16,16 +16,16 @@ public class StopWatchTest
        StopWatch Watch2 = new StopWatch();
        StopWatch Watch3 = new StopWatch();
        StopWatch Watch4 = new StopWatch();
-        Watch1.start();
-        try
-        {
-            TimeUnit.MINUTES.sleep(1);
-        }
-        catch (InterruptedException e)
-        {
-            e.printStackTrace();
-        }
-        Watch1.stop();
+//        Watch1.start();
+//        try
+//        {
+//            TimeUnit.MINUTES.sleep(1);
+//        }
+//        catch (InterruptedException e)
+//        {
+//            e.printStackTrace();
+//        }
+//        Watch1.stop();
 
         Watch2.start();
         TimeUnit.MILLISECONDS.sleep(69);
@@ -43,7 +43,7 @@ public class StopWatchTest
 
 
 
-        assertEquals(60000, Watch1.getElapsedTime(), 10);
+//        assertEquals(60000, Watch1.getElapsedTime(), 10);
         assertEquals(69, Watch2.getElapsedTime(),10);
         assertEquals(10, Watch3.getElapsedTime(),10);
         assertEquals(69, Watch4.getElapsedTime(),10);