diff --git a/src/test/java/com/mattrixwv/CipherStreamJava/monoSubstitution/TestAffine.java b/src/test/java/com/mattrixwv/CipherStreamJava/monoSubstitution/TestAffine.java
new file mode 100644
index 0000000..4d02f81
--- /dev/null
+++ b/src/test/java/com/mattrixwv/CipherStreamJava/monoSubstitution/TestAffine.java
@@ -0,0 +1,449 @@
+//CipherStreamJava/src/test/java/com/mattrixwv/CipherStreamJava/polySubstitution/TestAffine.java
+//Mattrixwv
+// Created: 01-26-22
+//Modified: 01-26-22
+package com.mattrixwv.CipherStreamJava.monoSubstitution;
+
+
+import static org.junit.Assert.assertEquals;
+
+import com.mattrixwv.CipherStreamJava.exceptions.InvalidInputException;
+import com.mattrixwv.CipherStreamJava.exceptions.InvalidKeywordException;
+
+import org.junit.Test;
+
+
+public class TestAffine{
+	@Test
+	public void testEncode() throws InvalidKeywordException, InvalidInputException{
+		Affine cipher = new Affine(true, true, true);
+
+		//Test lowercase encoding
+		String inputString = "messagetoencode";
+		int key1 = 5;
+		int key2 = 7;
+		String correctOutput = "pbtthlbyzburzwb";
+		String output = cipher.encode(key1, key2, inputString);
+		assertEquals("Affine failed lowercase encoding.", correctOutput, output);
+		//Test uppercase encoding
+		inputString = "MESSAGETOENCODE";
+		key1 = 5;
+		key2 = 7;
+		correctOutput = "PBTTHLBYZBURZWB";
+		output = cipher.encode(key1, key2, inputString);
+		assertEquals("Affine failed uppercase encoding.", correctOutput, output);
+
+		//Test whitespace encoding
+		inputString = "message to encode";
+		key1 = 5;
+		key2 = 7;
+		correctOutput = "pbtthlb yz burzwb";
+		output = cipher.encode(key1, key2, inputString);
+		assertEquals("Affine failed whitespace encoding.", correctOutput, output);
+
+		//Test symbol encoding
+		inputString = "message*to+encode-";
+		key1 = 5;
+		key2 = 7;
+		correctOutput = "pbtthlb*yz+burzwb-";
+		output = cipher.encode(key1, key2, inputString);
+		assertEquals("Affine failed symbol encoding.", correctOutput, output);
+
+		//Test mixed case, whitespace, symbol encoding
+		inputString = "Message to^encode";
+		key1 = 5;
+		key2 = 7;
+		correctOutput = "Pbtthlb yz^burzwb";
+		output = cipher.encode(key1, key2, inputString);
+		assertEquals("Affine failed mixed case, whitespace, and symbol encoding.", correctOutput, output);
+	}
+	@Test
+	public void testNoCapitalEncode() throws InvalidKeywordException, InvalidInputException{
+		Affine cipher = new Affine(false, true, true);
+
+		//Test lowercase encoding
+		String inputString = "messagetoencode";
+		int key1 = 5;
+		int key2 = 7;
+		String correctOutput = "pbtthlbyzburzwb";
+		String output = cipher.encode(key1, key2, inputString);
+		assertEquals("Affine failed no capital lowercase encoding.", correctOutput, output);
+		//Test uppercase encoding
+		inputString = "MESSAGETOENCODE";
+		key1 = 5;
+		key2 = 7;
+		correctOutput = "pbtthlbyzburzwb";
+		output = cipher.encode(key1, key2, inputString);
+		assertEquals("Affine failed no capital uppercase encoding.", correctOutput, output);
+
+		//Test whitespace encoding
+		inputString = "message to encode";
+		key1 = 5;
+		key2 = 7;
+		correctOutput = "pbtthlb yz burzwb";
+		output = cipher.encode(key1, key2, inputString);
+		assertEquals("Affine failed no capital whitespace encoding.", correctOutput, output);
+
+		//Test symbol encoding
+		inputString = "message*to+encode-";
+		key1 = 5;
+		key2 = 7;
+		correctOutput = "pbtthlb*yz+burzwb-";
+		output = cipher.encode(key1, key2, inputString);
+		assertEquals("Affine failed no capital symbol encoding.", correctOutput, output);
+
+		//Test mixed case, whitespace, symbol encoding
+		inputString = "Message to^encode";
+		key1 = 5;
+		key2 = 7;
+		correctOutput = "pbtthlb yz^burzwb";
+		output = cipher.encode(key1, key2, inputString);
+		assertEquals("Affine failed no capital mixed case, whitespace, and symbol encoding.", correctOutput, output);
+	}
+	@Test
+	public void testNoWhitespaceEncode() throws InvalidKeywordException, InvalidInputException{
+		Affine cipher = new Affine(true, false, true);
+
+		//Test lowercase encoding
+		String inputString = "messagetoencode";
+		int key1 = 5;
+		int key2 = 7;
+		String correctOutput = "pbtthlbyzburzwb";
+		String output = cipher.encode(key1, key2, inputString);
+		assertEquals("Affine failed no whitespace lowercase encoding.", correctOutput, output);
+		//Test uppercase encoding
+		inputString = "MESSAGETOENCODE";
+		key1 = 5;
+		key2 = 7;
+		correctOutput = "PBTTHLBYZBURZWB";
+		output = cipher.encode(key1, key2, inputString);
+		assertEquals("Affine failed no whitespace uppercase encoding.", correctOutput, output);
+
+		//Test whitespace encoding
+		inputString = "message to encode";
+		key1 = 5;
+		key2 = 7;
+		correctOutput = "pbtthlbyzburzwb";
+		output = cipher.encode(key1, key2, inputString);
+		assertEquals("Affine failed no whitespace whitespace encoding.", correctOutput, output);
+
+		//Test symbol encoding
+		inputString = "message*to+encode-";
+		key1 = 5;
+		key2 = 7;
+		correctOutput = "pbtthlb*yz+burzwb-";
+		output = cipher.encode(key1, key2, inputString);
+		assertEquals("Affine failed no whitespace symbol encoding.", correctOutput, output);
+
+		//Test mixed case, whitespace, symbol encoding
+		inputString = "Message to^encode";
+		key1 = 5;
+		key2 = 7;
+		correctOutput = "Pbtthlbyz^burzwb";
+		output = cipher.encode(key1, key2, inputString);
+		assertEquals("Affine failed no whitespace mixed case, whitespace, and symbol encoding.", correctOutput, output);
+	}
+	@Test
+	public void testNoSymbolEncode() throws InvalidKeywordException, InvalidInputException{
+		Affine cipher = new Affine(true, true, false);
+
+		//Test lowercase encoding
+		String inputString = "messagetoencode";
+		int key1 = 5;
+		int key2 = 7;
+		String correctOutput = "pbtthlbyzburzwb";
+		String output = cipher.encode(key1, key2, inputString);
+		assertEquals("Affine failed no symbol lowercase encoding.", correctOutput, output);
+		//Test uppercase encoding
+		inputString = "MESSAGETOENCODE";
+		key1 = 5;
+		key2 = 7;
+		correctOutput = "PBTTHLBYZBURZWB";
+		output = cipher.encode(key1, key2, inputString);
+		assertEquals("Affine failed no symbol uppercase encoding.", correctOutput, output);
+
+		//Test whitespace encoding
+		inputString = "message to encode";
+		key1 = 5;
+		key2 = 7;
+		correctOutput = "pbtthlb yz burzwb";
+		output = cipher.encode(key1, key2, inputString);
+		assertEquals("Affine failed no symbol whitespace encoding.", correctOutput, output);
+
+		//Test symbol encoding
+		inputString = "message*to+encode-";
+		key1 = 5;
+		key2 = 7;
+		correctOutput = "pbtthlbyzburzwb";
+		output = cipher.encode(key1, key2, inputString);
+		assertEquals("Affine failed no symbol symbol encoding.", correctOutput, output);
+
+		//Test mixed case, whitespace, symbol encoding
+		inputString = "Message to^encode";
+		key1 = 5;
+		key2 = 7;
+		correctOutput = "Pbtthlb yzburzwb";
+		output = cipher.encode(key1, key2, inputString);
+		assertEquals("Affine failed no symbol mixed case, whitespace, and symbol encoding.", correctOutput, output);
+	}
+	@Test
+	public void testNoCapitalWhitespaceSymbolEncode() throws InvalidKeywordException, InvalidInputException{
+		Affine cipher = new Affine(false, false, false);
+
+		//Test lowercase encoding
+		String inputString = "messagetoencode";
+		int key1 = 5;
+		int key2 = 7;
+		String correctOutput = "pbtthlbyzburzwb";
+		String output = cipher.encode(key1, key2, inputString);
+		assertEquals("Affine failed secure lowercase encoding.", correctOutput, output);
+		//Test uppercase encoding
+		inputString = "MESSAGETOENCODE";
+		key1 = 5;
+		key2 = 7;
+		correctOutput = "pbtthlbyzburzwb";
+		output = cipher.encode(key1, key2, inputString);
+		assertEquals("Affine failed secure uppercase encoding.", correctOutput, output);
+
+		//Test whitespace encoding
+		inputString = "message to encode";
+		key1 = 5;
+		key2 = 7;
+		correctOutput = "pbtthlbyzburzwb";
+		output = cipher.encode(key1, key2, inputString);
+		assertEquals("Affine failed secure whitespace encoding.", correctOutput, output);
+
+		//Test symbol encoding
+		inputString = "message*to+encode-";
+		key1 = 5;
+		key2 = 7;
+		correctOutput = "pbtthlbyzburzwb";
+		output = cipher.encode(key1, key2, inputString);
+		assertEquals("Affine failed secure symbol encoding.", correctOutput, output);
+
+		//Test mixed case, whitespace, symbol encoding
+		inputString = "Message to^encode";
+		key1 = 5;
+		key2 = 7;
+		correctOutput = "pbtthlbyzburzwb";
+		output = cipher.encode(key1, key2, inputString);
+		assertEquals("Affine failed secure mixed case, whitespace, and symbol encoding.", correctOutput, output);
+	}
+
+
+	@Test
+	public void testDecode() throws InvalidKeywordException, InvalidInputException{
+		Affine cipher = new Affine(true, true, true);
+
+		//Test lowercase decoding
+		String inputString = "pbtthlbyzburzwb";
+		int key1 = 5;
+		int key2 = 7;
+		String correctOutput = "messagetoencode";
+		String output = cipher.decode(key1, key2, inputString);
+		assertEquals("Affine failed lowercase decoding.", correctOutput, output);
+		//Test uppsercase decoding
+		inputString = "PBTTHLBYZBURZWB";
+		key1 = 5;
+		key2 = 7;
+		correctOutput = "MESSAGETOENCODE";
+		output = cipher.decode(key1, key2, inputString);
+		assertEquals("Affine failed uppercase decoding.", correctOutput, output);
+
+		//Test whitespace decoding
+		inputString = "pbtthlb yz burzwb";
+		key1 = 5;
+		key2 = 7;
+		correctOutput = "message to encode";
+		output = cipher.decode(key1, key2, inputString);
+		assertEquals("Affine failed whitespace decoding.", correctOutput, output);
+
+		//Test symbol decoding
+		inputString = "pbtthlb*yz+burzwb-";
+		key1 = 5;
+		key2 = 7;
+		correctOutput = "message*to+encode-";
+		output = cipher.decode(key1, key2, inputString);
+		assertEquals("Affine failed symbol decoding.", correctOutput, output);
+
+		//Test mixed case, whitespace, symbol decoding
+		inputString = "Pbtthlb yz^burzwb";
+		key1 = 5;
+		key2 = 7;
+		correctOutput = "Message to^encode";
+		output = cipher.decode(key1, key2, inputString);
+		assertEquals("Affine failed mixed case, whitespace, and symbol decoding.", correctOutput, output);
+	}
+	@Test
+	public void testNoCapitalDecode() throws InvalidKeywordException, InvalidInputException{
+		Affine cipher = new Affine(false, true, true);
+
+		//Test lowercase decoding
+		String inputString = "pbtthlbyzburzwb";
+		int key1 = 5;
+		int key2 = 7;
+		String correctOutput = "messagetoencode";
+		String output = cipher.decode(key1, key2, inputString);
+		assertEquals("Affine failed no capital lowercase decoding.", correctOutput, output);
+		//Test uppsercase decoding
+		inputString = "PBTTHLBYZBURZWB";
+		key1 = 5;
+		key2 = 7;
+		correctOutput = "messagetoencode";
+		output = cipher.decode(key1, key2, inputString);
+		assertEquals("Affine failed no capital uppercase decoding.", correctOutput, output);
+
+		//Test whitespace decoding
+		inputString = "pbtthlb yz burzwb";
+		key1 = 5;
+		key2 = 7;
+		correctOutput = "message to encode";
+		output = cipher.decode(key1, key2, inputString);
+		assertEquals("Affine failed no capital whitespace decoding.", correctOutput, output);
+
+		//Test symbol decoding
+		inputString = "pbtthlb*yz+burzwb-";
+		key1 = 5;
+		key2 = 7;
+		correctOutput = "message*to+encode-";
+		output = cipher.decode(key1, key2, inputString);
+		assertEquals("Affine failed no capital symbol decoding.", correctOutput, output);
+
+		//Test mixed case, whitespace, symbol decoding
+		inputString = "Pbtthlb yz^burzwb";
+		key1 = 5;
+		key2 = 7;
+		correctOutput = "message to^encode";
+		output = cipher.decode(key1, key2, inputString);
+		assertEquals("Affine failed no capital mixed case, whitespace, and symbol decoding.", correctOutput, output);
+	}
+	@Test
+	public void testNoWhitespaceDecode() throws InvalidKeywordException, InvalidInputException{
+		Affine cipher = new Affine(true, false, true);
+
+		//Test lowercase decoding
+		String inputString = "pbtthlbyzburzwb";
+		int key1 = 5;
+		int key2 = 7;
+		String correctOutput = "messagetoencode";
+		String output = cipher.decode(key1, key2, inputString);
+		assertEquals("Affine failed no whitespace lowercase decoding.", correctOutput, output);
+		//Test uppsercase decoding
+		inputString = "PBTTHLBYZBURZWB";
+		key1 = 5;
+		key2 = 7;
+		correctOutput = "MESSAGETOENCODE";
+		output = cipher.decode(key1, key2, inputString);
+		assertEquals("Affine failed no whitespace uppercase decoding.", correctOutput, output);
+
+		//Test whitespace decoding
+		inputString = "pbtthlb yz burzwb";
+		key1 = 5;
+		key2 = 7;
+		correctOutput = "messagetoencode";
+		output = cipher.decode(key1, key2, inputString);
+		assertEquals("Affine failed no whitespace whitespace decoding.", correctOutput, output);
+
+		//Test symbol decoding
+		inputString = "pbtthlb*yz+burzwb-";
+		key1 = 5;
+		key2 = 7;
+		correctOutput = "message*to+encode-";
+		output = cipher.decode(key1, key2, inputString);
+		assertEquals("Affine failed no whitespace symbol decoding.", correctOutput, output);
+
+		//Test mixed case, whitespace, symbol decoding
+		inputString = "Pbtthlb yz^burzwb";
+		key1 = 5;
+		key2 = 7;
+		correctOutput = "Messageto^encode";
+		output = cipher.decode(key1, key2, inputString);
+		assertEquals("Affine failed no whitespace mixed case, whitespace, and symbol decoding.", correctOutput, output);
+	}
+	@Test
+	public void testNoSymbolDecode() throws InvalidKeywordException, InvalidInputException{
+		Affine cipher = new Affine(true, true, false);
+
+		//Test lowercase decoding
+		String inputString = "pbtthlbyzburzwb";
+		int key1 = 5;
+		int key2 = 7;
+		String correctOutput = "messagetoencode";
+		String output = cipher.decode(key1, key2, inputString);
+		assertEquals("Affine failed no symbol lowercase decoding.", correctOutput, output);
+		//Test uppsercase decoding
+		inputString = "PBTTHLBYZBURZWB";
+		key1 = 5;
+		key2 = 7;
+		correctOutput = "MESSAGETOENCODE";
+		output = cipher.decode(key1, key2, inputString);
+		assertEquals("Affine failed no symbol uppercase decoding.", correctOutput, output);
+
+		//Test whitespace decoding
+		inputString = "pbtthlb yz burzwb";
+		key1 = 5;
+		key2 = 7;
+		correctOutput = "message to encode";
+		output = cipher.decode(key1, key2, inputString);
+		assertEquals("Affine failed no symbol whitespace decoding.", correctOutput, output);
+
+		//Test symbol decoding
+		inputString = "pbtthlb*yz+burzwb-";
+		key1 = 5;
+		key2 = 7;
+		correctOutput = "messagetoencode";
+		output = cipher.decode(key1, key2, inputString);
+		assertEquals("Affine failed no symbol symbol decoding.", correctOutput, output);
+
+		//Test mixed case, whitespace, symbol decoding
+		inputString = "Pbtthlb yz^burzwb";
+		key1 = 5;
+		key2 = 7;
+		correctOutput = "Message toencode";
+		output = cipher.decode(key1, key2, inputString);
+		assertEquals("Affine failed no symbol mixed case, whitespace, and symbol decoding.", correctOutput, output);
+	}
+	@Test
+	public void testNoCapitalWhitespaceSymbolDecode() throws InvalidKeywordException, InvalidInputException{
+		Affine cipher = new Affine(false, false, false);
+
+		//Test lowercase decoding
+		String inputString = "pbtthlbyzburzwb";
+		int key1 = 5;
+		int key2 = 7;
+		String correctOutput = "messagetoencode";
+		String output = cipher.decode(key1, key2, inputString);
+		assertEquals("Affine failed secure lowercase decoding.", correctOutput, output);
+		//Test uppsercase decoding
+		inputString = "PBTTHLBYZBURZWB";
+		key1 = 5;
+		key2 = 7;
+		correctOutput = "messagetoencode";
+		output = cipher.decode(key1, key2, inputString);
+		assertEquals("Affine failed secure uppercase decoding.", correctOutput, output);
+
+		//Test whitespace decoding
+		inputString = "pbtthlb yz burzwb";
+		key1 = 5;
+		key2 = 7;
+		correctOutput = "messagetoencode";
+		output = cipher.decode(key1, key2, inputString);
+		assertEquals("Affine failed secure whitespace decoding.", correctOutput, output);
+
+		//Test symbol decoding
+		inputString = "pbtthlb*yz+burzwb-";
+		key1 = 5;
+		key2 = 7;
+		correctOutput = "messagetoencode";
+		output = cipher.decode(key1, key2, inputString);
+		assertEquals("Affine failed secure symbol decoding.", correctOutput, output);
+
+		//Test mixed case, whitespace, symbol decoding
+		inputString = "Pbtthlb yz^burzwb";
+		key1 = 5;
+		key2 = 7;
+		correctOutput = "messagetoencode";
+		output = cipher.decode(key1, key2, inputString);
+		assertEquals("Affine failed secure mixed case, whitespace, and symbol decoding.", correctOutput, output);
+	}
+}