Change project structure to a Maven Java project + Refactor (#2816)

src/main/java/com/thealgorithms/conversions/HexaDecimalToBinary.java

@@ -0,0 +1,34 @@
+package com.thealgorithms.conversions;
+
+// Hex [0-9],[A-F] -> Binary [0,1]
+public class HexaDecimalToBinary {
+
+    private final int LONG_BITS = 8;
+
+    public void convert(String numHex) {
+        // String a HexaDecimal:
+        int conHex = Integer.parseInt(numHex, 16);
+        // Hex a Binary:
+        String binary = Integer.toBinaryString(conHex);
+        // Output:
+        System.out.println(numHex + " = " + completeDigits(binary));
+    }
+
+    public String completeDigits(String binNum) {
+        for (int i = binNum.length(); i < LONG_BITS; i++) {
+            binNum = "0" + binNum;
+        }
+        return binNum;
+    }
+
+    public static void main(String[] args) {
+
+        // Testing Numbers:
+        String[] hexNums = {"1", "A1", "ef", "BA", "AA", "BB", "19", "01", "02", "03", "04"};
+        HexaDecimalToBinary objConvert = new HexaDecimalToBinary();
+
+        for (String num : hexNums) {
+            objConvert.convert(num);
+        }
+    }
+}