Added Practice Demo Code3.

Signed-off-by: Someshdiwan <Someshdiwan369@gmail.com>

Author: Someshdiwan

Section23JavaIOStreams/DemoCodes/src/Demo3.java

@@ -0,0 +1,21 @@
+import java.io.IOException;
+class Demo3 {
+    public static void main(String[] args)
+    {
+        try
+        {
+            int x = System.in.read();
+            System.out.println( (char)x);
+        }
+        catch (IOException e)
+        {
+            System.out.println(e);
+        }
+    }
+}
+/*
+This program reads one character from the keyboard input (System.in.read()) and prints it.
+It captures any input/output exceptions that might occur during reading.
+
+Basically, it waits for you to press a key and then shows that character.
+*/