week 2 challenge

fall23/Week13/SNAFU.java

@@ -0,0 +1,85 @@
+package fall23.Week13;
+
+import java.io.BufferedReader;
+import java.io.FileNotFoundException;
+import java.io.FileReader;
+import java.io.IOException;
+import java.util.Iterator;
+
+/**
+ * Provides code for the input and testing of the SNAFU Challenge. This
+ * challenge and input is from Day 25, year 2022 from AdventOfCode.com.
+ */
+public class SNAFU {
+	/**
+	 * 
+	 * @return returns an Iterable form of the input.
+	 */
+	public static Iterable<String> iterableInput() {
+		return new Input();
+	}
+
+	/**
+	 * Classes that implement Iterable tell Java that the class can be trusted to
+	 * have an Iterator. A very common and nice use is in for loops. See, Arrays and
+	 * a number of other datastructures implement Iterable, and you can stick any
+	 * Iterable class in the for-each loop.
+	 */
+	private static class Input implements Iterable<String> {
+		/**
+		 * This is the only method required by Iterable.
+		 */
+		@Override
+		public Iterator<String> iterator() {
+			return new SNAFUIterator();
+		}
+
+		/**
+		 * This is the manual version of the for each loop. There are two methods
+		 * inside. Next() gives the next input (and iterates). HasNext() is called
+		 * before to check if Next() can be safely run. The for loop basically keeps
+		 * calling Next() while HasNext() is true. Next() is actually the input given to
+		 * the left half of the for each loop.
+		 * 
+		 * In this case, this Iterator keeps going until the next line it has ready is
+		 * null.
+		 */
+		private class SNAFUIterator implements Iterator<String> {
+			private final static String PATH = "Input.txt";
+
+			private BufferedReader reader;
+			private String currLine;
+
+			private SNAFUIterator() {
+				try {
+					reader = new BufferedReader(new FileReader(PATH));
+					iterateToNextLine();
+				} catch (FileNotFoundException e) {
+					System.out.println("File Not Found");
+					e.printStackTrace();
+				}
+			}
+
+			private void iterateToNextLine() {
+				try {
+					currLine = reader.readLine();
+				} catch (IOException e) {
+					System.out.println("Error With Reader");
+					e.printStackTrace();
+				}
+			}
+
+			@Override
+			public boolean hasNext() {
+				return (currLine != null);
+			}
+
+			@Override
+			public String next() {
+				String returnStr = currLine;
+				iterateToNextLine();
+				return returnStr;
+			}
+		}
+	}
+}