word count applications

src/WordFrequency.java

@@ -1,5 +1,61 @@
+import java.io.File;
+import java.io.FileNotFoundException;
+import java.util.Map;
+import java.util.Scanner;
+import java.util.TreeMap;
+
 public class WordFrequency {
     public static void main(String[] args) {
-        System.out.println("Hello world!");
+
+        // creates an empty map (empty symbol table)
+        Map<String, String> petTable = new TreeMap<>();
+        // TreeMap keys are in order, HashMap keys are random
+
+        // put a few itesm into map
+        petTable.put("Leo", "Husky");
+        petTable.put("Chester", "Labrador Retriever");
+        petTable.put("Buddy", "Golden Retriever");
+
+        System.out.println(petTable);
+
+        // use get method key to return value. Does not work the other way
+        String find = petTable.get("Leo");
+        System.out.println(find);
+
+        // change the value
+        petTable.put("Leo", "The Golden doodle");
+        System.out.println(petTable.get("Leo"));
+
+        // keys | values
+        // "the" | 12
+        // "city" | 1
+        Map<String, Integer> wordCounts = new TreeMap<>();
+        try {
+            Scanner scan = new Scanner(new File("tale.txt"));
+            while (scan.hasNext()) {
+                String word = scan.next();
+                if(wordCounts.containsKey(word)) {
+                    // increment the count (value)
+                    // get the existing value out then increment
+                    int value = wordCounts.get(word);
+                    value++;
+                    // update and put the updated value
+                    wordCounts.put(word,value);
+                } else {
+                    // add words to the map with a value of 1
+                    wordCounts.put(word,1);
+                }
+            } // end of while
+            System.out.println(wordCounts);
+
+            // write a loop to talk through items in map
+            for (String key : wordCounts.keySet()) {
+                int value = wordCounts.get(key);
+                System.out.println("words " + key + " appears " + value);
+            }
+        }
+        catch(Exception e) {
+            e.printStackTrace();
+        }
     }
 }