Java Reference
In-Depth Information
7
import
java.util.Scanner;
8
9
public class
WordTypeCount
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{
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public static void
main(String[] args)
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{
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// create HashMap to store String keys and Integer values
Map<String, Integer> myMap =
new
HashMap<>();
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15
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createMap(myMap);
// create map based on user input
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displayMap(myMap);
// display map content
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}
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// create map from user input
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private static void
createMap(Map<String, Integer> map)
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{
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Scanner scanner =
new
Scanner(System.in);
// create scanner
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System.out.println(
"Enter a string:"
);
// prompt for user input
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String input = scanner.nextLine();
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// tokenize the input
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String[] tokens = input.split(
" "
);
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// processing input text
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for
(String token : tokens)
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{
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String word = token.toLowerCase();
// get lowercase word
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// if the map contains the word
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if
(
map.containsKey(word)
)
// is word in map
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{
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int
count = map.get(word);
// get current count
map.put(word, count +
1
);
// increment count
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}
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else
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map.put(word,
1
);
// add new word with a count of 1 to map
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}
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}
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// display map content
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private static void
displayMap(Map<String, Integer> map)
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{
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Set<String> keys = map.keySet();
// get keys
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// sort keys
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TreeSet<String> sortedKeys =
new
TreeSet<>(keys);
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System.out.printf(
"%nMap contains:%nKey\t\tValue%n"
);
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// generate output for each key in map
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for
(String key : sortedKeys)
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System.out.printf(
"%-10s%10s%n"
, key,
map.get(key)
);
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Fig. 16.18
|
Program counts the number of occurrences of each word in a
String
. (Part 2 of 3.)
