Question

given a input file, parse it and answer the following frequency related questions, using java.

-list the most frequent word(s) in the whole file and its frequency.

-list sentence(s) with the max. number of occurrences of the word “of” in the entire file and also list the corresponding frequency.

program has two arguments;

1st : path to the input text file

2nd : name prefix for the output files

ex.

$ java assgn1 “./input.txt” “output”

outputs: for each question create one single output file. so program should produce 2 output files each time it runs

Answer 1

/////////////////////////////

// compile and run

// javac assign1.java input.txt output

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import java.io.*;
import java.io.BufferedReader;
import java.io.DataInputStream;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.ArrayList;
import java.util.Collections;
import java.util.Comparator;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.Set;
import java.util.StringTokenizer;
import java.util.Map.Entry;

public class assign1 {
public Map<String, Integer> getWordCount(String fileName){
FileInputStream fis = null;
DataInputStream dis = null;
BufferedReader br = null;
Map<String, Integer> wordMap = new HashMap<String, Integer>();
try {
fis = new FileInputStream(fileName);
dis = new DataInputStream(fis);
br = new BufferedReader(new InputStreamReader(dis));
String line = null;
while((line = br.readLine()) != null){
StringTokenizer st = new StringTokenizer(line, " ");
while(st.hasMoreTokens()){
String tmp = st.nextToken().toLowerCase();
if(wordMap.containsKey(tmp)){
wordMap.put(tmp, wordMap.get(tmp)+1);
} else {
wordMap.put(tmp, 1);
}
}
}
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
} finally{
try{if(br != null) br.close();}catch(Exception ex){}
}
return wordMap;
}

public List<Entry<String, Integer>> sortByValue(Map<String, Integer> wordMap){
Set<Entry<String, Integer>> set = wordMap.entrySet();
List<Entry<String, Integer>> list = new ArrayList<Entry<String, Integer>>(set);
Collections.sort( list, new Comparator<Map.Entry<String, Integer>>()
{
public int compare( Map.Entry<String, Integer> o1, Map.Entry<String, Integer> o2 )
{
return (o2.getValue()).compareTo( o1.getValue() );
}
} );
return list;
}

public static void main(String a[]) throws FileNotFoundException{

   assign1 mdc = new assign1();
Map<String, Integer> wordMap = mdc.getWordCount(a[0]);
List<Entry<String, Integer>> list = mdc.sortByValue(wordMap);

   PrintStream o = new PrintStream(new File(a[1]+".txt"));
   System.setOut(o);
   for(Map.Entry<String, Integer> entry:list){
System.out.println(entry.getKey()+" :\t "+entry.getValue());
}
}
}