/**

* Inserts a document into the search engine for later analysis and retrieval.

*

* The document is uniquely identified by a documentId; attempts to re-insert the same

* document are ignored.

*

* The document is supplied as a Reader; this method stores the document contents for

* later analysis and retrieval.

*

* @param documentId

* @param reader

* @throws IOException iff the reader throws an exception

*/

public void addDocument(DocumentId documentId, Reader reader) throws IOException {

String s = "";

BufferedReader br = new BufferedReader(reader);

while((s = br.readLine()) != null) {

list = Arrays.asList(s.toLowerCase().split("\\W+"));

for(int i = 0; i < list.size(); i++)

{

if(!map.containsKey(list.get(i)))

{

Set newset = new HashSet<>();

newset.add(documentId);

map.put(list.get(i), newset);

}

else

{

Set set = map.get(list.get(i));

set.add(documentId);

map.put(list.get(i), set);

}

}

}

}

/**

* Returns the set of DocumentIds contained within the search engine that contain a given term.

*

* @param term

* @return the set of DocumentIds that contain a given term

*/

public Set indexLookup(String term) {

Set t = new HashSet();

String k = term.toLowerCase();

for(String doc: google.keySet()){

if(doc.contains(k)){

t.add(google.get(doc));

}

}

return t;

}

/**

* Returns the term frequency of a term in a particular document.

*

* The term frequency is number of times the term appears in a document.

*

* See

* @param documentId

* @param term

* @return the term frequency of a term in a particular document

* @throws IllegalArgumentException if the documentId has not been added to the engine

*/

public int termFrequency(DocumentId documentId, String term) throws IllegalArgumentException {

}

/**

* Returns the inverse document frequency of a term across all documents in the index.

*

* For our purposes, IDF is defined as log ((1 + N) / (1 + M)) where

* N is the number of documents in total, and M

* is the number of documents where the term appears.

*

* @param term

* @return the inverse document frequency of term

*/

public double inverseDocumentFrequency(String term) {

}

/**

* Returns a sorted list of documents, most relevant to least relevant, for the given term.

*

* A document with a larger tfidf score is more relevant than a document with a lower tfidf score.

*

* Each document in the returned list must contain the term.

*

* @param term

* @return a list of documents sorted in descending order by tfidf

*/

public List relevanceLookup(String term) {

}

I have this code, and I want to do what the comments above each methods says. I have this declared and imported:

import comparators.TfIdfComparator; import documents.DocumentId;

public Map> map = new HashMap<>();

public List list;

Please help me in the rest of the methods with accordance to the map variable. Also check if iI have the the first (addDocument and indexLookup) implemented correctly.