Class DocumentIndex

java.lang.Object

DocumentIndex

public class DocumentIndex
extends java.lang.Object

The DocumentIndex is used to hold an index created for a document. The class has one field a TreeMap, which has a String key mapped to an IndexEntry value and which holds the index entries created for the document. The key value for the TreeMap is the word that the corresponding IndexEntry holds. The class has one constructor, which only initializes a new TreeMap. It has two main functionalities: addWord and addAllWords. The addWord method takes a String and checks if a String has been used as a key value in the TreeMap yet (essentially if the word has already been added to the index). If the word hasn't been added, a new IndexEntry is created with the word provided and the integer parameter is added as the first line number. Then, the new IndexEntry is added to the TreeMap. If the word has been added, it just adds another number to the TreeSet of line numbers in the IndexEntry already. The addAllWords method splits a String by its spaces, then adds the words in the String to the TreeMap with the number provided. The addAllWords is intended to add a whole line of a document to a DocumentIndex, and uses the addWord method internally. Once again, this class formats the words as uppercase once they have been added to the document. Additionally, I added the methods getKeys() and getEntry(String key) in addition to the required functions because the IndexMaker class needed the ability to access the keys and entries in the index. Both are simple getters that allow access to TreeMap functions that do the same thing.

Author:

AnneMarie Caballero

Field Summary

Fields

Modifier and Type	Field	Description
private java.util.TreeMap<java.lang.String,IndexEntry>	index	A TreeMap with a String key mapped on to an Index Entry value that acts as the index for the document.

Constructor Summary

Constructors

Constructor	Description
DocumentIndex()	Constructs a DocumentIndex by initializing the index field to a default TreeMap

Method Summary

Modifier and Type	Method	Description
void	addAllWords(java.lang.String str, int num)	This method adds all words in a given String to the index.
void	addWord(java.lang.String word, int num)	Adds word to the index by taking the word parameter and checking if it is already in index.
IndexEntry	getEntry(java.lang.String key)	This method returns the corresponding IndexEntry to the key provided if the key set does contain the key.
java.util.Set<java.lang.String>	getKeys()	Returns the keySet() of index.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

index

private java.util.TreeMap<java.lang.String,IndexEntry> index

A TreeMap with a String key mapped on to an Index Entry value that acts as the index for the document. The word of the IndexEntry acts as the key to find the IndexEntry.

Constructor Detail

DocumentIndex

public DocumentIndex()

Constructs a DocumentIndex by initializing the index field to a default TreeMap

Method Detail

getKeys

public java.util.Set<java.lang.String> getKeys()

Returns the keySet() of index. This allows access to a TreeMap function needed for the IndexMaker class.

Returns:

the keySet() of the TreeMap that holds the IndexEntries.

See Also:

IndexMaker

getEntry

public IndexEntry getEntry(java.lang.String key)

This method returns the corresponding IndexEntry to the key provided if the key set does contain the key. The method was created for its use within IndexMaker, and, as such, it is unlikely it will return null within that class because IndexMaker uses it with the key set provided by getKeys()

Parameters:

key - a String that if it is found within the key set for the TreeMap will return the corresponding IndexEntry for the key

Returns:

an IndexEntry if index has key and null if IndexEntry does not

See Also:

IndexMaker

addWord

public void addWord(java.lang.String word,
                    int num)

Adds word to the index by taking the word parameter and checking if it is already in index. If it is, the method will add the given int to the TreeSet of line numbers for the corresponding IndexEntry. If not, the method will add a new IndexEntry to the index with word as the value and num as the first line number it appears on. Words when added to the index are formatted as uppercase.

Parameters:

word - the word to be added

num - the line number the word was found on

See Also:

addAllWords(String str, int num)

addAllWords

public void addAllWords(java.lang.String str,
                        int num)

This method adds all words in a given String to the index. The method is intended to take a line of a document and add all of the new words on the line to the index and add the number of the line to the TreeSet of line numbers for words already in the index. The method uses the addWord(String word, int num) method of this class to do so. Words when added to the index are formatted as uppercase. The method utilizes regex to ensure that words do not include numbers or unnecessary punctuation.

Parameters:

str - String that contains the words to be added to index.

num - number of the line of the document str is