derby
Class DBHandler

java.lang.Object
  derby.DBHandler

public class DBHandler
extends java.lang.Object

The DBHandler acts as the intermediary between the database and the rest of the system. While the DBHandler implements SQL commands, the Database is responsible for the actual execution. The handler acts as a translator, taking SQL commands and converting them into meaningful objects in the model. Rep invarients -Each user may have only one feed for a given URL (Feeds may not be in multiple folders). -Folders may not have any siblings with the same name -No article may list the Trash as their parent feed -FeedID 0 does not exist in the DB; is the root node and all user's top level folders point to the root as their parent -Each user must have at least 3 feeds / folders: Subscribed Feeds, Outbox, and Trash -Min(FeedID) for a user is Subscribed Feeds -Min(FeedID)+1 for a user is the Outbox -Min(FeedID)+2 for a user is the Trash -Trash & outbox may only contain articles -Database may only have 3 tables: Feeds, Atricles, and Users -Every folder must have a distinct feedid -Every feed must have a distinct feedid -Every article must have a distinct articleid -Every user must have a distict username and userid -Only one user may be active at a time

Author:

zozer

Field Summary

private Feed	currentOutbox
private Folder	currentSF
private Feed	currentTrash
private int	currentUserID
private Database	db

Constructor Summary

DBHandler()
Upon construction, the DBHandler object creates a Database object.

Method Summary

private boolean	add(Article article, Feed feed) Adds an article to the specified feed in the database.
private void	add(Feed feed, Folder folder) Adds a feed to the specified folder in the database.
private void	add(Folder parent, Folder child) Adds a subfolder to a folder in the database.
private boolean	addArticlestoFeed(java.util.List<Article> list, Feed f) Adds a list of articles to a specified feed.
Feed	addFeed(Feed feed, Folder folder) Adds a feed to a folder in the database.
Folder	addFolder(Folder parent, Folder child) Adds a folder to another folder in the database.
boolean	addUser(java.lang.String userName, java.lang.String password) Adds a user to the database
private Article	articleUpdate(Article a, java.lang.String set) Modifies an article already in the database based on String.
boolean	copyArticle(Article source, Feed destination) Copies an article into a Feed
private java.lang.String	datetoString(java.util.Date d) Converts a date to a Timestamp friendly string.
private void	deleteArticles(Feed f) Deletes all articles from the specified feed in the database.
private void	deleteDB() Deletes all tables in the database, effectively reseting the DB to its original state.
private void	deleteFeed(Feed f) Deletes a feed from the database.
boolean	deleteFolder(Folder f) Deletes a folder from the database (permanently)
boolean	deleteUser(java.lang.String username, java.lang.String password) Delete's a user from the database.
boolean	emptyTrash() "Empties" the trash.
private Feed	feedUpdate(Feed f, java.lang.String set) Updates a field of a feed
java.util.List<java.lang.String>	getAllUsers() Gets a list of all usernames
private Article	getArticlebyFeedUAT(java.lang.String url, java.lang.String author, java.lang.String title, Feed feed, java.lang.String constraint) Gets an Article based on its URL, title, author, and the feed it's in.
private Article	getArticlebyID(int ID) Gets an Article based on its Article ID.
Article	getArticleRandom() Gets a random, unread article from the database.
private java.util.List<Article>	getArticles(java.lang.String constraint) Returns a list of articles satisfying the constraint.
java.util.List<Article>	getArticlesbyFeed(Feed feed) Retrieves a list of articles from the database that are in the specified feed (based on feedID).
private int	getArticlesCount(java.lang.String constraint) Returns a count of the number of articles in the database which meet the condition of the constraint.
java.util.List<Feed>	getChildrenFeeds(Folder f) Retrieves the Feeds which are children of a specified folder.
java.util.List<Folder>	getChildrenFolders(Folder f) Retrieves the Folders which are children of a specified folder.
java.lang.String	getCurrentUser() Returns the username of the current active user
int	getCurrentUserID() Returns the userid of the active user.
int	getCurrentUserView() Gets the viewid of the view of the current user
private Feed	getFeedbyID(int ID) Gets a Feed based on its Feed ID.
private Feed	getFeedbyURL(java.lang.String URL) Gets a Feed based on its URL.
private java.util.List<Feed>	getFeeds(java.lang.String constraint) Returns a list of Feed objects which satisfy the constraint.
java.util.List<Feed>	getFeedsAll() Gets all Feeds in the database for a given user.
java.util.List<Feed>	getFeedstoUpdate() Gets all the feeds to be updated in a given minute, based on absolute time, not the time since the program was started.
private Folder	getFolderbyID(int ID) Gets a Folder based on its FolderID.
private java.util.List<Folder>	getFolders(java.lang.String constraint) Returns a list of Folder objects which satisfy the constraint.
int	getNumberArticles(java.lang.String constraint) Returns a count of the number of articles in the database whose author, title, or contents contain a substring matching the constraint.
int	getNumberOfNewArticles(Feed feed) Retrieves the number of articles from the database that are unread and belong to the specified feed.
Feed	getOutbox() Gets the outbox feed
Feed	getParent(Article a) Retrieves the Feed which is the parent of the specified Article.
Folder	getParent(Feed f) Retrieves the Folder which is the parent of the specified Feed.
Folder	getParent(Folder f) Retrieves the Folder which is the parent of the specified Folder.
java.util.List<java.lang.Object>	getRoot() Retrieves the list of folders contained by the root folder.
Folder	getSubscribedFeeds() Gets the subscribed feeds folder
Feed	getTrash() Gets the Trash feed
java.util.List<Article>	getTrashArticles() Gets a list of the articles in the trash
int	getUserID(java.lang.String username) Gets a user's userid based on their username.
private void	insert(java.util.HashMap<java.lang.String,java.lang.String> values, java.lang.String table) Insert builds a string corresponding to a SQL insert of the specified row values into 'table' and executes that query.
Article	markRead(Article a) Set the read status of an article to read
Article	markUnread(Article a) Set the read status of an article to unread
boolean	moveFeed(Feed source, Folder destination) Moves a Feed from one parent folder to another
boolean	moveFolder(Folder source, Folder destination) Moves a subfolder from one parent to another
private boolean	repOK() Makes sure that the current state does not violate the representation invarient.
boolean	resetDB() Resets the database to its initial state
java.util.List<Article>	searchArticles(boolean byAuthor, boolean byTitle, boolean byContent, Feed feed, java.lang.String constraint) Gets a list of articles within a feed based on a search string.
java.util.List<Article>	searchArticles(boolean byAuthor, boolean byTitle, boolean byContent, java.lang.String constraint) Gets a list of articles based on a search string.
java.util.List<Article>	searchArticlesOrdered(boolean byAuthor, boolean byTitle, boolean byContent, java.lang.String constraint) Gets a list of articles based on a search string.
private java.sql.ResultSet	select(java.lang.String[] fields, java.lang.String table, java.lang.String constraints) Select compiles a string representing a SQL select query, executes that query, and then returns the ResultSet from that query.
boolean	setCurrentUser(java.lang.String userName, java.lang.String password) Sets the current, active user
boolean	setCurrentUserView(int i) Set the current user's active view
Article	setDelete(Article a) Permanently delete an article
Feed	setFeedTitle(Feed f, java.lang.String title) Sets the title a feed
Feed	setFeedUpdateInterval(Feed f, int i) Sets how often a feed will be automatically updated
Article	setRating(Article a, int i) Set the rating of an article to int i
Article	setReadTime(Article a, int i) Set the amount of time you spent reading an article.
Article	setTrash(Article a) Put an article in the Trash
Article	setUnTrash(Article a) Move an article out of the Trash
private void	setupDB() Runs a setup algorithm which creates the feeds, articles, and user tables, as well as the 'Subscribed Feeds' and 'Outbox' folders, which must exist on creation according to the Rep Invariant.
boolean	shutdown() Shuts down the database.
private void	startup() Database startup routine.
boolean	unSubscribe(Feed f) Unsubscribes a feed from the database.
boolean	updateAll(java.util.List<Feed> feedList) This takes a list of feeds and runs update feed for each of them.
Feed	updateFeed(Feed f) Takes a feed from the parser (so it should have its children articles but no id) and updates the database appropriately.
private boolean	userUpdate(java.lang.String userName, java.lang.String password, java.lang.String set) Updates a user's profile

Methods inherited from class java.lang.Object

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

Field Detail

db

private Database db

currentUserID

private int currentUserID

currentSF

private Folder currentSF

currentOutbox

private Feed currentOutbox

currentTrash

private Feed currentTrash

Constructor Detail

DBHandler

public DBHandler()
          throws DBHandlerException

Upon construction, the DBHandler object creates a Database object. This Database is where all data for the system is stored, and serves as the ultimate repository of information. The DBHandler automatically starts the DB on instantiation.

Throws:

DBHandlerException - if the database is not properly instantiated, if it fails to startup, or if it fails to setup.

Method Detail

setupDB

private void setupDB()
              throws DBException

Runs a setup algorithm which creates the feeds, articles, and user tables, as well as the 'Subscribed Feeds' and 'Outbox' folders, which must exist on creation according to the Rep Invariant.

Throws:

DBException - If any part of the setup fails

startup

private void startup()
              throws DBHandlerException

Database startup routine. Requires that the database be instantiated, however, this is taken care of when the DBHandler is instantiated.

Throws:

DBHandlerException - if DB fails to startup or setup.

shutdown

public boolean shutdown()
                 throws DBHandlerException

Shuts down the database.

Returns:

true if runs to completion

Throws:

DBHandlerException

deleteDB

private void deleteDB()
               throws DBException

Deletes all tables in the database, effectively reseting the DB to its original state.

Throws:

DBException - if any of the database operations fail

resetDB

public boolean resetDB()
                throws DBHandlerException

Resets the database to its initial state

Returns:

true if the database is successfully reset

Throws:

DBHandlerException - if any of

repOK

private boolean repOK()

Makes sure that the current state does not violate the representation invarient.

Returns:

true if none of the representation invarient conditions are violated

select

private java.sql.ResultSet select(java.lang.String[] fields,
                                  java.lang.String table,
                                  java.lang.String constraints)
                           throws DBHandlerException

Select compiles a string representing a SQL select query, executes that query, and then returns the ResultSet from that query. The fields array should be strings of the column names to be returned.

Parameters:

String[] - fields

String - table

String - constraints

Returns:

ResultSet (Never null)

Throws:

DBHandlerException - if fields or table are null, or if the database query corresponding to the select fails for some reason

insert

private void insert(java.util.HashMap<java.lang.String,java.lang.String> values,
                    java.lang.String table)
             throws DBHandlerException

Insert builds a string corresponding to a SQL insert of the specified row values into 'table' and executes that query.

Parameters:

HashMap(String - ColumnName, String Values)

String - Table

Throws:

DBHandlerException - if either the values or table are null, or if the database query corresponding to the select fails for some reason

getArticles

private java.util.List<Article> getArticles(java.lang.String constraint)
                                     throws DBHandlerException

Returns a list of articles satisfying the constraint. If no constraint is specified, all articles will be returned.

Parameters:

String - SQLconstraint (Has "Where"; Requires "AND")

Returns:

List(Article) (never null)

Throws:

DBHandlerException - if there is an error running the query or creating the article object

getArticlebyFeedUAT

private Article getArticlebyFeedUAT(java.lang.String url,
                                    java.lang.String author,
                                    java.lang.String title,
                                    Feed feed,
                                    java.lang.String constraint)
                             throws DBHandlerException

Gets an Article based on its URL, title, author, and the feed it's in. To search in all folders, 0 (the root node) should be passed as the last term, the FeedID. NOTE: inactive, deleted articles will be returned.

Parameters:

String - url

String - author

String - title

int - feedID

String - Constraint

Returns:

Article, unless no article is found, in which case the result is null

Throws:

DBHandlerException - if there is an error retrieving the articles from the database, if more than one article is returned by the search, or if the feed passed in does not exist in the database

getArticlebyID

private Article getArticlebyID(int ID)
                        throws DBHandlerException

Gets an Article based on its Article ID.

Parameters:

int - ID

Returns:

Article

Throws:

DBHandlerException - if there is an error retrieving the article from the database or if more than one article is returned by the search

getArticlesbyFeed

public java.util.List<Article> getArticlesbyFeed(Feed feed)
                                          throws DBHandlerException

Retrieves a list of articles from the database that are in the specified feed (based on feedID). Only active, non-deleted articles are returned.

Parameters:

Feed -

Returns:

List(Article)

Throws:

DBHandlerException - if there is an error retrieving the articles from the database or if the Feed provided has no ID

getTrashArticles

public java.util.List<Article> getTrashArticles()
                                         throws DBHandlerException

Gets a list of the articles in the trash

Returns:

List

in the Trash

Throws:

DBHandlerException - if the database query fails

searchArticles

public java.util.List<Article> searchArticles(boolean byAuthor,
                                              boolean byTitle,
                                              boolean byContent,
                                              java.lang.String constraint)
                                       throws DBHandlerException

Gets a list of articles based on a search string. The search looks for the string in the author, title, and content of the article, depending on the flags set by the booleans. Only active, non-deleted articles are returned.

Parameters:

boolean - byAuthor

boolean - byTitle

boolean - byContent

String - searchConstraint

Returns:

List (articles) matching the constraint in the fields specified

Throws:

DBHandlerException - if no search fields are selected or if the database fails while performing the search.

searchArticles

public java.util.List<Article> searchArticles(boolean byAuthor,
                                              boolean byTitle,
                                              boolean byContent,
                                              Feed feed,
                                              java.lang.String constraint)
                                       throws DBHandlerException

Gets a list of articles within a feed based on a search string. The search looks for the string in the author, title, and content of the article, depending on the flags set by the booleans. Only active, non-deleted articles are returned.

Parameters:

boolean - byAuthor

boolean - byTitle

boolean - byContent

feed -

String - searchConstraint

Returns:

List (articles) matching the constraint in the fields specified

Throws:

DBHandlerException - if no search fields are selected or if the database fails while performing the search.

searchArticlesOrdered

public java.util.List<Article> searchArticlesOrdered(boolean byAuthor,
                                                     boolean byTitle,
                                                     boolean byContent,
                                                     java.lang.String constraint)
                                              throws DBHandlerException

Gets a list of articles based on a search string. The search looks for the string in the author, title, and content of the article, depending on the flags set by the booleans. Only active, non-deleted articles are returned.

Parameters:

boolean - byAuthor

boolean - byTitle

boolean - byContent

String - searchConstraint

Returns:

List (articles) matching the constraint in the fields specified

Throws:

DBHandlerException - if no search fields are selected or if the database fails while performing the search.

getArticleRandom

public Article getArticleRandom()
                         throws DBHandlerException

Gets a random, unread article from the database. Only active, non-deleted articles are returned.

Returns:

Article

Throws:

DBHandlerException - if there is an error retrieving the articles from the database or if the user has no articles from which to choose a random one.

getFeeds

private java.util.List<Feed> getFeeds(java.lang.String constraint)
                               throws DBHandlerException

Returns a list of Feed objects which satisfy the constraint. If no constraint is specified, all Feeds will be returned.

Parameters:

String - SQLconstraint (Has "Where"; Requires "AND")

Returns:

List(Feed) (never null)

Throws:

DBHandlerException - if there is an error running the query or an error creating the Feed object

getFeedbyID

private Feed getFeedbyID(int ID)
                  throws DBHandlerException

Gets a Feed based on its Feed ID.

Parameters:

int - FeedID

Returns:

Feed

Throws:

DBHandlerException - if there is an error retrieving the feed from the database, if the feedid is not unique, or if a feed with the specified feedid does not exist.

getFeedbyURL

private Feed getFeedbyURL(java.lang.String URL)
                   throws DBHandlerException

Gets a Feed based on its URL.

Parameters:

String - URL

Returns:

Feed

Throws:

DBHandlerException - if there is an error retrieving the feed from the database or if a feed with feedurl URL does not exist.

getParent

public Feed getParent(Article a)
               throws DBHandlerException

Retrieves the Feed which is the parent of the specified Article.

Parameters:

Article -

Returns:

Feed

Throws:

DBHandlerException - if there is an error retrieving the a unique parent Feed from the database or if an Article with the specified articleid does not exist in the database.

getChildrenFeeds

public java.util.List<Feed> getChildrenFeeds(Folder f)
                                      throws DBHandlerException

Retrieves the Feeds which are children of a specified folder.

Parameters:

Folder -

Returns:

List(Feed)

Throws:

DBHandlerException - if there is an error retrieving the Feeds from the database or if there is no Folder with the specified folderid

getFeedsAll

public java.util.List<Feed> getFeedsAll()
                                 throws DBHandlerException

Gets all Feeds in the database for a given user.

Returns:

List(Feed)

Throws:

DBHandlerException - if there is an error retrieving the feeds from the database.

getFeedstoUpdate

public java.util.List<Feed> getFeedstoUpdate()
                                      throws DBHandlerException

Gets all the feeds to be updated in a given minute, based on absolute time, not the time since the program was started.

Returns:

List(Feed)

Throws:

DBHandlerException - if there is an error retrieving the feeds from the database.

getFolders

private java.util.List<Folder> getFolders(java.lang.String constraint)
                                   throws DBHandlerException

Returns a list of Folder objects which satisfy the constraint. If no constraint is specified, all Folders will be returned.

Parameters:

String - SQLconstraint (Has "Where"; Requires "AND ")

Returns:

List(Folder) (never null)

Throws:

DBHandlerException - if there is an error running the query or an error creating the Folder object

getFolderbyID

private Folder getFolderbyID(int ID)
                      throws DBHandlerException

Gets a Folder based on its FolderID.

Parameters:

int - FolderID

Returns:

Folder

Throws:

DBHandlerException - if there is an error retrieving the Folder from the database or if a Folder with the specified FolderID does not exist.

getParent

public Folder getParent(Feed f)
                 throws DBHandlerException

Retrieves the Folder which is the parent of the specified Feed.

Parameters:

Feed -

Returns:

Folder

Throws:

DBHandlerException - if there is an error retrieving the a unique parent Folder from the database or if a Feed the specified feedid does not exist in the database.

getParent

public Folder getParent(Folder f)
                 throws DBHandlerException

Retrieves the Folder which is the parent of the specified Folder.

Parameters:

Folder -

Returns:

Folder

Throws:

DBHandlerException - if there is an error retrieving the a unique parent Folder from the database or if a Folder the specified feedid does not exist in the database.

getChildrenFolders

public java.util.List<Folder> getChildrenFolders(Folder f)
                                          throws DBHandlerException

Retrieves the Folders which are children of a specified folder.

Parameters:

Folder -

Returns:

List(Folder)

Throws:

DBHandlerException - if there is an error retrieving the Folders from the database or if a Folder with folderid FolderID does not exist.

getRoot

public java.util.List<java.lang.Object> getRoot()
                                         throws DBHandlerException

Retrieves the list of folders contained by the root folder.

Returns:

List(Objcect)

Throws:

DBHandlerException - or if there is an error retrieving the Subscribed Feeds Folder, Outbox Feed, or Trash Feed from the database

getSubscribedFeeds

public Folder getSubscribedFeeds()
                          throws DBHandlerException

Gets the subscribed feeds folder

Returns:

Folder outbox

Throws:

DBHandlerException - if the database query fails or if the folder is not unique for the user

getOutbox

public Feed getOutbox()
               throws DBHandlerException

Gets the outbox feed

Returns:

Folder outbox

Throws:

DBHandlerException - if the database query fails or if the feed is not unique for the user

getTrash

public Feed getTrash()
              throws DBHandlerException

Gets the Trash feed

Returns:

Feed trash

Throws:

DBHandlerException - if the database query fails or if the feed is not unique for the user

getUserID

public int getUserID(java.lang.String username)
              throws DBHandlerException

Gets a user's userid based on their username.

Parameters:

String - username

Returns:

int Userid

Throws:

DBHandlerException - if the database query fails, or if there is more than one or no user with the specified username

getCurrentUser

public java.lang.String getCurrentUser()
                                throws DBHandlerException

Returns the username of the current active user

Returns:

String username

Throws:

DBHandlerException - if the database query fails, or if there is more than one or no active

getCurrentUserID

public int getCurrentUserID()
                     throws DBHandlerException

Returns the userid of the active user.

Returns:

int userid

Throws:

DBHandlerException - if the database query fails, or if there is more than one or no user with the specified username or userid

getAllUsers

public java.util.List<java.lang.String> getAllUsers()
                                             throws DBHandlerException

Gets a list of all usernames

Returns:

List(String username) (never null)

Throws:

DBHandlerException - if the database query fails

getCurrentUserView

public int getCurrentUserView()
                       throws DBHandlerException

Gets the viewid of the view of the current user

Returns:

int viewid

Throws:

DBHandlerException - if the database query fails or if there is more than one active user

getArticlesCount

private int getArticlesCount(java.lang.String constraint)
                      throws DBException

Returns a count of the number of articles in the database which meet the condition of the constraint.

Parameters:

String - constraint

Returns:

int Count(Articles)

Throws:

DBException - if the database query fails

getNumberArticles

public int getNumberArticles(java.lang.String constraint)
                      throws DBHandlerException

Returns a count of the number of articles in the database whose author, title, or contents contain a substring matching the constraint.

Parameters:

String - constraint

Returns:

int Count(Articles) that meet the constraint

Throws:

DBHandlerException - if the database query fails or if the contraint is empty

getNumberOfNewArticles

public int getNumberOfNewArticles(Feed feed)
                           throws DBHandlerException

Retrieves the number of articles from the database that are unread and belong to the specified feed.

Parameters:

feed -

Returns:

int

Throws:

DBHandlerException - if there is an error retrieving the articles from the database or if the Feed provided has no ID

add

private boolean add(Article article,
                    Feed feed)
             throws DBHandlerException

Adds an article to the specified feed in the database.

Parameters:

Article -

Feed -

Returns:

boolean true if runs to completion

Throws:

DBHandlerException - if the database query corresponding to the insert fails or if the feed isn't in the database.

addArticlestoFeed

private boolean addArticlestoFeed(java.util.List<Article> list,
                                  Feed f)
                           throws DBHandlerException

Adds a list of articles to a specified feed.

Parameters:

List - (Article)

Feed -

Returns:

boolean true if runs to completion

Throws:

DBHandlerException - if the database query fails or if the destination feed does not exist

copyArticle

public boolean copyArticle(Article source,
                           Feed destination)
                    throws DBHandlerException

Copies an article into a Feed

Parameters:

Article -

Feed - destination

Returns:

true if the article is successfully added; false otherwise

Throws:

DBHandlerException - if the destination Feed does not exist, or if the database operation fails

add

private void add(Feed feed,
                 Folder folder)
          throws DBHandlerException

Adds a feed to the specified folder in the database.

Parameters:

Feed -

Folder -

Throws:

DBHandlerException - if the database query corresponding to the insert fails or if the destination folder doesn't exist in the database.

addFeed

public Feed addFeed(Feed feed,
                    Folder folder)
             throws DBHandlerException

Adds a feed to a folder in the database.

Parameters:

Feed -

Folder -

Returns:

Feed (with ID)

Throws:

DBHandlerException - if the feed already exists in the database, if the feed is not successfully added, or if the feed does not contain any articles

add

private void add(Folder parent,
                 Folder child)
          throws DBHandlerException

Adds a subfolder to a folder in the database.

Parameters:

Folder - parent

Folder - child

Throws:

DBHandlerException - if the database query corresponding to the insert fails or if the parent isn't in the database.

addFolder

public Folder addFolder(Folder parent,
                        Folder child)
                 throws DBHandlerException

Adds a folder to another folder in the database.

Parameters:

Folder - parent

Folder - child

Returns:

Updated Folder parent

Throws:

DBHandlerException - if the parent does not exist, if the database addition fails, or if the folder has the same name as a potential sibling (Folder at the same depth).

addUser

public boolean addUser(java.lang.String userName,
                       java.lang.String password)
                throws DBHandlerException

Adds a user to the database

Parameters:

String - userName

String - password

Returns:

ture if runs to completion

Throws:

DBHandlerException - if the user is already in the DB or if the DB inserts fail

articleUpdate

private Article articleUpdate(Article a,
                              java.lang.String set)
                       throws DBHandlerException

Modifies an article already in the database based on String.

Parameters:

Article - a

String - (includs "set"; requires 'field = value')

Returns:

Updated Article a

Throws:

DBHandlerException - if article a does not exist or is non-unique in the database, or if the database update operation fails

markRead

public Article markRead(Article a)
                 throws DBHandlerException

Set the read status of an article to read

Parameters:

Article - a

Returns:

Updated Article a

Throws:

DBHandlerException - if article a does not exist or is non-unique in the database, or if the database update operation fails

markUnread

public Article markUnread(Article a)
                   throws DBHandlerException

Set the read status of an article to unread

Parameters:

Article - a

Returns:

Updated Article a

Throws:

DBHandlerException - if article a does not exist or is non-unique in the database, or if the database update operation fails

setRating

public Article setRating(Article a,
                         int i)
                  throws DBHandlerException

Set the rating of an article to int i

Parameters:

Article - a

Returns:

Updated Article a

Throws:

DBHandlerException - if article a does not exist or is non-unique in the database, or if the database update operation fails

setReadTime

public Article setReadTime(Article a,
                           int i)
                    throws DBHandlerException

Set the amount of time you spent reading an article.

Parameters:

Article - a

int - i The read time (amount of time spent reading article).

Returns:

Updated Article a

Throws:

DBHandlerException - if article a does not exist or is non-unique in the database, or if the database update operation fails

setTrash

public Article setTrash(Article a)
                 throws DBHandlerException

Put an article in the Trash

Parameters:

Article - a

Returns:

Updated Article a

Throws:

DBHandlerException - if article a does not exist or is non-unique in the database, or if the database update operation fails

setUnTrash

public Article setUnTrash(Article a)
                   throws DBHandlerException

Move an article out of the Trash

Parameters:

Article - a

Returns:

Updated Article a

Throws:

DBHandlerException - if article a does not exist or is non-unique in the database, or if the database update operation fails

setDelete

public Article setDelete(Article a)
                  throws DBHandlerException

Permanently delete an article

Parameters:

Article - a

Returns:

Updated Article a

Throws:

DBHandlerException - if article a does not exist or is non-unique in the database, or if the database update operation fails

emptyTrash

public boolean emptyTrash()
                   throws DBHandlerException

"Empties" the trash. Articles remain in the database (but are invisible) until cleanup() is run. Should return a List(Article) with no elements if it runs to completetion

Returns:

boolean True if runs to completion

Throws:

DBHandlerException - if there is an error running the query to empty the trash or an error getting the contents of the Trash after emptying it.

feedUpdate

private Feed feedUpdate(Feed f,
                        java.lang.String set)
                 throws DBHandlerException

Updates a field of a feed

Parameters:

Feed - f

String - set (includs "set"; requires 'field = value')

Returns:

updatedFeed f

Throws:

DBHandlerException - of the feed does not exist in the DB or if the DB operation fails

setFeedUpdateInterval

public Feed setFeedUpdateInterval(Feed f,
                                  int i)
                           throws DBHandlerException

Sets how often a feed will be automatically updated

Parameters:

Feed - f

int - updateInterval (minutes)

Returns:

updatedFeed f

Throws:

DBHandlerException

setFeedTitle

public Feed setFeedTitle(Feed f,
                         java.lang.String title)
                  throws DBHandlerException

Sets the title a feed

Parameters:

Feed - f

String - newTitle

Returns:

updatedFeed f

Throws:

DBHandlerException

moveFeed

public boolean moveFeed(Feed source,
                        Folder destination)
                 throws DBHandlerException

Moves a Feed from one parent folder to another

Parameters:

Feed - source

Folder - destination

Returns:

boolean true if runs to completion

Throws:

DBHandlerException - if the source Feed or destination Folder does not exist, or if the database update operation fails

updateFeed

public Feed updateFeed(Feed f)
                throws DBHandlerException

Takes a feed from the parser (so it should have its children articles but no id) and updates the database appropriately. Returns a new feed object that has been updated appropriately.

Parameters:

Feed - f

Returns:

UpdatedFeed f

Throws:

DBHandlerException - if the feed being updated is not already in the DB, if there is a problem adding the new articles to the DB, or if there is a problem getting the new feed after the update

updateAll

public boolean updateAll(java.util.List<Feed> feedList)
                  throws DBHandlerException

This takes a list of feeds and runs update feed for each of them. List(Feed) feedList should come from the parser, and each feed must return true for knowsChildren to ensure that update to work properly.

Parameters:

List(Feed) - feedList

Returns:

boolean true if runs to completion

Throws:

DBHandlerException - if there is a problem updating any feed in the list of feeds (including attempting to update a non-existant feed).

moveFolder

public boolean moveFolder(Folder source,
                          Folder destination)
                   throws DBHandlerException

Moves a subfolder from one parent to another

Parameters:

Folder - source

Folder - destination

Returns:

boolean true if runs to completion

Throws:

DBHandlerException - if the source or destination Folders do not exist, or if the database update operation fails

userUpdate

private boolean userUpdate(java.lang.String userName,
                           java.lang.String password,
                           java.lang.String set)
                    throws DBHandlerException

Updates a user's profile

Parameters:

String - userName

String - password

String - set (includs "set"; requires 'field = value')

Returns:

true if runs to completion

Throws:

DBHandlerException - if the user is not in the database or if the DB update fails

setCurrentUser

public boolean setCurrentUser(java.lang.String userName,
                              java.lang.String password)
                       throws DBHandlerException

Sets the current, active user

Parameters:

String - userName

String - password

Returns:

true if runs to completion

Throws:

DBHandlerException - if the user does not exist or if the DB operation fails

setCurrentUserView

public boolean setCurrentUserView(int i)
                           throws DBHandlerException

Set the current user's active view

Parameters:

int - viewid

Returns:

true if runs to completion

Throws:

DBHandlerException - if the user is not in the database or if the DB update operation fails

deleteArticles

private void deleteArticles(Feed f)
                     throws DBHandlerException

Deletes all articles from the specified feed in the database.

Parameters:

Feed - f

Throws:

DBHandlerException - if the database operation fails, or if the feed has no valid ID

deleteFeed

private void deleteFeed(Feed f)
                 throws DBHandlerException

Deletes a feed from the database.

Parameters:

Feed - f

Throws:

DBHandlerException - if the database operation fails, if the feed has no valid ID, or if the feed the user is trying to delete is Subscribed Feeds, the outbox, or the trash

unSubscribe

public boolean unSubscribe(Feed f)
                    throws DBHandlerException

Unsubscribes a feed from the database. Deletes the specified feed and all its articles.

Parameters:

Feed -

Returns:

boolean true if both the articles and feed are successfully removed

Throws:

DBHandlerException - if the feed does not exist, or if there is a error performing the database operation

deleteFolder

public boolean deleteFolder(Folder f)
                     throws DBHandlerException

Deletes a folder from the database (permanently)

Parameters:

Folder -

Returns:

boolean true if runs to completion

Throws:

DBHandlerException - if the folder is not in the database, if the database operation fails, or if the folder passed is the 'Subscribed Feeds' folder

deleteUser

public boolean deleteUser(java.lang.String username,
                          java.lang.String password)
                   throws DBHandlerException

Delete's a user from the database. as well as their feeds, folders, and articles

Parameters:

String - username

String - password

Returns:

true if runs to completion

Throws:

DBHandlerException - if the user does not exist or if the DB deletion operations fail

datetoString

private java.lang.String datetoString(java.util.Date d)

Converts a date to a Timestamp friendly string.

Parameters:

Date -

Returns:

Timestamp(Date) --> String