AbstractQuery (Dragontool 1.3.3 API)

java.lang.Object
- dragon.onlinedb.AbstractQuery

All Implemented Interfaces:

ArticleQuery, CollectionReader

Direct Known Subclasses:

AbstractSearchEngine, AmazonCatalogQuery, AmazonReviewQuery, CiteULikeTagQuery, PubMedQuery
```
public abstract class AbstractQuery
extends Object
implements ArticleQuery
```
Abstract class for querying articles from a data source

Copyright: Copyright (c) 2005

Company: IST, Drexel University

Version:

1.0

Author:

Davis Zhou

Field Summary

Fields
Modifier and Type	Field and Description
`protected int`	`articleNum`
`protected Article`	`curArticle`
`protected int`	`curArticleNo`
`protected int`	`curPageNo`
`protected int`	`curPageWidth`
`protected int`	`pageNum`
`protected int`	`pageWidth`
`protected ArticleParser`	`parser`

Constructor Summary

Constructors
Constructor and Description

AbstractQuery(int pageWidth)

Constructors
Constructor and Description
`AbstractQuery(int pageWidth)`

Method Summary

All Methods Instance Methods Abstract Methods Concrete Methods
Modifier and Type	Method and Description
`void`	`close()` Closes the collection reader and releases all occupied resources.
`Article`	`getArticle()` read out the article the current pointer points to.
`protected abstract Article`	`getArticle(int articleNo)`
`String`	`getArticleKey()` In some cases, retrieval of an article is very expensive.
`ArticleParser`	`getArticleParser()` Gets the article parser of the collection reader
`int`	`getCurPageNo()`
`int`	`getCurPageWidth()`
`Article`	`getNextArticle()` Collection readers only support forward-only read mode.
`int`	`getPageNum()`
`int`	`getPageWidth()`
`int`	`getTotalArticleNum()`
`boolean`	`loadCollection(String collectionPath, String collectionName)`
`boolean`	`moveToArticle(int paperNo)` Move the pointer to the give position of the current page.
`boolean`	`moveToNextArticle()` The pointer will be set on the next article.
`boolean`	`moveToNextPage()` Move to the next page and the pointer is set on the first article of the page.
`void`	`restart()` The collection reader supports forward-only read mode.
`void`	`setArticleParser(ArticleParser parser)` Sets the article parse for the collection reader
`int`	`size()` The size of the collection.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface dragon.onlinedb.ArticleQuery
initQuery, moveToPage, setSearchTerm

Methods inherited from interface dragon.onlinedb.CollectionReader
getArticleByKey, supportArticleKeyRetrieval

- Field Detail
  - curPageNo
```
protected int curPageNo
```
  - curArticleNo
```
protected int curArticleNo
```
  - pageNum
```
protected int pageNum
```
  - articleNum
```
protected int articleNum
```
  - pageWidth
```
protected int pageWidth
```
  - curPageWidth
```
protected int curPageWidth
```
  - curArticle
```
protected Article curArticle
```
  - parser
```
protected ArticleParser parser
```
- Constructor Detail
  - AbstractQuery
```
public AbstractQuery(int pageWidth)
```
- Method Detail
  - getArticle
```
protected abstract Article getArticle(int articleNo)
```
  - getCurPageNo
```
public int getCurPageNo()
```
    Specified by:
    
    getCurPageNo in interface ArticleQuery
  - moveToNextPage
```
public boolean moveToNextPage()
```
    Description copied from interface: ArticleQuery
    
    Move to the next page and the pointer is set on the first article of the page.
    
    Specified by:
    
    moveToNextPage in interface ArticleQuery
    
    Returns:
    
    false if it reached the last page already.
  - getTotalArticleNum
```
public int getTotalArticleNum()
```
  - getPageNum
```
public int getPageNum()
```
    Specified by:
    
    getPageNum in interface ArticleQuery
  - getPageWidth
```
public int getPageWidth()
```
    Specified by:
    
    getPageWidth in interface ArticleQuery
  - getCurPageWidth
```
public int getCurPageWidth()
```
    Specified by:
    
    getCurPageWidth in interface ArticleQuery
    
    Returns:
    
    number of papers in the current page.
  - moveToNextArticle
```
public boolean moveToNextArticle()
```
    Description copied from interface: ArticleQuery
    
    The pointer will be set on the next article. After call the method of initQuery, one should call this method before you call getArticle to get the first article.
    
    Specified by:
    
    moveToNextArticle in interface ArticleQuery
    
    Returns:
    
    true if the current pointer is not on the last article.
  - moveToArticle
```
public boolean moveToArticle(int paperNo)
```
    Description copied from interface: ArticleQuery
    
    Move the pointer to the give position of the current page.
    
    Specified by:
    
    moveToArticle in interface ArticleQuery
    
    Parameters:
    
    paperNo - the position of the article in the current page.
    
    Returns:
    
    true if the position is within the scope of the current page.
  - getArticle
```
public Article getArticle()
```
    Description copied from interface: ArticleQuery
    
    read out the article the current pointer points to.
    
    Specified by:
    
    getArticle in interface ArticleQuery
    
    Returns:
    
    an article
  - getArticleKey
```
public String getArticleKey()
```
    Description copied from interface: ArticleQuery
    
    In some cases, retrieval of an article is very expensive. Thus, one may check the key (unique document entry number) first. If the article is of interest, one will retrieve this article.
    
    Specified by:
    
    getArticleKey in interface ArticleQuery
    
    Returns:
    
    the key of the article the current pointer points to.
  - loadCollection
```
public boolean loadCollection(String collectionPath,
                              String collectionName)
```
  - getArticleParser
```
public ArticleParser getArticleParser()
```
    Description copied from interface: CollectionReader
    
    Gets the article parser of the collection reader
    
    Specified by:
    
    getArticleParser in interface CollectionReader
    
    Returns:
    
    the article parser
  - setArticleParser
```
public void setArticleParser(ArticleParser parser)
```
    Description copied from interface: CollectionReader
    
    Sets the article parse for the collection reader
    
    Specified by:
    
    setArticleParser in interface CollectionReader
    
    Parameters:
    
    parser - the article parser
  - getNextArticle
```
public Article getNextArticle()
```
    Description copied from interface: CollectionReader
    
    Collection readers only support forward-only read mode. When one call this method after calling restart method or creating the collection reader, it actually return the first article of the collection.
    
    Specified by:
    
    getNextArticle in interface CollectionReader
    
    Returns:
    
    the next article
  - close
```
public void close()
```
    Description copied from interface: CollectionReader
    
    Closes the collection reader and releases all occupied resources.
    
    Specified by:
    
    close in interface CollectionReader
  - restart
```
public void restart()
```
    Description copied from interface: CollectionReader
    
    The collection reader supports forward-only read mode. If one wants to scan the collection for the second time, it is required to call this method. Otherwise when one getNextArticle method, it always return null.
    
    Specified by:
    
    restart in interface CollectionReader
  - size
```
public int size()
```
    Description copied from interface: CollectionReader
    
    The size of the collection. If the returned size is -1, it means the exact size is unknown.
    
    Specified by:
    
    size in interface CollectionReader
    
    Returns:
    
    the size of the collection.

Class AbstractQuery

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Methods inherited from interface dragon.onlinedb.ArticleQuery

Methods inherited from interface dragon.onlinedb.CollectionReader

Field Detail

curPageNo

curArticleNo

pageNum

articleNum

pageWidth

curPageWidth

curArticle

parser

Constructor Detail

AbstractQuery

Method Detail

getArticle

getCurPageNo

moveToNextPage

getTotalArticleNum

getPageNum

getPageWidth

getCurPageWidth

moveToNextArticle

moveToArticle

getArticle

getArticleKey

loadCollection

getArticleParser

setArticleParser

getNextArticle

close

restart

size