Class AbstractSearchTool
- Direct Known Subclasses:
AbstractSearchTool
Abstract view tool for doing "searching" and robust pagination of search results. The goal here is to provide a simple and uniform API for "search tools" that can be used in velocity templates (or even a standard Search.vm template). In particular, this class provides good support for result pagination and some very simple result caching.
Usage:
To use this class, you must extend it and implement
the executeQuery(Object) method.
The setCriteria(Object) method takes an Object in order to allow the search criteria to meet your needs. Your criteria may be as simple as a single string, an array of strings, or whatever you like. The value passed into this method is that which will ultimately be passed into executeQuery(Object) to perform the search and return a list of results. A simple implementation might be like:
protected List executeQuery(Object crit) { return MyDbUtils.getFooBarsMatching((String)crit); }
Here's an example of how your subclass would be used in a template:
<form name="search" method="get" action="$link.setRelative('search.vm')"> <input type="text"name="find" value="$!search.criteria"> <input type="submit" value="Find"> </form> #if( $search.hasItems() ) Showing $!search.pageDescription<br> #set( $i = $search.index ) #foreach( $item in $search.page ) ${i}. $!item <br> #set( $i = $i + 1 ) #end <br> #if ( $search.pagesAvailable > 1 ) #set( $pagelink = $link.setRelative('search.vm').addQueryData("find",$!search.criteria).addQueryData("show",$!search.itemsPerPage) ) #if( $search.prevIndex ) <a href="$pagelink.addQueryData('index',$!search.prevIndex)">Prev</a> #end #foreach( $index in $search.slip ) #if( $index == $search.index ) <b>$search.pageNumber</b> #else <a href="$pagelink.addQueryData('index',$!index)">$!search.getPageNumber($index)</a> #end #end #if( $search.nextIndex ) <a href="$pagelink.addQueryData('index',$!search.nextIndex)">Next</a> #end #end #elseif( $search.criteria ) Sorry, no matches were found for "$!search.criteria". #else Please enter a search term #endThe output of this might look like:
Showing 1-5 of 8
1. foo
2. bar
3. blah
4. woogie
5. baz
1 2 Next
Example toolbox.xml configuration:
<tools> <toolbox scope="request"> <tool class="com.foo.tools.MySearchTool"/> </toolbox> </tools>
- Since:
- VelocityTools 2.0
- Version:
- $Revision: 591088 $ $Date: 2007-11-01 10:11:41 -0700 (Thu, 01 Nov 2007) $
- Author:
- Nathan Bubna
-
Nested Class Summary
Nested ClassesModifier and TypeClassDescriptionstatic class
Simple utility class to hold a criterion and its result list. -
Field Summary
FieldsModifier and TypeFieldDescriptionprivate Object
private String
static final String
protected org.apache.velocity.runtime.log.Log
protected static final String
the key under which StoredResults are kept in sessionFields inherited from class org.apache.velocity.tools.view.PagerTool
DEFAULT_INDEX_KEY, DEFAULT_ITEMS_PER_PAGE, DEFAULT_ITEMS_PER_PAGE_KEY, DEFAULT_NEW_ITEMS_KEY, DEFAULT_SLIP_SIZE, DEFAULT_SLIP_SIZE_KEY, session, STORED_ITEMS_KEY
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Constructor Summary
Constructors -
Method Summary
Modifier and TypeMethodDescriptionprotected abstract List
executeQuery
(Object criteria) Executes a query for the specified criteria.Return the criteria object for this request.getItems()
Gets the results for the given criteria either in memory or by performing a new query for them.protected List
Retrieves stored search items (if any) from the user's session attributes.protected AbstractSearchTool.StoredResults
Retrieves stored search results (if any) from the user's session attributes.void
reset()
Sets the criteria and results to null, page index to zero, and items per page to the default.void
setCriteria
(Object criteria) Sets the criteria for this search.void
setCriteriaKey
(String key) void
setLog
(org.apache.velocity.runtime.log.Log log) protected void
setStoredItems
(List items) Stores current search items in the user's session attributes (if one currently exists) in order to do efficient result pagination.protected void
Stores current search results in the user's session attributes (if one currently exists) in order to do efficient result pagination.void
setup
(HttpServletRequest request) Sets the criteria *if* it is set in the request parameters.Methods inherited from class org.apache.velocity.tools.view.PagerTool
getCreateSession, getFirstIndex, getIndex, getIndexKey, getItemsPerPage, getItemsPerPageKey, getLastIndex, getNewItemsKey, getNextIndex, getPage, getPageDescription, getPageNumber, getPageNumber, getPagesAvailable, getPrevIndex, getSlip, getSlipSize, getSlipSizeKey, getTotal, hasItems, setCreateSession, setIndex, setIndexKey, setItems, setItemsPerPage, setItemsPerPageKey, setNewItemsKey, setRequest, setSlipSize, setSlipSizeKey
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Field Details
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DEFAULT_CRITERIA_KEY
- See Also:
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STORED_RESULTS_KEY
the key under which StoredResults are kept in session -
LOG
protected org.apache.velocity.runtime.log.Log LOG -
criteriaKey
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criteria
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Constructor Details
-
AbstractSearchTool
public AbstractSearchTool()
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Method Details
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setLog
public void setLog(org.apache.velocity.runtime.log.Log log) -
setup
public void setup(HttpServletRequest request) Sets the criteria *if* it is set in the request parameters. -
setCriteriaKey
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getCriteriaKey
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reset
public void reset()Sets the criteria and results to null, page index to zero, and items per page to the default. -
setCriteria
Sets the criteria for this search.- Parameters:
criteria
- - the criteria used for this search
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getCriteria
Return the criteria object for this request. (for a simple search mechanism, this will typically be just a java.lang.String)- Returns:
- criteria object
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getItems
Gets the results for the given criteria either in memory or by performing a new query for them. If the criteria is null, an empty list will be returned. -
getStoredItems
Description copied from class:PagerTool
Retrieves stored search items (if any) from the user's session attributes.- Overrides:
getStoredItems
in classPagerTool
- Returns:
- the
List
retrieved from memory
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setStoredItems
Description copied from class:PagerTool
Stores current search items in the user's session attributes (if one currently exists) in order to do efficient result pagination.Override this to store search items somewhere besides the HttpSession or to prevent storage of items across requests. In the former situation, you must also override getStoredItems().
- Overrides:
setStoredItems
in classPagerTool
- Parameters:
items
- theList
to be stored
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executeQuery
Executes a query for the specified criteria.This method must be implemented! A simple implementation might be something like:
protected List executeQuery(Object crit) { return MyDbUtils.getFooBarsMatching((String)crit); }
- Returns:
- a
List
of results for this query
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getStoredResults
Retrieves stored search results (if any) from the user's session attributes.- Returns:
- the
AbstractSearchTool.StoredResults
retrieved from memory
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setStoredResults
Stores current search results in the user's session attributes (if one currently exists) in order to do efficient result pagination.Override this to store search results somewhere besides the HttpSession or to prevent storage of results across requests. In the former situation, you must also override getStoredResults().
- Parameters:
results
- theAbstractSearchTool.StoredResults
to be stored
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