在appengine上用compass来集成lucene实现全文搜索

using a compass + JDO Search on appengine

Compass http://www.compass-project.org/ Demo video http://www.kimchy.org/searchable-google-appengine-with-compass/ Information in 2.3.0-beta is. Table of contents 1 use 1.1 Initialization 1.2 demo video, PMF.java imitation because it was initialized with a static initializer. 1.3 Search 1.3.1 If you search for the name Field 1.3.2 When specifying the search Kind 2 Resona How to use Download module http://build.compass-project.org/ of Compass Trunk of select Nightly Build. Results Page built "Artifacts" Click, "Release" to select. Likely to be a list of files, from which to download the compass-2.3.0-beta1.zip. Module Placement Unzip the downloaded module, add the following file CLASSPATH (Google Plugin If you use the "war / WEB-INF / lib" copy, Eclipse projects also add to the Build path.) commons-logging.jar compass-2.3.0-beta1.jar lucene-core.jar Initialization The demonstration video, PMF.java imitation because it was initialized with a static initializer. Some PMF.java private static final Compass compass;   private static final CompassGps compassGps;   static (   compass = new CompassConfiguration ()       . SetConnection ("gae: / / index")       . SetSetting (           CompassEnvironment.ExecutorManager.EXECUTOR_MANAGER_TYPE,           "Disabled"). AddScan (           "Jp.co.topgate.sandbox.compass / model"). BuildCompass ();     compassGps = new SingleCompassGps (getCompass ());   compassGps.addGpsDevice (new Jdo2GpsDevice ("appengine", INSTANCE));   compassGps.start ();   compassGps.index (); )   public static Compass getCompass () (   return compass; )   addScan () does, JDO specifies the name of the Entity package that contains classes. Entity Class Class "@ Searchable" to qualify. Entity can be used as the primary key field "@ SearchableId" to qualify. However, "com.google.appengine.api.datastore.Key" is not bound to accept because, as I have below. @ SearchableId public Long getKeyValue () (     return key.getId (); )   The search field to use as "@ SearchableProperty" to qualify. However, "com.google.appengine.api.datastore.Text" is not bound to accept because, as I have below. @ SearchableProperty public String getContent1String () (     if (content1 == null) (         return "";     )     return content1.getValue (); )   @ SearchableProperty (name = "Field Name") in the class Entity and attribute names can I use different name too. Also, org.apache.lucene.document.Field attributes that can be used when creating. Search Example of getting results @ SuppressWarnings ("serial") public static class SearchResult implements Serializable (   public final String keyValue;   public final String content;   public final String nickname;   public final String email;     public SearchResult (Resource resource) (     this.keyValue = resource.getId ();     this.content = (String) resource.getProperty ("content1String"). getObjectValue ();     this.nickname = (String) resource.getProperty ("nickname"). getObjectValue ();     this.email = (String) resource.getProperty ("email"). getObjectValue ();   ) )   private List <SearchResult> search (String keyWords) (   CompassSearchSession search = PMF.getCompass (). OpenSearchSession ();   CompassHits hits = search.find (keyWords);   int length = hits.length ();   List <SearchResult> result = new ArrayList <SearchResult> (length);   for (int i = 0; i <length; i + +) (     Resource resource = hits.resource (i);     result.add (new SearchResult (resource));   )   return result; )   If you want to search for the name Field Name your search field: Search If you specify a search for Kind Search criteria alias: Kind Name (Class.getSimpleName ()) Resona When you save through JDO, @ SearchableProperty were added using the getter and Field Index to create value, it seems to work. Entity class, using annotations to Index If you do add to the information (that is what I wrote on this page), there always needs to be saved through JDO. LowLevelAPI saved and does not create Entity Index for the (natural or ....) Unowned other Entity relationship holds a reference to its value after the Index can also fetch for it created. , But always return the value of persistence when the getter must return a value, so actually, the "fetch the referenced Entity before saving to keep you" need. unowned @ Persistence private Key otherEntityKey;   @ NotPersistence private OtherEntity otherEntity;   @ SearchablePropperty (name = "otherEntity") public Sting getOtherEntityValue () (   return otherEntity! = null? otherEntity.getValue (): ""; ) Entity Index for the creation, no one could get for a separate? Once implemented the Task Queue Java platform, Index will be delayed for creating Entity can only be good ... and behavior. Compass TaskQueue side and I may well be expected to support. Want control over the creation of the Index Without CompassGps, Compass.Getsearchengineindexmanager() call control. Because some of the lucene subinterface for the smaller may be able to use it? Entity is a separate index to Compass. Openindexsession ()  calls to control  create dynamic query Compass.queryBuilder () Get the querybuilder. 良Shinani later. between, eq, ge, gt, le, le, and, or, like, wildcard and one with an array.   CompassMultiPropertyQueryStringBuilder  or search over multiple properties at once CompassSearchSession.find (queryString) internally CompassSearchSession.queryBuilder (). QueryString (queryString). ToQuery (). Hits () have.   Add to sort search Compassquery  . Addsort ( String  propertyName,  Compassquery.sortdirection  direction) and the like. limit, offset to add I looked, was not sure. CompassHits  to detach (int from, int size) so that, if this 1-2 times will reduce Data itself. I do not mean much. Highlight the text you wish to search results Search engines highlight text in general are presented as fragments around search terms that best match (for example, place a few hundred characters) lucene is called in other bestFragment. The method to get this fragment CompassHits.highlighter (i). Fragment (propertyName)  To obtain fragments of the highlights     CompassSearchSession searchSession = getCompass (). OpenSearchSession ();     CompassHits hits = searchSession.find (text);     int length = hits.getLength ();     if (length> 0) (      for (int i = 0; i <length; i + +) (       / / Here are widespread PR highlights the string.        String fragment = hits.highlighter (i). Fragment ("pr");       Resource resource = hits.resource (i);      )     )     return results;  Wicket to display in IData highlighter in one form or another will take to get the fragment.