Various operations of MongoDB in Java

A. Common query:

1. Query a data: (more used to determine whether the DB has the current data, here is exactly match, fuzzy match using regex ...)

 Public pageurl getbyurl (String url) {        return findOne (new Query (criteria.where ("url"). Is (URL )), Pageurl. class );    }

2. Query multiple data: Linkurl.id belongs to the hierarchical query

 Public List<pageurl> getpageurlsbyurl (intint  end,string linkurlid) {                new Query ();        Query.addcriteria (Criteria.where ("Linkurl.id"). Is (Linkurlid));         return Find (Query.limit (end-begin). Skip (Begin), Pageurl.  Class);            }

3. Fuzzy query:

 Public LongGetprocesslandlogscount (list<condition>conditions) {Query Query=NewQuery (); if(Conditions! =NULL&& conditions.size () > 0) {             for(Condition condition:conditions) {Query.addcriteria (Criteria.where (Condition.getkey ()). Regex (". *?\\ "+condition.getvalue (). toString () +". * ");
            }        }        returnCount (query, Processlandlog.class); }

4. GTE: Greater than or equal to, LTE less than equals ... Note that the type of each field is consistent with the data type in MongoDB when querying

 PublicList<processlandlog> Getprocesslandlogs (intBeginintEnd,list<condition>conditions,string orderfield,direction Direction) {Query Query=NewQuery (); if(Conditions! =NULL&& conditions.size () > 0) {             for(Condition condition:conditions) {if(Condition.getkey (). Equals ("Time") {Query.addcriteria (Criteria.where ("Time"). GTE (Condition.getvalue ()));//GTE: Greater than or equal to}Else if(Condition.getkey (). Equals ("Inserttime") {Query.addcriteria (Criteria.where ("Inserttime"). GTE (Condition.getvalue ())); }Else{Query.addcriteria (Criteria.where (Condition.getkey ()). is (Condition.getvalue () ));                }            }        }        returnFind (Query.limit (end-begin). Skip (Begin). with (NewSort (NewSort.order (direction, OrderField)), Processlandlog.class); }

Public list<dpsland> getdpslandsbytime (int begin, int end, Date begindate,date endDate) {
Return Find (New Query (Criteria.where ("UpdateTime"). GTE (Begindate). LTE (EndDate)). Limit (End-begin). Skip (Begin),
Dpsland.class);
}

5. Number of queries:

 Public long getpageinfoscount (list<condition> conditions) {        new  Query ();         if null && conditions.size () > 0) {            for  (Condition Condition: Conditions) {
                Query.addcriteria (Criteria.where (Condition.getkey ()). is (Condition.getvalue ()));            }        }         return count (query, PageInfo.  Class);    }

6. Update a field for one data:

Public Writeresult UpdateTime (pageurl pageurl) {        String id = Pageurl.getid ();        return Updatefirst (new Query (Criteria.where ("id")), Update.update ("UpdateTime", Pageurl.getupdatetime ()), Pageurl. class);}     

7. Update multiple fields of one data:

//Call UpdatePrivatevoidUpdateprocesslandlog (Processlandlog Processlandlog,IntCrawlresult) {list<string> fields =New arraylist<string>(); list<object> values =New arraylist<object>(); Fields.Add ("state"); Fields.Add ("Result"); Fields.Add ("Time"); Values.add ("1"); Values.add (Crawlresult); Values.add (Calendar.getinstance (). GetTime ()); Processlandlogreposity.updateprocesslandlog (Processlandlog, fields, values); }// update public void Updateprocesslandlog (Processlandlog land, list<string> fields,list<object> new update (); int size = Fields.size (); for (int i = 0; i < size; I++ Fields.get (i); Object value = Values.get (i); Update.set (field, value);} updatefirst (new Query (criteria.where ("id"). is (Land.getid ())), Update,processlandlog. class       

8. Delete data:

 Public void DeleteObject (class<t> clazz,string ID) {        remove (new Query (Criteria.where ( "id"). is (ID)), clazz);    }

9. Save the data:

Insert a piece of data
publicvoid  saveobject (Object obj) {        insert (obj);    }
Insert multiple Data     public void saveobjects (list<t> objects) {        for  (t t:objects) {            insert (t);        }    }