本文实例为大家分享了Java操作MongoDB模糊查询和分页查询，供大家参考，具体内容如下
模糊查询条件：
1、完全匹配
Pattern pattern = Pattern.compile("^name$", Pattern.CASE_INSENSITIVE);
2、右匹配
Pattern pattern = Pattern.compile("^.*name$", Pattern.CASE_INSENSITIVE);
3、左匹配
Pattern pattern = Pattern.compile("^name.*$", Pattern.CASE_INSENSITIVE);
4、模糊匹配
Pattern pattern = Pattern.compile("^.*name8.*$", Pattern.CASE_INSENSITIVE);
记录总数查询：
count()，返回查询总数。
查询记录排序：
BasicDBObject sort = new BasicDBObject();
sort.put("name",1);
1、表示正序；－1.表示倒序
分页查询：
skip()，跳过多少条记录
limit()，返回多少条记录
代码实例:
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package com.what21.mongodb.demo;
import java.util.ArrayList;
import java.util.List;
import java.util.Set;
import java.util.regex.Pattern;
import com.mongodb.BasicDBObject;
import com.mongodb.DB;
import com.mongodb.DBCollection;
import com.mongodb.DBCursor;
import com.mongodb.DBObject;
import com.mongodb.MongoClient;
import com.mongodb.MongoClientOptions;
import com.mongodb.MongoCredential;
import com.mongodb.ServerAddress;
public class OperateDemo2 {
/**
* @return
* @throws Exception
*/
public static MongoClient getMongoClient()throws Exception{
try {
//===================================================//
List<ServerAddress> serverList = new ArrayList<ServerAddress>();
serverList.add(new ServerAddress("192.168.18.85", 27017));
//===================================================//
List<MongoCredential> mcList = new ArrayList<MongoCredential>();
String username = "root";
String database = "demo";
char[] password = "root123".toCharArray();
mcList.add(MongoCredential.createCredential(username, database,password));
//===================================================//
MongoClientOptions.Builder builder = MongoClientOptions.builder();
// 与目标数据库能够建立的最大connection数量为50
builder.connectionsPerHost(50);
// 如果当前所有的connection都在使用中，则每个connection上可以有50个线程排队等待
builder.threadsAllowedToBlockForConnectionMultiplier(50);
// 一个线程访问数据库的时候，在成功获取到一个可用数据库连接之前的最长等待时间为2分钟
// 这里比较危险，如果超过maxWaitTime都没有获取到这个连接的话，该线程就会抛出Exception
// 故这里设置的maxWaitTime应该足够大，以免由于排队线程过多造成的数据库访问失败
builder.maxWaitTime(1000*60*2);
// 与数据库建立连接的timeout设置为1分钟
builder.connectTimeout(1000*60*1);
//===================================================//
MongoClientOptions mco = builder.build();
return new MongoClient(serverList, mcList, mco);
} catch (Exception e) {
throw e;
}
}
/**
* @param dbname
* @return
* @throws Exception
*/
public static DB getDB(String dbname) throws Exception{
return getMongoClient().getDB(dbname);
}
/**
* @param db
*/
public static void collections(DB db){
Set<String> colls = db.getCollectionNames();
for (String collName : colls) {
System.out.println(collName);
}
}
/**
* 记录总数查询
*
* @param db
* @param name
*/
public static void count(DB db,String name){
DBCollection dbColl = db.getCollection(name);
int count = dbColl.find().count();
System.out.println("共有： " + count + "个");
}
/**
* 模糊查询
*
* @param db
* @param name
*/
public static void query(DB db,String name){
DBCollection dbColl = db.getCollection(name);
//完全匹配
//Pattern pattern = Pattern.compile("^name$", Pattern.CASE_INSENSITIVE);
//右匹配
//Pattern pattern = Pattern.compile("^.*name$", Pattern.CASE_INSENSITIVE);
//左匹配
//Pattern pattern = Pattern.compile("^name.*$", Pattern.CASE_INSENSITIVE);
//模糊匹配
Pattern pattern = Pattern.compile("^.*name8.*$", Pattern.CASE_INSENSITIVE);
BasicDBObject query = new BasicDBObject();
query.put("name",pattern);
BasicDBObject sort = new BasicDBObject();
// 1,表示正序； －1,表示倒序
sort.put("name",1);
DBCursor cur = dbColl.find(query).sort(sort);
int count = 0;
while (cur.hasNext()) {
DBObject obj = cur.next();
System.out.print("name=" + obj.get("name"));
System.out.print(",email=" + obj.get("email"));
System.out.println(",passwd=" + obj.get("passwd"));
count ++;
}
System.out.println("共有： " + count + "个");
}
/**
* 分页查询
*
* @param db
* @param name
* @param start
* @param pageSize
*/
public static void page(DB db,String name,int start,int pageSize){
DBCollection dbColl = db.getCollection(name);
BasicDBObject sort = new BasicDBObject();
sort.put("name",1);
DBCursor cur = dbColl.find().sort(sort).skip(start).limit(pageSize);;
int count = 0;
while (cur.hasNext()) {
DBObject obj = cur.next();
System.out.print("name=" + obj.get("name"));
System.out.print(",email=" + obj.get("email"));
System.out.println(",passwd=" + obj.get("passwd"));
count ++;
}
System.out.println("共有： " + count + "个");
}
/**
* @param args
* @throws Exception
*/
public static void main(String[] args) throws Exception {
DB db = getDB("demo");
collections(db);
String name = "users";
System.out.println("count()=================================================");
count(db,name);
System.out.println("query()=================================================");
query(db,name);
System.out.println("page()=================================================");
page(db,name,10, 10);
}
}
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以上就是Java操作MongoDB模糊查询和分页查询的实现代码，希望对大家的学习有所帮助。