java 操作MongoDB

需要的jar包和安装包：https://pan.baidu.com/s/1P6ZxuWFtKrTU7eRRV9OkAg 密码: kf76
我用Robo 3T 1.1.1作为MongoDB的GUI界面，有需要可以用，用cmd控制台也行。
看看Robo 3T界面



失效给dh2531@foxmail.com发送邮件。
代码需要一定的java基础，泛型he
1.entity实体类
package entity;

public class Emp {

private int id;
private String name;

public int getId() {
return id;
}

public void setId(int id) {
this.id = id;
}

public String getName() {
return name;
}

public void setName(String name) {
this.name = name;
}

@Override
public String toString() {
return "Emp{" + "id=" + id + ", name='" + name + '\'' + '}';
}
}
2.util 类（MongoDBUtil1封装MongoDB操作,Bean2DBObject转换对象）

package util;

import com.mongodb.*;

import java.beans.BeanInfo;
import java.beans.Introspector;
import java.beans.PropertyDescriptor;
import java.io.IOException;
import java.io.InputStream;
import java.lang.reflect.Method;
import java.util.ArrayList;
import java.util.Date;
import java.util.List;
import java.util.Properties;

public class MongoDBUtil1 {

private static Mongo mongo = null;
private MongoDBUtil1(){
super();
}

private static String host;
private static int port;
private static String dbName;

static {
InputStream in = null;
Properties prop = new Properties();
try{
if(in==null) in = MongoDBUtil1.class.getResourceAsStream("../MongoDB.properties");
prop.load(in);
host = prop.getProperty("host");
port = Integer.parseInt(prop.getProperty("port"));
dbName = prop.getProperty("dbName");
}catch (IOException e){
System.out.println("读配置文件出错");
e.printStackTrace();
}finally {
System.out.println("读配置文件end");
}

}

public static void insert(Object obj,String table){
if (mongo==null) mongo = new Mongo(host,port);
try{
DB db = mongo.getDB(dbName);
DBCollection dbCollection = db.getCollection(table);
if (dbCollection==null) {
DBObject dbObj = new BasicDBObject();
dbCollection = db.createCollection(table,dbObj);
}
dbCollection.insert(Bean2DBObject.bean2DBObject(obj));
}catch (Exception e){
System.out.println([b]"插入出错");
}finally {
if (mongo!=null) mongo.close();
}
}

public static List find(Object obj,String table,String field) {
if (mongo==null) mongo = new Mongo(host,port);
try{
DB db = mongo.getDB(dbName);
DBCollection dbCollection = db.getCollection(table);
if (dbCollection==null) {
DBObject dbObj = new BasicDBObject();
dbCollection = db.createCollection(table,dbObj);
}
BasicDBObject searchQuery = new BasicDBObject();
Object fieldValue=null;

Class clazz=obj.getClass();
BeanInfo beanInfo= Introspector.getBeanInfo(clazz);
PropertyDescriptor[] pds=beanInfo.getPropertyDescriptors();
for(PropertyDescriptor pd:pds){
if(pd.getName().equals(field)){
System.out.println(field+":"+pd.getReadMethod());
Method getter=pd.getReadMethod();
if (!getter.isAccessible()) getter.setAccessible(true);
fieldValue = getter.invoke(obj);
}
}

if (fieldValue==null) {
return null;
} else if (fieldValue instanceof Integer) {
// 判断变量的类型
int value = ((Integer) fieldValue).intValue();
searchQuery.put(field, value);
} else if (fieldValue instanceof String) {
String value = (String) fieldValue;
searchQuery.put(field, value);
} else if (fieldValue instanceof Double) {
double value = ((Double) fieldValue).doubleValue();
searchQuery.put(field, value);
} else if (fieldValue instanceof Float) {
float value = ((Float) fieldValue).floatValue();
searchQuery.put(field, value);
} else if (fieldValue instanceof Long) {
long value = ((Long) fieldValue).longValue();
searchQuery.put(field, value);
} else if (fieldValue instanceof Boolean) {
boolean value = ((Boolean) fieldValue).booleanValue();
searchQuery.put(field, value);
} else if (fieldValue instanceof Date) {
Date value = (Date) fieldValue;
searchQuery.put(field, value);
}
DBCursor cur = dbCollection.find(searchQuery);
List<Object> results = new ArrayList<Object>();
while (cur.hasNext()){
results.add(cur.next());
}
return results;
}catch(Exception e){
e.printStackTrace();
}finally {
if (mongo!=null) mongo.close();
}
return null;
}

}

package util;

import com.mongodb.BasicDBObject;
import com.mongodb.DBObject;

import java.lang.reflect.Field;
import java.util.Date;

public class Bean2DBObject {

/**
* 将实体Bean对象转换为DBObject
*/
public static <T> DBObject bean2DBObject(T bean) throws IllegalAccessException {
if(bean == null) return null;
DBObject dbObject = new BasicDBObject();
//获得对象类的属性域
Field[] fields = bean.getClass().getDeclaredFields();
for(Field field:fields){
//获得变量属性名
String varName = field.getName();
if(!field.isAccessible())field.setAccessible(true);
Object param = field.get(bean);
//System.out.println(param);
if (param==null){
continue;
}else if (param instanceof Integer) {
// 判断变量的类型
int value = ((Integer) param).intValue();
dbObject.put(varName, value);
} else if (param instanceof String) {
String value = (String) param;
dbObject.put(varName, value);
} else if (param instanceof Double) {
double value = ((Double) param).doubleValue();
dbObject.put(varName, value);
} else if (param instanceof Float) {
float value = ((Float) param).floatValue();
dbObject.put(varName, value);
} else if (param instanceof Long) {
long value = ((Long) param).longValue();
dbObject.put(varName, value);
} else if (param instanceof Boolean) {
boolean value = ((Boolean) param).booleanValue();
dbObject.put(varName, value);
} else if (param instanceof Date) {
Date value = (Date) param;
dbObject.put(varName, value);
}
}
return dbObject;
}
}

package util;

import com.mongodb.BasicDBObject;
import com.mongodb.DBObject;

import java.lang.reflect.Field;
import java.util.Date;

public class Bean2DBObject {

/**
* 将实体Bean对象转换为DBObject
*/
public static <T> DBObject bean2DBObject(T bean) throws IllegalAccessException {
if(bean == null) return null;
DBObject dbObject = new BasicDBObject();
//获得对象类的属性域
Field[] fields = bean.getClass().getDeclaredFields();
for(Field field:fields){
//获得变量属性名
String varName = field.getName();
if(!field.isAccessible())field.setAccessible(true);
Object param = field.get(bean);
//System.out.println(param);
if (param==null){
continue;
}else if (param instanceof Integer) {
// 判断变量的类型
int value = ((Integer) param).intValue();
dbObject.put(varName, value);
} else if (param instanceof String) {
String value = (String) param;
dbObject.put(varName, value);
} else if (param instanceof Double) {
double value = ((Double) param).doubleValue();
dbObject.put(varName, value);
} else if (param instanceof Float) {
float value = ((Float) param).floatValue();
dbObject.put(varName, value);
} else if (param instanceof Long) {
long value = ((Long) param).longValue();
dbObject.put(varName, value);
} else if (param instanceof Boolean) {
boolean value = ((Boolean) param).booleanValue();
dbObject.put(varName, value);
} else if (param instanceof Date) {
Date value = (Date) param;
dbObject.put(varName, value);
}
}
return dbObject;
}
}

3.dao类
import entity.Emp;

import java.util.List;

public interface EmpDao {

public void insert(Emp e);
public List find(Emp e);
public void update(Emp e);
public void delete(Emp e);
}4.daoImpl实现类
package daoImp
b5b6
l;

import dao.EmpDao;
import entity.Emp;
import util.MongoDBUtil1;

import java.util.List;

public class EmpDaoImpl implements EmpDao {

@Override
public void insert(Emp e) {
MongoDBUtil1.insert(e,"emp");
System.out.println("插入完毕");
}

@Override
public List find(Emp e) {
List<Emp> list = MongoDBUtil1.find(e,"emp","id");
return list;
}

@Override
public void update(Emp e) {

}

@Override
public void delete(Emp e) {

}
}5.resources资源（MongoDB.properties）
host=localhost
port=27017
dbName=ChatRoom6.测试类
package test;

import dao.EmpDao;
import daoImpl.EmpDaoImpl;
import entity.Emp;
import org.junit.Test;

public class TestDB1 {

@Test
public void test1() {
Emp emp = new Emp();
emp.setId(1);
emp.setName("donghui");
EmpDao dao = new EmpDaoImpl();
dao.insert(emp);
}

@Test
public void test2() {
Emp emp = new Emp();
emp.setId(1);
emp.setName("donghui");
EmpDao dao = new EmpDaoImpl();
System.out.println(dao.find(emp));
}
}