MongoDB3.0+数据操作工具封装

该文章只适合于初学者，里面的代码很简单，也多需要优化完善的地方，就是为了让初学者少走弯路，起到借鉴的作用。

需要引用的包：

<span style="white-space:pre">		</span><dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>4.8.1</version>
<scope>test</scope>
</dependency>
<dependency>
<groupId>org.jmock</groupId>
<artifactId>jmock-junit4</artifactId>
<version>2.8.1</version>
</dependency>
<dependency>
<groupId>org.jmock</groupId>
<artifactId>jmock</artifactId>
<version>2.8.1</version>
</dependency>
<dependency>
<groupId>org.jmock</groupId>
<artifactId>jmock-legacy</artifactId>
<version>2.8.1</version>
</dependency>
<dependency>
<groupId>org.mongodb</groupId>
<artifactId>mongo-java-driver</artifactId>
<version>3.1.0</version>
</dependency>

首先，我们拿一个用户来进行操作：

1创建一个User实体对象：

public class User {
private String name = null;

private int age = -1;

private int updateTimes = -1;

public String getName()
{
return name;
}

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

public int getAge()
{
return age;
}

public void setAge(int age)
{
this.age = age;
}

public int getUpdateTimes()
{
return updateTimes;
}

public void setUpdateTimes(int updateTimes)
{
this.updateTimes = updateTimes;
}

@Override
public String toString()
{
return "User [name=" + name + ", age=" + age + ", updateTimes=" + updateTimes + "]";
}

public Document toBasicDBObject()
{
Document user = new Document();
user.put("name", this.name);
user.put("age", this.age);
user.put("updateTimes", this.updateTimes);
return user;
}
}

2接着，创建一个工具类，让来连接MongoDB数据库：

public final class MongoDBUtil
{
private static MongoClient mongoClient = null;
private static MongoDatabase database = null;
private static ServerAddress serverAddress = null;
private static MongoCredential  credentials  = null;
private static List<ServerAddress> addressLists =new ArrayList<ServerAddress>();
private static List<MongoCredential> credentialsLists = new ArrayList<MongoCredential>();

public static void init(){
try{
//mongoClient = new MongoClient("192.168.32.129",27017);
serverAddress = new ServerAddress("192.168.32.129",27017);
addressLists.add(serverAddress);
//credentials = MongoCredential.createCredential("test1", "test", "test1".toCharArray());
credentials = MongoCredential.createMongoCRCredential("test1", "test", "test1".toCharArray());
credentialsLists.add(credentials);
mongoClient = new MongoClient(addressLists, credentialsLists);
}catch (MongoException e)
{
System.out.println(e.toString());
}
if(null != mongoClient){
database = mongoClient.getDatabase("test");
}

}
public static MongoClient getMongoClient()
{
if (null == mongoClient)
{
init();
}

return mongoClient;
}
/**
* 获取database
* @return
*/
public static MongoDatabase getDatabase() {
if(null == mongoClient){
init();
}
return database;
}
/**
* 获取User Collection
* @return
*/
public static MongoCollection<Document> getUserCollection(){
if(null == database){
database = getDatabase();
}
if(null != database){
return database.getCollection("data");
}
return null;
}
/**
* 删除所有用户
*/
public static void deleteAllUsers(){
System.out.println("删除User Collection中所有数据...");
MongoCollection<Document> collection = getUserCollection();

FindIterable<Document> cursor = collection.find();
while(cursor.iterator().hasNext()){
collection.deleteOne(cursor.iterator().next());
}
System.out.println("====================================");
}
/**
* 查询所有用户
*/
public static void queryAllUsers(){
System.out.println("查询User Collection中所有数据：");

MongoCollection<Document> collection = getUserCollection();

//方法一
/*MongoCursor<Document> cur = collection.find().iterator();
try{
while (cur.hasNext())
{
System.out.println(cur.next().toJson());
}
}catch(Exception e){
System.out.println(e.getMessage()+e);
}finally {
cur.close();
}*/
//方法二
for (Document  cursor : collection.find()) {
System.out.println(cursor.toJson());
}

System.out.println("================================================================");
}

/**
* 保存用户信息
* @param user
*/
public static void saveUser(User user){
System.out.println("保存用户信息：" + user.toString());
MongoCollection<Document> userCollection = getUserCollection();
userCollection.insertOne(user.toBasicDBObject());
System.out.println("================================================================");

}

/**
* 更新用户信息
* @param user
*/
public static void update(User user)
{
System.out.println("更新用户信息：" + user.toString());
MongoCollection<Document> userCollection = getUserCollection();
userCollection.updateMany(new Document().append("name", user.getName()), user.toBasicDBObject());
System.out.println("================================================================");
}

/**
* 增加用户更新次数
* @param userName 用户名
*/
public static void incUserUpdateTimes(String userName)
{
MongoCollection<Document> userCollection = getUserCollection();
BasicDBObject newDocument =new BasicDBObject().append("$inc", new BasicDBObject().append("updateTimes", 1));
userCollection.updateOne(new BasicDBObject().append("name", userName), newDocument);
}

/**
* 更新用户名
* @param oldName 旧用户名
* @param newName 新用户名
*/
public static void updateUserName(String oldName, String newName)
{
MongoCollection<Document> userCollection = getUserCollection();
BasicDBObject newDocument =new BasicDBObject().append("$set", new BasicDBObject().append("name", newName));
userCollection.updateOne(new BasicDBObject().append("name", oldName), newDocument);
}

/**
* 更新User Age
* @param userName 用户名
* @param age Age
*/
public static void updateUserAge(String userName, int age)
{
MongoCollection<Document> userCollection = getUserCollection();
BasicDBObject newDocument =new BasicDBObject().append("$set", new BasicDBObject().append("age", age));
userCollection.updateOne(new BasicDBObject().append("name", userName), newDocument);
}

public static User queryUserByName(String userName)
{
MongoCollection<Document> userCollection = getUserCollection();
BasicDBObject query =new BasicDBObject();
query.put("name", userName);
User user = null;
for (Document  cursor : userCollection.find(query)) {
System.out.println(cursor.toJson());
Map<String, Object> userMap = (Map<String, Object>) cursor;

user = new User();
user.setName(String.valueOf(userMap.get("name")));
user.setAge(Integer.valueOf(String.valueOf(userMap.get("age"))));
user.setUpdateTimes(Integer.valueOf(String.valueOf(userMap.get("updateTimes"))));

System.out.println(user.toString());
}
/*MongoCursor<Document> cursor = userCollection.find(query).iterator();
while(cursor.hasNext())
{
Document document = cursor.next();

Map<String, Object> userMap = (Map<String, Object>) document;

user = new User();
user.setName(String.valueOf(userMap.get("name")));
user.setAge(Integer.valueOf(String.valueOf(userMap.get("age"))));
user.setUpdateTimes(Integer.valueOf(String.valueOf(userMap.get("updateTimes"))));

System.out.println(user.toString());
}*/

return user;
}

public static void queryUserByAge(List<Integer> ageList)
{
MongoCollection<Document> userCollection = getUserCollection();
BasicDBObject query =new BasicDBObject();
query.put("age", new BasicDBObject("$in", ageList));
FindIterable<Document> cursor = userCollection.find(query);
while(cursor.iterator().hasNext())
{
System.out.println(cursor.iterator().next());
}
}

public static void queryUserByGreatThanAge(int age)
{
MongoCollection<Document> userCollection = getUserCollection();
BasicDBObject query =new BasicDBObject();
query.put("age", new BasicDBObject("$gt", age));
FindIterable<Document> cursor = userCollection.find(query);
while(cursor.iterator().hasNext())
{
System.out.println(cursor.iterator().next());
}
}

public static void queryUserByLessThanAge(int age)
{
MongoCollection<Document> userCollection = getUserCollection();
BasicDBObject query =new BasicDBObject();
query.put("age", new BasicDBObject("$lt", age));
FindIterable<Document> cursor = userCollection.find(query);
while(cursor.iterator().hasNext())
{
System.out.println(cursor.iterator().next());
}
}

public static void queryUserNotEquireAge(int age)
{
MongoCollection<Document> userCollection = getUserCollection();
BasicDBObject query =new BasicDBObject();
query.put("age", new BasicDBObject("$ne", age));
FindIterable<Document> cursor = userCollection.find(query);
while(cursor.iterator().hasNext())
{
System.out.println(cursor.iterator().next());
}
}

public static void deleteUserByName(String userName)
{
MongoCollection<Document> userCollection = getUserCollection();
BasicDBObject document =new BasicDBObject();
document.put("name", userName);
userCollection.deleteMany(document);
}

public static void deleteUserByNameList(List<String> nameList)
{
MongoCollection<Document> userCollection = getUserCollection();
BasicDBObject query =new BasicDBObject();
query.put("name", new BasicDBObject("$in", nameList));
userCollection.deleteMany(query);
}

public static void setDatabase(MongoDatabase database) {
MongoDBUtil.database = database;
}

}

注意：该工具中只有下面单元测试中的几个方法是成功测试的，其他的还需要自己下面测试，应该也是没问题的。

3最后，单元测试看看效果，是否真的可行：

public class MongoDBTest
{
public static void main(String[] args) {
System.out.println("================================================================");
// 查询所有的Database
MongoClient mongoClient = MongoDBUtil.getMongoClient();
System.out.println("查询MongoDB中存在的所有数据库：");
for (ServerAddress name : mongoClient.getAllAddress()) {
System.out.println("dbName: " + name);
}
// 查询DB中所有的Collection（可以理解为像关系型数据库中的Table）
MongoDatabase database = MongoDBUtil.getDatabase();
System.out.println("abd="+database.getCollection("abc").toString());
MongoCollection<Document> collection = null;
List<Document> foundDocument = null;
collection = database.getCollection("person");
foundDocument = collection.find().into(
new ArrayList<Document>());
System.out.println(foundDocument);
}

@Test
public void addUsers(){
for(int i=0;i<20000;i++){
User user = new User();
user.setName("user" + i);
user.setAge(2);
user.setUpdateTimes(0);
//保存用户信息
MongoDBUtil.saveUser(user);
System.out.println("------------"+i);
}
}

@Test
public void deleteAllUsers(){
MongoDBUtil.deleteAllUsers();
}

@Test
public void queryAllUsers(){
MongoDBUtil.queryAllUsers();
}

@Test
public void updateUser(){
User user = new User();
user.setName("user19999");
user.setAge(39);
user.setUpdateTimes(3);
MongoDBUtil.update(user);
}

@Test
public void queryUserByName(){
MongoDBUtil.queryUserByName("user19999");
}
}

这里，就完了，希望不要吐槽

。