上两篇文章:
介绍到了在MongoDB的控制台完成MongoDB的数据操作、以及通过Java MongoDB 的驱动完成在Java中对MongoDB的操作，通过前两篇文章我们对MongoDB有了全面、深刻的认识和理解。现在我们就看看利用Morphia库来操作MongoDB。
开发环境：
System：Windows
IDE：eclipse、MyEclipse 8
Database：mongoDB
开发依赖库：
JavaEE5、mongo-2.5.3.jar、junit-4.8.2.jar
Email：hoojo_@126.com
Blog：
一、准备工作
1、 首先，下载mongoDB对Java支持的驱动包
驱动包下载地址：https://github.com/mongodb/mongo-java-driver/downloads
mongoDB对Java的相关支持、技术：http://www.mongodb.org/display/DOCS/Java+Language+Center
驱动源码下载：https://download.github.com/mongodb-mongo-java-driver-r2.6.1-7-g6037357.zip
在线查看源码：https://github.com/mongodb/mongo-java-driver
Morphia jar包下载：http://code.google.com/p/morphia/downloads/list
2、 下面建立一个JavaProject工程，导入下载下来的驱动包。即可在Java中使用Morphia，目录如下：
二、Java操作MongoDB示例
在本示例之前你需要启动mongod.exe的服务，在你安装mongoDB的目录中，找到mongod.exe启动服务后，下面的程序才能顺利执行；
1、 Java操作mongoDB数据库，操作索引
Mongo mongo = new Mongo();
这样就创建了一个MongoDB的数据库连接对象，它默认连接到当前机器的localhost地址，端口是27017。
DB db = mongo.getDB(“test”);
这样就获得了一个test的数据库，如果mongoDB中没有创建这个数据库也是可以正常运行的。如果你读过上一篇文章就知道，mongoDB可以在没有创建这个数据库的情况下，完成数据的添加操作。当添加的时候，没有这个库，mongoDB会自动创建当前数据库。
得到了db，下一步我们要获取一个“聚集集合DBCollection”，通过db对象的getCollection方法来完成。
DBCollection users = db.getCollection("users");
这样就获得了一个DBCollection，它相当于我们数据库的“表”。
查询所有数据
DBCursor cur = users.find();
while (cur.hasNext()) {
System.out.println(cur.next());
}用BasicDBObjectBuilder，向users对象中添加数据
user = BasicDBObjectBuilder.start("id", 1546555)
.append("name", "jojo").add("address", "gz")
.append("email", "hoojo_@126.com")
.get();
插入数据
users.insert(user);
可以利用JSON工具来序列化对象数据
JSON.serialize(cur)
完整源码
package com.hoo.test;
import java.net.UnknownHostException;import com.hoo.entity.User;import com.hoo.util.BasicDBObjectUtils;import com.mongodb.BasicDBObjectBuilder;import com.mongodb.DB;import com.mongodb.DBCollection;import com.mongodb.DBCursor;import com.mongodb.DBObject;import com.mongodb.Mongo;import com.mongodb.MongoException;import com.mongodb.util.JSON;
/*** <b>function:</b> Mongo实例对象的相关方法测试* @author hoojo* @createDate 2011-5-24 下午02:42:29* @file MongoDBTest.java* @package com.hoo.test* @project MongoDB* @blog* @email hoojo_@126.com* @version 1.0*/public class MongoDBTest {
public static void main(String[] args) throws UnknownHostException, MongoException {Mongo mg = new Mongo();
System.out.println("查询所有的Database的名称");for (String name : mg.getDatabaseNames()) {System.out.println("dbName: " + name);
}
System.out.println("查询test库中的所有collection集合（表）名称");DB db = mg.getDB("test");for (String name : db.getCollectionNames()) {System.out.println("collectionName: " + name);
}
System.out.println("添加测试数据");DBCollection users = db.getCollection("users");try {// 用自定义BasicDBObjectUtils工具类，将User Enity对象转换成DBObjectDBObject user = BasicDBObjectUtils.castModel2DBObject(new User("345567", "jack", 22, "beijin"));
users.insert(user);
// 用BasicDBObjectBuilder构建一个DBObject对象user = BasicDBObjectBuilder.start("id", 1546555).append("name", "jojo").add("address", "gz").append("email", "hoojo_@126.com").get();
users.insert(user);
} catch (Exception e) {
e.printStackTrace();
}
System.out.println("游标查询所有users集合数据");
DBCursor cur = users.find();
while (cur.hasNext()) {
System.out.println(cur.next());
}
System.out.println("查询游标相关内容");
System.out.println(cur.count());
System.out.println(cur.getCursorId());
System.out.println(cur.getOptions());
System.out.println(cur.getQuery());
System.out.println(cur.getSizes().listIterator());
System.out.println(cur.itcount());
//System.out.println(cur.length());
System.out.println(cur.size());
System.out.println(cur.numGetMores());
System.out.println(cur.curr());
//System.out.println(cur.toArray().get(0));
System.out.println("显示游标查询到的所有内容： " + JSON.serialize(cur));
}
}
工具类，将带有getter、setter方法的Java类序列化成DBObject对象
package com.hoo.util;
import java.lang.reflect.Method;import com.mongodb.BasicDBObject;import com.mongodb.DBObject;
/*** <b>function:</b> 将Entity/Model转换成DBObject* @author hoojo* @createDate 2011-5-30下午01:53:08* @file BasicDBObjectUtil.java* @package com.hoo.util* @project MongoDB* @blog* @email hoojo_@126.com* @version 1.0*/
publicclass BasicDBObjectUtils {
public static<T> DBObject castModel2DBObject(T entity) throws Exception {
Method[] method = entity.getClass().getMethods();
DBObject dbObject = new BasicDBObject();for (Method m : method) {//System.out.println(m.getName());if (m.getName().startsWith("get")) {String name = m.getName().replace("get", "");for (Method m2 : method) {if (m2.getName().equals("set" + name)) {
name = name.substring(0, 1).toLowerCase() + name.substring(1);
Object returnVal = m.invoke(entity, new Object[] {});if (returnVal != null) {//System.out.println(name + " : " + m.invoke(shipping, new Object[] {}));
dbObject.put(name, returnVal);
}
}
}
}
}
System.out.println("dbObject: " + dbObject);return dbObject;
}
}
2、 完成索引操作，首先建立一个MongoDB4IndexTest.java，基本测试代码如下：
package com.hoo.test;
import java.net.UnknownHostException;import java.util.ArrayList;import java.util.List;import org.bson.types.ObjectId;import org.junit.After;import org.junit.Before;import org.junit.Test;import com.mongodb.BasicDBObject;import com.mongodb.Bytes;import com.mongodb.DB;import com.mongodb.DBCollection;import com.mongodb.DBCursor;import com.mongodb.DBObject;import com.mongodb.Mongo;import com.mongodb.MongoException;import com.mongodb.QueryOperators;import com.mongodb.util.JSON;
/*** <b>function:</b> 实现MongoDB的Index操作* @author hoojo* @createDate 2011-6-2 下午03:21:23* @file MongoDB4IndexTest.java* @package com.hoo.test* @project MongoDB* @blog* @email hoojo_@126.com* @version 1.0*/public class MongoDB4IndexTest {
private Mongo mg = null;private DB db;private DBCollection users;
@Before
public void init() {try {mg = new Mongo();//mg = new Mongo("localhost", 27017);} catch (UnknownHostException e) {
e.printStackTrace();
} catch (MongoException e) {
e.printStackTrace();
}
//获取temp DB；如果默认没有创建，mongodb会自动创建db = mg.getDB("temp");//获取users DBCollection；如果默认没有创建，mongodb会自动创建users = db.getCollection("users");
}
@After
public void destory() {if (mg != null)
mg.close();
mg = null;
db = null;
users = null;
System.gc();
}
public void print(Object o) {
System.out.println(o);
}
}
3、 下面完成对象Collection的index的操作
/*** <b>function:</b> 测试Collection的index相关操作* @author hoojo* @createDate 2012-2-16 下午08:32:26*/
@Test
public void testIndex() {
query();
for (DBObject index : coll.getIndexInfo()) {print("IndexInfo: " + index);
}
coll.dropIndexes();
//创建索引coll.createIndex(new BasicDBObject("name", "idx_name"));print(coll.findOne(new BasicDBObject("name", "haha")));coll.createIndex(coll.findOne(new BasicDBObject("name", "haha")));DBObject o = new BasicDBObject("unique", true);//coll.createIndex(coll.findOne(), o);
// 修改索引，如果存在就修改不存在就添加
coll.ensureIndex(o);
coll.ensureIndex("age_1");coll.ensureIndex(new BasicDBObject("age3_1", 6), new BasicDBObject("ts", -1));coll.ensureIndex(new BasicDBObject("age_2", 1), new BasicDBObject( "ts" , 1 ));coll.ensureIndex(new BasicDBObject("password", 2), new BasicDBObject( "z" , "idx" ));coll.ensureIndex(new BasicDBObject("password", 1), new BasicDBObject( "etc" , "idx" ));// 创建唯一索引coll.ensureIndex(new BasicDBObject("emial", 2), new BasicDBObject("unique", false));// 创建索引，指定索引名称default_indexcoll.ensureIndex(new BasicDBObject("address", 1), new BasicDBObject( "name" , "default_index"));// 创建索引对象，索引名称user_indexcoll.ensureIndex(coll.findOne(new BasicDBObject("name", "hoho")), "user_index");// 唯一索引coll.ensureIndex(coll.findOne(new BasicDBObject("name", "hehe")), "users_index_unique", true);
// 查询所有索引for (DBObject index : coll.getIndexInfo()) {print("IndexInfo: " + index);
}
print(DBCollection.genIndexName(coll.findOne()));
//coll.dropIndex(coll.findOne());print(DBCollection.genIndexName(new BasicDBObject("password", 2)));//coll.dropIndex(DBCollection.genIndexName(new BasicDBObject("password", 2)));//coll.dropIndexes();//coll.dropIndexes("assword_1");
}
三、Morphia基本操作
1、 morphia可以利用annotation对JavaEntity进行注解，那样我们就可以用morphia操作JavaEntity对象
package com.hoo.entity;
import com.google.code.morphia.annotations.Entity;import com.google.code.morphia.annotations.Id;
/*** <b>function:</b> JavaEntity对象* @author hoojo* @createDate 2011-5-31上午11:45:21* @file User.java* @package com.hoo.entity* @project Morphia* @blog* @email hoojo_@126.com* @version 1.0*///利用morphia的annotation进行注解
@Entity
public class User {
@Id
private long id;
private String name;private boolean sex;private int age;private String address;
public User() {
}
public User(long id, String name, boolean sex, int age, String address) {super();this.id = id;this.name = name;this.sex = sex;this.age = age;this.address = address;
}
//getter、setter
@Override
public String toString() {return this.id + "#" + this.name + "#" + this.age + "#" + this.sex + "#" + this.address;
}
}
2、 对Morphia对象一些简单的使用，看看该对象提供了哪些基本的操作方法
package com.hoo.test.morphia;
import java.net.UnknownHostException;import org.junit.After;import org.junit.Before;import org.junit.Test;import com.google.code.morphia.Datastore;import com.google.code.morphia.EntityInterceptor;import com.google.code.morphia.Morphia;import com.google.code.morphia.mapping.MappedClass;import com.google.code.morphia.mapping.Mapper;import com.google.code.morphia.mapping.cache.EntityCache;import com.hoo.entity.User;import com.mongodb.BasicDBObjectBuilder;import com.mongodb.Mongo;import com.mongodb.MongoException;
/*** <b>function:</b> morphia对象的简单测试* @author hoojo* @createDate 2011-5-31上午11:30:20* @file MorphiaTest.java* @package com.hoo.test* @project Morphia* @blog* @email hoojo_@126.com* @version 1.0*/public class MorphiaTest {private Mongo mongo;private Morphia morphia;
@Before
public void init() {try {mongo = new Mongo();} catch (UnknownHostException e) {
e.printStackTrace();
} catch (MongoException e) {
e.printStackTrace();
}
morphia = new Morphia();
}
private void print(Object o) {if (o != null) {
System.out.println(o.toString());
}
}
/*** <b>function:</b> morphia对象的简单测试* @author hoojo*/@SuppressWarnings("deprecation")
@Test
public void testMorphia() {// 创建一个Datastore，过时的方法不推荐使用Datastore ds = morphia.createDatastore("myTestDB");print("createDatastore: " + ds);// 创建dsds = morphia.createDatastore(mongo, "myTestDB");print("createDatastore: " + ds);// 创建一个带用户名、密码的ds//ds = morphia.createDatastore(mongo, "myTestDB", "admin", new char[] { '1', '2', '3', '4', '5', '6' });
// 设置操作资源对象，这里设置User.class 就可以完成对User的一系列操作//morphia.map(User.class);//morphia.mapPackage("com.hoo.entity");//会把整个包下面的类都加载进来// 将对象转成DBObjectprint("toDBObject: " + morphia.toDBObject(new User(System.currentTimeMillis(), "jackson", true, 22, null)));// 将参数2转换成参数1的类型print("fromDBObject: " + morphia.fromDBObject(User.class, BasicDBObjectBuilder.start("sex", true).get()));print("getMapper: " + morphia.getMapper());print("isMapped: " + morphia.isMapped(User.class));
}
/*** <b>function:</b> 对Mapper对象相关操作* @author hoojo* @createDate 2012-2-16下午10:20:38*/
@Test
public void testMapper() {
Mapper mapper = morphia.getMapper();
// 添加对象映射print("addMappedClass: " + mapper.addMappedClass(User.class));//print(mapper.addMappedClass(mapper.addMappedClass(User.class));
// 创建实体缓存print("createEntityCache: " + mapper.createEntityCache());print(mapper.getCollectionName("myTestDB"));
print(mapper.getConverters());
User user = new User(System.currentTimeMillis(), "jackson", true, 22, null);
user.setId(1306814012734L);
print(mapper.getId(user));
for (EntityInterceptor ei : mapper.getInterceptors()) {System.out.println("EntityInterceptor: " + ei);
}
// 查询主键print("getKey: " + mapper.getKey(user));// 所有已经映射的classfor (MappedClass mc : mapper.getMappedClasses()) {System.out.println("getMappedClasses: " + mc);
}
print("mcMap: " + mapper.getMCMap());
print("getOptions: " + mapper.getOptions());print("keyToRef: " + mapper.keyToRef(mapper.getKey(user)));print("refToKey: " + mapper.refToKey(mapper.keyToRef(mapper.getKey(user))));
}
/*** <b>function:</b> 实体缓存* @author hoojo*/
@Test
public void testEntityCache() {
EntityCache ec = morphia.getMapper().createEntityCache();
print("EntityCache: " + ec);Datastore ds = morphia.createDatastore(mongo, "myTestDB");User user = new User(System.currentTimeMillis(), "jackson", true, 22, null);
user.setId(1306814012734L);
// 添加实体
ec.putEntity(ds.getKey(user), user);
// 代理
ec.putProxy(ds.getKey(user), user);
print("getKey: " + ds.getKey(user));print("getProxy: " + ec.getProxy(ds.getKey(user)));print("getEntity: " + ec.getEntity(ds.getKey(user)));
print(ec.exists(ds.getKey(user)));
print("stats: " + ec.stats());
}
@After
public void destory() {
mongo = null;
morphia = null;
System.gc();
}
}
四、利用Morphia完成对Datastore对象的CRUD操作
1、 首先添加如下准备代码，随后的方法直接添加到该文件中即可
package com.hoo.test.ds;
import java.net.UnknownHostException;import java.util.ArrayList;import java.util.List;import org.junit.After;import org.junit.Before;import org.junit.Test;import com.google.code.morphia.Datastore;import com.google.code.morphia.Key;import com.google.code.morphia.Morphia;import com.google.code.morphia.query.UpdateOperations;import com.hoo.entity.User;import com.mongodb.Mongo;import com.mongodb.MongoException;
/*** <b>function:</b> Datastore增删改查操作* @author hoojo* @createDate 2011-5-31下午06:29:04* @fileDatastore DatastoreTest.java* @package com.hoo.test.ds* @project Morphia* @blog* @email hoojo_@126.com* @version 1.0*/public class DatastoreTest {private Mongo mongo;private Morphia morphia;private Datastore ds;
@Before
public void init() {try {mongo = new Mongo();} catch (UnknownHostException e) {
e.printStackTrace();
} catch (MongoException e) {
e.printStackTrace();
}
morphia = new Morphia();morphia.map(User.class);ds = morphia.createDatastore(mongo, "temp");
}
private void print(Object o) {if (o != null) {
System.out.println(o.toString());
}
}
/*** <b>function:</b> 查询所有* @author hoojo* @createDate 2012-2-16 下午10:36:13*/private void query() {Iterable<User> it = ds.createQuery(User.class).fetch();while(it.iterator().hasNext()) {print("fetch: " + it.iterator().next());
}
}
@After
public void destory() {
mongo = null;
morphia = null;
ds = null;
System.gc();
}
}
2、 增删改CUD操作
/*** <b>function:</b> CUD增删改* @author hoojo* @createDate 2012-2-16 下午10:46:08*/
@Test
public void testCUD() {// 添加测试数据for (int i = 0; i < 50; i++) {User u = new User(System.currentTimeMillis() + i, "test-" + i, ((i % 2 == 0)? true: false), 18 + i, "china-gz#" + i);
print(ds.save(u));
}
//ds.delete(ds.createQuery(User.class));
List<User> users = new ArrayList<User>();users.add(new User(1306907246518L, "zhangsan", true, 22, "china-gz"));User user = new User(System.currentTimeMillis() + 3, "zhaoliu", true, 29, "china-beijin");
users.add(user);
users.add(new User(System.currentTimeMillis() + 6, "wangwu", true, 24, "china-shanghai"));users.add(new User(System.currentTimeMillis() + 9, "lisi", true, 26, "china-wuhan"));//添加集合print("save: " + ds.save(users));
//添加数组print("save: " + ds.save(users.toArray()));
this.query();print("getKey: " + ds.find(User.class, "id", 1306907246518L).getKey());
//修改操作UpdateOperations<User> uo = ds.createUpdateOperations(User.class);
print("update: " + ds.update(ds.find(User.class, "id", 1306907246518L).getKey(), uo).getUpdatedCount());uo.add("name", "zhaoliuliu").set("age", 29).set("sex", true).add("address", "gzz");print("update: " + ds.update(ds.find(User.class, "id", 1306907246518L).getKey(), uo).getUpdatedCount());
print("update: " + ds.update(ds.createQuery(User.class).field("id").equal(1306907246518L), uo).getUpdatedCount());print("update: " + ds.update(ds.find(User.class, "id", 1306907246518L), uo).getUpdatedCount());
uo = ds.createUpdateOperations(User.class);uo.set("name", "zhaoqq").set("age", 29).set("sex", true).add("address", "fzz");print("update: " + ds.update(ds.find(User.class, "id", 1306907246518L).get(), uo).getUpdatedCount());
print("update: " + ds.update(ds.createQuery(User.class).field("id").equal(1306907246518L), uo, true).getUpdatedCount());
// 修改第一个对象print("updateFirst: " + ds.updateFirst(ds.createQuery(User.class).field("id").equal(1306907246518L), uo).getUpdatedCount());//当参数createIfMissing为true的时候，如果修改的对象不存在就会添加这条数据，如果为false的情况下，不存在也不添加print("updateFirst: " + ds.updateFirst(ds.createQuery(User.class).field("id").equal(1306907246519L), uo, true).getUpdatedCount());
user.setId(1306907246518L);
print("updateFirst: " + ds.updateFirst(ds.createQuery(User.class).field("id").equal(1306907246518L), user, true).getUpdatedCount());
user.setId(1306916670518L);
// 合并print("merge: " + ds.merge(user).getId());this.query();
//删除print("delete: " + ds.delete(ds.createQuery(User.class).field("id").equal(1306907246518L)).getN());print("delete: " + ds.delete(ds.find(User.class, "age", 29).get()).getN());//print("delete: " + ds.delete(User.class, 1306911594631L).getN());//print("delete: " + ds.delete(User.class, users).getN());//ds.delete(ds.createQuery(User.class));this.query();
}
3、 Find查询操作
/*** <b>function:</b> find查询* @author hoojo* @createDate 2012-2-16 下午10:45:55*/
@Test
public void testFind() {print("find: " + ds.find(User.class).asList());//likeprint("find-contains: " + ds.find(User.class).field("name").contains("test-1").asList());//忽略大小写print("find-containsIgnoreCase: " + ds.find(User.class).field("name").containsIgnoreCase("ja").asList());
print("find-endsWith: " + ds.find(User.class).field("name").endsWith("22").asList());print("find-endsWithIgnoreCase: " + ds.find(User.class).field("name").endsWithIgnoreCase("CK").asList());
//过滤null或是没有name属性的print("find-doesNotExist: " + ds.find(User.class).field("name").doesNotExist().asList());//查询name有值的数据print("find-doesNotExist: " + ds.find(User.class).field("name").exists().asList());//age > 48print("find-greaterThan: " + ds.find(User.class).field("age").greaterThan(66).asList());//age >= 48print("find-greaterThan: " + ds.find(User.class).field("age").greaterThanOrEq(66).asList());
List<Integer> ageList = new ArrayList<Integer>();
ageList.add(22);
ageList.add(55);
ageList.add(66);
//allprint("find-hasAllOf: " + ds.find(User.class).field("age").hasAllOf(ageList).asList());//inprint("find-hasAnyOf: " + ds.find(User.class).field("age").hasAnyOf(ageList).asList());//not inprint("find-hasNoneOf: " + ds.find(User.class).field("age").hasNoneOf(ageList).asList());//elemMatch//print("find-hasThisElement: " + ds.find(User.class).field("age").hasThisElement(55).asList());print("find-hasThisOne: " + ds.find(User.class).field("age").hasThisOne(55).asList());
print("find-in: " + ds.find(User.class).field("age").in(ageList).asList());print("find-lessThan: " + ds.find(User.class).field("age").lessThan(20).asList());print("find-lessThanOrEq: " + ds.find(User.class).field("age").lessThanOrEq(18).asList());
//print("find-lessThanOrEq: " + ds.find(User.class).field("age").near(.2, .8).asList());
print("find: " + ds.find(User.class, "id", 1306813979609L).get());print("find: " + ds.find(User.class, "age", 28, 1, 2).asList());
print("findAndDelete: " + ds.findAndDelete(ds.createQuery(User.class).field("id").equal(1306813979609L)));print("find: " + ds.find(User.class).asList());
}
4、 Query查询操作
/*** <b>function:</b> query查询* @author hoojo* @createDate 2012-2-16 下午10:40:10*/
@Test
public void testQuery() {// 查询所有print("query: " + ds.createQuery(User.class).asList());// 查询主键print("query key: " + ds.createQuery(User.class).asKeyList());// 结果集数量print("query: " + ds.createQuery(User.class).countAll());// 抓取查询所有记录Iterable<User> it = ds.createQuery(User.class).fetch();while(it.iterator().hasNext()) {print("fetch: " + it.iterator().next());
}
// nullit = ds.createQuery(User.class).fetchEmptyEntities();while(it.iterator().hasNext()) {print("fetchEmptyEntities: " + it.iterator().next());
}
// all keyIterable<Key<User>> itkeys = ds.createQuery(User.class).fetchKeys();while(itkeys.iterator().hasNext()) {print("fetchKeys: " + itkeys.iterator().next());
}
// age > 24print("query: " + ds.createQuery(User.class).filter("age > ", 24).asList());// age in (20, 28)print("query: " + ds.createQuery(User.class).filter("age in ", newint[] { 20, 28 }).asList());
// limit 3print("query: " + ds.createQuery(User.class).limit(3).asList());// 分页类似MySQLprint("query: " + ds.createQuery(User.class).offset(11).limit(5).asList());// order排序，默认ascprint("query: " + ds.createQuery(User.class).order("age").asList());//descprint("query: " + ds.createQuery(User.class).order("-age").asList());// 组合排序 order by age, nameprint("query: " + ds.createQuery(User.class).order("age, name").asList());
print("query: " + ds.createQuery(User.class).queryNonPrimary().asList());print("query: " + ds.createQuery(User.class).queryPrimaryOnly().asList());//如果include 为true就表示取该属性的值，其他的默认null，反之为false则该属性为null，取其他的值print("query: " + ds.createQuery(User.class).retrievedFields(false, "age").asList());
}
5、 get和count查询
/*** <b>function:</b> get查询* @author hoojo* @createDate 2012-2-16 下午10:39:09*/
@Test
public void testGet() {User user = new User();
user.setId(1306916670518L);
print("get: " + ds.get(user));List<Long> ids = new ArrayList<Long>();
ids.add(1306907246519L);
ids.add(1306916670524L);
// 通过id集合查询相当于in ()print("get: " + ds.get(User.class, ids).asList());// id查询print("get: " + ds.get(User.class, 1306916670524L));
}
/*** <b>function:</b> count查询* @author hoojo* @createDate 2012-2-16 下午10:38:02*/
@Test
public void testGetCount() {User user = new User();
user.setId(1306916670518L);
print("getCount: " + ds.getCount(user));print("getCount: " + ds.getCount(User.class));
List<Long> ids = new ArrayList<Long>();
ids.add(1306907246519L);
ids.add(1306916670524L);
print("getCount: " + ds.getCount(ds.get(User.class, ids)));
// age > 22的记录print("getCount: " + ds.getCount(ds.createQuery(User.class).filter("age > ", 22)));// 所有print("countAll: " + ds.get(User.class, ids).countAll());print("countAll: " + ds.find(User.class).countAll());
}
6、 其他操作
@Test
public void testOthers() {
query();
/** 索引 */
ds.ensureIndexes();
// 同时用annotation也可以给指定的属性建立索引// 只需用在JavaEntity建立索引的属性上添加annotation/*@Indexed(value = IndexDirection.ASC, name = "address_index")String address;// 建立唯一索引@Indexed(value = IndexDirection.ASC, name = "bandName", unique = true)String name;*/
ds.ensureCaps();
User user = new User();
user.setId(1306916670518L);
print("getDB: " + ds.getDB());print("getDefaultWriteConcern: " + ds.getDefaultWriteConcern());print("DBColl: " + ds.getCollection(User.class)); // 查询User对象对应的集合Key<User> key = ds.getKey(user); // 主键print("getKey: " + key);print("exists: " + ds.exists(user)); //是否存在该对象print("exists: " + ds.exists(ds.getKey(user)));
print("getByKey: " + ds.getByKey(User.class, key));List<Key<User>> keys = new ArrayList<Key<User>>();
keys.add(key);
user.setId(1306916670521L);
keys.add(ds.getKey(user));
print("getByKey: " + ds.getByKeys(keys));print("getByKey: " + ds.getByKeys(User.class, keys));
query();
}
用Morphia操作对象相对比较简单，它对MongoDB对Java的操作进行了一些封装，特别是查询这方面的。有没有感觉像是在用Hibernate？
