通过java反射实现简单的关于ＭongoDB的对象关系映射(ORM)．
2024-04-21 21:23:15
通过阅读MongoDB 3.2.1的官方文档中关于java 编程发现最新的文档并没有实现对对象到Document的映射，所以自己有了利用反射实现简单的关系映射．
１．定义抽象类:AbstractMongoSession
import java.util.List;import org.bson.Document;
import org.bson.conversions.Bson;import com.mongodb.client.MongoCollection;
import com.mongodb.client.MongoDatabase;/** 创建一个会话实现对mongoDB的原子操作* * @author:maybo* * @date:2016-2-1*/
public abstract class AbstractMongoSession {private MongoDatabase db;private Class<?> clazz;private MongoCollection<Document> collection;public MongoCollection<Document> getCollection() {return this.collection;}public Class<?> getClazz() {return clazz;}public void setDb(MongoDatabase db) {this.db = db;}public MongoDatabase getDb() {return db;}protected MongoCollection<Document> Collection(Class<?> clazz) {this.clazz = clazz;Table table = (Table) clazz.getAnnotation(Table.class);String col = null;if (null != table && null != table.name()) {col = table.name();} else {col = clazz.getName();}this.collection = db.getCollection(col);return this.collection;}/** 保存* * @param:实体* * @return:void*/public abstract void save(Object obj);public abstract void saveMany(List<Object> obj);// 删除数据public abstract long delete(Object obj) throws Exception;public abstract long delete(Bson bson) throws Exception;// 删除数据public abstract long deleteMany(List<Object> objs);public abstract long deleteMany(Bson bson);// 修改数据public abstract long upate(Bson bson, Object obj);public abstract long update(Object obj);public abstract long upateMany(Bson bson, Object obj);public abstract long upateMany(Bson bson, List<Object> objs);public abstract long upateMany(List<Object> objs);// 查询数据public abstract Object find(Object obj);// 获取所有的数据public abstract List<Object> finds();// 条件查询数据public abstract List<Object> query(Bson bson);public abstract Object queryOne(Bson bson);public abstract List<Object> query(Bson bson, Bson sort);public abstract Object queryOne(Bson bson, Bson sort);public abstract List<Object> query(Bson bson, Bson sort, int limit);public abstract List<Object> query(Bson bson, Bson sort, int limit, int skip);public abstract List<Object> query(Bson bson, Bson sort, Bson filter);public abstract Object queryOne(Bson bson, Bson sort, Bson Filter);public abstract long count();public abstract long count(Bson bson);}2. 实现类MongoSession
import java.lang.reflect.InvocationTargetException;
import java.util.ArrayList;
import java.util.List;import org.bson.Document;
import org.bson.conversions.Bson;import com.mongodb.client.FindIterable;
import com.mongodb.client.MongoCursor;
import com.mongodb.client.MongoDatabase;
import com.mongodb.client.model.Filters;
import com.mongodb.client.result.DeleteResult;
import com.mongodb.client.result.UpdateResult;public class MongoSession extends AbstractMongoSession {public MongoSession(Class<?> clazz, MongoDatabase db) {this.setDb(db);this.Collection(clazz);}/** (non-Javadoc)* * @see AbstractMongoSession#save(java.lang.Object)*/@Overridepublic void save(Object obj) {try {this.getCollection().insertOne(BsonUtil.toBson(obj));} catch (IllegalArgumentException e) {// TODO Auto-generated catch block
e.printStackTrace();} catch (SecurityException e) {// TODO Auto-generated catch block
e.printStackTrace();} catch (IllegalAccessException e) {// TODO Auto-generated catch block
e.printStackTrace();} catch (InvocationTargetException e) {// TODO Auto-generated catch block
e.printStackTrace();} catch (NoSuchFieldException e) {// TODO Auto-generated catch block
e.printStackTrace();}}@Overridepublic long delete(Object obj) throws Exception {try {DeleteResult result = this.getCollection().deleteOne(BsonUtil.toBson(obj));long count = result.getDeletedCount();return count;} catch (IllegalArgumentException e) {// TODO Auto-generated catch block
e.printStackTrace();} catch (SecurityException e) {// TODO Auto-generated catch block
e.printStackTrace();} catch (IllegalAccessException e) {// TODO Auto-generated catch block
e.printStackTrace();} catch (InvocationTargetException e) {// TODO Auto-generated catch block
e.printStackTrace();} catch (NoSuchFieldException e) {// TODO Auto-generated catch block
e.printStackTrace();}return 0;}@Overridepublic void saveMany(List<Object> obj) {try {this.getCollection().insertMany(BsonUtil.toBsons(obj));} catch (IllegalArgumentException e) {// TODO Auto-generated catch block
e.printStackTrace();} catch (SecurityException e) {// TODO Auto-generated catch block
e.printStackTrace();} catch (IllegalAccessException e) {// TODO Auto-generated catch block
e.printStackTrace();} catch (InvocationTargetException e) {// TODO Auto-generated catch block
e.printStackTrace();} catch (NoSuchFieldException e) {// TODO Auto-generated catch block
e.printStackTrace();}}@Overridepublic long delete(Bson bson) throws Exception {DeleteResult deleteResult = this.getCollection().deleteOne(bson);return deleteResult.getDeletedCount();}@Overridepublic long deleteMany(List<Object> objs) {List<Document> documents;int count = 0;try {documents = BsonUtil.toBsons(objs);for (int i = 0; null != documents && i < documents.size(); i++) {DeleteResult deleteResult = this.getCollection().deleteOne(documents.get(i));count += deleteResult.getDeletedCount();}return count;} catch (IllegalArgumentException e) {// TODO Auto-generated catch block
e.printStackTrace();} catch (SecurityException e) {// TODO Auto-generated catch block
e.printStackTrace();} catch (IllegalAccessException e) {// TODO Auto-generated catch block
e.printStackTrace();} catch (InvocationTargetException e) {// TODO Auto-generated catch block
e.printStackTrace();} catch (NoSuchFieldException e) {// TODO Auto-generated catch block
e.printStackTrace();}return count;}@Overridepublic long deleteMany(Bson bson) {DeleteResult deleteResult = this.getCollection().deleteMany(bson);return deleteResult.getDeletedCount();}@Overridepublic long upate(Bson bson, Object obj) {try {UpdateResult result = this.getCollection().updateOne(bson,new Document("$set", BsonUtil.toBson(obj)));return result.getMatchedCount();} catch (IllegalArgumentException e) {// TODO Auto-generated catch block
e.printStackTrace();} catch (SecurityException e) {// TODO Auto-generated catch block
e.printStackTrace();} catch (IllegalAccessException e) {// TODO Auto-generated catch block
e.printStackTrace();} catch (InvocationTargetException e) {// TODO Auto-generated catch block
e.printStackTrace();} catch (NoSuchFieldException e) {// TODO Auto-generated catch block
e.printStackTrace();}return 0;}@Overridepublic long update(Object obj) {Document document;try {document = BsonUtil.toBson(obj);UpdateResult updateResult = this.getCollection().updateOne(Filters.eq("_id", document.get("_id")),new Document("$set", document));return updateResult.getMatchedCount();} catch (IllegalArgumentException e) {// TODO Auto-generated catch block
e.printStackTrace();} catch (SecurityException e) {// TODO Auto-generated catch block
e.printStackTrace();} catch (IllegalAccessException e) {// TODO Auto-generated catch block
e.printStackTrace();} catch (InvocationTargetException e) {// TODO Auto-generated catch block
e.printStackTrace();} catch (NoSuchFieldException e) {// TODO Auto-generated catch block
e.printStackTrace();}return 0;}@Overridepublic long upateMany(Bson bson, Object obj) {try {UpdateResult updateResult = this.getCollection().updateMany(bson,new Document("$set", BsonUtil.toBson(obj)));return updateResult.getMatchedCount();} catch (IllegalArgumentException e) {// TODO Auto-generated catch block
e.printStackTrace();} catch (SecurityException e) {// TODO Auto-generated catch block
e.printStackTrace();} catch (IllegalAccessException e) {// TODO Auto-generated catch block
e.printStackTrace();} catch (InvocationTargetException e) {// TODO Auto-generated catch block
e.printStackTrace();} catch (NoSuchFieldException e) {// TODO Auto-generated catch block
e.printStackTrace();}return 0;}@Overridepublic long upateMany(Bson bson, List<Object> obj) {for (int i = 0; null != obj && i < obj.size(); i++) {try {UpdateResult result = this.getCollection().updateMany(bson,new Document("$set", BsonUtil.toBson(obj)));return result.getMatchedCount();} catch (IllegalArgumentException e) {// TODO Auto-generated catch block
e.printStackTrace();} catch (SecurityException e) {// TODO Auto-generated catch block
e.printStackTrace();} catch (IllegalAccessException e) {// TODO Auto-generated catch block
e.printStackTrace();} catch (InvocationTargetException e) {// TODO Auto-generated catch block
e.printStackTrace();} catch (NoSuchFieldException e) {// TODO Auto-generated catch block
e.printStackTrace();}}return 0;}@Overridepublic long upateMany(List<Object> objs) {long count = 0;for (int i = 0; null != objs && i < objs.size(); i++) {try {UpdateResult result = this.getCollection().updateMany(Filters.eq("_id",BsonUtil.toBson(objs.get(i)).get("_id")),new Document("$set", BsonUtil.toBson(objs.get(i))));count += result.getMatchedCount();} catch (IllegalArgumentException e) {// TODO Auto-generated catch block
e.printStackTrace();} catch (SecurityException e) {// TODO Auto-generated catch block
e.printStackTrace();} catch (IllegalAccessException e) {// TODO Auto-generated catch block
e.printStackTrace();} catch (InvocationTargetException e) {// TODO Auto-generated catch block
e.printStackTrace();} catch (NoSuchFieldException e) {// TODO Auto-generated catch block
e.printStackTrace();}}return count;}@Overridepublic Object find(Object obj) {try {Document document = this.getCollection().find(Filters.eq("_id", BsonUtil.toBson(obj).get("_id"))).first();return BsonUtil.toBean(document, this.getClazz());} catch (IllegalArgumentException e) {// TODO Auto-generated catch block
e.printStackTrace();} catch (SecurityException e) {// TODO Auto-generated catch block
e.printStackTrace();} catch (IllegalAccessException e) {// TODO Auto-generated catch block
e.printStackTrace();} catch (InvocationTargetException e) {// TODO Auto-generated catch block
e.printStackTrace();} catch (NoSuchFieldException e) {// TODO Auto-generated catch block
e.printStackTrace();} catch (InstantiationException e) {// TODO Auto-generated catch block
e.printStackTrace();}return null;}@Overridepublic List<Object> finds() {FindIterable<Document> doIterable = this.getCollection().find();MongoCursor<Document> cursor = doIterable.iterator();List<Object> objects = new ArrayList<Object>();while (cursor.hasNext()) {Document document = cursor.next();try {objects.add(BsonUtil.toBean(document, this.getClazz()));} catch (IllegalArgumentException e) {// TODO Auto-generated catch block
e.printStackTrace();} catch (InstantiationException e) {// TODO Auto-generated catch block
e.printStackTrace();} catch (IllegalAccessException e) {// TODO Auto-generated catch block
e.printStackTrace();} catch (InvocationTargetException e) {// TODO Auto-generated catch block
e.printStackTrace();}}return objects;}@Overridepublic List<Object> query(Bson bson) {FindIterable<Document> doIterable = this.getCollection().find(bson);MongoCursor<Document> cursor = doIterable.iterator();List<Object> objects = new ArrayList<Object>();while (cursor.hasNext()) {Document document = cursor.next();try {objects.add(BsonUtil.toBean(document, this.getClazz()));} catch (IllegalArgumentException e) {// TODO Auto-generated catch block
e.printStackTrace();} catch (InstantiationException e) {// TODO Auto-generated catch block
e.printStackTrace();} catch (IllegalAccessException e) {// TODO Auto-generated catch block
e.printStackTrace();} catch (InvocationTargetException e) {// TODO Auto-generated catch block
e.printStackTrace();}}return objects;}@Overridepublic Object queryOne(Bson bson) {Document document = this.getCollection().find(bson).first();try {return BsonUtil.toBean(document, this.getClazz());} catch (IllegalArgumentException e) {// TODO Auto-generated catch block
e.printStackTrace();} catch (InstantiationException e) {// TODO Auto-generated catch block
e.printStackTrace();} catch (IllegalAccessException e) {// TODO Auto-generated catch block
e.printStackTrace();} catch (InvocationTargetException e) {// TODO Auto-generated catch block
e.printStackTrace();}return null;}@Overridepublic List<Object> query(Bson bson, Bson sort) {FindIterable<Document> doIterable = this.getCollection().find(bson).sort(sort);MongoCursor<Document> cursor = doIterable.iterator();List<Object> objects = new ArrayList<Object>();while (cursor.hasNext()) {Document document = cursor.next();try {objects.add(BsonUtil.toBean(document, this.getClazz()));} catch (IllegalArgumentException e) {// TODO Auto-generated catch block
e.printStackTrace();} catch (InstantiationException e) {// TODO Auto-generated catch block
e.printStackTrace();} catch (IllegalAccessException e) {// TODO Auto-generated catch block
e.printStackTrace();} catch (InvocationTargetException e) {// TODO Auto-generated catch block
e.printStackTrace();}}return objects;}@Overridepublic Object queryOne(Bson bson, Bson sort) {Document document = this.getCollection().find(bson).sort(sort).first();try {return BsonUtil.toBean(document, this.getClazz());} catch (IllegalArgumentException e) {// TODO Auto-generated catch block
e.printStackTrace();} catch (InstantiationException e) {// TODO Auto-generated catch block
e.printStackTrace();} catch (IllegalAccessException e) {// TODO Auto-generated catch block
e.printStackTrace();} catch (InvocationTargetException e) {// TODO Auto-generated catch block
e.printStackTrace();}return null;}@Overridepublic List<Object> query(Bson bson, Bson sort, int limit) {FindIterable<Document> doIterable = this.getCollection().find(bson).sort(sort);if (limit > 0) {doIterable = doIterable.limit(limit);}MongoCursor<Document> cursor = doIterable.iterator();List<Object> objects = new ArrayList<Object>();while (cursor.hasNext()) {Document document = cursor.next();try {objects.add(BsonUtil.toBean(document, this.getClazz()));} catch (IllegalArgumentException e) {// TODO Auto-generated catch block
e.printStackTrace();} catch (InstantiationException e) {// TODO Auto-generated catch block
e.printStackTrace();} catch (IllegalAccessException e) {// TODO Auto-generated catch block
e.printStackTrace();} catch (InvocationTargetException e) {// TODO Auto-generated catch block
e.printStackTrace();}}return objects;}@Overridepublic List<Object> query(Bson bson, Bson sort, int limit, int skip) {FindIterable<Document> doIterable = this.getCollection().find(bson).sort(sort);if (limit > 0) {doIterable = doIterable.limit(limit);}if (skip > 0) {doIterable = doIterable.skip(skip);}MongoCursor<Document> cursor = doIterable.iterator();List<Object> objects = new ArrayList<Object>();while (cursor.hasNext()) {Document document = cursor.next();try {objects.add(BsonUtil.toBean(document, this.getClazz()));} catch (IllegalArgumentException e) {// TODO Auto-generated catch block
e.printStackTrace();} catch (InstantiationException e) {// TODO Auto-generated catch block
e.printStackTrace();} catch (IllegalAccessException e) {// TODO Auto-generated catch block
e.printStackTrace();} catch (InvocationTargetException e) {// TODO Auto-generated catch block
e.printStackTrace();}}return objects;}@Overridepublic List<Object> query(Bson bson, Bson sort, Bson filter) {FindIterable<Document> doIterable = this.getCollection().find(bson).sort(sort).filter(filter);MongoCursor<Document> cursor = doIterable.iterator();List<Object> objects = new ArrayList<Object>();while (cursor.hasNext()) {Document document = cursor.next();try {objects.add(BsonUtil.toBean(document, this.getClazz()));} catch (IllegalArgumentException e) {// TODO Auto-generated catch block
e.printStackTrace();} catch (InstantiationException e) {// TODO Auto-generated catch block
e.printStackTrace();} catch (IllegalAccessException e) {// TODO Auto-generated catch block
e.printStackTrace();} catch (InvocationTargetException e) {// TODO Auto-generated catch block
e.printStackTrace();}}return objects;}@Overridepublic Object queryOne(Bson bson, Bson sort, Bson Filter) {Document document = this.getCollection().find(bson).sort(sort).filter(Filter).first();try {return BsonUtil.toBean(document, this.getClazz());} catch (IllegalArgumentException e) {// TODO Auto-generated catch block
e.printStackTrace();} catch (InstantiationException e) {// TODO Auto-generated catch block
e.printStackTrace();} catch (IllegalAccessException e) {// TODO Auto-generated catch block
e.printStackTrace();} catch (InvocationTargetException e) {// TODO Auto-generated catch block
e.printStackTrace();}return null;}@Overridepublic long count() {return this.getCollection().count();}@Overridepublic long count(Bson bson) {// TODO Auto-generated method stubreturn this.getCollection().count(bson);}
}3. 帮助类:实现Document到Object 以及Object到Document的转换．使用反射技术和注解．
import java.lang.reflect.Field;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.lang.reflect.ParameterizedType;
import java.util.ArrayList;
import java.util.List;import org.bson.Document;
import com.mongodb.client.MongoCollection;
import com.mongodb.client.MongoCursor;/** 将mongo的文档转化为对象将对象转化为mongo文档* @author:maybo* @data:2016-2-1*/
public class BsonUtil {public static <T> List<T> toBeans(List<Document> documents, Class<T> clazz)throws IllegalArgumentException, InstantiationException,IllegalAccessException, InvocationTargetException {List<T> list = new ArrayList<T>();for (int i = 0; null != documents && i < documents.size(); i++) {list.add(toBean(documents.get(i), clazz));}return list;}/** 将Bson 转化为对象* * @param:Bson文档* * @param:类pojo* * @param:返回对象*/public static <T> T toBean(Document document, Class<T> clazz)throws InstantiationException, IllegalAccessException,IllegalArgumentException, InvocationTargetException {T obj = clazz.newInstance();// 声明一个对象Field[] fields = clazz.getDeclaredFields();// 获取所有属性Method[] methods = clazz.getMethods();// 获取所有的方法/** 查找所有的属性，并通过属性名和数据库字段名通过相等映射*/for (int i = 0; i < fields.length; i++) {String fieldName = fields[i].getName();Column column = fields[i].getAnnotation(Column.class);Object bson = null;if (null != column && null != column.name()) {bson = document.get(column.name());} else if ("id".equals(fieldName)) {bson = document.get("_id");} else {bson = document.get(fieldName);}if (null == bson) {continue;} else if (bson instanceof Document) {// 如果字段是文档了递归调用bson = toBean((Document) bson, fields[i].getType());} else if (bson instanceof MongoCollection) {// 如果字段是文档集了调用colTOList方法
bson = colToList(bson, fields[i]);}for (int j = 0; j < methods.length; j++) {// 为对象赋值String metdName = methods[j].getName();if (equalFieldAndSet(fieldName, metdName)) {methods[j].invoke(obj, bson);break;}}}return obj;}public static List<Document> toBsons(List<Object> objs)throws IllegalArgumentException, SecurityException,IllegalAccessException, InvocationTargetException,NoSuchFieldException {List<Document> documents = new ArrayList<Document>();for (int i = 0; null != objs && i < objs.size(); i++) {documents.add(toBson(objs.get(i)));}return documents;}/** 将对象转化为Bson文档* * @param:对象* * @param:类型* * @return:文档*/public static Document toBson(Object obj) throws IllegalArgumentException,IllegalAccessException, InvocationTargetException,SecurityException, NoSuchFieldException {if (null == obj) {return null;}Class<? extends Object> clazz = obj.getClass();Document document = new Document();Method[] methods = clazz.getDeclaredMethods();Field[] fields = clazz.getDeclaredFields();for (int i = 0; null != fields && i < fields.length; i++) {Column column = fields[i].getAnnotation(Column.class);// 获取列注解内容NotColumn notColumn = fields[i].getAnnotation(NotColumn.class);// 获取否列String key = null;// 对应的文档键值if (null != column && null != column.name()) {// 存在列映射取值key = column.name();} else if (null != notColumn) {// 不是列的情况continue;} else {key = fields[i].getName();// 默认情况通过属性名映射if ("id".equals(key)) {// 替换id为_idkey = "_id";}}String fieldName = fields[i].getName();/** 获取对象属性值并映射到Document中*/for (int j = 0; null != methods && j < methods.length; j++) {String methdName = methods[j].getName();if (null != fieldName && equalFieldAndGet(fieldName, methdName)) {Object val = methods[j].invoke(obj);// 得到值if (null == val) {continue;}if (isJavaClass(methods[j].getReturnType())) {if (methods[j].getReturnType().getName().equals("java.util.List")) {// 列表处理@SuppressWarnings("unchecked")List<Object> list = (List<Object>) val;List<Document> documents = new ArrayList<Document>();for (Object obj1 : list) {documents.add(toBson(obj1));}document.append(key, documents);} else {// 其它对象处理，基本类型
document.append(key, val);}} else {// 自定义类型
document.append(key, toBson(val));}}}}return document;}/** 是否是自定义类型】* * false:是自定义*/private static boolean isJavaClass(Class<?> clz) {return clz != null && clz.getClassLoader() == null;}/** 将文档集转化为列表* * @param:文档集* * @param:属性类型* * @return:返回列表*/private static List<Object> colToList(Object bson, Field field)throws InstantiationException, IllegalAccessException,IllegalArgumentException, InvocationTargetException {ParameterizedType pt = (ParameterizedType) field.getGenericType();// 获取列表的类型List<Object> objs = new ArrayList<Object>();@SuppressWarnings("unchecked")MongoCollection<Document> cols = (MongoCollection<Document>) bson;MongoCursor<Document> cursor = cols.find().iterator();while (cursor.hasNext()) {Document child = cursor.next();@SuppressWarnings("rawtypes")Class clz = (Class) pt.getActualTypeArguments()[0];// 获取元素类型@SuppressWarnings("unchecked")Object obj = toBean(child, clz);System.out.println(child);objs.add(obj);}return objs;}/** 比较setter方法和属性相等*/private static boolean equalFieldAndSet(String field, String name) {if (name.toLowerCase().matches("set" + field.toLowerCase())) {return true;} else {return false;}}/** 比较getter方法和属性相等*/private static boolean equalFieldAndGet(String field, String name) {if (name.toLowerCase().matches("get" + field.toLowerCase())) {return true;} else {return false;}}
}４．用到的注解Column ,NotColumn,Table
Column:
import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;@Target(ElementType.FIELD)
@Retention(RetentionPolicy.RUNTIME)
public @interface Column {public String name();public String text() default "这是一个属性映射";
}
N otColumn:
import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;@Target(ElementType.FIELD)
@Retention(RetentionPolicy.RUNTIME)
public @interface NotColumn {public String text() default "不是属性字段";
}
Table:
import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;@Target(ElementType.TYPE)
@Retention(RetentionPolicy.RUNTIME)
public @interface Table {public String name();public String text() default "表格映射";
}
5. MongoObject
import java.util.ArrayList;
import java.util.List;
import com.mongodb.MongoClient;
import com.mongodb.MongoClientOptions;
import com.mongodb.ReadPreference;
import com.mongodb.ServerAddress;
import com.mongodb.WriteConcern;public class MongoObject {private List<String> hostPorts;private int port=27017;private String host="127.0.0.1";private int connectionsPerHost=5;// 每个主机的连接数private int threadsAllowedToBlockForConnectionMultiplier=30;// 线程队列数，它以上面connectionsPerHost值相乘的结果就是线程队列最大值。如果连接线程排满了队列就会抛出“Out// // to get// db”错误。private long maxWaitTime=5000;// 最大等待连接的线程阻塞时间private long connectTimeout=5000;// 连接超时的毫秒。0是默认和无限private long socketTimeout=5000;// socket超时。0是默认和无限private boolean autoConnectRetry=false;// 这个控制是否在一个连接时，系统会自动public void setHostPorts(List<String> hostPorts) {this.hostPorts = hostPorts;}public MongoObject() {// TODO Auto-generated constructor stub}public int getPort() {return port;}public void setPort(int port) {this.port = port;}public String getHost() {return host;}public void setHost(String host) {this.host = host;}public int getConnectionsPerHost() {return connectionsPerHost;}public void setConnectionsPerHost(int connectionsPerHost) {this.connectionsPerHost = connectionsPerHost;}public int getThreadsAllowedToBlockForConnectionMultiplier() {return threadsAllowedToBlockForConnectionMultiplier;}public void setThreadsAllowedToBlockForConnectionMultiplier(int threadsAllowedToBlockForConnectionMultiplier) {this.threadsAllowedToBlockForConnectionMultiplier = threadsAllowedToBlockForConnectionMultiplier;}public long getMaxWaitTime() {return maxWaitTime;}public void setMaxWaitTime(long maxWaitTime) {this.maxWaitTime = maxWaitTime;}public long getConnectTimeout() {return connectTimeout;}public void setConnectTimeout(long connectTimeout) {this.connectTimeout = connectTimeout;}public long getSocketTimeout() {return socketTimeout;}public void setSocketTimeout(long socketTimeout) {this.socketTimeout = socketTimeout;}public boolean isAutoConnectRetry() {return autoConnectRetry;}public void setAutoConnectRetry(boolean autoConnectRetry) {this.autoConnectRetry = autoConnectRetry;}public MongoClient run() {if (null != hostPorts) {if (null != host && port > 0) {hostPorts.add(host + ":" + port);}} else {hostPorts = new ArrayList<String>();if (null != host && port > 0) {hostPorts.add(host + ":" + port);} else {return null;}}List<ServerAddress> addresses = new ArrayList<ServerAddress>();for (String hostPort : hostPorts) {String[] spits = hostPort.split(":");ServerAddress address = new ServerAddress(spits[0],Integer.valueOf(spits[1]));addresses.add(address);}MongoClient client = new MongoClient(addresses, getConfOptions());return client;}@SuppressWarnings("deprecation")private MongoClientOptions getConfOptions() {return new MongoClientOptions.Builder().socketKeepAlive(true)// 是否保持长链接.connectTimeout((int) this.connectTimeout)// 链接超时时间.socketTimeout((int) this.socketTimeout)// read数据超时时间.readPreference(ReadPreference.primary())// 最近优先策略.connectionsPerHost(this.connectionsPerHost)// 每个地址最大请求数.maxWaitTime((int) this.maxWaitTime)// 长链接的最大等待时间.threadsAllowedToBlockForConnectionMultiplier(this.threadsAllowedToBlockForConnectionMultiplier) // 一个socket最大的等待请求数.writeConcern(WriteConcern.NORMAL).build();}
}
６．MongoDB用于生产数据库对象
import com.mongodb.client.MongoDatabase;public class MongoDB{private String db;private MongoObject client;public void setClient(MongoObject client) {this.client = client;}public void setDb(String db) {this.db = db;}
public MongoDB(MongoObject client,String db){this.client=client;this.db=db;
}
public MongoDatabase excute(){return client.run().getDatabase(db);
}
}
７．DaoImpl
import java.util.List;public class DaoImpl implements Dao{private MongoTemplate template;
private MongoSession session;
private String className;
public void setClassName(String className) {this.className = className;
}
public MongoSession getSession() {return session;
}
public DaoImpl(){}
public DaoImpl(MongoTemplate template,String className){this.template = template;this.className=className;try {this.session=template.session(Class.forName(className));} catch (ClassNotFoundException e) {// TODO Auto-generated catch block
e.printStackTrace();}
}
public void setTemplate(MongoTemplate template) {this.template = template;try {this.session=template.session(Class.forName(className));} catch (ClassNotFoundException e) {// TODO Auto-generated catch block
e.printStackTrace();}
}@Overridepublic void save(Object obj) {this.session.save(obj);}@Overridepublic void delete(Object obj) {try {this.session.delete(obj);} catch (Exception e) {// TODO Auto-generated catch block
e.printStackTrace();}}@Overridepublic void update(Object obj) {this.session.update(obj);}@Overridepublic Object find(Object obj) {// TODO Auto-generated method stubreturn this.session.find(obj);}@Overridepublic List<Object> finds() {// TODO Auto-generated method stubreturn this.session.finds();}@Overridepublic long total() {// TODO Auto-generated method stubreturn this.session.count();}@Overridepublic List<Object> finds(int index, int offset) {// TODO Auto-generated method stubreturn this.session.query(null, null, offset, index);}}8. Test
public class MongoDBTest {private static MongoTemplate template1;private static MongoTemplate template2;private static MongoTemplate template3;private static Dao dao1;private static Dao dao2;private static Dao dao3;static {MongoObject mongoObject = new MongoObject();mongoObject.setPort(12345);MongoDB demo1 = new MongoDB(mongoObject, "demo1");MongoDB demo2 = new MongoDB(mongoObject, "demo2");MongoDB demo3 = new MongoDB(mongoObject, "demo3");template1 = new MongoTemplate(demo1);template2 = new MongoTemplate(demo2);template3 = new MongoTemplate(demo3);dao1 = new DaoImpl(template1, "MidStu");dao2 = new DaoImpl(template2, "MidStu");dao3 = new DaoImpl(template3, "MidStu");}@Testpublic void save() {MidStu midStu = new MidStu();midStu.setHabit("zuqiu");midStu.setId("saflfgsddsf35");dao1.save(midStu);MidStu midStuFind = new MidStu();midStuFind.setId("saflfgsddsf35");System.out.println(dao1.find(midStuFind).toString());dao2.save(midStu);System.out.println(dao2.find(midStuFind).toString());dao3.save(midStu);System.out.println(dao3.find(midStuFind).toString());}
}
转载于:https://www.cnblogs.com/maybo/p/5182439.html
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