通過閱讀MongoDB ?3.2.1的官方文檔中關于java 編程發現最新的文檔并沒有實現對對象到Document的映射，所以自己有了利用反射實現簡單的關系映射．

　　１．定義抽象類:AbstractMongoSession

import java.util.List;import org.bson.Document; import org.bson.conversions.Bson;import com.mongodb.client.MongoCollection; import com.mongodb.client.MongoDatabase;/** 創建一個會話實現對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:實體* * @return:void*/public abstract void save(Object obj);public abstract void saveMany(List<Object> obj);// 刪除數據public abstract long delete(Object obj) throws Exception;public abstract long delete(Bson bson) throws Exception;// 刪除數據public abstract long deleteMany(List<Object> objs);public abstract long deleteMany(Bson bson);// 修改數據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);// 查詢數據public abstract Object find(Object obj);// 獲取所有的數據public abstract List<Object> finds();// 條件查詢數據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. 實現類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. 幫助類:實現Document到Object 以及Object到Document的轉換．使用反射技術和注解．

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;/** 將mongo的文檔轉化為對象將對象轉化為mongo文檔* @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;}/** 將Bson 轉化為對象* * @param:Bson文檔* * @param:類pojo* * @param:返回對象*/public static <T> T toBean(Document document, Class<T> clazz)throws InstantiationException, IllegalAccessException,IllegalArgumentException, InvocationTargetException {T obj = clazz.newInstance();// 聲明一個對象Field[] fields = clazz.getDeclaredFields();// 獲取所有屬性Method[] methods = clazz.getMethods();// 獲取所有的方法/** 查找所有的屬性，并通過屬性名和數據庫字段名通過相等映射*/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) {// 如果字段是文檔了遞歸調用bson = toBean((Document) bson, fields[i].getType());} else if (bson instanceof MongoCollection) {// 如果字段是文檔集了調用colTOList方法 bson = colToList(bson, fields[i]);}for (int j = 0; j < methods.length; j++) {// 為對象賦值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;}/** 將對象轉化為Bson文檔* * @param:對象* * @param:類型* * @return:文檔*/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);// 獲取列注解內容NotColumn notColumn = fields[i].getAnnotation(NotColumn.class);// 獲取否列String key = null;// 對應的文檔鍵值if (null != column && null != column.name()) {// 存在列映射取值key = column.name();} else if (null != notColumn) {// 不是列的情況continue;} else {key = fields[i].getName();// 默認情況通過屬性名映射if ("id".equals(key)) {// 替換id為_idkey = "_id";}}String fieldName = fields[i].getName();/** 獲取對象屬性值并映射到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")) {// 列表處理@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 {// 其它對象處理，基本類型 document.append(key, val);}} else {// 自定義類型 document.append(key, toBson(val));}}}}return document;}/** 是否是自定義類型】* * false:是自定義*/private static boolean isJavaClass(Class<?> clz) {return clz != null && clz.getClassLoader() == null;}/** 將文檔集轉化為列表* * @param:文檔集* * @param:屬性類型* * @return:返回列表*/private static List<Object> colToList(Object bson, Field field)throws InstantiationException, IllegalAccessException,IllegalArgumentException, InvocationTargetException {ParameterizedType pt = (ParameterizedType) field.getGenericType();// 獲取列表的類型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];// 獲取元素類型@SuppressWarnings("unchecked")Object obj = toBean(child, clz);System.out.println(child);objs.add(obj);}return objs;}/** 比較setter方法和屬性相等*/private static boolean equalFieldAndSet(String field, String name) {if (name.toLowerCase().matches("set" + field.toLowerCase())) {return true;} else {return false;}}/** 比較getter方法和屬性相等*/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 "這是一個屬性映射"; } 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 "不是屬性字段"; } 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;// 每個主機的連接數private int threadsAllowedToBlockForConnectionMultiplier=30;// 線程隊列數，它以上面connectionsPerHost值相乘的結果就是線程隊列最大值。如果連接線程排滿了隊列就會拋出“Out// // to get// db”錯誤。private long maxWaitTime=5000;// 最大等待連接的線程阻塞時間private long connectTimeout=5000;// 連接超時的毫秒。0是默認和無限private long socketTimeout=5000;// socket超時。0是默認和無限private boolean autoConnectRetry=false;// 這個控制是否在一個連接時，系統會自動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)// 是否保持長鏈接.connectTimeout((int) this.connectTimeout)// 鏈接超時時間.socketTimeout((int) this.socketTimeout)// read數據超時時間.readPreference(ReadPreference.primary())// 最近優先策略.connectionsPerHost(this.connectionsPerHost)// 每個地址最大請求數.maxWaitTime((int) this.maxWaitTime)// 長鏈接的最大等待時間.threadsAllowedToBlockForConnectionMultiplier(this.threadsAllowedToBlockForConnectionMultiplier) // 一個socket最大的等待請求數.writeConcern(WriteConcern.NORMAL).build();} }

　　６．MongoDB用于生產數據庫對象

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());} }

　　

轉載于:https://www.cnblogs.com/maybo/p/5182439.html

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