MongoDB JDBC Basic Use __mongodb

MongoDB Introductory Column

Http://blog.csdn.net/column/details/19681.html

Java Connection MongoDB
MongoDB provides a range of drivers for supporting various languages to connect MongoDB databases, including: java,python,c++,scala,php, complete driver list: https://docs.mongodb.com/manual/ Applications/drivers/index.html

This provides Java with Mongo-java-driver library support MONGO JDBC driver, which can be used as long as it is imported in Project dependencies: Org.mongodb:mongo-java-driver as in projects built using Gradle, the following import:

Compile ' org.mongodb:mongo-java-driver:3.6.3 '

Mongo JDBC Driver Documentation home: http://mongodb.github.io/mongo-java-driver/;
You can query the driver's detailed usage of the drive home page, the sample basic use, including: database connection, curd operation, use version: MongoDB 3.6,mongo-java-driver 3.6, different versions of the driver API by a number of differences, please query the driver document details;
Sample database Collection Testdb.blog Documentation example is as follows:

{

"_id": ObjectId ("5a8d519a07c9086ee823f15d"),

"title": "Mysql Overview",

"description": "Musql is a RDBMS",

"Author": "Assad",

"url": "http://blog.assad.article/233",

"Tages": ["MySQL", "RDBMS", "SQL"],

"Likes": 200

}

Database Connection 1) No authentication connection

Mongoclient mongoclient = new Mongoclient ("127.0.0.1", 27017);

Or use the MONGO URI

Mongoclient mongoclient = new Mongoclient (New Mongoclienturi ("mongodb://127.0.0.1:27017"));

2) Verify the connection

String user = "Assad"; User name

String database = "TestDB"; Database

char[] Password = "123". ToCharArray (); Password

Mongocredential credential = mongocredential.createcredential (User,database,password); Validating objects

Mongoclientoptions options = Mongoclientoptions.builder (). sslenabled (False). build (); Connection Action Object

Mongoclient mongoclient = new Mongoclient (New ServerAddress ("127.0.0.1", 27017), credential,options); Connection objects

Or use the MONGO URI

Mongoclient mongoclient = new Mongoclient (New Mongoclienturi ("mongodb://assad:123@127.0.0.1:27017/?authsource= Testdb&ssl=false "));

The authentication connection format for the MONGO URI is as follows: mongodb://username:password@host/?authsource=databasename&ssh=true;

Get Database & Collection

Get the specified Database object

Mongodatabase db = Mongoclient.getdatabase ("TestDB");

Gets the specified Collection object

mongocollection<document> blogs = db.getcollection ("blog");

Enumerate all database names

For (String DbName:blogs.listDatabaseNames ()

System.out.println (dbname);

Enumerates all collection names in the specified database

For (String colName:db.listCollectionNames ())

System.out.println (colname);

In the following example, the output for the document result is standard output using Log4j2;

Select query Operations
1) Query results traversalIn MongoDB JDBC, a Finditerable<document> object is generated for the query result that can be iterated by obtaining its iterator, and the object also provides a foreach method, passing in a block object, The results can be blocked iterations;

Database connection

Mongoclient mongoclient = new Mongoclient (New Mongoclienturi ("mongodb://assad:123@127.0.0.1:27017/?authsource= Testdb&ssl=false "));

mongocollection<document> blogs = mongoclient.getdatabase ("TestDB"). GetCollection ("blog");

Querying all documents, traversing output results

For (Document Document1:blogs.find ())

Log.debug (Document1.tojson ());

Querying all documents, traversing the results using the Walker

mongocursor<document> cursor = Blogs.find (). iterator ();

while (Cursor.hasnext ())

Log.debug (Cursor.next (). Tojson ());

Query all documents and use blocking callback method for all results

Blogs.find (). ForEach (block<document>) Document-> {

Log.debug (Document.tojson ());

});

Query all documents, Get Title field (string), likes field (Int32), tags field (array) in the resulting document

Blogs.find (). ForEach (block<document>) Document->{

String title = document.getstring ("title");

int likes = Document.getinteger ("likes");

list<string> tags = (list<string>) document.get ("tags");

Log.debug (title + "-" + Likes + "-" + tags);

});

2) Condition InquiryFor conditional query, we can construct a nested document object, produce a document chain similar to MongoDB query syntax, or use various static methods in Filters (such as eq,lte, etc.) to query functions, MongoDB JDBC has encapsulated most of the MONGODB query condition operators as functional calls;

Conditional query: Db.blog.find ({"Author": "Assad"})

Blogs.find (New Document ("author", "Assad")). ForEach ((block<document>) Document-> {

Log.debug (Document.tojson ());

});

Blogs.find (eq ("author", "Assad")). ForEach ((block<document>) Document-> {

Log.debug (Document.tojson ());

});

Conditional query: Db.blog.find ({"likes": {$gte: $, $lte: 500}})

Blogs.find (New document ("Likes", New Document ("$gte"). Append ("$lte", 500))

  . ForEach ((block<document>) Document-> {

Log.debug (Document.tojson ());

});

Blogs.find (GTE ("likes"), LTE ("likes", 500))

  . ForEach ((block<document>) Document-> {

Log.debug (Document.tojson ());

});

Conditional query: Db.blog.find ({"Author": "Assad", "title":/mongodb*/i})

Blogs.find (New document ("Author", "Assad"). Append ("title", New Document ("$regex",