hibernate book

If an object with the same OID (primary key) already exists in the session of hibernate save, an exception occurs. The details are as follows: Exception in thread "Main" org. hibernate. nonuniqueobjectexception: a different object with the same Identifier value was already associated with the session: [COM. unmi. loandetail #1]At org. hibernate. event. Def. abstr

Preparation You need to download the latest release versions of these projects as follows: 1. Hibernate Core, the version used here is 3.5.0-final 2. Hibernate Shards. The version 3.0.0-Beta2 is used here. 3. MySql java connector, the version used here is 5.1.12 4. slf4j, the version used here is 1.5.11 5. Install and start the mysql service, create the database hbshards in mysql, and create the test contac

Hibernate notes ----------- core interfaces of Hibernate There are five core interfaces: 1) Configuration interface: Configure Hibernate, start Hibernate at the root, and create the SessionFactory object. Hibernate applications use Configuration to obtain the object-the met

Hibernate set type ing and hibernate set ing Unordered Set elements cannot be repeated. List ordered elements can be repeated. Unordered Bag elements can be repeated. Map key-value pairs Student: Package model;Import java. util. Set;Public class Student {Private long id;Private String name;Private Set Public long getId (){Return id;}Public void setId (long id ){This. id = id;}Public String getName (){Retur

Eclipse generates Hibernate entity classes backwards from the databaseDo the project must first make the database table design, and then based on the database design to establish the entity class (VO), which is a matter of course, but in the company to do projects, let me realize, did not say that both after the database design and then "own" to establish a change VO. This means that when the project is designed, either the entity class is built accor

introduction of Hibernate framework Hibernate is a further encapsulation of JDBC. One of its main starting points is the desire to simplify the programming of Java object persistence. Because the direct use of JDBC requires programmers to write a lot of complex code. Hibernate is an open source ORM (Object-relational mapping) framework, which is a mapping betwee

Hibernate ---- N-1 (1), hibernate ---- N-1 ( * *********************** Hibernate. cfg. xml "-// Hibernate/Hibernate Configuration DTD 3.0 // EN"Http://www.hibernate.org/dtd/hibernate-configuration-3.0.dtd> ***********

First, Hibernate's core interfaceAll hibernate applications will have access to Hibernate's 5 core interfaces. (1) Configuration Interface: Configure Hibernate, start Hibernate, create Sessionfactory objects. (2) Sessionfactory interface: Initialize Hibernate, create session. (3) Session Interface: Responsible for savi

/** Author: willpower Source: rifoo Technology (http://www.rifoo.com) Time: 2006-05 Remarks: Reprinted please keep the above statement **/ Today we will end the first chapter. Let's take a look at the content generated by the database. When creating a hibernate application, if a database exists, you do not need to manage the schema. If no database exists and it is a brand new application, you need to create a database schema (The schema here refers t

June 7. Clear. " Red purple has become dust, cuckoo sound in the Shiring." The road of Mulberry hemp is endless. The beginning is known as the Taiping people.”Hibernate and Spring eclectic meet, not only the beans and beans between the lightning-like collision, but also between XML and XML in the ping water gathering. Two singular architectures, hand-lakes, not only shape the thrill of dependency injection. Also let the java EE leap Red half of the e

Label:The purpose of this blog: ① summary of their own learning process, equivalent to study notes ② to share their own experience to everyone, learn from each other, communication, not commercial content inevitably appear problems, welcome to correct, exchange, discussion, you can leave a message, can also be contacted by the following ways. I Internet technology enthusiasts, Internet technology enthusiasts Weibo: Ivan is in 0221 qq:951226918 ---------------------------------------------------

Two classes: Book and booktype) Public class book {Private long ID;Private booktype type;} Public class booktype {Private long ID;} Okay, let's start. Scenario 1 They are not correlated. Case 2 /*** @ Hibernate. Convert-to-one column = "col_booktype_id"*/Public booktype GetType (){Return type;} That is to say, a class has multiple books. For example, many books a

First, create a configuration objectThe only function of a configuration instance is to create a sessionfactory instance; If the mapping definition file is in the class load path, the AddResource () method can be used to add the mapping definition file3 Ways to configure Hibernate:using Hibernate.properties as a configuration file (\project\etc\hibernate.properties)Configuration cfg = new configuration ();//Call the AddResource method multiple times, add the mapping file Cfg.addresource ("Item.h

Generally, we will create a hibernate. cfg. xml file. This is undoubtedly good. Although the method described below is not good, it is undoubtedly a method; We can directlyCodeSet a series of parameters; Main functions: (1) configuration Config = new configuration (); // Create a configuration (2) config.Setproperties(Properties P );// Import the configuration (3) config.Addclass(Class C );// Create a ing (only the class object needs to be s

Applications can access the database through Hibernate's API, and the interfaces in the Hibernate API can be categorized into the following categories:Provides access to database operations (save, UPDATE, delete, query) interfaces, which include session, Transaction, and query interfacesInterface for configuring Hibernate: ConfigurationCallback interface, which allows the application to accept events occurr

Core interfaces of Hibernate and core interfaces of hibernate 　　1. Persistence and ORM 　　　　Persistence refers to the storage of data (Objects in memory) to persistent storage devices (such as hard disks). It is mainly used to store data in memory to relational databases, in a three-tier structure, the persistence layer focuses on implementing the logic layer of the system and associates data users with data

First, install Hibernate tools Plugin1, online installationVia the eclipse's Help->install New software online installation plugin, the plug-in connection is: Eclipse Helios (3.6) edition Add the following address: http://download.jboss.org/jbosstools/updates/stable/helios/Optional installation: Hibernate tools under the all Jboss tools node Eclipse Indigo (3.7) edition Add the f

This article has a lot of slots, in the hibernate4.x above with hibernate3.x writing to write. And there will be a lot of warnings in the program to eclipse, but that's a certain level of getting started with hibernate. After all, many of the books that introduce hibernate now are written in the hibernate3.x notation. The last time that "hibernate" is the simples

in this article. Get started After two articles, I have learned from the ground up, hoping to serve as an example. I believe that readers have a general understanding of hibernate. Hibernate is widely used in enterprise-level application development due to its ease of use and good portability. The Hibernate official website provides a good user manual. You can r

Level 1 cache, level 2 cache, and lazy loading (transfer) in Hibernate, and level 1 cache in hibernate1. Why cache? Hibernate uses cache to reduce the number of accesses to the database, thus improving the execution efficiency of hibernate. There are two types of cache in hibernate: level-1 cache and level-2 cache.2. L