MyBatis3UserGuide.docx

MyBatis3UserGuide.docx

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MyBatis3UserGuide

MyBatis3

UserGuide

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Contents

WhatisMyBatis?

.........................................................................................................................................5

GettingStarted.............................................................................................................................................5

BuildingSqlSessionFactoryfromXML.......................................................................................................5

BuildingSqlSessionFactorywithoutXML..................................................................................................6

AcquiringaSqlSessionfromSqlSessionFactory........................................................................................6

ExploringMappedSQLStatements..........................................................................................................7

ANoteaboutNamespaces....................................................................................................................8

ScopeandLifecycle..................................................................................................................................9

MapperConfigurationXML........................................................................................................................10

properties...............................................................................................................................................11

settings...................................................................................................................................................12

typeAliases.............................................................................................................................................13

typeHandlers..........................................................................................................................................14

objectFactory.........................................................................................................................................15

plugins....................................................................................................................................................16

environments.........................................................................................................................................17

transactionManager............................................................................................................................18

dataSource.........................................................................................................................................19

mappers.................................................................................................................................................21

SQLMapXMLFiles.....................................................................................................................................21

select......................................................................................................................................................22

insert,update,delete..............................................................................................................................24

sql...........................................................................................................................................................26

Parameters.............................................................................................................................................26

MyBatis3-UserGuide

29May20104

resultMap...............................................................................................................................................28

AdvancedResultMapping..................................................................................................................30

id,result.............................................................................................................................................32

SupportedJDBCTypes........................................................................................................................33

constructor.........................................................................................................................................33

association.........................................................................................................................................34

collection............................................................................................................................................37

discriminator......................................................................................................................................40

cache......................................................................................................................................................41

UsingaCustomCache.........................................................................................................................43

cache-ref................................................................................................................................................44

DynamicSQL..............................................................................................................................................44

if.............................................................................................................................................................44

choose,when,otherwise........................................................................................................................45

trim,where,set......................................................................................................................................45

foreach...................................................................................................................................................47

JavaAPI......................................................................................................................................................49

DirectoryStructure................................................................................................................................49

SqlSessions.............................................................................................................................................50

SqlSessionFactoryBuilder....................................................................................................................50

SqlSessionFactory...............................................................................................................................52

SqlSession...........................................................................................................................................54

SelectBuilder..............................................................................................................................................60

SqlBuilder...................................................................................................................................................63

MyBatis3-UserGuide

29May20105

WhatisMyBatis?

MyBatisisafirstclasspersistenceframeworkwithsupportforcustomSQL,storedproceduresand

advancedmappings.MyBatiseliminatesalmostalloftheJDBCcodeandmanualsettingofparameters

andretrievalofresults.MyBatiscanusesimpleXMLorAnnotationsforconfigurationandmap

primitives,MapinterfacesandJavaPOJOs（PlainOldJavaObjects）todatabaserecords.

GettingStarted

EveryMyBatisapplicationcentersaroundaninstanceofSqlSessionFactory.ASqlSessionFactory

instancecanbeacquiredbyusingtheSqlSessionFactoryBuilder.SqlSessionFactoryBuildercanbuilda

SqlSessionFactoryinstancefromanXMLconfigurationfile,offromacustompreparedinstanceofthe

Configurationclass.

BuildingSqlSessionFactoryfromXML

BuildingaSqlSessionFactoryinstancefromanXMLfileisverysimple.Itisrecommendedthatyouusea

classpathresourceforthisconfiguration,butyoucoulduseanyReaderinstance,includingonecreated

fromaliteralfilepathorafile:

//URL.MyBatisincludesautilityclass,calledResources,thatcontainsa

numberofmethodsthatmakeitsimplertoloadresourcesfromtheclasspathandotherlocations.

Stringresource