Ibatis configuration file details

The basic ibatis code includes: <br/> 1. ibatis instance configuration <br/> A typical configuration file is as follows (see the following for details about the configuration items): <br/> <? XML version = "1.0" encoding = "UTF-8"?> <Br/> <! Doctype sqlmapconfig <br/> Public "-// ibatis.com//dtd SQL map config 2.0/<br/>" [url] scheme </P> <p> <sqlmapconfig> </P> <p> <Settings <br/> cachemodelsenabled = "true" <br/> enhancementenabled = "true" <br/> lazyloadingenabled = "true" <br/> errortracingenabled = "true ""<br/> maxrequests =" 32 "<br/> maxsessions =" 10 "<br/> maxtransactions =" 5 "<br/> usesta Tementnamespaces = "false" <br/> </P> <p> <transactionmanager type = "JDBC"> <br/> <datasource type = "simple"> <br /> <property name = "JDBC. driver "value =" com. p6spy. engine. spy. p6spydriver "/> <br/> <property name =" JDBC. connectionurl "value =" JDBC: mysql: // localhost/sample "/> <br/> <property name =" JDBC. username "value =" user "/> <br/> <property name =" JDBC. password "value =" mypass "/> <br /> <Property name = "pool. maximumactiveconnections "value =" 10 "/> <br/> <property name =" pool. maximumidleconnections "value =" 5 "/> <br/> <property name =" pool. maximumcheckouttime "value =" 120000 "/> <br/> <property name =" pool. timetowait "value =" 500 "/> <br/> <property name =" pool. pingquery "value =" select 1 from account "/> <br/> <property name =" pool. pingenabled "value =" false "/> <br/> <Property name = "pool. pingconnectionsolderthan "value =" 1 "/> <br/> <property name =" pool. pingconnectionsnotusedfor "value =" 1 "/> <br/> </datasource> <br/> </transactionmanager> </P> <p> <sqlmap resource =" com/ibatis /sample/user. XML "/> </P> <p> </sqlmapconfig> (1) settings node <br/> cachemodelsenabled <br/> whether to enable the cache mechanism on sqlmapclient. We recommend that you set this parameter to "true" <br/> enhancementenabled <br/> whether to enable bytecode for pojo to enhance the call efficiency of getter/setter and avoid performance overhead caused by reflect. This also improves lazy loading. We recommend that you set it to "true" <br/> errortracingenabled <br/> whether to enable error logs, we recommend that you set this parameter to "true" during development to facilitate debugging <br/> lazyloadingenabled <br/> whether to enable the delayed loading mechanism, it is recommended to set it to "true" <br/> maxrequests <br/> maximum number of concurrent requests (statement concurrency) <br/> maxtransactions <br/> maximum number of concurrent transactions <br/> maxsessions maximum number of sessions. That is, the maximum number of concurrent sqlmapclients allowed currently. <Br/> usestatementnamespaces <br/> whether to use the statement namespace. <Br/> The namespace here refers to the namespace attribute of the sqlmap section in the ing file. For example, the sqlmap node of the t_ing file for the t_use <br/> table in the preceding example: <sqlmap namespace = "user"> operations defined under this sqlmap node belong to the "user" namespace. When usestatementnamespaces = "true", the statement call needs to append the namespace, for example, sqlmap. update ("user. updateuser ", user); <br/> otherwise, it can be called directly by the statement name, for example, sqlmap. update ("updateuser", user); note that the statement definition does not have a duplicate name in all ing files. <Br/> transactionmanager node <br/> the transactionmanager node defines the ibatis Transaction Manager. Currently, it provides the following options: <br/> jdbc <br/> using traditional JDBC connection. commit/rollback implement transaction support. <Br/> JTA <br/> use the JTA service provided by the container to implement global transaction management. <Br/> external transaction management. For example, if ibatis is used in ejbs, you can use the EJB deployment configuration to implement a self-initiated transaction management mechanism. <br/>. In this case, ibatis delegates all transactions to external containers for management. <Br/> datasource node <br/> datasource belongs to the transactionmanager node and is used to set the datasource attribute used during ibatis runtime. <Br/> type attribute: <br/> the type attribute of the datasource node specifies the implementation type of datasource. Optional items: <br/> simple is the built-in datasource Implementation of ibatis, which implements a simple <br/> database connection pool mechanism, the corresponding ibatis implementation class is <br/> COM. ibatis. sqlmap. engine. datasource. simpleperformancefactory. <Br/> DBCP: <br/> datasource encapsulation Based on the Apache DBCP connection pool component. This option is recommended when no container is provided <br/> for datasource service, the corresponding ibatis implementation class is <br/> COM. ibatis. sqlmap. engine. datasource. dbcpperformancefactory. <Br/> JNDI: <br/> the datasource implementation provided by the J2EE container is used. datasource is obtained from the container by specifying the <br/> JNDI name. The corresponding ibatis implementation class is <br/> com. ibatis. sqlmap. Engine. datasource. jndidatasourcefactory. <Br/> description of child nodes of datasource (simple & DBCP): <br/> JDBC. Driver JDBC driver. <Br/> for example, org. gjt. Mm. MySQL. Driver. JDBC. connectionurl <br/> Database URL. <Br/> For example: JDBC: mysql: // localhost/sample <br/> If sqlserver JDBC driver is used, you need to append selectmethod = cursor after the URL to obtain multi-statement support for JDBC transactions. <Br/> JDBC. username <br/> database username <br/> JDBC. password <br/> Database User Password <br/> pool. maximumactiveconnections <br/> maximum capacity that can be maintained by the database connection pool. <Br/> pool. maximumidleconnections <br/> Number of suspended (idle) connections allowed in the database connection pool. <Br/> most of the configuration of JNDI is performed on the application server, so the configuration in ibatis is relatively simple <br/> use the jdni configuration of JDBC and JTA transaction management respectively: <br/> Configure the JNDI datasource using JDBC transaction management <br/> <transactionmanager type = "JDBC"> <br/> <datasource type = "JNDI"> <br/> <property name = "datasource" value = "Java: COMP/ENV/jdbc/mydatasource "/> <br/> </datasource> <br/> </transactionmanager> <br/> <transactionmanager type =" JTA "> <br /> <property name = "usertransaction" value = "J Ava:/CTX/CON/usertransaction "/> <br/> <datasource type =" JNDI "> <br/> <property name =" datasource "value =" Java: COMP/ENV/jdbc/mydatasource "/> <br/> </datasource> sqlmap node <br/> the sqlmap node specifies the location of the ing file, multiple sqlmap nodes can appear in the configuration to specify all the ing files contained in the <br/> project. <Br/> basic ibatis semantics <br/> xmlsqlmapclientbuilder is a new component introduced in later versions of ibatis 2.0. It is used to replace xmlsqlmapbuilder in version 1.x< br/>. The function is to create a sqlmapclient instance based on the configuration file. <Br/> sqlmapclient is a core component of ibatis and provides a basic platform for data operations. Sqlmapclient <br/> can be created through xmlsqlmapclientbuilder: <br/> string resource = "com/ibatis/sample/sqlmapconfig. XML "; <br/> reader; </P> <p> reader = resources. getresourceasreader (Resource); </P> <p> xmlsqlmapclientbuilder xmlbuilder = <br/> New xmlsqlmapclientbuilder (); </P> <p> sqlmapclient sqlmap = xmlbuilder. buildsqlmap (Reader); "com/ibatis/sample/sqlmapconfig. XML indicates the relative path of the configuration file in classpath <br/>. Xmlsqlmapclientbuilder creates a sqlmapclient instance based on the configuration parameters by accepting a reader-type configuration file <br/> handle. <Br/> sqlmapclient provides many data operation methods. The following are examples of common methods. For more information, see ibatis Java Doc or ibatis official development manual. <Br/> sqlmapclient basic operation example <br/> The following example is taken from the ibatis official development manual. The author re-typeset it for better reading. <Br/> Example 1: insert, update, delete: <br/> sqlmap. starttransaction (); <br/> product Product = new product (); <br/> product. setid (1); <br/> product. setdescription ("shih tzu"); <br/> int rows = sqlmap. insert ("insertproduct", product); <br/> sqlmap. committransaction (); Example 2: Data Query (select) <br/> sqlmap. starttransaction (); <br/> integer key = new INTEGER (1); <br/> product Product = (product) sqlmap. queryforobject ("getproduct", key); <br/> sqlmap. committransaction (); Example 3: store the query result (select) in the specified object <br/> sqlmap. starttransaction (); <br/> customer = new customer (); <br/> sqlmap. queryforobject ("getcust", parameterobject, customer); <br/> sqlmap. queryforobject ("getaddr", parameterobject, customer); <br/> sqlmap. committransaction (); example 4: execute a batch query (select) <br/> sqlmap. starttransaction (); <br/> List list = sqlmap. queryforlist ("getproductlist", null) <br/> sqlmap. committransaction (); example 5: About autocommit <br/> // when starttransaction is not executed in advance, the default mode is auto_commit <br/> int rows = sqlmap. insert ("insertproduct", product); Example 6: query data within a specified range <br/> sqlmap. starttransaction (); <br/> List list = sqlmap. queryforlist ("getproductlist", null, 0, 40); <br/> sqlmap. committransaction (); Example 7: Query with rowhandler (select) <br/> public class myrowhandler implements rowhandler {<br/> Public void handlerow (Object object, list List) throws <br/> sqlexception {<br/> product Product = (product) object; <br/> product. setquantity (10000); <br/> sqlmap. update ("updateproduct", product); <br/>}< br/> sqlmap. starttransaction (); <br/> rowhandler = new myrowhandler (); <br/> List list = sqlmap. queryforlist ("getproductlist", null, <br/> rowhandler); <br/> sqlmap. committransaction (); // Example 8: Paging query (select) <br/> paginatedlist list = <br/> sqlmap. queryforpaginatedlist ("getproductlist", null, 10); <br/> list. nextpage (); <br/> list. previouspage (); // Example 9: map-based batch query (select) <br/> sqlmap. starttransaction (); <br/> map = sqlmap. queryformap ("getproductlist", null, "productcode"); <br/> sqlmap. committransaction (); <br/> product P = (product) map. get ("EST-93 ");