mapper lithography

In the actual application, there will be more mapper. If each new mapper is added, it will be inconvenient to add the corresponding configuration file to the Sqlmapconfig.You can create a new package, place Mapper.java underneath it, and place the same named Mapper.xml under it.In this way, you can use Be aware of the. Java and. XML naming, and Mapper.xml namespace.First,

Following the previous example project Http://www.cnblogs.com/EasonJim/p/7083165.html, using the Configdecoratormapper Mapper, the page under the specified directory is the same as the template page.On the use, just set two places, no configuration on the basic page.1, Decorators.xmlXML version= "1.0" encoding= "UTF-8"?>DecoratorsDefaultDir= "/decorators"> Decoratorname= "Basic-theme"page= "basic-theme.jsp"> Decorator>Decorators>2, Sitem

Because DAO development, will create entity class object every time, will pass in fixed query value such as ID, there is hard coding problem, so adopt mapper dynamic proxy (do not create entity class object, need interface only, automatically generate by mapper) as before MyBatis (a) step, However, you need to make changes to the Mapper.xml file:Namespace: must be the full path of the interface class (ID: M

1. Create a new MyBatis folder in the src/main/resources/directory and put the Xxx.xml file in the folder2. Configure in the Application.yml file:MyBatisConfigurationMapunderscoretocamelcase:trueMapperlocations:mybatis/*mapper.xml3, in the DAO interface file annotated @mapper, note that the interface method on the SQL statement to remove@Mapper Public Interfacemrinfomapper{/*** Query Mr Information on condi

. @Case Method The value of the singleton instance and its corresponding mapping. Properties: Value,type,results. The Results property is an array of results, so this annotation is similar to the actual resultmap, as specified by the following Results annotation. @Results Method A list of result mappings that contains details of how a particular result column is mapped to a property or field. Property: Value, which is an array of Result annotatio

1. MapReduce Code EntryNew // sets the MapReduce input format job.waitforcompletion (true);2. InputFormat Analysis Public Abstract class Inputformat { // Gets the shard of the input file, is only a logical shard, and does not have a physical shard public Abstract list getsplits (jobcontext context); // Create Recordreader to read Data from Inputsplit Public Abstract Recordreader Createrecordreader (inputsplit split,taskattemptcontext context);}Different InputFormat will imp

Mybaits3 source code analysis (2): Scan Mapper to associate with spring IOC container, mybaits3ioc First, let's talk about how mapper is configured to an object. All interfaces that implement classes specified by markerInterface under basePackage will be scanned and parsed. Mapperscannerproceser implements the BeanDefinitionRegistryPostProcessor (BeanDefinitionRegistry postprocessor, think about Spring AOP

How to determine Mapper quantity for Hadoop-2.4.1 Learning The advantage of MapReduce framework is that it can run mapper and reducer tasks in parallel in the cluster. How can we determine the number of mapper and reducer tasks, or how does Hadoop programmatically control the number of ER er and reducer started by jobs? In the

Intellij idea plug-in development-Quickly locate SQL IN THE mybatis mapper file and intellijmybatis Intellij idea provides openApi, through which we can develop our own plug-ins to improve work efficiency. You can directly paste a link here to get started with the demo. http://www.jianshu.com/p/2427e4cfd3e9, you can also find it online .. I use intellij idea 2017 and jdk 1.8 or above. Step 1: New project, select IntelliJ Plaltform Plugin, Click Next,

testing the code we wrote.There are some problems with this development:There is a lot of duplicate code in the implementation class of the 1.dao interface, which increases the programmer's workload.2. In the implementation class, the Sqlsession method hard-encodes the statement ID (where "Test.finduserbyid" is the ID of statment) when invoking the SQL statement in the map file.　　　　3. The variable passed in when the Sqlsession method is called, because the Sqlsession method uses generics, even

Currently MyBatis in addition to the SQL can be configured through XML, but also through the form of annotations to configure SQL, this article mainly describes how MyBatis is handling annotated SQL mapping, through the source code analysis processXML configurationParsing process private void Mapperelement (xnode parent) throws Exception {//If the Mapper node is configured in the configuration (parent! = NULL) { For (XNode Child:parent.getCh

When defining a Mapper interface (Userdao), we do not need to implement this class, but Sqlsession.getmapper () eventually returns an object that implements the interface. This object is implemented by MyBatis using the dynamic proxy of JDK. Here we will introduce the generation process of this proxy object and the implementation process of its method. The mapper code object's build Process Defaultsqlsessio

); SYSTEM.OUT.PRINTLN (user); }} Configuration Mode 2Enable the spring scanner to comment out the original usermapper beanMapper Configuration Mapperfactorybean: Generate proxy objects based on mapper interface - - mapper batch scan, scan out the Mapper interface from the Mapper package,

Mybatis framework 3: dao layer development, Mapper dynamic proxy development, and mybatismapper Here is the most basic building: http://www.cnblogs.com/xuyiqing/p/8600888.html Next we achieve a simple addition, deletion, modification, query: http://www.cnblogs.com/xuyiqing/p/8601506.html However, it is found that the code is too repetitive. Next we will integrate and implement DAO development: I. Original DAO development: package dao;import pojo.Use

1, create the Mybatis-config.xml file, in the file to complete and database connection settings operationXML version= "1.0" encoding= "UTF-8"?>DOCTYPE configuration Public "-//mybatis.org//dtd Config 3.0//en" "Http://mybatis.org/dtd/mybatis-3-config.dtd">Configuration>PropertiesResource= "Db.properties"/>Typealiases>Two methods to use, it is recommended to use the second--PackageName= "Com.huawei.bean"/>Typealiases>EnvironmentsDefault= "Development">EnvironmentId= "Development">Configuring trans

Colleagues for help, said the restart of Debian, the system hangs.Report the following error```Loading, please wait .../dev/mapper/debian--vg-root contains a file system with Errors,check the file system./dev/mapper/debian-vg-root:Inodes that were part of a corrupted orphan linked list found./dev/mapper/debian--vg-root:unexpected inconsistency; RUN fsck manually.

(); returnSqlsession.selectlist ("Test.finduserbyid", id); }}Test class: PackageJUnit;ImportJava.io.InputStream;Importorg.apache.ibatis.io.Resources;Importorg.apache.ibatis.session.SqlSessionFactory;ImportOrg.apache.ibatis.session.SqlSessionFactoryBuilder;ImportOrg.junit.Before;Importorg.junit.Test;ImportDAO. Userdao;ImportDAO. Userdaoimpl;ImportPojo. User; Public classDaotest { Publicsqlsessionfactory sqlsessionfactory; @Before Public voidBefore ()throwsException {String resource= "Sqlmapconfi

Spring Mapper injection into service failed solution Background: Some time ago in the research Springboot, and the company's small projects successfully used Springboot transformation, for the springboot of the agreement than the concept of configuration, it is agreed that the project structure and code more concise and elegant. This time is not too busy, so the project is ready to change, now the project with the company's traditional SSM, the projec

Using only mapper without reduce can significantly reduce the time it takes for a mapreduce program to run.Sometimes the program writes data to multiple hbase tables.So there is a need for title.The code given below, not the code that can be run, just shows the necessary items to be set in the driver, the interfaces that the Mapper class needs to implement, the parameters that the map function needs, and ho