資訊專欄INFORMATION COLUMN
摘要：配置測(cè)試描述測(cè)試類技術(shù)部查詢表至此初步配置完成執(zhí)行過(guò)程獲取解析成接收方法方法方法屬性定位方法數(shù)據(jù)綁定到具體方法提交傳輸獲取配置解析標(biāo)簽對(duì)象獲取過(guò)程源碼使用
MyBatis 配置
4.0.0 com.huifer mybatisBook 1.0-SNAPSHOT UTF-8 UTF-8 1.8 org.mybatis mybatis 3.5.0 mysql mysql-connector-java 8.0.13 org.projectlombok lombok 1.18.4 true org.apache.maven.plugins maven-compiler-plugin 1.8 1.8
mybatis-config.xml
測(cè)試
DeptMapper.xml
INSERT INTO dept (dname, loc) VALUES (#{dname} , #{loc});
Dept.java
package com.huifer.mybatis;
import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;
/**
* 描述:
*
* @author huifer
* @date 2019-02-21
*/
@Data
@AllArgsConstructor
@NoArgsConstructor
public class Dept {
private Long id;
private String dname;
private String loc;
}
測(cè)試類
public class Demo {
public static void main(String[] args) throws Exception {
Dept dept = new Dept();
dept.setDname("技術(shù)部");
dept.setLoc("oc");
InputStream is = Resources.getResourceAsStream("mybatis-config.xml");
SqlSessionFactory factory = new SqlSessionFactoryBuilder().build(is);
SqlSession session = factory.openSession();
session.insert("insertDept", dept);
session.commit();
session.close();
}
}
查詢表
至此初步配置完成
執(zhí)行過(guò)程graph TD
start[獲取mybatis.config.xml] --> conditionA[SqlSessionFactory]
conditionA --> |xml 解析成 org.apache.ibatis.session.Configuration | conditionB[接收SqlSessionFactory]
conditionB --> |org.apache.ibatis.session.defaults.DefaultSqlSessionFactory.openSessionFromDataSource| conditionC[ SqlSession]
conditionC --> |org.apache.ibatis.session.defaults.DefaultSqlSession insert方法 update方法| conditionD[insert方法]
conditionD --> | org.apache.ibatis.mapping.MappedStatement sqlSource屬性 | conditionE[mapper 定位]
conditionE --> | org.apache.ibatis.executor.SimpleExecutor doUpdate方法 stmt|conditionF[數(shù)據(jù)綁定到具體sql]
conditionF --> |org.apache.ibatis.executor.statement.PreparedStatementHandler update方法 提交| conditionG[傳輸sql]
conditionG -->|commit| stop
session
獲取mybatils-config.xml 配置 解析xml標(biāo)簽
org.apache.ibatis.session.defaults.DefaultSqlSessionFactory
private SqlSession openSessionFromDataSource(ExecutorType execType, TransactionIsolationLevel level, boolean autoCommit) {
Transaction tx = null;
DefaultSqlSession var8;
try {
Environment environment = this.configuration.getEnvironment();
TransactionFactory transactionFactory = this.getTransactionFactoryFromEnvironment(environment);
tx = transactionFactory.newTransaction(environment.getDataSource(), level, autoCommit);
Executor executor = this.configuration.newExecutor(tx, execType);
var8 = new DefaultSqlSession(this.configuration, executor, autoCommit);
} catch (Exception var12) {
this.closeTransaction(tx);
throw ExceptionFactory.wrapException("Error opening session. Cause: " + var12, var12);
} finally {
ErrorContext.instance().reset();
}
return var8;
}
insert
org.apache.ibatis.session.defaults.DefaultSqlSession
public int insert(String statement, Object parameter) {
return this.update(statement, parameter);
}
public int update(String statement, Object parameter) {
int var4;
try {
this.dirty = true;
MappedStatement ms = this.configuration.getMappedStatement(statement);
var4 = this.executor.update(ms, this.wrapCollection(parameter));
} catch (Exception var8) {
throw ExceptionFactory.wrapException("Error updating database. Cause: " + var8, var8);
} finally {
ErrorContext.instance().reset();
}
return var4;
}
ms 對(duì)象
doUpdateorg.apache.ibatis.executor.SimpleExecutor
public int doUpdate(MappedStatement ms, Object parameter) throws SQLException {
Statement stmt = null;
int var6;
try {
Configuration configuration = ms.getConfiguration();
StatementHandler handler = configuration.newStatementHandler(this, ms, parameter, RowBounds.DEFAULT, (ResultHandler)null, (BoundSql)null);
stmt = this.prepareStatement(handler, ms.getStatementLog());
var6 = handler.update(stmt);
} finally {
this.closeStatement(stmt);
}
return var6;
}
update
org.apache.ibatis.executor.statement.PreparedStatementHandler
public int update(Statement statement) throws SQLException {
PreparedStatement ps = (PreparedStatement)statement;
ps.execute();
int rows = ps.getUpdateCount();
Object parameterObject = this.boundSql.getParameterObject();
KeyGenerator keyGenerator = this.mappedStatement.getKeyGenerator();
keyGenerator.processAfter(this.executor, this.mappedStatement, ps, parameterObject);
return rows;
}
Mapper
獲取過(guò)程源碼
org.apache.ibatis.builder.xml.XMLConfigBuilder 使用parseConfiguration 方法將 mybatis-config.xml 中的mappers 標(biāo)簽內(nèi)容獲取到 mapperElement具體執(zhí)行獲取內(nèi)容 ，作用將mappers添加到configuration 中
private void parseConfiguration(XNode root) {
try {
this.propertiesElement(root.evalNode("properties"));
Properties settings = this.settingsAsProperties(root.evalNode("settings"));
this.loadCustomVfs(settings);
this.loadCustomLogImpl(settings);
this.typeAliasesElement(root.evalNode("typeAliases"));
this.pluginElement(root.evalNode("plugins"));
this.objectFactoryElement(root.evalNode("objectFactory"));
this.objectWrapperFactoryElement(root.evalNode("objectWrapperFactory"));
this.reflectorFactoryElement(root.evalNode("reflectorFactory"));
this.settingsElement(settings);
this.environmentsElement(root.evalNode("environments"));
this.databaseIdProviderElement(root.evalNode("databaseIdProvider"));
this.typeHandlerElement(root.evalNode("typeHandlers"));
this.mapperElement(root.evalNode("mappers"));
} catch (Exception var3) {
throw new BuilderException("Error parsing SQL Mapper Configuration. Cause: " + var3, var3);
}
}
private void mapperElement(XNode parent) throws Exception {
if (parent != null) {
Iterator var2 = parent.getChildren().iterator();
while(true) {
while(var2.hasNext()) {
XNode child = (XNode)var2.next();
String resource;
if ("package".equals(child.getName())) {
resource = child.getStringAttribute("name");
this.configuration.addMappers(resource);
} else {
resource = child.getStringAttribute("resource");
String url = child.getStringAttribute("url");
String mapperClass = child.getStringAttribute("class");
XMLMapperBuilder mapperParser;
InputStream inputStream;
if (resource != null && url == null && mapperClass == null) {
ErrorContext.instance().resource(resource);
inputStream = Resources.getResourceAsStream(resource);
mapperParser = new XMLMapperBuilder(inputStream, this.configuration, resource, this.configuration.getSqlFragments());
mapperParser.parse();
} else if (resource == null && url != null && mapperClass == null) {
ErrorContext.instance().resource(url);
inputStream = Resources.getUrlAsStream(url);
mapperParser = new XMLMapperBuilder(inputStream, this.configuration, url, this.configuration.getSqlFragments());
mapperParser.parse();
} else {
if (resource != null || url != null || mapperClass == null) {
throw new BuilderException("A mapper element may only specify a url, resource or class, but not more than one.");
}
Class mapperInterface = Resources.classForName(mapperClass);
this.configuration.addMapper(mapperInterface);
}
}
}
return;
}
}
}
當(dāng)前Configuration 下的mappedStatements 屬性
org.apache.ibatis.binding.MapperRegistry addMapper 方法，作用將解析到的接口對(duì)象放到configuration 中 ，一個(gè)接口只能注冊(cè)一次
public void addMapper(Class type) {
if (type.isInterface()) {
if (this.hasMapper(type)) {
throw new BindingException("Type " + type + " is already known to the MapperRegistry.");
}
boolean loadCompleted = false;
try {
this.knownMappers.put(type, new MapperProxyFactory(type));
MapperAnnotationBuilder parser = new MapperAnnotationBuilder(this.config, type);
parser.parse();
loadCompleted = true;
} finally {
if (!loadCompleted) {
this.knownMappers.remove(type);
}
}
}
}
org.apache.ibatis.builder.annotation.MapperAnnotationBuilder parse方法
loadXmlResource 來(lái)確認(rèn)加載具體的xml文件
public void parse() {
String resource = this.type.toString();
if (!this.configuration.isResourceLoaded(resource)) {
this.loadXmlResource();
this.configuration.addLoadedResource(resource);
this.assistant.setCurrentNamespace(this.type.getName());
this.parseCache();
this.parseCacheRef();
Method[] methods = this.type.getMethods();
Method[] var3 = methods;
int var4 = methods.length;
for(int var5 = 0; var5 < var4; ++var5) {
Method method = var3[var5];
try {
if (!method.isBridge()) {
this.parseStatement(method);
}
} catch (IncompleteElementException var8) {
this.configuration.addIncompleteMethod(new MethodResolver(this, method));
}
}
}
this.parsePendingMethods();
}
private void loadXmlResource() {
if (!this.configuration.isResourceLoaded("namespace:" + this.type.getName())) {
String xmlResource = this.type.getName().replace(".", "/") + ".xml";
InputStream inputStream = this.type.getResourceAsStream("/" + xmlResource);
if (inputStream == null) {
try {
inputStream = Resources.getResourceAsStream(this.type.getClassLoader(), xmlResource);
} catch (IOException var4) {
}
}
if (inputStream != null) {
XMLMapperBuilder xmlParser = new XMLMapperBuilder(inputStream, this.assistant.getConfiguration(), xmlResource, this.configuration.getSqlFragments(), this.type.getName());
xmlParser.parse();
}
}
}
根據(jù) loadXmlResource 中下面這行得知 ， PojoMapper.xml 要和 PojoMapperInterface 放在一個(gè)路徑下
String xmlResource = this.type.getName().replace(".", "/") + ".xml";
具體sql
org.apache.ibatis.builder.xml.XMLStatementBuilder parseStatementNode 方法解析sql語(yǔ)句
public void parseStatementNode() {
String id = this.context.getStringAttribute("id");
String databaseId = this.context.getStringAttribute("databaseId");
if (this.databaseIdMatchesCurrent(id, databaseId, this.requiredDatabaseId)) {
Integer fetchSize = this.context.getIntAttribute("fetchSize");
Integer timeout = this.context.getIntAttribute("timeout");
String parameterMap = this.context.getStringAttribute("parameterMap");
String parameterType = this.context.getStringAttribute("parameterType");
Class parameterTypeClass = this.resolveClass(parameterType);
String resultMap = this.context.getStringAttribute("resultMap");
String resultType = this.context.getStringAttribute("resultType");
String lang = this.context.getStringAttribute("lang");
LanguageDriver langDriver = this.getLanguageDriver(lang);
Class resultTypeClass = this.resolveClass(resultType);
String resultSetType = this.context.getStringAttribute("resultSetType");
StatementType statementType = StatementType.valueOf(this.context.getStringAttribute("statementType", StatementType.PREPARED.toString()));
ResultSetType resultSetTypeEnum = this.resolveResultSetType(resultSetType);
String nodeName = this.context.getNode().getNodeName();
SqlCommandType sqlCommandType = SqlCommandType.valueOf(nodeName.toUpperCase(Locale.ENGLISH));
boolean isSelect = sqlCommandType == SqlCommandType.SELECT;
boolean flushCache = this.context.getBooleanAttribute("flushCache", !isSelect);
boolean useCache = this.context.getBooleanAttribute("useCache", isSelect);
boolean resultOrdered = this.context.getBooleanAttribute("resultOrdered", false);
XMLIncludeTransformer includeParser = new XMLIncludeTransformer(this.configuration, this.builderAssistant);
includeParser.applyIncludes(this.context.getNode());
this.processSelectKeyNodes(id, parameterTypeClass, langDriver);
SqlSource sqlSource = langDriver.createSqlSource(this.configuration, this.context, parameterTypeClass);
String resultSets = this.context.getStringAttribute("resultSets");
String keyProperty = this.context.getStringAttribute("keyProperty");
String keyColumn = this.context.getStringAttribute("keyColumn");
String keyStatementId = id + "!selectKey";
keyStatementId = this.builderAssistant.applyCurrentNamespace(keyStatementId, true);
Object keyGenerator;
if (this.configuration.hasKeyGenerator(keyStatementId)) {
keyGenerator = this.configuration.getKeyGenerator(keyStatementId);
} else {
keyGenerator = this.context.getBooleanAttribute("useGeneratedKeys", this.configuration.isUseGeneratedKeys() && SqlCommandType.INSERT.equals(sqlCommandType)) ? Jdbc3KeyGenerator.INSTANCE : NoKeyGenerator.INSTANCE;
}
this.builderAssistant.addMappedStatement(id, sqlSource, statementType, sqlCommandType, fetchSize, timeout, parameterMap, parameterTypeClass, resultMap, resultTypeClass, resultSetTypeEnum, flushCache, useCache, resultOrdered, (KeyGenerator)keyGenerator, keyProperty, keyColumn, databaseId, langDriver, resultSets);
}
}
還原sql方法
SqlSource sqlSource = langDriver.createSqlSource(this.configuration, this.context, parameterTypeClass);
org.apache.ibatis.scripting.defaults.RawSqlSource RawSqlSource方法
public RawSqlSource(Configuration configuration, String sql, Class parameterType) {
SqlSourceBuilder sqlSourceParser = new SqlSourceBuilder(configuration);
Class clazz = parameterType == null ? Object.class : parameterType;
this.sqlSource = sqlSourceParser.parse(sql, clazz, new HashMap());
}
org.apache.ibatis.builder.SqlSourceBuilder parse方法還原成sql語(yǔ)句
