Mybitis根据工具类反射数据库生成映射+整合springboot
一 反向生成数据库mapper的工具类：
添加依赖
<dependency>
<groupId>org.mybatis.generator</groupId>
<artifactId>mybatis-generator-core</artifactId>
<scope>test</scope>
<version>1.3.2</version>
<optional>true</optional>
</dependency> <dependency>
<groupId>commons-io</groupId>
<artifactId>commons-io</artifactId>
<version>2.5</version>
</dependency> <dependency>
<groupId>org.apache.commons</groupId>
<artifactId>commons-lang3</artifactId>
<version>3.1</version>
</dependency>
工具类
package org.mybatis.generator.plugins; import org.mybatis.generator.api.IntrospectedTable;
import org.mybatis.generator.api.PluginAdapter;
import org.mybatis.generator.api.dom.java.*;
import org.mybatis.generator.api.dom.xml.Attribute;
import org.mybatis.generator.api.dom.xml.TextElement;
import org.mybatis.generator.api.dom.xml.XmlElement; import java.util.List; public class AddLimitOffsetPlugin extends PluginAdapter { public boolean validate(List<String> warnings) {
return true;
} public boolean modelExampleClassGenerated(TopLevelClass topLevelClass,
IntrospectedTable introspectedTable) {
FullyQualifiedJavaType offsetType = new FullyQualifiedJavaType(
"javax.annotation.Generated");
topLevelClass.addImportedType(offsetType);
topLevelClass.addAnnotation("@Generated(\"" + introspectedTable.getTableConfiguration().getTableName() + "\")");
PrimitiveTypeWrapper integerWrapper = FullyQualifiedJavaType.getIntInstance().getPrimitiveTypeWrapper(); Field limit = new Field();
limit.setName("limit");
limit.setVisibility(JavaVisibility.PRIVATE);
limit.setType(integerWrapper);
topLevelClass.addField(limit); Method limitSet = new Method();
limitSet.setVisibility(JavaVisibility.PUBLIC);
limitSet.setName("setLimit");
limitSet.addParameter(new Parameter(integerWrapper, "limit"));
limitSet.addBodyLine("this.limit = limit;");
topLevelClass.addMethod(limitSet); Method limitGet = new Method();
limitGet.setVisibility(JavaVisibility.PUBLIC);
limitGet.setReturnType(integerWrapper);
limitGet.setName("getLimit");
limitGet.addBodyLine("return limit;");
topLevelClass.addMethod(limitGet); Field offset = new Field();
offset.setName("offset");
offset.setVisibility(JavaVisibility.PRIVATE);
offset.setType(integerWrapper);
topLevelClass.addField(offset); Method offsetSet = new Method();
offsetSet.setVisibility(JavaVisibility.PUBLIC);
offsetSet.setName("setOffset");
offsetSet.addParameter(new Parameter(integerWrapper, "offset"));
offsetSet.addBodyLine("this.offset = offset;");
topLevelClass.addMethod(offsetSet); Method offsetGet = new Method();
offsetGet.setVisibility(JavaVisibility.PUBLIC);
offsetGet.setReturnType(integerWrapper);
offsetGet.setName("getOffset");
offsetGet.addBodyLine("return offset;");
topLevelClass.addMethod(offsetGet); return true;
} public boolean sqlMapSelectByExampleWithoutBLOBsElementGenerated(
XmlElement element, IntrospectedTable introspectedTable) {
XmlElement isNotNullElement = new XmlElement("if");
isNotNullElement.addAttribute(new Attribute("test", "limit > 0"));
isNotNullElement.addElement(new TextElement("limit ${limit}"));
element.getElements().add(isNotNullElement); isNotNullElement = new XmlElement("if");
isNotNullElement.addAttribute(new Attribute("test", "offset > 0"));
isNotNullElement.addElement(new TextElement("offset ${offset}"));
element.getElements().add(isNotNullElement);
return true;
} }
package org.mybatis.generator.plugins; import org.apache.commons.io.IOUtils;
import org.junit.Test;
import org.mybatis.generator.api.MyBatisGenerator;
import org.mybatis.generator.api.ProgressCallback;
import org.mybatis.generator.config.Configuration;
import org.mybatis.generator.config.Context;
import org.mybatis.generator.config.xml.ConfigurationParser;
import org.mybatis.generator.internal.DefaultShellCallback; import java.io.*;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import java.util.regex.Matcher;
import java.util.regex.Pattern; /**
* mybatis代码生成插件调用者.
*/
public class Generator { @Test
public void generate() throws Exception {
List<String> warnings = new ArrayList<String>();
boolean overwrite = true; InputStream stream = Generator.class.getClassLoader().getResourceAsStream("generatorConfig.xml"); ConfigurationParser cp = new ConfigurationParser(warnings);
InputStreamReader reader = new InputStreamReader(stream, "utf-8");
BufferedReader bufferedReader = new BufferedReader(reader); String line = bufferedReader.readLine();
StringBuffer buffer = new StringBuffer();
while (line != null) {
buffer.append(line + "\n");
line = bufferedReader.readLine();
}
String xmlWithParam = buffer.toString(); System.out.println("------- xml config begin -------");
System.out.println(xmlWithParam);
System.out.println("------- xml config end -------"); final Configuration config = cp.parseConfiguration(new ByteArrayInputStream(xmlWithParam.getBytes("utf-8")));
DefaultShellCallback callback = new DefaultShellCallback(overwrite);
MyBatisGenerator myBatisGenerator = new MyBatisGenerator(config, callback, warnings);
System.out.println("------- generator begin -------");
ProgressCallback cb = new ProgressCallback() {
private Pattern SqlProviderPattern = Pattern.compile("\\w*SqlProvider\\.java");
private List<String> taskNames = new ArrayList(); @Override
public void startTask(String taskName) {
/*
* 输出这些信息从而知道 生成那些类了
* Generating Example class for table demo
* Generating Primary Key class for table demo
* Generating Record class for table demo
* Generating Mapper Interface for table demo
* Generating SQL Provider for table demo
* Saving file DemoExample.java
* Saving file DemoKey.java Saving file Demo.java
* Saving file DemoMapper.java
* Saving file DemoSqlProvider.java
*/
// System.out.println(taskName);
taskNames.add( taskName);
} @Override
public void saveStarted(int arg0) {} @Override
public void introspectionStarted(int arg0) {} @Override
public void generationStarted(int arg0) {} @Override
public void done() {
for(String taskName : taskNames){
Matcher matcher = SqlProviderPattern.matcher(taskName);
if (matcher.find()) {
final String SqlProviderFilename = matcher.group();
System.out.println("处理生成文件,selectByExample 增加mysql分页: " + SqlProviderFilename);
List<Context> contexts = config.getContexts();
FilenameFilter filter = new FilenameFilter() {
@Override
public boolean accept(File dir, String name) {
return SqlProviderFilename.equalsIgnoreCase(name);
}
};
boolean done = false;
for (Context ctx : contexts) {
if(done){
break;
}
String targetProject = ctx.getJavaClientGeneratorConfiguration().getTargetProject();
String targetPackage = ctx.getJavaClientGeneratorConfiguration().getTargetPackage();
String dir = targetProject.replaceAll("\\.", "\\\\") + "\\" + targetPackage.replaceAll("\\.", "\\\\");
System.out.println(System.getProperty("user.dir") + dir);
File mapperDir = new File(System.getProperty("user.dir"), dir);
File[] files = mapperDir.listFiles(filter);
if (files != null && files.length > 0) {
File sqlProviderFile = files[0];
try {
Generator.addMysqlLimit(sqlProviderFile);
done = true;
} catch (Exception e) {
e.printStackTrace();
}
}
}
if(!done){
System.out.println("转换失败!!!! selectByExample 增加mysql分页: " + SqlProviderFilename);
} else {
System.out.println("转换成功!!!! selectByExample 增加mysql分页: " + SqlProviderFilename);
}
}
}
} @Override
public void checkCancel() throws InterruptedException {}
};
myBatisGenerator.generate(cb);
for (String warning : warnings) {
System.out.println(warning);
}
System.out.println("------- generator end -------");
// System.out.println(config.getClassPathEntries());
} private static void addMysqlLimit(File sqlProviderFile) throws Exception {
/*
* 这是自动生成的selectByExample 中的代码片段
if (example != null && example.getOrderByClause() != null) {
ORDER_BY(example.getOrderByClause()); // 整个文件唯一
} return SQL(); * 将return SQL()改为下面片段即可: String sqlString = SQL();
if (example != null && example.getLimit() != null) {
sqlString += " limit " + example.getLimit();
}
if (example != null && example.getOffset() != null) {
sqlString += " offset " + example.getOffset();
}
return sqlString;
*/
BufferedReader reader = new BufferedReader( new FileReader(sqlProviderFile));
List<String> lines = IOUtils.readLines(reader);
reader.close();
String limitString = " String sqlString = SQL();\n" +
" if (example != null && example.getLimit() != null) {\n" +
" sqlString += \" limit \" + example.getLimit();\n" +
" }\n" +
" if (example != null && example.getOffset() != null) {\n" +
" sqlString += \" offset \" + example.getOffset();\n" +
" }\n" +
" return sqlString;";
ArrayList<String> newLines = new ArrayList<String>(); for (int i=0; i< lines.size();++i) {
String line = lines.get(i);
newLines.add(line );
if(line.replaceAll(" ", "") .equalsIgnoreCase("ORDER_BY(example.getOrderByClause());")) {
// 添加下一行大括号和空白行
++i;
newLines.add(lines.get(i));
++i;
newLines.add(lines.get(i)); ++i; // 跳过 return SQL();
newLines.addAll(Arrays.asList( limitString.split("\n")));
}
} // for (String line : newLines) {
// System.out.println(line);
// }
FileOutputStream writer = new FileOutputStream(sqlProviderFile);
IOUtils.writeLines(newLines, "\n",writer,"UTF-8");
writer.close();
} public static void main(String[] args) throws Exception {
new Generator().generate();
}
}
映射关系配置xml
<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE generatorConfiguration PUBLIC "-//mybatis.org//DTD MyBatis Generator Configuration 1.0//EN" "http://mybatis.org/dtd/mybatis-generator-config_1_0.dtd" >
<generatorConfiguration> <context id="entmobile" targetRuntime="MyBatis3"> <plugin type="org.mybatis.generator.plugins.AddLimitOffsetPlugin" />
<plugin type="org.mybatis.generator.plugins.ToStringPlugin" /> <commentGenerator>
<property name="suppressDate" value="true" />
<!-- remove comments -->
<property name="suppressAllComments" value="true" />
</commentGenerator> <jdbcConnection driverClass="com.mysql.jdbc.Driver"
connectionURL="jdbc:mysql://localhost:3306/demo?useUnicode=true&characterEncoding=UTF-8&serverTimezone=UTC"
userId="root" password="root" /> <!-- java type resolver -->
<javaTypeResolver>
<property name="forceBigDecimals" value="false" />
</javaTypeResolver> <!-- gem entity -->
<!-- data -->
<javaModelGenerator targetPackage="com.自己建的实体类包.domain"
targetProject="./src/main/java">
<property name="enableSubPackages" value="true" />
<property name="trimStrings" value="false" />
</javaModelGenerator> <!-- //////////////////////////////////////////////////////////////////////////////////////////////////////////////// -->
<!-- gem annotated mapper -->
<!-- data -->
<javaClientGenerator type="ANNOTATEDMAPPER"
targetPackage="com.自己建的mapper包.mapper"
targetProject="./src/main/java">
<property name="enableSubPackages" value="true" />
</javaClientGenerator> <!--
<table tableName="material_type">
<generatedKey column="id" sqlStatement="JDBC"/>
</table>
--> <table tableName="表名">
<generatedKey column="id" sqlStatement="JDBC"/>
</table> </context>
</generatorConfiguration>
另外springboot启动类中添加注解：
@EnableAutoConfiguration
二 数据库配置 application.yml：
spring:
datasource:
url: jdbc:mysql://127.0.0.1:3306/demo?useUnicode=true&characterEncoding=UTF-8&zeroDateTimeBehavior=convertToNull&autoReconnect=true&connectTimeout=3000&socketTimeout=1000
username: root # 自己修改填写
password: root # 自己修改填写
type: com.alibaba.druid.pool.DruidDataSource
driver-class-name: com.mysql.jdbc.Driver
minIdle: 5
maxActive: 100
initialSize: 10
maxWait: 60000
timeBetweenEvictionRunsMillis: 60000
minEvictableIdleTimeMillis: 300000
validationQuery: select 'x'
testWhileIdle: true
testOnBorrow: false
testOnReturn: false
poolPreparedStatements: true
maxPoolPreparedStatementPerConnectionSize: 50
removeAbandoned: true
filters: stat # ,wall,log4j # 配置监控统计拦截的filters，去掉后监控界面sql无法统计，'wall'用于防火墙
connectionProperties: druid.stat.mergeSql=true;druid.stat.slowSqlMillis=5000 # 通过connectProperties属性来打开mergeSql功能；慢SQL记录
useGlobalDataSourceStat: true # 合并多个DruidDataSource的监控数据
druidLoginName: wjf # 登录druid的账号
druidPassword: wjf # 登录druid的密码
cachePrepStmts: true # 开启二级缓存
redis:
database: 0
host: XX.XX.XX.XX
port: 6380
password: 1234567
activemq:
broker-url: tcp://XX.XX.XX.XX:61616
user: admin
password: zhangjiawen
pool:
enabled: true
max-connections: 100
mybatis:
typeAliasesPackage: com.concurrent.mapper # 自己修改填写
mapperLocations: classpath:/com/concurrent/mapper/*.xml
mapperScanPackage: com.concurrent.mapper
configLocation: classpath:/mybatis-config.xml
mybatis-config.xml：
<?xml 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>
<settings>
<!-- 使全局的映射器启用或禁用缓存。 -->
<setting name="cacheEnabled" value="true" />
<!-- 全局启用或禁用延迟加载。当禁用时，所有关联对象都会即时加载。 -->
<setting name="lazyLoadingEnabled" value="true" />
<!-- 当启用时，有延迟加载属性的对象在被调用时将会完全加载任意属性。否则，每种属性将会按需要加载。 -->
<setting name="aggressiveLazyLoading" value="true"/>
<!-- 是否允许单条sql 返回多个数据集 (取决于驱动的兼容性) default:true -->
<setting name="multipleResultSetsEnabled" value="true" />
<!-- 是否可以使用列的别名 (取决于驱动的兼容性) default:true -->
<setting name="useColumnLabel" value="true" />
<!-- 允许JDBC 生成主键。需要驱动器支持。如果设为了true，这个设置将强制使用被生成的主键，有一些驱动器不兼容不过仍然可以执行。 default:false -->
<setting name="useGeneratedKeys" value="false" />
<!-- 指定 MyBatis 如何自动映射 数据基表的列 NONE：不隐射 PARTIAL:部分 FULL:全部 -->
<setting name="autoMappingBehavior" value="PARTIAL" />
<!-- 这是默认的执行类型 （SIMPLE: 简单； REUSE: 执行器可能重复使用prepared statements语句；BATCH: 执行器可以重复执行语句和批量更新） -->
<setting name="defaultExecutorType" value="SIMPLE" /> <setting name="defaultStatementTimeout" value="25" /> <setting name="defaultFetchSize" value="100" /> <setting name="safeRowBoundsEnabled" value="false" />
<!-- 使用驼峰命名法转换字段。 -->
<setting name="mapUnderscoreToCamelCase" value="true" />
<!-- 设置本地缓存范围 session:就会有数据的共享 statement:语句范围 (这样就不会有数据的共享 ) defalut:session -->
<setting name="localCacheScope" value="SESSION" />
<!-- 默认为OTHER,为了解决oracle插入null报错的问题要设置为NULL -->
<setting name="jdbcTypeForNull" value="NULL" />
<setting name="lazyLoadTriggerMethods" value="equals,clone,hashCode,toString" />
</settings> </configuration>
另外还有将mapper数据映射加入spring扫描
package com.concurrent.service; import com.alibaba.druid.pool.DruidDataSource;
import com.alibaba.druid.support.http.StatViewServlet;
import com.alibaba.druid.support.http.WebStatFilter;
import org.mybatis.spring.annotation.MapperScan;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.boot.web.servlet.FilterRegistrationBean;
import org.springframework.boot.web.servlet.ServletRegistrationBean;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Primary;
import org.springframework.session.data.redis.config.annotation.web.http.EnableRedisHttpSession; import javax.sql.DataSource;
import java.sql.SQLException; /**
* Created on 2016/10/25 0025.
*/ @Configuration
@MapperScan("com.自己建的映射包.mapper")
@EnableRedisHttpSession(maxInactiveIntervalInSeconds= 50)
public class DataSourceConfig {
private Logger logger = LoggerFactory.getLogger(DataSourceConfig.class); @Value("${spring.datasource.url}")
private String dbUrl; @Value("${spring.datasource.type}")
private String dbType; @Value("${spring.datasource.username}")
private String username; @Value("${spring.datasource.password}")
private String password; @Value("${spring.datasource.driver-class-name}")
private String driverClassName; @Value("${spring.datasource.initialSize}")
private int initialSize; @Value("${spring.datasource.minIdle}")
private int minIdle; @Value("${spring.datasource.maxActive}")
private int maxActive; @Value("${spring.datasource.maxWait}")
private int maxWait; @Value("${spring.datasource.timeBetweenEvictionRunsMillis}")
private int timeBetweenEvictionRunsMillis; @Value("${spring.datasource.minEvictableIdleTimeMillis}")
private int minEvictableIdleTimeMillis; @Value("${spring.datasource.validationQuery}")
private String validationQuery; @Value("${spring.datasource.testWhileIdle}")
private boolean testWhileIdle; @Value("${spring.datasource.testOnBorrow}")
private boolean testOnBorrow; @Value("${spring.datasource.testOnReturn}")
private boolean testOnReturn; @Value("${spring.datasource.poolPreparedStatements}")
private boolean poolPreparedStatements; @Value("${spring.datasource.filters}")
private String filters; @Value("${spring.datasource.connectionProperties}")
private String connectionProperties; @Value("${spring.datasource.useGlobalDataSourceStat}")
private boolean useGlobalDataSourceStat; @Value("${spring.datasource.druidLoginName}")
private String druidLoginName; @Value("${spring.datasource.druidPassword}")
private String druidPassword; @Bean(name="dataSource",destroyMethod = "close", initMethod="init")
@Primary //不要漏了这
public DataSource dataSource(){
DruidDataSource datasource = new DruidDataSource();
try {
datasource.setUrl(this.dbUrl);
datasource.setDbType(dbType);
datasource.setUsername(username);
datasource.setPassword(password);
datasource.setDriverClassName(driverClassName);
datasource.setInitialSize(initialSize);
datasource.setMinIdle(minIdle);
datasource.setMaxActive(maxActive);
datasource.setMaxWait(maxWait);
datasource.setTimeBetweenEvictionRunsMillis(timeBetweenEvictionRunsMillis);
datasource.setMinEvictableIdleTimeMillis(minEvictableIdleTimeMillis);
datasource.setValidationQuery(validationQuery);
datasource.setTestWhileIdle(testWhileIdle);
datasource.setTestOnBorrow(testOnBorrow);
datasource.setTestOnReturn(testOnReturn);
datasource.setPoolPreparedStatements(poolPreparedStatements);
datasource.setFilters(filters);
} catch (SQLException e) {
logger.error("druid configuration initialization filter", e);
}
return datasource;
} ///////// 下面是druid 监控访问的设置 /////////////////
@Bean
public ServletRegistrationBean druidServlet() {
ServletRegistrationBean reg = new ServletRegistrationBean();
reg.setServlet(new StatViewServlet());
reg.addUrlMappings("/druid/*"); //url 匹配
reg.addInitParameter("allow", "192.168.16.110,127.0.0.1"); // IP白名单 (没有配置或者为空，则允许所有访问)
reg.addInitParameter("deny", "192.168.16.111"); //IP黑名单 (存在共同时，deny优先于allow)
reg.addInitParameter("loginUsername", this.druidLoginName);//登录名
reg.addInitParameter("loginPassword", this.druidPassword);//登录密码
reg.addInitParameter("resetEnable", "false"); // 禁用HTML页面上的“Reset All”功能
return reg;
} @Bean(name="druidWebStatFilter")
public FilterRegistrationBean filterRegistrationBean() {
FilterRegistrationBean filterRegistrationBean = new FilterRegistrationBean();
filterRegistrationBean.setFilter(new WebStatFilter());
filterRegistrationBean.addUrlPatterns("/*");
filterRegistrationBean.addInitParameter("exclusions", "*.js,*.gif,*.jpg,*.png,*.css,*.ico,/druid/*"); //忽略资源
filterRegistrationBean.addInitParameter("profileEnable", "true");
filterRegistrationBean.addInitParameter("principalCookieName", "USER_COOKIE");
filterRegistrationBean.addInitParameter("principalSessionName", "USER_SESSION");
return filterRegistrationBean;
}
}
使用例子：
@Resource
private SysUserMapper sysUserMapper; private BloomFilter<Integer> bf; /***
* PostConstruct 程序启动时候加载此方法
*/
@PostConstruct
public void initBloomFilter() {
SysUserExample sysUserExample = new SysUserExample();
List<SysUser> sysUserList = sysUserMapper.selectByExample(sysUserExample); }
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