1、JDBC
1.1、添加jdbc依赖
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-jdbc</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<scope>runtime</scope>
</dependency>
1.2、配置数据源
spring.datasource.url=jdbc:mysql:///springboot
spring.datasource.username=root
spring.datasource.password=admin
效果：
默认是使用org.apache.tomcat.jdbc.pool.DataSource作为数据源，而数据源的相关配置在DataSourceProperties类中。
1.3、自动配置原理：
1）、参考DataSourceConfiguration，根据配置创建数据源，默认使用Tomcat连接池，可以使用spring.datasource.type来指定自定义的数据源类型。
2）、SpringBoot默认支持以下数据库连接池：
-
org.apache.tomcat.jdbc.pool.DataSource
-
com.zaxxer.hikari.HikariDataSource
-
org.apache.commons.dbcp.BasicDataSource
-
org.apache.commons.dbcp2.BasicDataSource
3）、自定义数据源类型
@ConditionalOnMissingBean(DataSource.class) @ConditionalOnProperty(name = "spring.datasource.type") static class Generic { @Bean public DataSource dataSource(DataSourceProperties properties) { //使用DataSourceBuilder创建数据源，利用反射创建相应type的数据源，并且绑定相关属性 return properties.initializeDataSourceBuilder().build(); } }4）、DataSourceInitializer：ApplicationListener类型的监听器
class DataSourceInitializer implements ApplicationListener<DataSourceInitializedEvent> {
private final DataSourceProperties properties;
private final ApplicationContext applicationContext;
private DataSource dataSource;
private boolean initialized = false;
DataSourceInitializer(DataSourceProperties properties,
ApplicationContext applicationContext) {
this.properties = properties;
this.applicationContext = applicationContext;
}
@PostConstruct
public void init() {
//当DataSourceProperties初始化完成后
if (!this.properties.isInitialize()) {
logger.debug("Initialization disabled (not running DDL scripts)");
return;
}
if (this.applicationContext.getBeanNamesForType(DataSource.class, false,
false).length > 0) {
//获取DataSource的bean
this.dataSource = this.applicationContext.getBean(DataSource.class);
}
if (this.dataSource == null) {
logger.debug("No DataSource found so not initializing");
return;
}
//执行schema脚本
runSchemaScripts();
}
private void runSchemaScripts() {
//查看全局配置文件中是否有spring.datasource.schema
List<Resource> scripts = getScripts("spring.datasource.schema",
this.properties.getSchema(), "schema");
if (!scripts.isEmpty()) {
String username = this.properties.getSchemaUsername();
String password = this.properties.getSchemaPassword();
runScripts(scripts, username, password);
try {
this.applicationContext
.publishEvent(new DataSourceInitializedEvent(this.dataSource));
// The listener might not be registered yet, so don't rely on it.
if (!this.initialized) {
//执行数据插入脚本
runDataScripts();
this.initialized = true;
}
}
catch (IllegalStateException ex) {
logger.warn("Could not send event to complete DataSource initialization ("
+ ex.getMessage() + ")");
}
}
}
@Override
public void onApplicationEvent(DataSourceInitializedEvent event) {
if (!this.properties.isInitialize()) {
logger.debug("Initialization disabled (not running data scripts)");
return;
}
// NOTE the event can happen more than once and
// the event datasource is not used here
//如果初始化完成后，执行数据插入
if (!this.initialized) {
runDataScripts();
this.initialized = true;
}
}
private void runDataScripts() {
List<Resource> scripts = getScripts("spring.datasource.data",
this.properties.getData(), "data");
String username = this.properties.getDataUsername();
String password = this.properties.getDataPassword();
runScripts(scripts, username, password);
}
private List<Resource> getScripts(String propertyName, List<String> resources,
String fallback) {
if (resources != null) {
//如果配置了，则从指定的资源文件中加载脚本
return getResources(propertyName, resources, true);
}
//如果未配置，则使用classpath*:schema-all.sql或者classpath*：schema.sql作为脚本名，其中platform默认为all
String platform = this.properties.getPlatform();
List<String> fallbackResources = new ArrayList<String>();
fallbackResources.add("classpath*:" + fallback + "-" + platform + ".sql");
fallbackResources.add("classpath*:" + fallback + ".sql");
return getResources(propertyName, fallbackResources, false);
}
private List<Resource> getResources(String propertyName, List<String> locations,
boolean validate) {
List<Resource> resources = new ArrayList<Resource>();
for (String location : locations) {
for (Resource resource : doGetResources(location)) {
if (resource.exists()) {
resources.add(resource);
}
else if (validate) {
throw new ResourceNotFoundException(propertyName, resource);
}
}
}
return resources;
}
private Resource[] doGetResources(String location) {
try {
SortedResourcesFactoryBean factory = new SortedResourcesFactoryBean(
this.applicationContext, Collections.singletonList(location));
factory.afterPropertiesSet();
return factory.getObject();
}
catch (Exception ex) {
throw new IllegalStateException("Unable to load resources from " + location,
ex);
}
}
private void runScripts(List<Resource> resources, String username, String password) {
if (resources.isEmpty()) {
return;
}
ResourceDatabasePopulator populator = new ResourceDatabasePopulator();
populator.setContinueOnError(this.properties.isContinueOnError());
populator.setSeparator(this.properties.getSeparator());
if (this.properties.getSqlScriptEncoding() != null) {
populator.setSqlScriptEncoding(this.properties.getSqlScriptEncoding().name());
}
for (Resource resource : resources) {
populator.addScript(resource);
}
DataSource dataSource = this.dataSource;
if (StringUtils.hasText(username) && StringUtils.hasText(password)) {
dataSource = DataSourceBuilder.create(this.properties.getClassLoader())
.driverClassName(this.properties.determineDriverClassName())
.url(this.properties.determineUrl()).username(username)
.password(password).build();
}
DatabasePopulatorUtils.execute(populator, dataSource);
}
}
作用：
i）、runSchemaScripts();运行建表语句
ii）、runDataScripts();运行插入数据的sql语句
默认只需要将文件命名为：
schema-*.sql 用于建表操作
data-*.sql 用于数据操作
默认规则：schema.sql或者schema-all.sql
自定义规则：spring.datasource.schema=[classpath:department.sql]
2、使用Druid数据源
2.1、导入Druid数据源依赖
<!-- https://mvnrepository.com/artifact/com.alibaba/druid -->
<dependency>
<groupId>com.alibaba</groupId>
<artifactId>druid</artifactId>
<version>1.1.9</version>
</dependency>
2.2、Druid数据源配置
spring:
datasource:
url: jdbc:mysql:///springboot
username: root
password: admin
type: com.alibaba.druid.pool.DruidDataSource
initialSize: 5
minIdle: 5
maxActive: 20
2.3、Druid数据源配置类
@Configuration
public class DruidConfig {
@Bean
@ConfigurationProperties(prefix = "spring.datasource")
public DruidDataSource druid(){
return new DruidDataSource();
}
//配置Druid监控
//1、配置一个管理后台的Servlet
@Bean
public ServletRegistrationBean statViewServlet(){
ServletRegistrationBean bean = new ServletRegistrationBean(new StatViewServlet(), "/druid/*");
Map<String, String> initParams = new HashMap<>();
initParams.put("loginUsername", "admin");
initParams.put("loginPassword", "123456");
initParams.put("allow", "");//默认空串表示允许所有访问
// initParams.put("deny", "");
bean.setInitParameters(initParams);
return bean;
}
@Bean
public FilterRegistrationBean webStatFilter(){
FilterRegistrationBean bean = new FilterRegistrationBean();
bean.setFilter(new WebStatFilter());
Map<String, String> initParams = new HashMap<>();
initParams.put("exclusions", "*.js, *.css, *.png, *.jpg, *.gif, /druid/*");
bean.setInitParameters(initParams);
bean.setUrlPatterns(Arrays.asList("/*"));
return bean;
}
}
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