導讀
最近一段時間比較忙，以至於很久沒有更新Spring Boot系列文章，恰好最近用到Druid， 就將Spring Boot 使用 Druid作為數據源做一個簡單的介紹。
Druid介紹：
Druid是阿里巴巴開源的數據庫連接池，Druid號稱是Java語言中最好的數據庫連接池，並且能夠提供強大的監控和擴展功能，Druid的官方地址
了解更多：
JDBC連接池、監控組件 Druid （oschina）
快速上手：
下面來說明如何在 spring Boot 中配置使用Druid ，本例使用的持久層框為Spring Boot JPA。
第一步：添加pom依賴:
<dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-data-jpa</artifactId> </dependency> <dependency> <groupId>com.alibaba</groupId> <artifactId>druid</artifactId> <version>1.0.20</version> </dependency> 第二步：配置yml文件 數據源相關信息
spring: datasource: url: jdbc:mysql://localhost:3306/sanji-boot?useUnicode=true&characterEncoding=utf-8&useSSL=false username: root password: 123456 driver-class-name: com.mysql.jdbc.Driver platform: mysql type: com.alibaba.druid.pool.DruidDataSource # 下面為連接池的補充設置，應用到上面所有數據源中 # 初始化大小，最小，最大 initialSize: 1 minIdle: 3 maxActive: 20 # 配置獲取連接等待超時的時間 maxWait: 60000 # 配置間隔多久才進行一次檢測，檢測需要關閉的空閑連接，單位是毫秒 timeBetweenEvictionRunsMillis: 60000 # 配置一個連接在池中最小生存的時間，單位是毫秒 minEvictableIdleTimeMillis: 30000 validationQuery: select 'x' testWhileIdle: true testOnBorrow: false testOnReturn: false # 打開PSCache，並且指定每個連接上PSCache的大小 poolPreparedStatements: true maxPoolPreparedStatementPerConnectionSize: 20 # 配置監控統計攔截的filters，去掉后監控界面sql無法統計，'wall'用於防火牆 filters: stat,wall,slf4j # 通過connectProperties屬性來打開mergeSql功能；慢SQL記錄 connectionProperties: druid.stat.mergeSql=true;druid.stat.slowSqlMillis=5000 # 合並多個DruidDataSource的監控數據 #useGlobalDataSourceStat: true jpa: show-sql: true properties: hibernate: hbm2ddl: auto: create第三步：配置Druid的監控統計功能
這里有兩種方式 ：
第一種方式@Confing注解 配置類:
@Configuration public class DruidConfiguration { private static final Logger logger = LoggerFactory.getLogger(DruidConfiguration.class); private static final String DB_PREFIX = "spring.datasource"; @Bean public ServletRegistrationBean druidServlet() { logger.info("init Druid Servlet Configuration "); ServletRegistrationBean servletRegistrationBean = new ServletRegistrationBean(new StatViewServlet(), "/druid/*"); // IP白名單 servletRegistrationBean.addInitParameter("allow", "192.168.2.25,127.0.0.1"); // IP黑名單(共同存在時，deny優先於allow) servletRegistrationBean.addInitParameter("deny", "192.168.1.100"); //控制台管理用戶 servletRegistrationBean.addInitParameter("loginUsername", "admin"); servletRegistrationBean.addInitParameter("loginPassword", "admin"); //是否能夠重置數據 禁用HTML頁面上的“Reset All”功能 servletRegistrationBean.addInitParameter("resetEnable", "false"); return servletRegistrationBean; } @Bean public FilterRegistrationBean filterRegistrationBean() { FilterRegistrationBean filterRegistrationBean = new FilterRegistrationBean(new WebStatFilter()); filterRegistrationBean.addUrlPatterns("/*"); filterRegistrationBean.addInitParameter("exclusions", "*.js,*.gif,*.jpg,*.png,*.css,*.ico,/druid/*"); return filterRegistrationBean; } //解決 spring.datasource.filters=stat,wall,log4j 無法正常注冊進去 @ConfigurationProperties(prefix = DB_PREFIX) class IDataSourceProperties { private String url; private String username; private String password; private String driverClassName; private int initialSize; private int minIdle; private int maxActive; private int maxWait; private int timeBetweenEvictionRunsMillis; private int minEvictableIdleTimeMillis; private String validationQuery; private boolean testWhileIdle; private boolean testOnBorrow; private boolean testOnReturn; private boolean poolPreparedStatements; private int maxPoolPreparedStatementPerConnectionSize; private String filters; private String connectionProperties; @Bean //聲明其為Bean實例 @Primary //在同樣的DataSource中，首先使用被標注的DataSource public DataSource dataSource() { DruidDataSource datasource = new DruidDataSource(); datasource.setUrl(url); datasource.setUsername(username); datasource.setPassword(password); datasource.setDriverClassName(driverClassName); //configuration 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.setMaxPoolPreparedStatementPerConnectionSize(maxPoolPreparedStatementPerConnectionSize); try { datasource.setFilters(filters); } catch (SQLException e) { System.err.println("druid configuration initialization filter: " + e); } datasource.setConnectionProperties(connectionProperties); return datasource; } public String getUrl() { return url; } public void setUrl(String url) { this.url = url; } public String getUsername() { return username; } public void setUsername(String username) { this.username = username; } public String getPassword() { return password; } public void setPassword(String password) { this.password = password; } public String getDriverClassName() { return driverClassName; } public void setDriverClassName(String driverClassName) { this.driverClassName = driverClassName; } public int getInitialSize() { return initialSize; } public void setInitialSize(int initialSize) { this.initialSize = initialSize; } public int getMinIdle() { return minIdle; } public void setMinIdle(int minIdle) { this.minIdle = minIdle; } public int getMaxActive() { return maxActive; } public void setMaxActive(int maxActive) { this.maxActive = maxActive; } public int getMaxWait() { return maxWait; } public void setMaxWait(int maxWait) { this.maxWait = maxWait; } public int getTimeBetweenEvictionRunsMillis() { return timeBetweenEvictionRunsMillis; } public void setTimeBetweenEvictionRunsMillis(int timeBetweenEvictionRunsMillis) { this.timeBetweenEvictionRunsMillis = timeBetweenEvictionRunsMillis; } public int getMinEvictableIdleTimeMillis() { return minEvictableIdleTimeMillis; } public void setMinEvictableIdleTimeMillis(int minEvictableIdleTimeMillis) { this.minEvictableIdleTimeMillis = minEvictableIdleTimeMillis; } public String getValidationQuery() { return validationQuery; } public void setValidationQuery(String validationQuery) { this.validationQuery = validationQuery; } public boolean isTestWhileIdle() { return testWhileIdle; } public void setTestWhileIdle(boolean testWhileIdle) { this.testWhileIdle = testWhileIdle; } public boolean isTestOnBorrow() {