SpringBoot集成Druid連接池

關於數據庫連接池

• 早期數據庫訪問（也沒多少人上網）

  ​ 　①裝載數據庫驅動程序；

  　　②通過jdbc建立數據庫連接；

  　　③訪問數據庫，執行sql語句；

  　　④斷開數據庫連接。

  
  

  對於並發量大的網站，會導致以下問題：

  • 每一次web請求都要建立一次數據庫連接，在同樣的步驟下重復占用系統資源

  • 不能控制被創建的連接對象數，系統資源會被毫無顧及的分配出去

    如連接過多，也可能導致內存泄漏，服務器崩潰。

• 數據庫連接池

  連接池的作用是為了提高性能，將已經創建好的連接保存在池中，當有請求來時，直接使用已經創建好的連接對Server端進行訪問。

  這樣省略（復用）了創建連接和銷毀連接的過程（TCP連接建立時的三次握手和銷毀時的四次握手），從而在性能上得到了提高。

• 囂張的Druid（GitHub的Wiki上自稱是Java語言最好的數據庫連接池）

  

集成Druid

在上次Thymeleaf基礎上進行集成

https://www.cnblogs.com/noneplus/p/11528129.html

• 引入pom

<!-- https://mvnrepository.com/artifact/com.alibaba/druid -->
<dependency>
    <groupId>com.alibaba</groupId>
    <artifactId>druid</artifactId>
    <version>1.1.20</version>
</dependency>

• yaml

  spring:
    datasource:
      #   數據源基本配置
      username: noneplus
      password: Noneplus564925080!
      driver-class-name: com.mysql.cj.jdbc.Driver
      url: jdbc:mysql://47.103.6.247:3306/user?serverTimezone=UTC
      type: com.alibaba.druid.pool.DruidDataSource
      #   Druid數據源配置
      initialSize: 5
      minIdle: 5
      maxActive: 20
      maxWait: 60000
      timeBetweenEvictionRunsMillis: 60000
      minEvictableIdleTimeMillis: 300000
      validationQuery: SELECT 1 FROM DUAL
      testWhileIdle: true
      testOnBorrow: false
      testOnReturn: false
      poolPreparedStatements: true
      #   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,log4j
      maxPoolPreparedStatementPerConnectionSize: 20
      useGlobalDataSourceStat: true
      connectionProperties: druid.stat.mergeSql=true;druid.stat.slowSqlMillis=500
    thymeleaf:
      cache: false
  pagehelper:
    helperDialect: mysql
    reasonable: true
    supportMethodsArguments: true
    pageSizeZero: false #pageSize=0
  
  

• DruidConfig

  package zkrun.top.web.config;
  
  
  import com.alibaba.druid.pool.DruidDataSource;
  import com.alibaba.druid.support.http.StatViewServlet;
  import com.alibaba.druid.support.http.WebStatFilter;
  import org.springframework.boot.context.properties.ConfigurationProperties;
  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 javax.sql.DataSource;
  import java.util.Arrays;
  import java.util.HashMap;
  import java.util.Map;
  
  @Configuration
  public class DruidConfig {
  
      //加載application.yaml中的Druid配置
      @ConfigurationProperties(prefix = "spring.datasource")
      @Bean
      public DataSource druid(){
          return  new DruidDataSource();
      }
  
      //配置Druid的監控
      //1、配置一個管理后台的Servlet
      @Bean
      public ServletRegistrationBean statViewServlet(){
          ServletRegistrationBean bean = new ServletRegistrationBean(new StatViewServlet(), "/druid/*");
          Map<String,String> initParams = new HashMap<>();
  
          initParams.put("loginUsername","hq");
          initParams.put("loginPassword","564925080");
          initParams.put("allow","");//默認就是允許所有訪問
          initParams.put("deny","192.168.15.21");
  
          bean.setInitParameters(initParams);
          return bean;
      }
  
  
      //2、配置一個web監控的filter
      @Bean
      public FilterRegistrationBean webStatFilter(){
          FilterRegistrationBean bean = new FilterRegistrationBean();
          bean.setFilter(new WebStatFilter());
  
          Map<String,String> initParams = new HashMap<>();
          initParams.put("exclusions","*.js,*.css,/druid/*");
  
          bean.setInitParameters(initParams);
  
          bean.setUrlPatterns(Arrays.asList("/*"));
  
          return  bean;
      }
  }
  

• log4j

   <dependency>
              <groupId>log4j</groupId>
              <artifactId>log4j</artifactId>
              <version>1.2.17</version>
          </dependency>
  

測試

訪問：

http://localhost:8080/druid/

實時監控：

數據源配置文件密碼加密顯示

• 找到jar包，在終端打開：

• 生成密碼

java -cp druid-1.0.16.jar com.alibaba.druid.filter.config.ConfigTools yourPassword

其中druid-1.0.16.jar換成正在使用對應的版本，yourPassword改成數據庫連接的密碼。

生成privateKey和publicKey以及password

privateKey:MIIBVAIBADANBgkqhkiG9w0BAQEFAASCAT4wggE6AgEAAkEAgiX0+n2diIixWASA642qrI8hTo2xg1LItfeDFwGEg9G1wvlarF69gq+wDBpPhY63DDbry8d3I/vNZMaG0bGxwwIDAQABAkAQfiDiUWLSN4hJwCBaOVSkk2rEGp6hJq
96p8f79VxGm/FneqyzLgiIQvvIutsOWSSQses+C/cDoXYEgfddieSpAiEAuq1lcFuBPh7MWZwlbIi0GM4+/1tNQed+W9Lm3qGJYk0CIQCyepaXbrY8Vk8pUZMOKr74kFFBfG5WqbAJuNYym1PMTwIgZttPfx8METxLADzm6exQvzI0x+J4qQ1yNAn
6p0R+PCkCIFPZ8EI5C3kRe6OH5bT0NECHXQWNNjGVC1Wl90xTWW1VAiEAnKdXLI45e1e8jgpCQ4TG90PmDlKlrcxUnBiHUrOhyew=
publicKey:MFwwDQYJKoZIhvcNAQEBBQADSwAwSAJBAIIl9Pp9nYiIsVgEgOuNqqyPIU6NsYNSyLX3gxcBhIPRtcL5WqxevYKvsAwaT4WOtww268vHdyP7zWTGhtGxscMCAwEAAQ==
password:MEMMpYHaOUFVuaR37bMbUmGW76WVSLAD7pnFLrbup5H4Q6sZvWMDsYAcnZvAL2hY2Man1rc6SCJMYwrse1xPKw==

• yaml配置

修改password，添加公鑰。

spring:
  datasource:
    #   數據源基本配置
    username: noneplus
    password: MEMMpYHaOUFVuaR37bMbUmGW76WVSLAD7pnFLrbup5H4Q6sZvWMDsYAcnZvAL2hY2Man1rc6SCJMYwrse1xPKw==   # 1.配置生成的password
    driver-class-name: com.mysql.cj.jdbc.Driver
    url: jdbc:mysql://47.103.6.247:3306/user?serverTimezone=UTC
    type: com.alibaba.druid.pool.DruidDataSource
    #   Druid數據源配置
    initialSize: 5
    minIdle: 5
    maxActive: 20
    maxWait: 60000
    timeBetweenEvictionRunsMillis: 60000
    minEvictableIdleTimeMillis: 300000
    validationQuery: SELECT 1 FROM DUAL
    testWhileIdle: true
    testOnBorrow: false
    testOnReturn: false
    poolPreparedStatements: true
    #   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,log4j,config  # 3.添加config
    maxPoolPreparedStatementPerConnectionSize: 20
    useGlobalDataSourceStat: true
    # 2.開啟加密，配置公鑰
    connectionProperties: druid.stat.mergeSql=true;druid.stat.slowSqlMillis=500;config.decrypt=true;config.decrypt.key=MFwwDQYJKoZIhvcNAQEBBQADSwAwSAJBAIIl9Pp9nYiIsVgEgOuNqqyPIU6NsYNSyLX3gxcBhIPRtcL5WqxevYKvsAwaT4WOtww268vHdyP7zWTGhtGxscMCAwEAAQ==
  thymeleaf:
    cache: false
pagehelper:
  helperDialect: mysql
  reasonable: true
  supportMethodsArguments: true
  pageSizeZero: false #pageSize=0