chore：完善DruidConfig的代码说明，以及对异常忽略处添加ignored关键字

ruoyi-framework/src/main/java/com/ruoyi/framework/config/DruidConfig.java

@@ -1,20 +1,5 @@
 package com.ruoyi.framework.config;
 
-import java.io.IOException;
-import java.util.HashMap;
-import java.util.Map;
-import javax.servlet.Filter;
-import javax.servlet.FilterChain;
-import javax.servlet.ServletException;
-import javax.servlet.ServletRequest;
-import javax.servlet.ServletResponse;
-import javax.sql.DataSource;
-import org.springframework.boot.autoconfigure.condition.ConditionalOnProperty;
-import org.springframework.boot.context.properties.ConfigurationProperties;
-import org.springframework.boot.web.servlet.FilterRegistrationBean;
-import org.springframework.context.annotation.Bean;
-import org.springframework.context.annotation.Configuration;
-import org.springframework.context.annotation.Primary;
 import com.alibaba.druid.pool.DruidDataSource;
 import com.alibaba.druid.spring.boot.autoconfigure.DruidDataSourceBuilder;
 import com.alibaba.druid.spring.boot.autoconfigure.properties.DruidStatProperties;
@@ -23,19 +8,29 @@ import com.ruoyi.common.enums.DataSourceType;
 import com.ruoyi.common.utils.spring.SpringUtils;
 import com.ruoyi.framework.config.properties.DruidProperties;
 import com.ruoyi.framework.datasource.DynamicDataSource;
+import org.springframework.boot.autoconfigure.condition.ConditionalOnProperty;
+import org.springframework.boot.context.properties.ConfigurationProperties;
+import org.springframework.boot.web.servlet.FilterRegistrationBean;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.context.annotation.Primary;
+
+import javax.servlet.*;
+import javax.sql.DataSource;
+import java.io.IOException;
+import java.util.HashMap;
+import java.util.Map;
 
 /**
  * druid 配置多数据源
- * 
+ *
  * @author ruoyi
  */
 @Configuration
-public class DruidConfig
-{
+public class DruidConfig {
     @Bean
     @ConfigurationProperties("spring.datasource.druid.master")
-    public DataSource masterDataSource(DruidProperties druidProperties)
-    {
+    public DataSource masterDataSource(DruidProperties druidProperties) {
         DruidDataSource dataSource = DruidDataSourceBuilder.create().build();
         return druidProperties.dataSource(dataSource);
     }
@@ -43,16 +38,14 @@ public class DruidConfig
     @Bean
     @ConfigurationProperties("spring.datasource.druid.slave")
     @ConditionalOnProperty(prefix = "spring.datasource.druid.slave", name = "enabled", havingValue = "true")
-    public DataSource slaveDataSource(DruidProperties druidProperties)
-    {
+    public DataSource slaveDataSource(DruidProperties druidProperties) {
         DruidDataSource dataSource = DruidDataSourceBuilder.create().build();
         return druidProperties.dataSource(dataSource);
     }
 
     @Bean(name = "dynamicDataSource")
     @Primary
-    public DynamicDataSource dataSource(DataSource masterDataSource)
-    {
+    public DynamicDataSource dataSource(DataSource masterDataSource) {
         Map<Object, Object> targetDataSources = new HashMap<>();
         targetDataSources.put(DataSourceType.MASTER.name(), masterDataSource);
         setDataSource(targetDataSources, DataSourceType.SLAVE.name(), "slaveDataSource");
@@ -61,31 +54,27 @@ public class DruidConfig
 
     /**
      * 设置数据源
-     * 
+     *
      * @param targetDataSources 备选数据源集合
-     * @param sourceName 数据源名称
-     * @param beanName bean名称
+     * @param sourceName        数据源名称
+     * @param beanName          bean名称
      */
-    public void setDataSource(Map<Object, Object> targetDataSources, String sourceName, String beanName)
-    {
-        try
-        {
+    public void setDataSource(Map<Object, Object> targetDataSources, String sourceName, String beanName) {
+        try {
             DataSource dataSource = SpringUtils.getBean(beanName);
             targetDataSources.put(sourceName, dataSource);
-        }
-        catch (Exception e)
-        {
+        } catch (Exception ignored) {
+            //忽略此处的异常
         }
     }
 
     /**
      * 去除监控页面底部的广告
      */
-    @SuppressWarnings({ "rawtypes", "unchecked" })
+    @SuppressWarnings({"rawtypes", "unchecked"})
     @Bean
     @ConditionalOnProperty(name = "spring.datasource.druid.statViewServlet.enabled", havingValue = "true")
-    public FilterRegistrationBean removeDruidFilterRegistrationBean(DruidStatProperties properties)
-    {
+    public FilterRegistrationBean removeDruidFilterRegistrationBean(DruidStatProperties properties) {
         // 获取web监控页面的参数
         DruidStatProperties.StatViewServlet config = properties.getStatViewServlet();
         // 提取common.js的配置路径
@@ -93,17 +82,17 @@ public class DruidConfig
         String commonJsPattern = pattern.replaceAll("\\*", "js/common.js");
         final String filePath = "support/http/resources/js/common.js";
         // 创建filter进行过滤
-        Filter filter = new Filter()
-        {
+        Filter filter = new Filter() {
             @Override
-            public void init(javax.servlet.FilterConfig filterConfig) throws ServletException
-            {
+            public void init(javax.servlet.FilterConfig filterConfig) throws ServletException {
+                //web应用启动时，web服务器将创建Filter的实例对象，并调用init方法，读取web.xml的配置，完成对象的初始化功能
+                //filter对象只会创建一次，init方法也只会执行一次
+                //开发人员通过init的参数，可或得代表当前filter配置信息的FilterConfig对象
             }
 
             @Override
             public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain)
-                    throws IOException, ServletException
-            {
+                    throws IOException, ServletException {
                 chain.doFilter(request, response);
                 // 重置缓冲区，响应头不会被重置
                 response.resetBuffer();
@@ -116,8 +105,9 @@ public class DruidConfig
             }
 
             @Override
-            public void destroy()
-            {
+            public void destroy() {
+                //filter创建后会保存在内存中，当web应用移除或者服务器停止时才销毁
+                //该方法在Filter的生命周期中仅执行一次，在这个方法中，可以释放过滤器使用的资源
             }
         };
         FilterRegistrationBean registrationBean = new FilterRegistrationBean();