补充文档注释

src/main/java/xyz/zhouxy/jdbc/DefaultBeanRowMapper.java

@@ -35,9 +35,28 @@ import javax.annotation.Nullable;
 
 import com.google.common.base.CaseFormat;
 
+import xyz.zhouxy.plusone.commons.annotation.StaticFactoryMethod;
+
+/**
+ * DefaultBeanRowMapper
+ *
+ * <p>
+ * 默认实现的将 {@link ResultSet} 转换为 Java Bean 的 {@link RowMapper}。
+ * </p>
+ *
+ * <p>
+ * <b>NOTE: 使用反射获取类型信息，也是使用反射调用无参构造器和 {@code setter} 方法。
+ * 实际使用中还是建议针对目标类型自定义 {@link RowMapper}。</b>
+ * </p>
+ * @author <a href="http://zhouxy.xyz:3000/ZhouXY108">ZhouXY</a>
+ * @since 1.0.0
+ */
 public class DefaultBeanRowMapper<T> implements RowMapper<T> {
 
+    /** Bean 的无参构造器 */
     private final Constructor<T> constructor;
+
+    /** 列名到属性的映射 */
     private final Map<String, PropertyDescriptor> colPropertyMap;
 
     private DefaultBeanRowMapper(Constructor<T> constructor, Map<String, PropertyDescriptor> colPropertyMap) {
@@ -45,10 +64,29 @@ public class DefaultBeanRowMapper<T> implements RowMapper<T> {
         this.colPropertyMap = colPropertyMap;
     }
 
+    /**
+     * 创建一个 DefaultBeanRowMapper
+     *
+     * @param <T>      Bean 类型
+     * @param beanType Bean 类型
+     * @return DefaultBeanRowMapper 对象
+     * @throws SQLException 创建 DefaultBeanRowMapper 出现错误的异常时抛出
+     */
+    @StaticFactoryMethod(DefaultBeanRowMapper.class)
     public static <T> DefaultBeanRowMapper<T> of(Class<T> beanType) throws SQLException {
         return of(beanType, null);
     }
 
+    /**
+     * 创建一个 DefaultBeanRowMapper
+     *
+     * @param <T>            Bean 类型
+     * @param beanType       Bean 类型
+     * @param propertyColMap Bean 字段与列名的映射关系。key 是字段，value 是列名。
+     * @return DefaultBeanRowMapper 对象
+     * @throws SQLException 创建 DefaultBeanRowMapper 出现错误的异常时抛出
+     */
+    @StaticFactoryMethod(DefaultBeanRowMapper.class)
     public static <T> DefaultBeanRowMapper<T> of(Class<T> beanType, @Nullable Map<String, String> propertyColMap)
             throws SQLException {
         try {
@@ -60,6 +98,7 @@ public class DefaultBeanRowMapper<T> implements RowMapper<T> {
             BeanInfo beanInfo = Introspector.getBeanInfo(beanType);
             PropertyDescriptor[] propertyDescriptors = beanInfo.getPropertyDescriptors();
 
+            // Bean 的属性名为小驼峰，对应的列名为下划线
             Function<? super PropertyDescriptor, String> keyMapper;
             if (propertyColMap == null || propertyColMap.isEmpty()) {
                 keyMapper = p -> CaseFormat.LOWER_CAMEL.to(CaseFormat.LOWER_UNDERSCORE, p.getName());
@@ -84,13 +123,17 @@ public class DefaultBeanRowMapper<T> implements RowMapper<T> {
         }
     }
 
+    /** {@inheritDoc} */
     @Override
     public T mapRow(ResultSet rs, int rowNumber) throws SQLException {
         try {
+            // 调用无参构造器创建实例
             T newInstance = this.constructor.newInstance();
             ResultSetMetaData metaData = rs.getMetaData();
+            // 遍历结果的每一列
             for (int i = 1; i <= metaData.getColumnCount(); i++) {
                 String colName = metaData.getColumnName(i);
+                // 获取查询结果列名对应的属性，调用 setter
                 PropertyDescriptor propertyDescriptor = this.colPropertyMap.get(colName);
                 if (propertyDescriptor != null) {
                     Method setter = propertyDescriptor.getWriteMethod();