[Streaming][DOC] Fix typo & formatting for JavaDoc

sql/core/src/main/scala/org/apache/spark/sql/Column.scala

@@ -199,13 +199,13 @@ class Column(val expr: Expression) extends Logging {
   /**
    * Extracts a value or values from a complex type.
    * The following types of extraction are supported:
-   *
-   *  - Given an Array, an integer ordinal can be used to retrieve a single value.
-   *  - Given a Map, a key of the correct type can be used to retrieve an individual value.
-   *  - Given a Struct, a string fieldName can be used to extract that field.
-   *  - Given an Array of Structs, a string fieldName can be used to extract filed
-   *    of every struct in that array, and return an Array of fields
-   *
+   * <ul>
+   * <li>Given an Array, an integer ordinal can be used to retrieve a single value.</li>
+   * <li>Given a Map, a key of the correct type can be used to retrieve an individual value.</li>
+   * <li>Given a Struct, a string fieldName can be used to extract that field.</li>
+   * <li>Given an Array of Structs, a string fieldName can be used to extract filed
+   *    of every struct in that array, and return an Array of fields.</li>
+   * </ul>
    * @group expr_ops
    * @since 1.4.0
    */

sql/core/src/main/scala/org/apache/spark/sql/DataFrameWriter.scala

@@ -46,11 +46,13 @@ final class DataFrameWriter[T] private[sql](ds: Dataset[T]) {
   private val df = ds.toDF()
 
   /**
+   * <ul>
    * Specifies the behavior when data or table already exists. Options include:
-   *   - `SaveMode.Overwrite`: overwrite the existing data.
-   *   - `SaveMode.Append`: append the data.
-   *   - `SaveMode.Ignore`: ignore the operation (i.e. no-op).
-   *   - `SaveMode.ErrorIfExists`: default option, throw an exception at runtime.
+   * <li>`SaveMode.Overwrite`: overwrite the existing data.</li>
+   * <li>`SaveMode.Append`: append the data.</li>
+   * <li>`SaveMode.Ignore`: ignore the operation (i.e. no-op).</li>
+   * <li>`SaveMode.ErrorIfExists`: default option, throw an exception at runtime.</li>
+   * </ul>
    *
    * @since 1.4.0
    */
@@ -61,10 +63,12 @@ final class DataFrameWriter[T] private[sql](ds: Dataset[T]) {
 
   /**
    * Specifies the behavior when data or table already exists. Options include:
-   *   - `overwrite`: overwrite the existing data.
-   *   - `append`: append the data.
-   *   - `ignore`: ignore the operation (i.e. no-op).
-   *   - `error` or `errorifexists`: default option, throw an exception at runtime.
+   * <ul>
+   * <li>`overwrite`: overwrite the existing data.</li>
+   * <li>`append`: append the data.</li>
+   * <li>`ignore`: ignore the operation (i.e. no-op).</li>
+   * <li>`error` or `errorifexists`: default option, throw an exception at runtime.</li>
+   * </ul>
    *
    * @since 1.4.0
    */
@@ -164,8 +168,10 @@ final class DataFrameWriter[T] private[sql](ds: Dataset[T]) {
    * laid out on the file system similar to Hive's partitioning scheme. As an example, when we
    * partition a dataset by year and then month, the directory layout would look like:
    *
-   *   - year=2016/month=01/
-   *   - year=2016/month=02/
+   * <ul>
+   * <li>year=2016/month=01/</li>
+   * <li>year=2016/month=02/</li>
+   * </ul>
    *
    * Partitioning is one of the most widely used techniques to optimize physical data layout.
    * It provides a coarse-grained index for skipping unnecessary data reads when queries have

sql/core/src/main/scala/org/apache/spark/sql/ForeachWriter.scala

@@ -130,8 +130,11 @@ abstract class ForeachWriter[T] extends Serializable {
    * Called when stopping to process one partition of new data in the executor side. This is
    * guaranteed to be called either `open` returns `true` or `false`. However,
    * `close` won't be called in the following cases:
-   *  - JVM crashes without throwing a `Throwable`
-   *  - `open` throws a `Throwable`.
+   *
+   * <ul>
+   * <li>JVM crashes without throwing a `Throwable`</li>
+   * <li>`open` throws a `Throwable`.</li>
+   * </ul>
    *
    * @param errorOrNull the error thrown during processing data or null if there was no error.
    */

sql/core/src/main/scala/org/apache/spark/sql/SparkSessionExtensions.scala

@@ -30,12 +30,15 @@ import org.apache.spark.sql.catalyst.rules.Rule
  * regarding binary compatibility and source compatibility of methods here.
  *
  * This current provides the following extension points:
- * - Analyzer Rules.
- * - Check Analysis Rules
- * - Optimizer Rules.
- * - Planning Strategies.
- * - Customized Parser.
- * - (External) Catalog listeners.
+ *
+ * <ul>
+ * <li>Analyzer Rules.</li>
+ * <li>Check Analysis Rules.</li>
+ * <li>Optimizer Rules.</li>
+ * <li>Planning Strategies.</li>
+ * <li>Customized Parser.</li>
+ * <li>(External) Catalog listeners.</li>
+ * </ul>
  *
  * The extensions can be used by calling withExtension on the [[SparkSession.Builder]], for
  * example: