Make it clear that bean and immutable table schemas are moderately expensive to create.

services-custom/dynamodb-enhanced/src/main/java/software/amazon/awssdk/enhanced/dynamodb/TableSchema.java

@@ -39,6 +39,7 @@ public interface TableSchema<T> {
     /**
      * Returns a builder for the {@link StaticTableSchema} implementation of this interface which allows all attributes,
      * tags and table structure to be directly declared in the builder.
+     *
      * @param itemClass The class of the item this {@link TableSchema} will map records to.
      * @param <T> The type of the item this {@link TableSchema} will map records to.
      * @return A newly initialized {@link StaticTableSchema.Builder}.
@@ -50,6 +51,7 @@ static <T> StaticTableSchema.Builder<T> builder(Class<T> itemClass) {
     /**
      * Returns a builder for the {@link StaticImmutableTableSchema} implementation of this interface which allows all
      * attributes, tags and table structure to be directly declared in the builder.
+     *
      * @param immutableItemClass The class of the immutable item this {@link TableSchema} will map records to.
      * @param immutableBuilderClass The class that can be used to construct immutable items this {@link TableSchema}
      *                              maps records to.
@@ -66,6 +68,10 @@ static <T, B> StaticImmutableTableSchema.Builder<T, B> builder(Class<T> immutabl
      * Scans a bean class that has been annotated with DynamoDb bean annotations and then returns a
      * {@link BeanTableSchema} implementation of this interface that can map records to and from items of that bean
      * class.
+     *
+     * Creating a {@link BeanTableSchema} is a moderately expensive operation, and should be performed sparingly. This is
+     * usually done once at application startup.
+     *
      * @param beanClass The bean class this {@link TableSchema} will map records to.
      * @param <T> The type of the item this {@link TableSchema} will map records to.
      * @return An initialized {@link BeanTableSchema}.
@@ -79,6 +85,9 @@ static <T> BeanTableSchema<T> fromBean(Class<T> beanClass) {
      * {@link ImmutableTableSchema} implementation of this interface that can map records to and from items of that
      * immutable class.
      *
+     * Creating a {@link ImmutableTableSchema} is a moderately expensive operation, and should be performed sparingly. This is
+     * usually done once at application startup.
+     *
      * @param immutableClass The immutable class this {@link TableSchema} will map records to.
      * @param <T> The type of the item this {@link TableSchema} will map records to.
      * @return An initialized {@link ImmutableTableSchema}.
@@ -95,6 +104,9 @@ static <T> ImmutableTableSchema<T> fromImmutableClass(Class<T> immutableClass) {
      * {@link software.amazon.awssdk.enhanced.dynamodb.mapper.annotations.DynamoDbBean}<br>
      * {@link software.amazon.awssdk.enhanced.dynamodb.mapper.annotations.DynamoDbImmutable}
      *
+     * This is a moderately expensive operation, and should be performed sparingly. This is usually done once at
+     * application startup.
+     *
      * @param annotatedClass A class that has been annotated with DynamoDb enhanced client annotations.
      * @param <T> The type of the item this {@link TableSchema} will map records to.
      * @return An initialized {@link TableSchema}

services-custom/dynamodb-enhanced/src/main/java/software/amazon/awssdk/enhanced/dynamodb/mapper/BeanTableSchema.java

@@ -88,6 +88,9 @@
  *
  * </pre>
  *
+ * Creating an {@link BeanTableSchema} is a moderately expensive operation, and should be performed sparingly. This is
+ * usually done once at application startup.
+ *
  * @param <T> The type of object that this {@link TableSchema} maps to.
  */
 @SdkPublicApi
@@ -101,6 +104,10 @@ private BeanTableSchema(StaticTableSchema<T> staticTableSchema) {
     /**
      * Scans a bean class and builds a {@link BeanTableSchema} from it that can be used with the
      * {@link DynamoDbEnhancedClient}.
+     *
+     * Creating an {@link BeanTableSchema} is a moderately expensive operation, and should be performed sparingly. This is
+     * usually done once at application startup.
+     *
      * @param beanClass The bean class to build the table schema from.
      * @param <T> The bean class type.
      * @return An initialized {@link BeanTableSchema}

services-custom/dynamodb-enhanced/src/main/java/software/amazon/awssdk/enhanced/dynamodb/mapper/ImmutableTableSchema.java

@@ -86,8 +86,11 @@
  *         public Customer build() { ... };
  *     }
  * }
- *
  * </pre>
+ *
+ * Creating an {@link ImmutableTableSchema} is a moderately expensive operation, and should be performed sparingly. This is
+ * usually done once at application startup.
+ *
  * @param <T> The type of object that this {@link TableSchema} maps to.
  */
 @SdkPublicApi
@@ -101,6 +104,10 @@ private ImmutableTableSchema(StaticImmutableTableSchema<T, ?> wrappedTableSchema
     /**
      * Scans an immutable class and builds an {@link ImmutableTableSchema} from it that can be used with the
      * {@link DynamoDbEnhancedClient}.
+     *
+     * Creating an {@link ImmutableTableSchema} is a moderately expensive operation, and should be performed sparingly. This is
+     * usually done once at application startup.
+     *
      * @param immutableClass The annotated immutable class to build the table schema from.
      * @param <T> The immutable class type.
      * @return An initialized {@link ImmutableTableSchema}