NIFI-15574 Added the Javadoc snippet tag for the code examples in the Nifi API Javadocs.

src/main/java/org/apache/nifi/components/ConfigurableComponent.java

@@ -63,7 +63,7 @@ public interface ConfigurableComponent {
      * onPropertyModified method. This can be done as follows:
      * </p>
      *
-     * <pre>{@code
+     * {@snippet :
      *    private volatile boolean configurationRestored = false;
      *
      *    @OnConfigurationRestored
@@ -76,7 +76,7 @@ public interface ConfigurableComponent {
      *            return;
      *        }
      *    }
-     * }</pre>
+     * }
      *
      * @param descriptor the descriptor for the property being modified
      * @param oldValue the value that was previously set. Will be <code>null</code> if no value

src/main/java/org/apache/nifi/components/PropertyDescriptor.java

@@ -561,9 +561,15 @@ private boolean isValueAllowed(final String value) {
          * Any property descriptor that identifies an external resource will be automatically validated against the following rules:
          * <ul>
          *     <li>If the ResourceCardinality is SINGLE, the given property value must be a file, a directory, or a URL that uses a protocol of http/https/file.</li>
-         *     <li>The given resourceTypes dictate which types of input are allowed. For example, if <code>identifiesExternalResource(ResourceCardinality.SINGLE, ResourceType.FILE)</code>
-         *     is used, the input must be a regular file. If <code>identifiesExternalResource(ResourceCardinality.SINGLE, ResourceType.FILE, ResourceType.DIRECTORY)</code> is used, then the input
-         *     must be exactly one file OR directory.
+         *     <li>The given resourceTypes dictate which types of input are allowed. For example, if
+         *     {@snippet :
+         *        identifiesExternalResource(ResourceCardinality.SINGLE, ResourceType.FILE)
+         *     }
+         *     is used, the input must be a regular file. If
+         *     {@snippet :
+         *        identifiesExternalResource(ResourceCardinality.SINGLE, ResourceType.FILE, ResourceType.DIRECTORY)
+         *     }
+         *     is used, then the input must be exactly one file OR directory.
          *     </li>
          *     <li>If the ResourceCardinality is MULTIPLE, the given property value may consist of one or more resources, each separated by a comma and optional white space.</li>
          * </ul>

src/main/java/org/apache/nifi/controller/ControllerService.java

@@ -70,21 +70,22 @@
  * <p>
  * For example:
  * </p>
- * <pre><code>
+ * {@snippet :
  *    public static final PropertyDescriptor MY_PROPERTY = new PropertyDescriptor.Builder()
  *     .name("My Property")
  *     .description("Example Property")
  *     .identifiesControllerService( MyControllerServiceInterface.class )
  *     .build();
  *
- *    ...
+ *    // Other code
+ *
  *    public void onTrigger(ProcessContext context, ProcessSessionFactory sessionFactory) throws ProcessException {
  *     // Obtain the user-selected controller service
  *     final MyControllerServiceInterface service = context.getProperty(MY_PROPERTY).asControllerService( MyControllerServiceInterface.class );
- *     ...
- *    }
  *
- * </code></pre>
+ *      // Other code
+ *    }
+ * }
  * <li>A Controller Service can be obtained via a
  * {@link ControllerServiceLookup}. This lookup may be obtained, for example,
  * from the {@link ProcessContext} that is provided to a {@link Processor}'s
@@ -94,11 +95,11 @@
  * For example:
  * </p>
  *
- * <pre><code>
+ * {@snippet :
  *    public void onTrigger(ProcessContext context, ProcessSessionFactory sessionFactory) throws ProcessException {
  *      final MyControllerServiceInterface service = (MyControllerServiceInterface) context.getControllerServiceLookup().getControllerService("service_identifier");
  *    }
- * </code></pre>
+ * }
  * </li>
  * </ul>
  *
@@ -139,14 +140,14 @@
  *
  * <p>
  * Typically, this is done by creating a NAR structure as follows:
- * <pre>
+ * {@snippet lang="text" :
  *   + my-services-api-nar
  *   +--- service-X-implementation-nar
  *   +--- service-Y-implementation-nar
  *   +--- service-Z-implementation-nar
  *   +--- processor-A-nar
  *   +--- processor-B-nar
- * </pre>
+ * }
  *
  * <p>
  * In this case, the {@code MyControllerServiceInterface} interface, and any

src/main/java/org/apache/nifi/migration/PropertyConfiguration.java

@@ -50,9 +50,9 @@ public interface PropertyConfiguration {
      * <p>
      *     An idiom to determine if the property was explicitly set to <code>null</code> is as follows:
      * </p>
-     * <pre><code>
-     *     final boolean setToNull = configuration.hasProperty("MyProperty") &amp;&amp; !configuration.isPropertySet("MyProperty");
-     * </code></pre>
+     * {@snippet :
+     *  final boolean setToNull = configuration.hasProperty("MyProperty") && !configuration.isPropertySet("MyProperty");
+     * }
      *
      * @param propertyName the name of the property
      * @return <code>true</code> if the property name is known to this configuration, <code>false</code> otherwise.
@@ -69,9 +69,9 @@ public interface PropertyConfiguration {
      * <p>
      *     An idiom to determine if the property was explicitly set to <code>null</code> is as follows:
      * </p>
-     * <pre><code>
-     *     final boolean setToNull = configuration.hasProperty(MY_PROPERTY) &amp;&amp; !configuration.isSet(MY_PROPERTY);
-     * </code></pre>
+     * {@snippet :
+     *  final boolean setToNull = configuration.hasProperty(MY_PROPERTY) && !configuration.isSet(MY_PROPERTY);
+     * }
      *
      * @param descriptor the property descriptor that identifies the property
      * @return <code>true</code> if the property name is known to this configuration, <code>false</code> otherwise.
@@ -176,10 +176,10 @@ default Optional<String> getRawPropertyValue(PropertyDescriptor descriptor) {
      * use this method as such:
      * </p>
      *
-     * <pre><code>
+     * {@snippet :
      *     // Create a new Controller Service of type org.apache.nifi.services.authentication.UsernamePassword whose Username and Password
      *     // properties match those currently configured for this Processor.
-     *     final Map&lt;String, String&gt; serviceProperties = Map.of("Username", propertyConfiguration.getRawPropertyValue("Username"),
+     *     final Map<String, String> serviceProperties = Map.of("Username", propertyConfiguration.getRawPropertyValue("Username"),
      *          "Password", propertyConfiguration.getRawPropertyValue("Password"));
      *     final String serviceId = propertyConfiguration.createControllerService("org.apache.nifi.services.authentication.UsernamePassword", serviceProperties);
      *
@@ -189,7 +189,7 @@ default Optional<String> getRawPropertyValue(PropertyDescriptor descriptor) {
      *     // Remove the Username and Password properties from this Processor, since we are now going to use then Authentication Service.
      *     propertyConfiguration.removeProperty("Username");
      *     propertyConfiguration.removeProperty("Password");
-     * </code></pre>
+     * }
      *
      * <p>
      * Note the use of {@link #getRawPropertyValue(String)} here instead of {@link #getPropertyValue(String)}. Because we want to set

src/main/java/org/apache/nifi/migration/RelationshipConfiguration.java

@@ -58,9 +58,9 @@ public interface RelationshipConfiguration {
      * It is possible to split an existing relationship into the same relationship and additional relationships. For example, it is
      * valid to call this method as:
      * </p>
-     * <pre><code>
-     * relationshipConfiguration.splitRelationship("A", "A", "B", "C");
-     * </code></pre>
+     * {@snippet :
+     *      relationshipConfiguration.splitRelationship("A", "A", "B", "C");
+     * }
      *
      * <p>
      * In order to split the "A" relationship into three relationships: "A", "B", and "C". However, upon restart, NiFi will have already split the "A"
@@ -69,11 +69,11 @@ public interface RelationshipConfiguration {
      * exist first:
      * </p>
      *
-     * <pre><code>
-     * if (!relationshipConfiguration.hasRelationship("B")) {
-     *     relationshipConfiguration.splitRelationship("A", "A", "B", "C");
+     * {@snippet :
+     *     if (!relationshipConfiguration.hasRelationship("B")) {
+     *         relationshipConfiguration.splitRelationship("A", "A", "B", "C");
+     *     }
      * }
-     * </code></pre>
      *
      * <p>
      * This ensures that we do not attempt to split relationship "A" if it has already been done.

src/main/java/org/apache/nifi/processor/ProcessSession.java

@@ -105,24 +105,24 @@ public interface ProcessSession {
      * and implementing that action in the provided callback.
      * <p>
      * As a result, the following very common idiom:
-     * <pre><code>
-     * getDataFromSource();
-     * session.commit();
-     * acknowledgeReceiptOfData();
-     * </code></pre>
+     * {@snippet :
+     *     getDataFromSource();
+     *     session.commit();
+     *     acknowledgeReceiptOfData();
+     * }
      * Cannot be simply changed to:
-     * <pre><code>
-     * getDataFromSource();
-     * session.commitAsync();
-     * acknowledgeReceiptOfData();
-     * </code></pre>
+     * {@snippet :
+     *     getDataFromSource();
+     *     session.commitAsync();
+     *     acknowledgeReceiptOfData();
+     * }
      * Doing so could result in acknowledging receipt of data from the source system before data has been committed to the repositories.
      * If NiFi were to then be restarted, there is potential for data loss.
      * Rather, the following idiom should take its place to ensure that there is no data loss:
-     * <pre><code>
-     * getDataFromSource();
-     * session.commitAsync( () -> acknowledgeReceiptOfData() );
-     * </code></pre>
+     * {@snippet :
+     *     getDataFromSource();
+     *     session.commitAsync( () -> acknowledgeReceiptOfData() );
+     * }
      * <p>
      * If the session cannot be committed, an error will be logged and the session will be rolled back instead.
      *

src/main/java/org/apache/nifi/time/DurationFormat.java

@@ -72,13 +72,13 @@ public static long getTimeDuration(final String value, final TimeUnit desiredUni
      * This method handles decimal values over {@code 1 ns}, but {@code < 1 ns} will return {@code 0} in any other unit.
      * <p>
      * Examples:
-     * <p>
-     * "10 seconds", {@code TimeUnit.MILLISECONDS} -> 10_000.0
-     * "0.010 s", {@code TimeUnit.MILLISECONDS} -> 10.0
-     * "0.010 s", {@code TimeUnit.SECONDS} -> 0.010
-     * "0.010 ns", {@code TimeUnit.NANOSECONDS} -> 1
-     * "0.010 ns", {@code TimeUnit.MICROSECONDS} -> 0
-     *
+     * {@snippet lang="text" :
+     *    "10 seconds", {@code TimeUnit.MILLISECONDS} -> 10_000.0
+     *    "0.010 s", {@code TimeUnit.MILLISECONDS} -> 10.0
+     *    "0.010 s", {@code TimeUnit.SECONDS} -> 0.010
+     *    "0.010 ns", {@code TimeUnit.NANOSECONDS} -> 1
+     *    "0.010 ns", {@code TimeUnit.MICROSECONDS} -> 0
+     * }
      * @param value       the {@code String} input
      * @param desiredUnit the desired output {@link TimeUnit}
      * @return the parsed and converted amount (without a unit)