KOP-2139 javadoc: Add documentation XtaClient

src/main/java/de/ozgcloud/xta/client/XtaClient.java

@@ -24,6 +24,16 @@ public class XtaClient {
 	private final WrappedXtaService service;
 	private final XtaClientConfig config;
 
+	/**
+	 * Fetch metadata of pending messages sent to the {@code xtaIdentifier}.
+	 * The returned listing contains at most {@link de.ozgcloud.xta.client.config.XtaClientConfig#getMaxListItems() maxListItems} messages.
+	 * Use the {@code requestId} to {@link #close(String) close} pending messages.
+	 * To fetch the next messages, use {@link #getNextMessagesMetadata(String)}.
+	 * Note that {@code xtaIdentifier} has to be configured as a {@link de.ozgcloud.xta.client.config.XtaClientConfig#getClientIdentifiers() clientIdentifiers}.
+	 *
+	 * @param xtaIdentifier the client identifier value to fetch messages for
+	 * @return the listing result with metadata of messages
+	 */
 	public XtaMessageMetaDataListing getMessagesMetadata(@NotBlank String xtaIdentifier)
 			throws XTAWSTechnicalProblemException, PermissionDeniedException {
 		var clientIdentifier = deriveIdentifier(xtaIdentifier);
@@ -31,6 +41,10 @@ public class XtaClient {
 		return getStatusList(clientIdentifier);
 	}
 
+	/**
+	 * Fetch metadata of pending messages sent to the {@code xtaIdentifier}.
+	 * This method skips checks but otherwise behaves exactly as {@link #getMessagesMetadata(String)}.
+	 */
 	public XtaMessageMetaDataListing getNextMessagesMetadata(@NotBlank String xtaIdentifier)
 			throws XTAWSTechnicalProblemException, PermissionDeniedException {
 		return getStatusList(deriveIdentifier(xtaIdentifier));