From c2aa9706ed3b45fa0f63f52eb22d9019881be95a Mon Sep 17 00:00:00 2001
From: Jean-Yves TINEVEZ <tinevez@pasteur.fr>
Date: Mon, 22 Jun 2026 16:48:46 +0200
Subject: [PATCH] Utility interface for classes that provide listeners to
 Appose events.

This is expected to be useful for 3rd party developers that implement
general Python tools via Appose. Appose env builder and python task
execution generate events that are communicated via:
- for env installation and downloading: a progress listener, an output
listener and an error listener.
- for task execution: a task listener.

Users can specify their own implementation, but this would require
writing methods with a signature with 4 added parameters. To
simplify this, the interface proposed here groups them in one,
with an added close() method to hide any log widget that could have
popped up.
---
 .../apposed/appose/util/ApposeListener.java   | 59 +++++++++++++++++++
 1 file changed, 59 insertions(+)
 create mode 100644 src/main/java/org/apposed/appose/util/ApposeListener.java

diff --git a/src/main/java/org/apposed/appose/util/ApposeListener.java b/src/main/java/org/apposed/appose/util/ApposeListener.java
new file mode 100644
index 0000000..22bb22a
--- /dev/null
+++ b/src/main/java/org/apposed/appose/util/ApposeListener.java
@@ -0,0 +1,59 @@
+package org.apposed.appose.util;
+
+import java.util.function.Consumer;
+
+import org.apposed.appose.Builder.ProgressConsumer;
+import org.apposed.appose.TaskEvent;
+
+/**
+ * Utility interface for classes that provide listeners to Appose events.
+ */
+public interface ApposeListener
+{
+
+
+	/**
+	 * Returns a consumer that will be called with task events related to the
+	 * execution of an Appose task, and that writes messages in the outputs
+	 * defined in this class.
+	 * 
+	 * @return a new task event consumer.
+	 */
+	Consumer< TaskEvent > taskListener();
+
+	/**
+	 * Returns a consumer that will be called with output messages related to
+	 * the downloading, installation and deployment of an Appose environment,
+	 * and that writes messages in the outputs defined in this class.
+	 * 
+	 * @return a new output message consumer.
+	 */
+	Consumer< String > outputListener();
+
+	/**
+	 * Returns a consumer that will be called with error messages related to the
+	 * the downloading, installation and deployment of an Appose environment,
+	 * and that writes messages in the outputs defined in this class.
+	 * 
+	 * @return a new error message consumer.
+	 */
+	Consumer< String > errorListener();
+
+	/**
+	 * Returns a consumer that will be called with progress updates related to
+	 * the downloading, installation and deployment of an Appose environment,
+	 * and that writes messages in the outputs defined in this class.
+	 * 
+	 * @return a new progress update consumer.
+	 */
+	ProgressConsumer progressListener();
+
+	/**
+	 * Closes the listener and releases any resources it may be holding. This
+	 * method should be called 1/ after the the downloading, installation and
+	 * deployment phase and 2/ after the execution of an Appose task is
+	 * completed.
+	 */
+	void close();
+
+}