File.deleteOnExit is not recursive. Replaced by DeleteFilesOnShutdown shutdown hook. Fixes #2971

arduino-core/src/cc/arduino/files/DeleteFilesOnShutdown.java

@@ -0,0 +1,42 @@
+package cc.arduino.files;
+
+import processing.app.helpers.FileUtils;
+
+import java.io.File;
+import java.util.Collections;
+import java.util.LinkedList;
+import java.util.List;
+
+public class DeleteFilesOnShutdown implements Runnable {
+
+  public static final DeleteFilesOnShutdown INSTANCE = new DeleteFilesOnShutdown();
+
+  public static void add(File file) {
+    INSTANCE.addFile(file);
+  }
+
+  private final List<File> files;
+
+  public DeleteFilesOnShutdown() {
+    this.files = new LinkedList<File>();
+  }
+
+  public synchronized void addFile(File file) {
+    this.files.add(file);
+  }
+
+  @Override
+  public void run() {
+    List<File> copyOfFiles;
+    synchronized (this) {
+      copyOfFiles = new LinkedList<File>(files);
+    }
+    Collections.reverse(copyOfFiles);
+    for (File file : copyOfFiles) {
+      if (file.exists() && file.canWrite()) {
+        FileUtils.recursiveDelete(file);
+      }
+    }
+  }
+
+}