add job service to be able to cancel plot requests

pdb-api/src/main/java/org/lucares/pdb/api/AbortException.java

@@ -0,0 +1,21 @@
+package org.lucares.pdb.api;
+
+public class AbortException extends RuntimeException {
+
+    private static final long serialVersionUID = 7614132985675048490L;
+
+    public AbortException() {
+        super();
+    }
+
+    public AbortException(final Throwable cause) {
+        super(cause);
+    }
+
+    public static void abortIfInterrupted() throws AbortException {
+        if (Thread.interrupted()) {
+            throw new AbortException();
+        }
+    }
+
+}