From f4bd83f86ee1d5f50da274fec551da98f5fac49a Mon Sep 17 00:00:00 2001
From: "Brian S. O'Neill" <bronee@gmail.com>
Date: Fri, 27 Sep 2024 12:03:49 -0700
Subject: [PATCH] Add a leader state and failover operation.

---
 .../java/org/cojen/tupl/jmx/DatabaseMBean.java   |  4 ++++
 .../java/org/cojen/tupl/jmx/Registration.java    | 16 ++++++++++++++++
 2 files changed, 20 insertions(+)

diff --git a/src/main/java/org/cojen/tupl/jmx/DatabaseMBean.java b/src/main/java/org/cojen/tupl/jmx/DatabaseMBean.java
index 435811265..260787d45 100644
--- a/src/main/java/org/cojen/tupl/jmx/DatabaseMBean.java
+++ b/src/main/java/org/cojen/tupl/jmx/DatabaseMBean.java
@@ -43,6 +43,8 @@ public interface DatabaseMBean {
 
     long getReplicationBacklog();
 
+    boolean isLeader();
+
     void flush();
 
     void sync();
@@ -52,4 +54,6 @@ public interface DatabaseMBean {
     void compactFile(double target);
 
     void verify();
+
+    boolean failover();
 }
diff --git a/src/main/java/org/cojen/tupl/jmx/Registration.java b/src/main/java/org/cojen/tupl/jmx/Registration.java
index b0d7cfa72..5a14780d4 100644
--- a/src/main/java/org/cojen/tupl/jmx/Registration.java
+++ b/src/main/java/org/cojen/tupl/jmx/Registration.java
@@ -291,6 +291,12 @@ public long getReplicationBacklog() {
             return stats == null ? 0 : stats.replicationBacklog;
         }
 
+        @Override
+        public boolean isLeader() {
+            Database db = db();
+            return db == null ? false : db.isLeader();
+        }
+
         @Override
         public void flush() {
             asyncOp(db -> {
@@ -377,6 +383,16 @@ public boolean indexNodeFailed(long id, int level, String message) {
             }
         }
 
+        @Override
+        public boolean failover() {
+            try {
+                Database db = db();
+                return db == null ? false : db.failover();
+            } catch (IOException e) {
+                return false;
+            }
+        }
+
         private DatabaseStats stats() {
             synchronized (this) {
                 DatabaseStats stats = mStats;