1 files changed, 43 insertions, 0 deletions
diff --git a/filedistribution/src/main/java/com/yahoo/vespa/filedistribution/FileDistributionConnectionPool.java b/filedistribution/src/main/java/com/yahoo/vespa/filedistribution/FileDistributionConnectionPool.java
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+++ b/filedistribution/src/main/java/com/yahoo/vespa/filedistribution/FileDistributionConnectionPool.java
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+// Copyright Yahoo. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.filedistribution;
+
+import com.yahoo.config.subscription.ConfigSourceSet;
+import com.yahoo.jrt.Supervisor;
+import com.yahoo.vespa.config.Connection;
+import com.yahoo.vespa.config.JRTConnection;
+import com.yahoo.vespa.config.JRTConnectionPool;
+
+import java.util.List;
+
+
+/**
+ * A pool of JRT connections to a set of file distribution source (one or more config servers).
+ * Used by file distribution clients, where the source that can serve a file reference might be
+ * different for each file reference (unlike config requests, where all requests should be served by the same source).
+ * A new connection is chosen randomly when calling {#link {@link #switchConnection(Connection failingConnection)}}.
+ * Unlike JRTConnectionPool there is no state that holds the 'current' connection, a new connection is picked
+ * randomly if {@link #getCurrent()} is called.
+ *
+ * @author hmusum
+ */
+public class FileDistributionConnectionPool extends JRTConnectionPool {
+
+    public FileDistributionConnectionPool(ConfigSourceSet sourceSet, Supervisor supervisor) {
+        super(sourceSet, supervisor);
+    }
+
+    @Override
+    public synchronized JRTConnection getCurrent() {
+        return pickNewConnectionRandomly(getSources());
+    }
+
+    @Override
+    public synchronized JRTConnection switchConnection(Connection failingConnection) {
+        if (getSources().size() <= 1) return getCurrent();
+
+        List<JRTConnection> sourceCandidates = getSources();
+        sourceCandidates.remove(failingConnection);
+        return pickNewConnectionRandomly(sourceCandidates);
+    }
+
+}