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diff --git a/container-search/src/main/java/com/yahoo/search/cluster/BaseNodeMonitor.java b/container-search/src/main/java/com/yahoo/search/cluster/BaseNodeMonitor.java
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+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.search.cluster;
+
+import java.util.logging.Logger;
+
+import com.yahoo.search.result.ErrorMessage;
+
+
+/**
+ * A node monitor is responsible for maintaining the state of a monitored node.
+ * It has the following properties:
+ * <ul>
+ * <li>A node is taken out of operation if it fails</li>
+ * <li>A node is put back in operation when it responds correctly again
+ *     <i>responseAfterFailLimit</i> times <b>unless</b>
+ *     it has failed <i>failQuarantineLimit</i>. In the latter case it won't
+ *     be put into operation again before that time period has expired</li>
+ * </ul>
+ *
+ * @author bratseth
+ */
+public abstract class BaseNodeMonitor<T> {
+
+    protected static Logger log=Logger.getLogger(BaseNodeMonitor.class.getName());
+
+    /** The object representing the monitored node */
+    protected T node;
+
+    protected boolean isWorking=true;
+
+    /** Whether this node is quarantined for unstability */
+    protected boolean isQuarantined=false;
+
+    /** The last time this node failed, in ms */
+    protected long failedAt=0;
+
+    /** The last time this node responded (failed or succeeded), in ms */
+    protected long respondedAt=0;
+
+    /** The last time this node responded successfully */
+    protected long succeededAt=0;
+
+    /** The configuration of this monitor */
+    protected MonitorConfiguration configuration;
+
+    /** Is the node we monitor part of an internal Vespa cluster or not */
+    private boolean internal=false;
+
+    public BaseNodeMonitor(boolean internal) {
+        this.internal=internal;
+    }
+
+    public T getNode() { return node; }
+
+    /**
+     * Returns whether this node is currently in a state suitable
+     * for receiving traffic. As far as we know, that is
+     */
+    public boolean isWorking() { return isWorking; }
+
+    public boolean isQuarantined() { return isQuarantined; }
+
+    /**
+     * Called when this node fails.
+     *
+     * @param error a description of the error
+     */
+    public abstract void failed(ErrorMessage error);
+
+    /**
+     * Called when a response is received from this node. If the node was
+     * quarantined and it has been in that state for more than QuarantineTime
+     * milliseconds, it is taken out of quarantine.
+     *
+     * if it is not in quarantine but is not working, it may be set to working
+     * if this method is called at least responseAfterFailLimit times
+     */
+    public abstract void responded();
+
+    public boolean isIdle() {
+        return (now()-respondedAt) >= configuration.getIdleLimit();
+    }
+
+    protected long now() {
+        return System.currentTimeMillis();
+    }
+
+    /** Thread-safely changes the state of this node if required */
+    protected abstract void setWorking(boolean working,String explanation);
+
+    /** Returns whether or not this is monitoring an internal node. Default is false. */
+    public boolean isInternal() { return internal; }
+}