1 files changed, 120 insertions, 0 deletions
diff --git a/statistics/src/main/java/com/yahoo/statistics/ValueGroup.java b/statistics/src/main/java/com/yahoo/statistics/ValueGroup.java
new file mode 100644
index 00000000000..e9886c7757c
--- /dev/null
+++ b/statistics/src/main/java/com/yahoo/statistics/ValueGroup.java
@@ -0,0 +1,120 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.statistics;
+
+
+import com.yahoo.log.event.Event;
+import com.yahoo.statistics.Value.Parameters;
+
+import java.util.Iterator;
+import java.util.Map;
+import java.util.HashMap;
+
+/**
+ * A set of related values which should be logged together.
+ *
+ * @author  <a href="mailto:steinar@yahoo-inc.com">Steinar Knutsen</a>
+ */
+public class ValueGroup extends Group {
+    // A map for names of subevents and Value instances
+    private Map<String, Value> subEvents = new HashMap<>();
+
+    /**
+     * Create a ValueGroup.
+     *
+     * @param name
+     *            The symbolic name of this group of values
+     * @param manager
+     *            the statistics manager acquired by injection
+     */
+    public ValueGroup(String name, Statistics manager) {
+        this(name, manager, null);
+    }
+
+    /**
+     * Create a ValueGroup.
+     *
+     * @param name
+     *            The symbolic name of this group of values
+     * @param manager
+     *            the statistics manager acquired by injection
+     * @param callback
+     *            will be invoked each time data is written to the log
+     */
+    public ValueGroup(String name, Statistics manager, Callback callback) {
+        super(name, manager, callback);
+        manager.register(this);
+    }
+
+    /**
+     * Put a value into the named value in the group.
+     */
+    public void put(String name, double x) {
+        Value v = getValue(name);
+        v.put(x);
+    }
+
+    /**
+     * Get a value with a given name, creates a new value if no
+     * value with the name given exists.
+     *
+     */
+    synchronized Value getValue(String name) {
+        Value v = subEvents.get(name);
+        if (v == null) {
+            v = getNewValue(name);
+        }
+        return v;
+    }
+
+    private Value getNewValue(String subName) {
+        Value v = Value.initializeUnregisteredValue(subName, new Parameters().setLogRaw(true));
+        subEvents.put(subName, v);
+        return v;
+    }
+
+    /**
+     * Dump state to log and reset.
+     */
+    @Override
+    public void runHandle() {
+        StringBuilder multi = new StringBuilder();
+        ValueProxy[] proxies;
+        int i = 0;
+
+        synchronized (this) {
+            proxies = new ValueProxy[subEvents.size()];
+            i = 0;
+            for (Iterator<Value> j = subEvents.values().iterator(); j.hasNext();) {
+                Value v = j.next();
+                proxies[i] = v.getProxyAndReset();
+                i++;
+            }
+        }
+
+        while (i > 0) {
+            i--;
+            if (multi.length() > 0) {
+                multi.append(", ");
+            }
+            multi.append(proxies[i].getName());
+            multi.append("=");
+            multi.append(proxies[i].getRaw());
+        }
+
+        Event.valueGroup(getName(), multi.toString());
+    }
+
+    @Override
+    public boolean equals(Object o) {
+        if (o.getClass() != this.getClass()) {
+            return false;
+        }
+        ValueGroup other = (ValueGroup) o;
+        return getName().equals(other.getName());
+    }
+
+    @Override
+    public int hashCode() {
+        return getName().hashCode() + 31 * "ValueGroup".hashCode();
+    }
+}