- Added Metrics to extract metrics for micrometer (https://issues.red…

…hat.com/browse/JGRP-2796)

- ResourceDMBean now accepts filters (JGRP-2796)
- Added AttributeType.SCALAR to selected attributes
- JChannelProbeHandler now supports "metrics" key to dump metrics

src/org/jgroups/JChannelProbeHandler.java

@@ -5,6 +5,7 @@
 import org.jgroups.logging.LogFactory;
 import org.jgroups.stack.DiagnosticsHandler;
 import org.jgroups.stack.Protocol;
+import org.jgroups.util.Metrics;
 import org.jgroups.util.Util;
 
 import java.lang.management.ManagementFactory;
@@ -55,6 +56,20 @@ public Map<String, String> handleProbe(String... keys) {
                 }
                 continue;
             }
+            if(key.startsWith("metrics")) {
+                Map<String,Map<String,Metrics.Entry<Object>>> m=Metrics.extract(ch, Metrics.IS_NUMBER);
+                Map<String,Map<String,Metrics.Entry<Number>>> metrics=Metrics.convert(m);
+                StringBuilder sb=new StringBuilder();
+                for(Map.Entry<String,Map<String,Metrics.Entry<Number>>> e: metrics.entrySet()) {
+                    sb.append(String.format("%s:\n", e.getKey()));
+                    for(Map.Entry<String,Metrics.Entry<Number>> e2: e.getValue().entrySet()) {
+                        Metrics.Entry<Number> val=e2.getValue();
+                        sb.append(String.format("   %s: %s\n", e2.getKey(), e2.getValue().supplier().get()));
+                    }
+                }
+                map.put(key, sb.toString());
+                continue;
+            }
             if(key.startsWith("threads")) {
                 ThreadMXBean bean=ManagementFactory.getThreadMXBean();
                 boolean cpu_supported=bean.isThreadCpuTimeSupported();
@@ -178,7 +193,7 @@ else if(val.startsWith("wtime"))
     }
 
     public String[] supportedKeys() {
-        return new String[]{"reset-stats", "jmx", "op=<operation>[<args>]", "ops",
+        return new String[]{"reset-stats", "jmx", "op=<operation>[<args>]", "ops", "metrics",
           "threads[=<filter>[=<limit>]]", "enable-cpu", "enable-contention", "disable-cpu", "disable-contention"};
     }
 

src/org/jgroups/jmx/ResourceDMBean.java

@@ -7,6 +7,7 @@
 import org.jgroups.conf.AttributeType;
 import org.jgroups.logging.Log;
 import org.jgroups.logging.LogFactory;
+import org.jgroups.util.Average;
 import org.jgroups.util.Util;
 
 import javax.management.*;
@@ -43,7 +44,7 @@ public class ResourceDMBean implements DynamicMBean {
     protected final boolean                        expose_all;
     protected final Log                            log=LogFactory.getLog(ResourceDMBean.class);
     protected final Object                         obj;
-    protected List<Object>                         objs;
+    protected List<Object>                         components;
     protected final MBeanAttributeInfo[]           attrInfo;
     protected final MBeanOperationInfo[]           opInfo;
     protected final HashMap<String,AttributeEntry> atts=new HashMap<>();
@@ -54,27 +55,31 @@ public class ResourceDMBean implements DynamicMBean {
     protected static final Predicate<AccessibleObject> FILTER=obj -> obj.isAnnotationPresent(ManagedAttribute.class) ||
       (obj.isAnnotationPresent(Property.class) && obj.getAnnotation(Property.class).exposeAsManagedAttribute());
 
-
     public ResourceDMBean(Object instance) {
+        this(instance, null);
+    }
+
+    public ResourceDMBean(Object instance, Predicate<AccessibleObject> filter) {
         if(instance == null)
             throw new NullPointerException("Cannot make an MBean wrapper for null instance");
         this.obj=instance;
         Class<? extends Object> c=obj.getClass();
         expose_all=c.isAnnotationPresent(MBean.class) && c.getAnnotation(MBean.class).exposeAll();
 
-        findFields(instance);
-        findMethods(instance);
+        findFields(instance, filter, null);
+        findMethods(instance, filter, null);
         fixFields(instance);
 
         List<Object> objects=Util.getComponents(instance);
         if(objects != null) {
             for(Object inst: objects) {
                 if(inst != null) {
-                    if(objs == null)
-                        objs=new ArrayList<>();
-                    objs.add(inst);
-                    findFields(inst);
-                    findMethods(inst);
+                    if(components == null)
+                        components=new ArrayList<>();
+                    String prefix=Util.methodNameToAttributeName(inst.getClass().getSimpleName());
+                    components.add(inst);
+                    findFields(inst, filter, prefix);
+                    findMethods(inst, filter, prefix);
                     fixFields(inst);
                 }
             }
@@ -150,8 +155,8 @@ public Object invoke(String name, Object[] args, String[] sig) throws MBeanExcep
             for(int i=0;i < classes.length;i++)
                 classes[i]=getClassForName(sig[i]);
             Method method=null;
-            if(objs != null) {
-                for(Object o: objs) {
+            if(components != null) {
+                for(Object o: components) {
                     try {
                         method=o.getClass().getMethod(name, classes);
                     }
@@ -273,6 +278,10 @@ public static boolean isFractional(Class<?> cl) {
         return cl.equals(float.class) || cl.equals(Float.class) || cl.equals(double.class) || cl.equals(Double.class);
     }
 
+    public static boolean isNumber(Class<?> cl) {
+        return isNumeric(cl) || isFractional(cl) || Number.class.isAssignableFrom(cl) || Average.class.isAssignableFrom(cl);
+    }
+
 
     protected static AttributeType getType(AccessibleObject ao) {
         Property prop=ao.getAnnotation(Property.class);
@@ -306,15 +315,18 @@ protected static Class<?> getClassForName(String name) throws ClassNotFoundExcep
         throw new ClassNotFoundException("Class " + name + " cannot be found");
     }
 
-    protected void findMethods(Object instance) {
+    protected void findMethods(Object instance, Predicate<AccessibleObject> filter, String prefix) {
         // find all methods but don't include methods from Object class
         List<Method> methods = new ArrayList<>(Arrays.asList(instance.getClass().getMethods()));
         methods.removeAll(OBJECT_METHODS);
 
         for(Method method: methods) {
+
             // does method have @ManagedAttribute annotation?
             if(method.isAnnotationPresent(ManagedAttribute.class) || method.isAnnotationPresent(Property.class)) {
-                exposeManagedAttribute(method, instance);
+                if(filter != null && !filter.test(method))
+                    continue;
+                exposeManagedAttribute(method, instance, prefix);
             }
             //or @ManagedOperation
             else if (method.isAnnotationPresent(ManagedOperation.class) || expose_all){
@@ -338,7 +350,7 @@ protected void fixFields(Object instance) {
 
 
 
-    protected void exposeManagedAttribute(Method method, Object instance) {
+    protected void exposeManagedAttribute(Method method, Object instance, String prefix) {
         String           methodName=method.getName();
         ManagedAttribute attr_annotation=method.getAnnotation(ManagedAttribute.class);
         Property         prop=method.getAnnotation(Property.class);
@@ -367,7 +379,7 @@ protected void exposeManagedAttribute(Method method, Object instance) {
         }
 
         String descr=attr_annotation != null ? attr_annotation.description() : prop != null? prop.description() : null;
-        AttributeEntry attr=atts.get(attr_name);
+        AttributeEntry attr=atts.get(prefix(prefix,attr_name));
         if(attr != null) {
             if(isSetMethod(method)) {
                 if(attr.setter != null) {
@@ -389,17 +401,19 @@ protected void exposeManagedAttribute(Method method, Object instance) {
         else { // create a new entry in atts
             boolean is_setter=isSetMethod(method);
             String type=is_setter? method.getParameterTypes()[0].getCanonicalName() : method.getReturnType().getCanonicalName();
-            MBeanAttributeInfo info=new MBeanAttributeInfo(attr_name, type, descr, true, writable, methodName.startsWith("is"));
-            AttributeEntry entry=new AttributeEntry(Util.methodNameToAttributeName(methodName), info);
+            MBeanAttributeInfo info=new MBeanAttributeInfo(prefix(attr_name, prefix), type, descr, true, writable, methodName.startsWith("is"));
+            AttributeEntry entry=new AttributeEntry(method, Util.methodNameToAttributeName(methodName), info);
             if(is_setter)
                 entry.setter(new MethodAccessor(method, instance));
             else
                 entry.getter(new MethodAccessor(method, instance));
-            atts.put(attr_name, entry);
+            atts.put(prefix(attr_name, prefix), entry);
         }
     }
 
-
+    protected static String prefix(String s, String prefix) {
+        return prefix == null? s : prefix + "." + s;
+    }
 
     /** Finds an accessor for an attribute. Tries to find getAttrName(), isAttrName(), attrName() methods. If not
      * found, tries to use reflection to get the value of attr_name. If still not found, creates a NullAccessor. */
@@ -416,7 +430,6 @@ protected static Accessor findGetter(Object target, String attr_name) {
         Field field=Util.getField(clazz, attr_name);
         if(field != null)
             return new FieldAccessor(field, target);
-
         return new NoopAccessor();
     }
 
@@ -461,24 +474,28 @@ protected static String toLowerCase(String input) {
     }
 
 
-    protected void findFields(Object instance) {
+    protected void findFields(Object instance, Predicate<AccessibleObject> filter, String prefix) {
         // traverse class hierarchy and find all annotated fields
         for(Class<?> clazz=instance.getClass(); clazz != null && clazz != Object.class; clazz=clazz.getSuperclass()) {
-
             Field[] fields=clazz.getDeclaredFields();
             for(Field field: fields) {
-                ManagedAttribute attr=field.getAnnotation(ManagedAttribute.class);
+                ManagedAttribute annotation=field.getAnnotation(ManagedAttribute.class);
                 Property prop=field.getAnnotation(Property.class);
                 boolean expose_prop=prop != null && prop.exposeAsManagedAttribute();
-                boolean expose=attr != null || expose_prop;
+                boolean expose=annotation != null || expose_prop;
 
                 if(expose) {
-                    String fieldName=attr != null? attr.name() : (prop != null? prop.name() : null);
+                    if(filter != null && !filter.test(field))
+                        continue;
+
+                    String fieldName=annotation != null? annotation.name() : (prop != null? prop.name() : null);
                     if(fieldName != null && fieldName.trim().isEmpty())
                         fieldName=field.getName();
+                    if(prefix != null)
+                        fieldName=prefix + "." + fieldName;
 
-                    String descr=attr != null? attr.description() : prop.description();
-                    boolean writable=attr != null? attr.writable() : prop.writable();
+                    String descr=annotation != null? annotation.description() : prop.description();
+                    boolean writable=annotation != null? annotation.writable() : prop.writable();
 
                     MBeanAttributeInfo info=new MBeanAttributeInfo(fieldName,
                                                                    field.getType().getCanonicalName(),
@@ -487,7 +504,7 @@ protected void findFields(Object instance) {
                                                                    !Modifier.isFinal(field.getModifiers()) && writable,
                                                                    false);
 
-                    atts.put(fieldName, new AttributeEntry(field.getName(), info));
+                    atts.put(fieldName, new AttributeEntry(field, field.getName(), info));
                 }
             }
         }
@@ -531,25 +548,27 @@ protected boolean setNamedAttribute(Attribute attribute) {
 
 
     public static class AttributeEntry {
-
+        protected final AccessibleObject   type; // method of field
         /** The name of the field or method. Can be different from the key in atts when name in @Property or
          * @ManagedAttribute  was used */
         protected final String             name;
         protected final MBeanAttributeInfo info;
         protected Accessor                 getter;
         protected Accessor                 setter;
 
-        public AttributeEntry(String name, MBeanAttributeInfo info) {
-            this(name, info, null, null);
+        public AttributeEntry(AccessibleObject type, String name, MBeanAttributeInfo info) {
+            this(type, name, info, null, null);
         }
 
-        public AttributeEntry(String name, MBeanAttributeInfo info, Accessor getter, Accessor setter) {
+        public AttributeEntry(AccessibleObject type, String name, MBeanAttributeInfo info, Accessor getter, Accessor setter) {
+            this.type=type;
             this.name=name;
             this.info=info;
             this.getter=getter;
             this.setter=setter;
         }
 
+        public AccessibleObject   type()                      {return type;}
         public String             name()                      {return name;}
         public MBeanAttributeInfo info()                      {return info;}
         public Accessor           getter()                    {return getter;}

src/org/jgroups/protocols/BARRIER.java

@@ -86,7 +86,7 @@ public int getNumberOfInFlightThreads() {
         return in_flight_threads.size();
     }
 
-    @ManagedAttribute
+    @ManagedAttribute(description="Number of threads in flight",type=AttributeType.SCALAR)
     public int getInFlightThreadsCount() {
         return getNumberOfInFlightThreads();
     }

src/org/jgroups/protocols/Discovery.java

@@ -87,7 +87,7 @@ public abstract class Discovery extends Protocol {
 
     /* ---------------------------------------------   JMX      ------------------------------------------------------ */
 
-    @ManagedAttribute(description="Total number of discovery requests sent ")
+    @ManagedAttribute(description="Total number of discovery requests sent",type=AttributeType.SCALAR)
     protected int                        num_discovery_requests;
 
     /* --------------------------------------------- Fields ------------------------------------------------------ */

src/org/jgroups/protocols/FD_SOCK2.java

@@ -75,7 +75,7 @@ public class FD_SOCK2 extends Protocol implements Receiver, ConnectionListener,
     @Property(description="SO_LINGER in seconds. Default of -1 disables it")
     protected int                            linger=-1; // SO_LINGER (number of seconds, -1 disables it)
 
-    @ManagedAttribute(description="Number of suspect events emitted")
+    @ManagedAttribute(description="Number of suspect events emitted",type=AttributeType.SCALAR)
     protected int                            num_suspect_events;
 
     @ManagedAttribute(description="True when this member is leaving the cluster, set to false when joining")

src/org/jgroups/protocols/MERGE3.java

@@ -89,7 +89,7 @@ public class MERGE3 extends Protocol {
     @ManagedAttribute(description="Whether or not the current member is the coordinator")
     protected volatile boolean              is_coord;
 
-    @ManagedAttribute(description="Number of times a MERGE event was sent up the stack")
+    @ManagedAttribute(description="Number of times a MERGE event was sent up the stack",type=AttributeType.SCALAR)
     protected int                           num_merge_events;
 
 

src/org/jgroups/protocols/MsgStats.java

@@ -45,6 +45,7 @@ public class MsgStats {
     protected final LongAdder     num_batches_received=new LongAdder();
 
     /** The average number of messages in a received {@link MessageBatch} */
+    @ManagedAttribute(description="Returns the average batch size of received batches")
     protected final AverageMinMax avg_batch_size=new AverageMinMax();
 
     @ManagedAttribute(description="Number of multicast bytes sent",type=BYTES)
@@ -66,10 +67,7 @@ public class MsgStats {
     @ManagedAttribute(description="Number of messages received (mcasts and ucasts received)",type=SCALAR)
     public long     getNumMsgsReceived()        {return num_mcasts_received.sum() + num_ucasts_received.sum();}
 
-    @ManagedAttribute(description="Returns the average batch size of received batches")
-    public String   getAvgBatchSize()           {return avg_batch_size.toString();}
-
-    public AverageMinMax avgBatchSize()         {return avg_batch_size;}
+    public AverageMinMax getAvgBatchSize()      {return avg_batch_size;}
 
     @ManagedAttribute(description="Total number of bytes sent (unicast + multicast bytes)",type=BYTES)
     public long     getNumBytesSent()           {return num_mcast_bytes_sent.sum() + num_ucast_bytes_sent.sum();}

src/org/jgroups/protocols/RED.java

@@ -48,7 +48,9 @@ public class RED extends Protocol {
       "longer to reflect the current queue size.")
     protected double          weight_factor=1;
 
+    @ManagedAttribute(description="The number of dropped messages",type=AttributeType.SCALAR)
     protected final LongAdder dropped_msgs=new LongAdder(); // dropped messages
+    @ManagedAttribute(description="Total number of messages processed",type=AttributeType.SCALAR)
     protected final LongAdder total_msgs=new LongAdder();   // total messages looked at
 
     protected Bundler         bundler;
@@ -60,17 +62,10 @@ public class RED extends Protocol {
     public boolean isEnabled()           {return enabled;}
     public RED     setEnabled(boolean e) {enabled=e; return this;}
     public double  getMinThreshold()     {return min_threshold;}
-
-
-
-    @ManagedAttribute(description="The number of dropped messages",type=AttributeType.SCALAR)
-    public long    getDroppedMessages() {return dropped_msgs.sum();}
-
-    @ManagedAttribute(description="Total number of messages processed",type=AttributeType.SCALAR)
-    public long    getTotalMessages()   {return total_msgs.sum();}
-
+    public long    getDroppedMessages()  {return dropped_msgs.sum();}
+    public long    getTotalMessages()    {return total_msgs.sum();}
     @ManagedAttribute(description="Percentage of all messages that were dropped")
-    public double  getDropRate()        {return dropped_msgs.sum() / (double)total_msgs.sum();}
+    public double  getDropRate()         {return dropped_msgs.sum() / (double)total_msgs.sum();}
 
 
     public void start() throws Exception {