diff options
Diffstat (limited to 'src/share/classes/com/sun/jmx/namespace/NamespaceInterceptor.java')
| -rw-r--r-- | src/share/classes/com/sun/jmx/namespace/NamespaceInterceptor.java | 230 |
1 files changed, 3 insertions, 227 deletions
diff --git a/src/share/classes/com/sun/jmx/namespace/NamespaceInterceptor.java b/src/share/classes/com/sun/jmx/namespace/NamespaceInterceptor.java index da85fc6d4..6862066d2 100644 --- a/src/share/classes/com/sun/jmx/namespace/NamespaceInterceptor.java +++ b/src/share/classes/com/sun/jmx/namespace/NamespaceInterceptor.java @@ -25,22 +25,15 @@ package com.sun.jmx.namespace; import com.sun.jmx.defaults.JmxProperties; -import java.io.IOException; import java.util.ArrayList; -import java.util.Collections; import java.util.List; -import java.util.Set; -import java.util.UUID; import java.util.logging.Logger; import javax.management.Attribute; import javax.management.AttributeList; import javax.management.MBeanServer; -import javax.management.MBeanServerConnection; import javax.management.MalformedObjectNameException; import javax.management.ObjectName; -import javax.management.QueryExp; -import javax.management.namespace.JMXNamespaces; import javax.management.namespace.JMXNamespace; import javax.management.namespace.JMXNamespacePermission; @@ -54,12 +47,6 @@ import javax.management.namespace.JMXNamespacePermission; */ public class NamespaceInterceptor extends HandlerInterceptor<JMXNamespace> { - /** - * A logger for this class. - **/ - private static final Logger LOG = JmxProperties.NAMESPACE_LOGGER; - private static final Logger PROBE_LOG = Logger.getLogger( - JmxProperties.NAMESPACE_LOGGER+".probe"); // The target name space in which the NamepsaceHandler is mounted. private final String targetNs; @@ -69,21 +56,6 @@ public class NamespaceInterceptor extends HandlerInterceptor<JMXNamespace> { private final ObjectNameRouter proc; /** - * Internal hack. The JMXRemoteNamespace can be closed and reconnected. - * Each time the JMXRemoteNamespace connects, a probe should be sent - * to detect cycle. The MBeanServer exposed by JMXRemoteNamespace thus - * implements the DynamicProbe interface, which makes it possible for - * this handler to know that it should send a new probe. - * - * XXX: TODO this probe thing is way too complex and fragile. - * This *must* go away or be replaced by something simpler. - * ideas are welcomed. - **/ - public static interface DynamicProbe { - public boolean isProbeRequested(); - } - - /** * Creates a new instance of NamespaceInterceptor */ public NamespaceInterceptor( @@ -104,164 +76,6 @@ public class NamespaceInterceptor extends HandlerInterceptor<JMXNamespace> { ", namespace="+this.targetNs+")"; } - /* - * XXX: TODO this probe thing is way too complex and fragile. - * This *must* go away or be replaced by something simpler. - * ideas are welcomed. - */ - private volatile boolean probed = false; - private volatile ObjectName probe; - - // Query Pattern that we will send through the source server in order - // to detect self-linking namespaces. - // - // XXX: TODO this probe thing is way too complex and fragile. - // This *must* go away or be replaced by something simpler. - // ideas are welcomed. - final ObjectName makeProbePattern(ObjectName probe) - throws MalformedObjectNameException { - - // we could probably link the probe pattern with the probe - e.g. - // using the UUID as key in the pattern - but is it worth it? it - // also has some side effects on the context namespace - because - // such a probe may get rejected by the jmx.context// namespace. - // - // The trick here is to devise a pattern that is not likely to - // be blocked by intermediate levels. Querying for all namespace - // handlers in the source (or source namespace) is more likely to - // achieve this goal. - // - return ObjectName.getInstance("*" + - JMXNamespaces.NAMESPACE_SEPARATOR + ":" + - JMXNamespace.TYPE_ASSIGNMENT); - } - - // tell whether the name pattern corresponds to what might have been - // sent as a probe. - // XXX: TODO this probe thing is way too complex and fragile. - // This *must* go away or be replaced by something simpler. - // ideas are welcomed. - final boolean isProbePattern(ObjectName name) { - final ObjectName p = probe; - if (p == null) return false; - try { - return String.valueOf(name).endsWith(targetNs+ - JMXNamespaces.NAMESPACE_SEPARATOR + "*" + - JMXNamespaces.NAMESPACE_SEPARATOR + ":" + - JMXNamespace.TYPE_ASSIGNMENT); - } catch (RuntimeException x) { - // should not happen. - PROBE_LOG.finest("Ignoring unexpected exception in self link detection: "+ - x); - return false; - } - } - - // The first time a request reaches this NamespaceInterceptor, the - // interceptor will send a probe to detect whether the underlying - // JMXNamespace links to itslef. - // - // One way to create such self-linking namespace would be for instance - // to create a JMXNamespace whose getSourceServer() method would return: - // JMXNamespaces.narrowToNamespace(getMBeanServer(), - // getObjectName().getDomain()) - // - // If such an MBeanServer is returned, then any call to that MBeanServer - // will trigger an infinite loop. - // There can be even trickier configurations if remote connections are - // involved. - // - // In order to prevent this from happening, the NamespaceInterceptor will - // send a probe, in an attempt to detect whether it will receive it at - // the other end. If the probe is received, an exception will be thrown - // in order to break the recursion. The probe is only sent once - when - // the first request to the namespace occurs. The DynamicProbe interface - // can also be used by a Sun JMXNamespace implementation to request the - // emission of a probe at any time (see JMXRemoteNamespace - // implementation). - // - // Probes work this way: the NamespaceInterceptor sets a flag and sends - // a queryNames() request. If a queryNames() request comes in when the flag - // is on, then it deduces that there is a self-linking loop - and instead - // of calling queryNames() on the source MBeanServer of the JMXNamespace - // handler (which would cause the loop to go on) it breaks the recursion - // by returning the probe ObjectName. - // If the NamespaceInterceptor receives the probe ObjectName as result of - // its original sendProbe() request it knows that it has been looping - // back on itslef and throws an IOException... - // - // - // XXX: TODO this probe thing is way too complex and fragile. - // This *must* go away or be replaced by something simpler. - // ideas are welcomed. - // - final void sendProbe(MBeanServerConnection msc) - throws IOException { - try { - PROBE_LOG.fine("Sending probe"); - - // This is just to prevent any other thread to modify - // the probe while the detection cycle is in progress. - // - final ObjectName probePattern; - // we don't want to synchronize on this - we use targetNs - // because it's non null and final. - synchronized (targetNs) { - probed = false; - if (probe != null) { - throw new IOException("concurent connection in progress"); - } - final String uuid = UUID.randomUUID().toString(); - final String endprobe = - JMXNamespaces.NAMESPACE_SEPARATOR + uuid + - ":type=Probe,key="+uuid; - final ObjectName newprobe = - ObjectName.getInstance(endprobe); - probePattern = makeProbePattern(newprobe); - probe = newprobe; - } - - try { - PROBE_LOG.finer("Probe query: "+probePattern+" expecting: "+probe); - final Set<ObjectName> res = msc.queryNames(probePattern, null); - final ObjectName expected = probe; - PROBE_LOG.finer("Probe res: "+res); - if (res.contains(expected)) { - throw new IOException("namespace " + - targetNs + " is linking to itself: " + - "cycle detected by probe"); - } - } catch (SecurityException x) { - PROBE_LOG.finer("Can't check for cycles: " + x); - // can't do anything.... - } catch (RuntimeException x) { - PROBE_LOG.finer("Exception raised by queryNames: " + x); - throw x; - } finally { - probe = null; - } - } catch (MalformedObjectNameException x) { - final IOException io = - new IOException("invalid name space: probe failed"); - io.initCause(x); - throw io; - } - PROBE_LOG.fine("Probe returned - no cycles"); - probed = true; - } - - // allows a Sun implementation JMX Namespace, such as the - // JMXRemoteNamespace, to control when a probe should be sent. - // - // XXX: TODO this probe thing is way too complex and fragile. - // This *must* go away or be replaced by something simpler. - // ideas are welcomed. - private boolean isProbeRequested(Object o) { - if (o instanceof DynamicProbe) - return ((DynamicProbe)o).isProbeRequested(); - return false; - } - /** * This method will send a probe to detect self-linking name spaces. * A self linking namespace is a namespace that links back directly @@ -281,29 +95,9 @@ public class NamespaceInterceptor extends HandlerInterceptor<JMXNamespace> { * (see JMXRemoteNamespace implementation). */ private MBeanServer connection() { - try { - final MBeanServer c = super.source(); - if (probe != null) // should not happen - throw new RuntimeException("connection is being probed"); - - if (probed == false || isProbeRequested(c)) { - try { - // Should not happen if class well behaved. - // Never probed. Force it. - //System.err.println("sending probe for " + - // "target="+targetNs+", source="+srcNs); - sendProbe(c); - } catch (IOException io) { - throw new RuntimeException(io.getMessage(), io); - } - } - - if (c != null) { - return c; - } - } catch (RuntimeException x) { - throw x; - } + final MBeanServer c = super.source(); + if (c != null) return c; + // should not come here throw new NullPointerException("getMBeanServerConnection"); } @@ -319,24 +113,6 @@ public class NamespaceInterceptor extends HandlerInterceptor<JMXNamespace> { return super.source(); } - /** - * Calls {@link MBeanServerConnection#queryNames queryNames} - * on the underlying - * {@link #getMBeanServerConnection MBeanServerConnection}. - **/ - @Override - public final Set<ObjectName> queryNames(ObjectName name, QueryExp query) { - // XXX: TODO this probe thing is way too complex and fragile. - // This *must* go away or be replaced by something simpler. - // ideas are welcomed. - PROBE_LOG.finer("probe is: "+probe+" pattern is: "+name); - if (probe != null && isProbePattern(name)) { - PROBE_LOG.finer("Return probe: "+probe); - return Collections.singleton(probe); - } - return super.queryNames(name, query); - } - @Override protected ObjectName toSource(ObjectName targetName) throws MalformedObjectNameException { |