costin 2003/03/12 23:05:19
Modified: modeler/src/java/org/apache/commons/modeler Registry.java
Log:
Start to add version info and deprecation and to clean up the method names.
Only few of the new methods will be "public" - a lot of stuff should be
considered experimental until it gets more review and use.
I also added a mechanism to support per/context class loader instantiation -
this will be important if modeler moves to the parent loader and we want
to support multiple versions of a component ( or to improve security )
Revision Changes Path
1.23 +169 -23
jakarta-commons/modeler/src/java/org/apache/commons/modeler/Registry.java
Index: Registry.java
===================================================================
RCS file:
/home/cvs/jakarta-commons/modeler/src/java/org/apache/commons/modeler/Registry.java,v
retrieving revision 1.22
retrieving revision 1.23
diff -u -r1.22 -r1.23
--- Registry.java 28 Feb 2003 21:24:35 -0000 1.22
+++ Registry.java 13 Mar 2003 07:05:18 -0000 1.23
@@ -73,6 +73,9 @@
import org.apache.commons.modeler.modules.ModelerSource;
/**
+ * This is the main entry point into modeler. It provides methods to manipulate
+ * the metadata used by the ModelMBeans and helpers to simplify the use.
+ *
* <p>Registry for MBean descriptor information. This class implements
* the Singleton design pattern.</p>
*
@@ -85,17 +88,22 @@
* @author Costin Manolache
*/
public final class Registry {
+
/**
* The Log instance to which we will write our log messages.
*/
private static Log log = LogFactory.getLog(Registry.class);
+
+ /** Will be used to isolate different apps and enhance security
+ */
+ private static HashMap perLoaderRegistries=null;
+
/**
* The registry instance created by our factory method the first time
* it is called.
*/
private static Registry registry = null;
-
/**
* The <code>MBeanServer</code> instance that we will use to register
* management beans.
@@ -117,26 +125,56 @@
/**
* Constructor to require use of the factory create method.
- * It is called from BaseRegistry
*/
protected Registry() {
-
super();
-
}
/**
* Factory method to create (if necessary) and return our
* <code>Registry</code> instance.
+ *
+ * Use this method to obtain a Registry - all other static methods
+ * are deprecated and shouldn't be used.
+ *
+ * The current version uses a static - future versions could use
+ * the thread class loader.
+ *
+ * @since 1.1
*/
public synchronized static Registry getRegistry() {
-
+ /* Experimental */
+ if( perLoaderRegistries!=null ) {
+ ClassLoader cl=Thread.currentThread().getContextClassLoader();
+ if( cl != null ) {
+ Registry localRegistry=(Registry)perLoaderRegistries.get(cl);
+ if( localRegistry != null ) return localRegistry;
+ localRegistry=new Registry();
+ perLoaderRegistries.put( cl, localRegistry );
+ return localRegistry;
+ }
+ }
if (registry == null) {
- log.debug("Creating new Registry instance");
registry = new Registry();
}
return (registry);
+ }
+ /** Experimental. Will allow containers to isolate apps
+ * @param enable
+ */
+ public void setUseContextClassLoader( boolean enable ) {
+ if( enable ) {
+ perLoaderRegistries=new HashMap();
+ }
+ }
+
+ /** Called by a registry or by the container to unload a loader
+ * @param loader
+ */
+ public void unregisterRegistry(ClassLoader loader ) {
+ // XXX Cleanup ?
+ perLoaderRegistries.remove(loader);
}
// -------------------- Metadata --------------------
@@ -148,7 +186,6 @@
* @since 1.0
*/
public void addManagedBean(ManagedBean bean) {
- // called from digester
// XXX Use group + name
descriptors.put(bean.getName(), bean);
if( bean.getType() != null ) {
@@ -161,11 +198,12 @@
* Find and return the managed bean definition for the specified
* bean name, if any; otherwise return <code>null</code>.
*
- * @param name Name of the managed bean to be returned
+ * @param name Name of the managed bean to be returned. Since 1.1, both
+ * short names or the full name of the class can be used.
* @since 1.0
- * XXX Group ?? Use Group + Type
*/
public ManagedBean findManagedBean(String name) {
+ // XXX Group ?? Use Group + Type
ManagedBean mb=((ManagedBean) descriptors.get(name));
if( mb==null )
mb=(ManagedBean)descriptorsByClass.get(name);
@@ -178,7 +216,6 @@
* this registry.
*
* @since 1.0
- * XXX Use the group
*/
public String[] findManagedBeans() {
return ((String[]) descriptors.keySet().toArray(new String[0]));
@@ -216,9 +253,9 @@
*
* @param bean The managed bean to be removed
* @since 1.0
- * TODO: change this to use group/name
*/
public void removeManagedBean(ManagedBean bean) {
+ // TODO: change this to use group/name
descriptors.remove(bean.getName());
descriptorsByClass.remove( bean.getType());
}
@@ -253,7 +290,7 @@
* registered management beans.
*
* @param server The new <code>MBeanServer</code> instance
- * @since 2.0
+ * @since 1.1
*/
public void setMBeanServer( MBeanServer server ) {
this.server=server;
@@ -263,7 +300,7 @@
* Factory method to create (if necessary) and return our
* <code>MBeanServer</code> instance.
*
- * @since 2.0
+ * @since 1.1
*/
public synchronized MBeanServer getMBeanServer() {
long t1=System.currentTimeMillis();
@@ -271,10 +308,12 @@
if (server == null) {
if( MBeanServerFactory.findMBeanServer(null).size() > 0 ) {
server=(MBeanServer)MBeanServerFactory.findMBeanServer(null).get(0);
- log.debug("Using existing MBeanServer " +
(System.currentTimeMillis() - t1 ));
+ if( log.isDebugEnabled() )
+ log.debug("Using existing MBeanServer " +
(System.currentTimeMillis() - t1 ));
} else {
server=MBeanServerFactory.createMBeanServer();
- log.debug("Creating MBeanServer"+ (System.currentTimeMillis() - t1
));
+ if( log.isDebugEnabled() )
+ log.debug("Creating MBeanServer"+ (System.currentTimeMillis() -
t1 ));
}
}
return (server);
@@ -303,18 +342,46 @@
* Load the registry from the XML input found in the specified input
* stream.
*
- * @param type The type of information to load. A name of a bean or
- * a local type.
- * @param source InputStream or URL to be loaded
+ * @param source Source to be used to load. Can be an InputStream or URL.
*
* @exception Exception if any parsing or processing error occurs
- * @since 2.0
+ * @since 1.1
+ */
+ public void loadDescriptors( Object source )
+ throws Exception
+ {
+ loadDescriptors("MbeansDescriptorsDOMSource", source, null );
+ }
+
+ /**
+ * Load the registry from a cached .ser file. This is typically 2-3 times
+ * faster than parsing the XML.
+ *
+ * @param source Source to be used to load. Can be an InputStream or URL.
+ *
+ * @exception Exception if any parsing or processing error occurs
+ * @since 1.1
+ */
+ public void loadCachedDescriptors( Object source )
+ throws Exception
+ {
+ loadDescriptors("MbeansDescriptorsSerSource", source, null );
+ }
+
+ /** Experimental. Will become private, some code may still use it
+ *
+ * @param sourceType
+ * @param source
+ * @param param
+ * @throws Exception
+ * @deprecated
*/
public void loadDescriptors( String sourceType, Object source, String param)
throws Exception
{
List mbeans=load( sourceType, source, param );
if( mbeans == null) return;
+
Iterator itr=mbeans.iterator();
while( itr.hasNext() ) {
Object mb=itr.next();
@@ -324,6 +391,28 @@
}
}
+ /** Load an extended mlet file. A similar syntax is supported by the
+ * ant tasks.
+ *
+ * @param source InputStream or URL of the file
+ * @return List of ObjectName for the loaded mbeans
+ * @throws Exception
+ * @since 1.1
+ */
+ public List loadMBeans( Object source )
+ throws Exception
+ {
+ return load("MBeansSource", source, null );
+ }
+
+ /** Experimental.
+ *
+ * @param sourceType
+ * @param source
+ * @param param
+ * @return
+ * @throws Exception
+ */
public List load( String sourceType, Object source, String param)
throws Exception
{
@@ -349,6 +438,15 @@
return mbeans;
}
+ /** Invoke a operation on a list of mbeans. Can be used to implement
+ * lifecycle operations.
+ *
+ * @param mbeans list of ObjectName on which we'll invoke the operations
+ * @param operation Name of the operation ( init, start, stop, etc)
+ * @param failFirst If false, exceptions will be ignored
+ * @throws Exception
+ * @since 1.1
+ */
public void invoke( List mbeans, String operation, boolean failFirst )
throws Exception
{
@@ -379,6 +477,8 @@
// -------------------- Instance registration --------------------
+ /** @deprecated - may still be used in code using unstable builds
+ */
public void registerComponent(Object bean, String domain, String type,
String name)
throws Exception
@@ -393,9 +493,22 @@
/** Main registration method
*
- * If the metadata is not found, introspection will be used to generate
+ * If metadata is not loaded, we'll look up for a file named
+ * mbeans-descriptors.ser or "mbeans-descriptors.xml" in the same package
+ * or parent.
+ *
+ * If the metadata is still not found, introspection will be used to generate
* it automatically.
*
+ * If the mbean is already registered under this name, it'll be first
+ * unregistered.
+ *
+ * @param bean Object to be registered
+ * @param oname Name used for registration
+ * @param type The type of the mbean, as declared in mbeans-descriptors. If
+ * null, the name of the class will be used.
+ *
+ * @since 1.1
*/
public void registerComponent(Object bean, ObjectName oname, String type)
throws Exception
@@ -405,17 +518,23 @@
log.error("Null component " + oname );
return;
}
+
try {
if( type==null ) {
type=bean.getClass().getName();
}
+
ManagedBean managed = registry.findManagedBean(type);
+
if( managed==null ) {
// check package and parent packages
findDescriptor( bean );
+
managed=findManagedBean(type);
// TODO: check super-class
}
+
+ // Still not found - use introspection
if( managed==null ) {
// introspection
loadDescriptors("MbeansDescriptorsIntrospectionSource",
@@ -442,6 +561,22 @@
}
}
+ /** Unregister a component. This is just a helper that
+ * avoids exceptions by checking if the mbean is already registered
+ *
+ * @param oname
+ * @since 1.1
+ */
+ public void unregisterComponent( ObjectName oname ) {
+ try {
+ if( getMBeanServer().isRegistered(oname))
+ getMBeanServer().unregisterMBean(oname);
+ } catch( Throwable t ) {
+ log.error( "Error unregistering mbean ", t);
+ }
+ }
+
+ // should be removed
public void unregisterComponent( String domain, String name ) {
try {
ObjectName oname=new ObjectName( domain + ":" + name );
@@ -454,6 +589,14 @@
}
// -------------------- Helpers --------------------
+
+ /** Get the type of an attribute of the object, from the metadata.
+ *
+ * @param oname
+ * @param attName
+ * @return null if metadata about the attribute is not found
+ * @since 1.1
+ */
public String getType( ObjectName oname, String attName )
{
String type=null;
@@ -461,9 +604,10 @@
try {
info=server.getMBeanInfo(oname);
} catch (Exception e) {
- log.info( "Can't find metadata " + oname );
+ log.info( "Can't find metadata for object" + oname );
return null;
}
+
MBeanAttributeInfo attInfo[]=info.getAttributes();
for( int i=0; i<attInfo.length; i++ ) {
if( attName.equals(attInfo[i].getName())) {
@@ -494,6 +638,8 @@
}
// -------------------- Experimental: discovery --------------------
+ /** Experimental support for manifest-based discovery.
+ */
public static String MODELER_MANIFEST="/META-INF/modeler-mbeans.xml";
/** Discover all META-INF/modeler.xml files in classpath and register
@@ -520,11 +666,11 @@
// Store all objects that have been registered via modeler
// it is used to generate unique names automatically - using seq=
// scheme
- Hashtable instances=new Hashtable();
+ private Hashtable instances=new Hashtable();
/**
* Help manage multiple instances with the same name prefix.
- *
+ * @since experimental
*/
public int generateSeqNumber(String name) {
//String name=getType( domain, realClass );
---------------------------------------------------------------------
To unsubscribe, e-mail: [EMAIL PROTECTED]
For additional commands, e-mail: [EMAIL PROTECTED]
