/*
 * @(#)BaseMetaDataImpl.java	1.14 03/12/19
 * 
 * Copyright 2004 Sun Microsystems, Inc. All rights reserved.
 * SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 */

package com.sun.jmx.mbeanserver;



// java import
import java.util.Iterator;
import java.io.PrintWriter;
import java.io.StringWriter;

// RI import
import javax.management.* ; 
import com.sun.jmx.trace.Trace; 

/**
 * The DynamicMetaDataImpl class provides local access to the metadata 
 * service in an agent. 
 * The DynamicMetaDataImpl only handles DynamicMBeans.
 *
 * @since 1.5
 * @since.unbundled JMX RI 1.2
 */
abstract class BaseMetaDataImpl implements MetaData {

    /** The name of this class to be used for tracing */
    private final static String dbgTag = "BaseMetaDataImpl";
    

    /**
     * Creates a Metadata Service.
     */
    BaseMetaDataImpl()  {

	// ------------------------------ 
	// ------------------------------ 
    } 

    
    //---------------------------------------------------------------------
    //
    // From the MetaData interface
    //
    //---------------------------------------------------------------------

    public abstract MBeanInfo getMBeanInfo(Object moi) 
	throws IntrospectionException;

    public abstract Object getAttribute(Object instance, String attribute)
	throws MBeanException, AttributeNotFoundException, 
	       ReflectionException;

    public abstract AttributeList getAttributes(Object instance, 
						String[] attributes) 
	throws ReflectionException;

    public abstract AttributeList setAttributes(Object instance, 
						AttributeList attributes) 
	throws ReflectionException;
    
    public abstract Object setAttribute(Object instance, Attribute attribute)  
	throws AttributeNotFoundException, InvalidAttributeValueException, 
	       MBeanException, ReflectionException;

    public abstract Object invoke(Object instance, String operationName, 
			 Object params[], String signature[]) 
	throws  MBeanException, ReflectionException;

    public ObjectName preRegisterInvoker(Object moi, ObjectName name, 
					 MBeanServer mbs) 
	throws InstanceAlreadyExistsException, MBeanRegistrationException {
   
	if (!(moi instanceof MBeanRegistration)) return name;

        final ObjectName newName;
      
        try {
            newName=(ObjectName)
		((MBeanRegistration)moi).preRegister(mbs, name);
        } catch (RuntimeException e) {
                throw new RuntimeMBeanException((RuntimeException)e, 
			   "RuntimeException thrown in preRegister method");       
	} catch (Error er) {      
                throw new RuntimeErrorException((Error) er, 
                           "Error thrown in preRegister method");
	} catch (MBeanRegistrationException r) {
	    throw (MBeanRegistrationException)r;
	} catch (Exception ex) {
	    throw new MBeanRegistrationException((Exception) ex, 
			  "Exception thrown in preRegister method");
	}      
        
	if (newName != null) return newName;
	else return name;
    }
   
    public void postRegisterInvoker(Object moi, boolean registrationDone) {
	if (!(moi instanceof MBeanRegistration)) return;

        try {
            ((MBeanRegistration)moi).
		postRegister(new Boolean(registrationDone));
        } catch (RuntimeException e) {
	    throw new RuntimeMBeanException((RuntimeException)e,  
		      "RuntimeException thrown in postRegister method");   
	} catch (Error er) {
	    throw new RuntimeErrorException((Error) er,  
		      "Error thrown in postRegister method");       
	}
    }
    
    public void preDeregisterInvoker(Object moi) 
	throws MBeanRegistrationException {
	if (!(moi instanceof MBeanRegistration)) return;

	try {
            ((MBeanRegistration)moi).preDeregister();
        } catch (RuntimeException e) {
	    throw new RuntimeMBeanException((RuntimeException) e,  
                         "RuntimeException thrown in preDeregister method");
	} catch (Error er) {         
	    throw new RuntimeErrorException((Error) er,  
                         "Error thrown in preDeregister method");     
	} catch (MBeanRegistrationException t) {
	    throw (MBeanRegistrationException)t;   
	} catch (Exception ex) {
	    throw new MBeanRegistrationException((Exception)ex,  
                         "Exception thrown in preDeregister method"); 
	}
    }
   
    public void postDeregisterInvoker(Object moi) {
	if (!(moi instanceof MBeanRegistration)) return;

        try {
            ((MBeanRegistration)moi).postDeregister();
        } catch (RuntimeException e) {
	    throw new RuntimeMBeanException((RuntimeException)e, 
                         "RuntimeException thrown in postDeregister method"); 
	} catch (Error er) {
	    throw new RuntimeErrorException((Error) er, 
                         "Error thrown in postDeregister method"); 
	} 
    }

    public String getMBeanClassName(Object moi) 
	throws IntrospectionException, NotCompliantMBeanException {

	final MBeanInfo mbi;
	try {
	    // Ask the MBeanInfo for the class name
	    mbi = getMBeanInfo(moi);
	} catch (SecurityException x) {
	    throw x;
	} catch (IntrospectionException x) {
	    throw x;
	} catch (Exception x) {
	    throw new NotCompliantMBeanException("Can't obtain MBeanInfo " +
						 "from DynamicMBean: " + x);
	}

	if (mbi == null) {
	    throw new 
		NotCompliantMBeanException("The MBeanInfo returned is null");
	}
	
	final String className = mbi.getClassName();
		
	if (className == null) {
	    throw new 
		IntrospectionException("The class Name returned is null");
	}

	return className;
    }

    public boolean isInstanceOf(Object instance, String className) 
	throws ReflectionException {

	try {
	    final String cn = getMBeanClassName(instance);
	    if (cn.equals(className))
		return true; 	    
	    try {
		final ClassLoader cl = instance.getClass().getClassLoader();
		
		final Class classNameClass = findClass(className,cl);
		if (classNameClass == null) return false;
		if (classNameClass.isInstance(instance)) return true;
		
		final Class instanceClass = findClass(cn,cl);
		if (instanceClass == null) return false;
		return classNameClass.isAssignableFrom(instanceClass);
	    } catch (Exception x) {
		/* Could be SecurityException or ClassNotFoundException */
		debugX("isInstanceOf",x);
		return false;
	    }
	} catch (IntrospectionException x) {
	    debugX("isInstanceOf",x);
	    throw new ReflectionException(x,x.getMessage());
	} catch (NotCompliantMBeanException x) {
	    debugX("isInstanceOf",x);
	    throw new ReflectionException(x,x.getMessage());
	}
    }

    protected Class findClass(String className, ClassLoader loader) 
	throws ReflectionException {
	try {
	    if (loader == null) 
		return Class.forName(className);
	    else 
		return loader.loadClass(className);
	} catch (ClassNotFoundException x) {
	    throw new ReflectionException(x,x.getMessage());
	}
    }

    // TRACES & DEBUG
    //---------------
    
    private static boolean isTraceOn() {
        return Trace.isSelected(Trace.LEVEL_TRACE, Trace.INFO_MBEANSERVER);
    }

    private static void trace(String clz, String func, String info) {
        Trace.send(Trace.LEVEL_TRACE, Trace.INFO_MBEANSERVER, clz, func, info);
    }
    
    private static void trace(String func, String info) {
        trace(dbgTag, func, info);
    }
    
    private static boolean isDebugOn() {
        return Trace.isSelected(Trace.LEVEL_DEBUG, Trace.INFO_MBEANSERVER);
    }
    
    private static void debug(String clz, String func, String info) {
        Trace.send(Trace.LEVEL_DEBUG, Trace.INFO_MBEANSERVER, clz, func, info);
    }
    
    private static void debug(String func, String info) {
        debug(dbgTag, func, info);
    }
    
    private static void debugX(String func,Throwable e) {
	if (isDebugOn()) {
	    final StringWriter s = new StringWriter();
	    e.printStackTrace(new PrintWriter(s));
	    final String stack = s.toString();
	    
	    debug(dbgTag,func,"Exception caught in "+ func+"(): "+e);
	    debug(dbgTag,func,stack);
	    // java.lang.System.err.println("**** Exception caught in "+
	    //			     func+"(): "+e);
	    // java.lang.System.err.println(stack);
	}
    }
 }