/*

 * Copyright 2000-2008 Sun Microsystems, Inc.  All Rights Reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.  Sun designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Sun in the LICENSE file that accompanied this code.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,

 * CA 95054 USA or visit www.sun.com if you need additional information or

 * have any questions.

 */

package com.sun.jmx.mbeanserver;

import static com.sun.jmx.defaults.JmxProperties.MBEANSERVER_LOGGER;

import java.io.ByteArrayInputStream;

import java.io.IOException;

import java.io.ObjectInputStream;

import java.lang.reflect.Constructor;

import java.lang.reflect.InvocationTargetException;

import java.util.Map;

import java.util.logging.Level;

import javax.management.InstanceNotFoundException;

import javax.management.MBeanException;

import javax.management.NotCompliantMBeanException;

import javax.management.ObjectName;

import javax.management.OperationsException;

import javax.management.ReflectionException;

import javax.management.RuntimeErrorException;

import javax.management.RuntimeMBeanException;

import javax.management.RuntimeOperationsException;

import sun.reflect.misc.ReflectUtil;

/**

 * Implements the MBeanInstantiator interface. Provides methods for

 * instantiating objects, finding the class given its name and using

 * different class loaders, deserializing objects in the context of a

 * given class loader.

 *

 * @since 1.5

 */

public class MBeanInstantiator {

    private final ModifiableClassLoaderRepository clr;

    //    private MetaData meta = null;

    MBeanInstantiator(ModifiableClassLoaderRepository clr) {

        this.clr = clr;

    }

    /**

     * This methods tests if the MBean class makes it possible to

     * instantiate an MBean of this class in the MBeanServer.

     * e.g. it must have a public constructor, be a concrete class...

     */

    public void testCreation(Class<?> c) throws NotCompliantMBeanException {

        Introspector.testCreation(c);

    }

    /**

     * Loads the class with the specified name using this object's

     * Default Loader Repository.

     **/

    public Class<?> findClassWithDefaultLoaderRepository(String className)

        throws ReflectionException {

        Class<?> theClass;

        if (className == null) {

            throw new RuntimeOperationsException(new

                IllegalArgumentException("The class name cannot be null"),

                             "Exception occurred during object instantiation");

        }

        try {

            if (clr == null) throw new ClassNotFoundException(className);

            theClass = clr.loadClass(className);

        }

        catch (ClassNotFoundException ee) {

            throw new ReflectionException(ee,

       "The MBean class could not be loaded by the default loader repository");

        }

        return theClass;

    }

    /**

     * Gets the class for the specified class name using the MBean

     * Interceptor's classloader

     */

    public Class<?> findClass(String className, ClassLoader loader)

        throws ReflectionException {

        return loadClass(className,loader);

    }

    /**

     * Gets the class for the specified class name using the specified

     * class loader

     */

    public Class<?> findClass(String className, ObjectName aLoader)

        throws ReflectionException, InstanceNotFoundException  {

        if (aLoader == null)

            throw new RuntimeOperationsException(new

                IllegalArgumentException(), "Null loader passed in parameter");

        // Retrieve the class loader from the repository

        ClassLoader loader = null;

        synchronized(this) {

            if (clr!=null)

                loader = clr.getClassLoader(aLoader);

        }

        if (loader == null) {

            throw new InstanceNotFoundException("The loader named " +

                       aLoader + " is not registered in the MBeanServer");

        }

        return findClass(className,loader);

    }

    /**

     * Return an array of Class corresponding to the given signature, using

     * the specified class loader.

     */

    public Class<?>[] findSignatureClasses(String signature[],

                                           ClassLoader loader)

        throws ReflectionException {

        if (signature == null) return null;

        final ClassLoader aLoader = loader;

        final int length= signature.length;

        final Class<?> tab[]=new Class<?>[length];

        if (length == 0) return tab;

        try {

            for (int i= 0; i < length; i++) {

                // Start handling primitive types (int. boolean and so

                // forth)

                //

                final Class<?> primCla = primitiveClasses.get(signature[i]);

                if (primCla != null) {

                    tab[i] = primCla;

                    continue;

                }

                // Ok we do not have a primitive type ! We need to build

                // the signature of the method

                //

                if (aLoader != null) {

                    // We need to load the class through the class

                    // loader of the target object.

                    //

                    tab[i] = Class.forName(signature[i], false, aLoader);

                } else {

                    // Load through the default class loader

                    //

                    tab[i] = findClass(signature[i],

                                       this.getClass().getClassLoader());

                }

            }

        } catch (ClassNotFoundException e) {

            if (MBEANSERVER_LOGGER.isLoggable(Level.FINEST)) {

                MBEANSERVER_LOGGER.logp(Level.FINEST,

                        MBeanInstantiator.class.getName(),

                        "findSignatureClasses",

                        "The parameter class could not be found", e);

            }

            throw new ReflectionException(e,

                      "The parameter class could not be found");

        } catch (RuntimeException e) {

            if (MBEANSERVER_LOGGER.isLoggable(Level.FINEST)) {

                MBEANSERVER_LOGGER.logp(Level.FINEST,

                        MBeanInstantiator.class.getName(),

                        "findSignatureClasses",

                        "Unexpected exception", e);

            }

            throw e;

        }

        return tab;

    }

    /**

     * Instantiates an object given its class, using its empty constructor.

     * The call returns a reference to the newly created object.

     */

    public Object instantiate(Class<?> theClass)

        throws ReflectionException, MBeanException {

        Object moi;

        // ------------------------------

        // ------------------------------

        Constructor<?> cons = findConstructor(theClass, null);

        if (cons == null) {

            throw new ReflectionException(new

                NoSuchMethodException("No such constructor"));

        }

        // Instantiate the new object

        try {

            ReflectUtil.checkPackageAccess(theClass);

            moi= cons.newInstance();

        } catch (InvocationTargetException e) {

            // Wrap the exception.

            Throwable t = e.getTargetException();

            if (t instanceof RuntimeException) {

                throw new RuntimeMBeanException((RuntimeException)t,

                   "RuntimeException thrown in the MBean's empty constructor");

            } else if (t instanceof Error) {

                throw new RuntimeErrorException((Error) t,

                   "Error thrown in the MBean's empty constructor");

            } else {

                throw new MBeanException((Exception) t,

                   "Exception thrown in the MBean's empty constructor");

            }

        } catch (NoSuchMethodError error) {

            throw new ReflectionException(new

                NoSuchMethodException("No constructor"),

                                          "No such constructor");

        } catch (InstantiationException e) {

            throw new ReflectionException(e,

            "Exception thrown trying to invoke the MBean's empty constructor");

        } catch (IllegalAccessException e) {

            throw new ReflectionException(e,

            "Exception thrown trying to invoke the MBean's empty constructor");

        } catch (IllegalArgumentException e) {

            throw new ReflectionException(e,

            "Exception thrown trying to invoke the MBean's empty constructor");

        }

        return moi;

    }

   /**

     * Instantiates an object given its class, the parameters and

     * signature of its constructor The call returns a reference to

     * the newly created object.

     */

    public Object instantiate(Class<?> theClass, Object params[],

                              String signature[], ClassLoader loader)

        throws ReflectionException, MBeanException {

        // Instantiate the new object

        // ------------------------------

        // ------------------------------

        final Class<?>[] tab;

        Object moi;

        try {

            // Build the signature of the method

            //

            ClassLoader aLoader= theClass.getClassLoader();

            // Build the signature of the method

            //

            tab =

                ((signature == null)?null:

                 findSignatureClasses(signature,aLoader));

        }

        // Exception IllegalArgumentException raised in Jdk1.1.8

        catch (IllegalArgumentException e) {

            throw new ReflectionException(e,

                    "The constructor parameter classes could not be loaded");

        }

        // Query the metadata service to get the right constructor

        Constructor<?> cons = findConstructor(theClass, tab);

        if (cons == null) {

            throw new ReflectionException(new

                NoSuchMethodException("No such constructor"));

        }

        try {

            ReflectUtil.checkPackageAccess(theClass);

            moi = cons.newInstance(params);

        }

        catch (NoSuchMethodError error) {

            throw new ReflectionException(new

                NoSuchMethodException("No such constructor found"),

                                          "No such constructor" );

        }

        catch (InstantiationException e) {

            throw new ReflectionException(e,

                "Exception thrown trying to invoke the MBean's constructor");

        }

        catch (IllegalAccessException e) {

            throw new ReflectionException(e,

                "Exception thrown trying to invoke the MBean's constructor");

        }

        catch (InvocationTargetException e) {

            // Wrap the exception.

            Throwable th = e.getTargetException();

            if (th instanceof RuntimeException) {

                throw new RuntimeMBeanException((RuntimeException)th,

                      "RuntimeException thrown in the MBean's constructor");

            } else if (th instanceof Error) {

                throw new RuntimeErrorException((Error) th,

                      "Error thrown in the MBean's constructor");

            } else {

                throw new MBeanException((Exception) th,

                      "Exception thrown in the MBean's constructor");

            }

        }

        return moi;

    }

    /**

     * De-serializes a byte array in the context of a classloader.

     *

     * @param loader the classloader to use for de-serialization

     * @param data The byte array to be de-sererialized.

     *

     * @return  The de-serialized object stream.

     *

     * @exception OperationsException Any of the usual Input/Output related

     * exceptions.

     */

    public ObjectInputStream deserialize(ClassLoader loader, byte[] data)

        throws OperationsException {

        // Check parameter validity

        if (data == null) {

            throw new  RuntimeOperationsException(new

                IllegalArgumentException(), "Null data passed in parameter");

        }

        if (data.length == 0) {

            throw new  RuntimeOperationsException(new

                IllegalArgumentException(), "Empty data passed in parameter");

        }

        // Object deserialization

        ByteArrayInputStream bIn;

        ObjectInputStream    objIn;

        bIn   = new ByteArrayInputStream(data);

        try {

            objIn = new ObjectInputStreamWithLoader(bIn,loader);

        } catch (IOException e) {

            throw new OperationsException(

                     "An IOException occurred trying to de-serialize the data");

        }

        return objIn;

    }

    /**

     * De-serializes a byte array in the context of a given MBean class loader.

     * <P>The class loader is the one that loaded the class with name

     * "className".

     * <P>The name of the class loader to be used for loading the specified

     * class is specified. If null, a default one has to be provided (for a

     * MBean Server, its own class loader will be used).

     *

     * @param className The name of the class whose class loader should

     *  be used for the de-serialization.

     * @param data The byte array to be de-sererialized.

     * @param loaderName The name of the class loader to be used for loading

     * the specified class. If null, a default one has to be provided (for a

     * MBean Server, its own class loader will be used).

     *

     * @return  The de-serialized object stream.

     *

     * @exception InstanceNotFoundException The specified class loader MBean is

     * not found.

     * @exception OperationsException Any of the usual Input/Output related

     * exceptions.

     * @exception ReflectionException The specified class could not be loaded

     * by the specified class loader.

     */

    public ObjectInputStream deserialize(String className,

                                         ObjectName loaderName,

                                         byte[] data,

                                         ClassLoader loader)

        throws InstanceNotFoundException,

               OperationsException,

               ReflectionException  {

        // Check parameter validity

        if (data == null) {

            throw new  RuntimeOperationsException(new

                IllegalArgumentException(), "Null data passed in parameter");

        }

        if (data.length == 0) {

            throw new  RuntimeOperationsException(new

                IllegalArgumentException(), "Empty data passed in parameter");

        }

        if (className == null) {

            throw new  RuntimeOperationsException(new

             IllegalArgumentException(), "Null className passed in parameter");

        }

        Class<?> theClass;

        if (loaderName == null) {

            // Load the class using the agent class loader

            theClass = findClass(className, loader);

        } else {

            // Get the class loader MBean

            try {

                ClassLoader instance = null;

                if (clr!=null)

                    instance = clr.getClassLoader(loaderName);

                if (instance == null)

                    throw new ClassNotFoundException(className);

                theClass = Class.forName(className, false, instance);

            }

            catch (ClassNotFoundException e) {

                throw new ReflectionException(e,

                               "The MBean class could not be loaded by the " +

                               loaderName.toString() + " class loader");

            }

        }

        // Object deserialization

        ByteArrayInputStream bIn;

        ObjectInputStream    objIn;

        bIn   = new ByteArrayInputStream(data);

        try {

            objIn = new ObjectInputStreamWithLoader(bIn,

                                           theClass.getClassLoader());

        } catch (IOException e) {

            throw new OperationsException(

                    "An IOException occurred trying to de-serialize the data");

        }

        return objIn;

    }

    /**

     * Instantiates an object using the list of all class loaders registered

     * in the MBean Interceptor

     * (using its {@link javax.management.loading.ClassLoaderRepository}).

     * <P>The object's class should have a public constructor.

     * <P>It returns a reference to the newly created object.

     * <P>The newly created object is not registered in the MBean Interceptor.

     *

     * @param className The class name of the object to be instantiated.

     *

     * @return The newly instantiated object.

     *

     * @exception ReflectionException Wraps a

     * <CODE>java.lang.ClassNotFoundException</CODE> or the

     * <CODE>java.lang.Exception</CODE> that occurred when trying to invoke the

     * object's constructor.

     * @exception MBeanException The constructor of the object has thrown an

     * exception

     * @exception RuntimeOperationsException Wraps a

     * <CODE>java.lang.IllegalArgumentException</CODE>: the className passed in

     * parameter is null.

     */

    public Object instantiate(String className)

        throws ReflectionException,

        MBeanException {

        return instantiate(className, (Object[]) null, (String[]) null, null);

    }

    /**

     * Instantiates an object using the class Loader specified by its

     * <CODE>ObjectName</CODE>.

     * <P>If the loader name is null, a default one has to be provided (for a

     * MBean Server, the ClassLoader that loaded it will be used).

     * <P>The object's class should have a public constructor.

     * <P>It returns a reference to the newly created object.

     * <P>The newly created object is not registered in the MBean Interceptor.

     *

     * @param className The class name of the MBean to be instantiated.

     * @param loaderName The object name of the class loader to be used.

     *

     * @return The newly instantiated object.

     *

     * @exception ReflectionException Wraps a

     * <CODE>java.lang.ClassNotFoundException</CODE> or the

     * <CODE>java.lang.Exception</CODE> that occurred when trying to invoke the

     * object's constructor.

     * @exception MBeanException The constructor of the object has thrown an

     * exception.

     * @exception InstanceNotFoundException The specified class loader is not

     * registered in the MBeanServerInterceptor.

     * @exception RuntimeOperationsException Wraps a

     * <CODE>java.lang.IllegalArgumentException</CODE>: the className passed in

     * parameter is null.

     */

    public Object instantiate(String className, ObjectName loaderName,

                              ClassLoader loader)

        throws ReflectionException, MBeanException,

               InstanceNotFoundException {

        return instantiate(className, loaderName, (Object[]) null,

                           (String[]) null, loader);

    }

    /**

     * Instantiates an object using the list of all class loaders registered

     * in the MBean server

     * (using its {@link javax.management.loading.ClassLoaderRepository}).

     * <P>The object's class should have a public constructor.

     * <P>The call returns a reference to the newly created object.

     * <P>The newly created object is not registered in the MBean Interceptor.

     *

     * @param className The class name of the object to be instantiated.