/*
 * JBoss, Home of Professional Open Source.
 * Copyright 2006, Red Hat Middleware LLC, and individual contributors
 * as indicated by the @author tags. See the copyright.txt file in the
 * distribution for a full listing of individual contributors.
 *
 * This is free software; you can redistribute it and/or modify it
 * under the terms of the GNU Lesser General Public License as
 * published by the Free Software Foundation; either version 2.1 of
 * the License, or (at your option) any later version.
 *
 * This software 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this software; if not, write to the Free
 * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
 * 02110-1301 USA, or see the FSF site: http://www.fsf.org.
 */
package javax.management.relation;

import org.jboss.mx.util.Serialization;

import javax.management.NotCompliantMBeanException;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.io.ObjectStreamField;
import java.io.Serializable;

/**
 * This class contains information about a role. For example the
 * number of mbean class name of the role, how many mbeans
 * are part of the role, whether the role is read/write, etc.<p>
 *
 * @author  <a href="mailto:Adrian.Brock@HappeningTimes.com">Adrian Brock</a>.
 * @author  <a href="mailto:thomas.diesler@jboss.com">Thomas Diesler</a>.
 *
 * @version $Revision: 57200 $
 */
public class RoleInfo
  implements Serializable
{
   // Constants ---------------------------------------------------

   /**
    * A value used to specify an infinite number of mbeans are allowed
    * in the role
    */
   public static int ROLE_CARDINALITY_INFINITY = -1;

   // Attributes --------------------------------------------------

   /**
    * The name of the role.
    */
   private String name;

   /**
    * The className of the MBeans in the role.
    */
   private String referencedMBeanClassName;

   /**
    * The readable attribute of the role.
    */
   boolean isReadable;

   /**
    * The writable attribute of the role.
    */
   boolean isWritable;

   /**
    * The minimum degree of the role.
    */
   int minDegree;

   /**
    * The maximum degree of the role.
    */
   int maxDegree;

   /**
    * The description of the role
    */
   String description;

   // Static ------------------------------------------------------

   private static final long serialVersionUID;
   private static final ObjectStreamField[] serialPersistentFields;

   static
   {
      switch (Serialization.version)
      {
      case Serialization.V1R0:
         serialVersionUID = 7227256952085334351L;
         serialPersistentFields = new ObjectStreamField[]
         {
            new ObjectStreamField("myDescription",  String.class),
            new ObjectStreamField("myIsReadableFlg", Boolean.TYPE),
            new ObjectStreamField("myIsWritableFlg", Boolean.TYPE),
            new ObjectStreamField("myMaxDegree", Integer.TYPE),
            new ObjectStreamField("myMinDegree", Integer.TYPE),
            new ObjectStreamField("myName", String.class),
            new ObjectStreamField("myRefMBeanClassName", String.class)
         };
         break;
      default:
         serialVersionUID = 2504952983494636987L;
         serialPersistentFields = new ObjectStreamField[]
         {
            new ObjectStreamField("description",  String.class),
            new ObjectStreamField("isReadable", Boolean.TYPE),
            new ObjectStreamField("isWritable", Boolean.TYPE),
            new ObjectStreamField("maxDegree", Integer.TYPE),
            new ObjectStreamField("minDegree", Integer.TYPE),
            new ObjectStreamField("name", String.class),
            new ObjectStreamField("referencedMBeanClassName", String.class)
         };
      }
   }

   // Constructors ------------------------------------------------

   /**
    * Copies the role info.
    *
    * @param other the role to copy.
    * @exception IllegalArgumentException for a null value.
    */
   public RoleInfo(RoleInfo other)
     throws IllegalArgumentException
   {
     if (other == null)
       throw new IllegalArgumentException("Null role info");
     this.name = other.name;
     this.referencedMBeanClassName = other.referencedMBeanClassName;
     this.isReadable = other.isReadable;
     this.isWritable = other.isWritable;
     this.minDegree = other.minDegree;
     this.maxDegree = other.maxDegree;
     this.description = other.description;
   }

   /**
    * Construct a role info with the given name and class name.
    * It is set to read/writable with a minimum and maximum degree of 1.
    * The description is null.
    *
    * @param name the name of the role.
    * @param className the name of the MBean class.
    * @exception IllegalArgumentException for a null value.
    * @exception ClassNotFoundException when the className does not exist.
    * @exception NotCompliantMBeanException when the className is not an
    *            mbean class.
    */
   public RoleInfo(String name, String className)
     throws IllegalArgumentException, ClassNotFoundException,
            NotCompliantMBeanException
   {
     this(name, className, true, true);
   }

   /**
    * Construct a role info with the given name, class name and
    * read/write attributes. It has a minimum and maximum degree of 1.
    * The description is null.
    *
    * @param name the name of the role.
    * @param className the name of the MBean class.
    * @param readable true for readable, false otherwise.
    * @param writable true for writable, false otherwise.
    * @exception IllegalArgumentException for a null value.
    * @exception ClassNotFoundException when the className does not exist.
    * @exception NotCompliantMBeanException when the className is not an
    *            mbean class.
    */
   public RoleInfo(String name, String className, boolean readable, boolean writable)
     throws IllegalArgumentException, ClassNotFoundException, NotCompliantMBeanException
   {
     if (name == null)
       throw new IllegalArgumentException("Null name");
     if (className == null)
       throw new IllegalArgumentException("Null class name");
     this.name = name;
     this.referencedMBeanClassName = className;
     this.isReadable = readable;
     this.isWritable = writable;
     minDegree = 1;
     maxDegree = 1;
   }

   /**
    * Construct a role info with the given name, class name,
    * read/write attributes, minimum/maximum degree and description.
    * The description can be null.<p>
    *
    * Pass <i>ROLE_CARDINALITY_INFINITY</i> for an unlimited degree.
    * The minimum must be less than or equal to the maximum.
    *
    * @param name the name of the role.
    * @param className the name of the MBean class.
    * @param readable true for readable, false otherwise.
    * @param writable true for writable, false otherwise.
    * @param minDegree the minimum degree.
    * @param maxDegree the maximum degree.
    * @param description the description.
    * @exception IllegalArgumentException for a null value.
    * @exception ClassNotFoundException when the className does not exist.
    * @exception NotCompliantMBeanException when the className is not an
    *            mbean class.
    * @exception InvalidRoleInfoException when the minimum degree is
    *            greater than the maximum.
    */
   public RoleInfo(String name, String className, boolean readable, boolean writable, int minDegree, int maxDegree, String description)
           throws IllegalArgumentException, ClassNotFoundException, NotCompliantMBeanException, InvalidRoleInfoException
   {
      if (name == null)
         throw new IllegalArgumentException("Null name");
      if (className == null)
         throw new IllegalArgumentException("Null class name");

      if (minDegree <  ROLE_CARDINALITY_INFINITY)
         throw new InvalidRoleInfoException("invalid minimum");
      if (maxDegree <  ROLE_CARDINALITY_INFINITY)
         throw new InvalidRoleInfoException("invalid maximum");
      if (maxDegree < minDegree && maxDegree != ROLE_CARDINALITY_INFINITY)
         throw new InvalidRoleInfoException("maximum less than minimum");
      if (minDegree == ROLE_CARDINALITY_INFINITY && maxDegree != ROLE_CARDINALITY_INFINITY)
         throw new InvalidRoleInfoException("maximum less than minimum");

      this.name = name;
      this.referencedMBeanClassName = className;
      this.minDegree = minDegree;
      this.maxDegree = maxDegree;
      this.isReadable = readable;
      this.isWritable = writable;
      this.description = description;
   }

   // Public ------------------------------------------------------

   /**
    * Check to see whether a given value is greater than or equal to the
    * minimum degree.
    *
    * @param value the value to check.
    * @return true when it is greater than or equal to the minimum degree,
    *         false otherwise.
    */
   public boolean checkMinDegree(int value)
   {
      if (minDegree == ROLE_CARDINALITY_INFINITY)
         return value >= ROLE_CARDINALITY_INFINITY;
      else
         return value >= minDegree;
   }

   /**
    * Check to see whether a given value is less than or equal to the
    * maximum degree.
    *
    * @param value the value to check.
    * @return true when it is less than or equal to the maximum degree,
    *         false otherwise.
    */
   public boolean checkMaxDegree(int value)
   {
      if(maxDegree == ROLE_CARDINALITY_INFINITY)
         return maxDegree >= ROLE_CARDINALITY_INFINITY;
      else
         return value <= maxDegree;
   }

   /**
    * Retrieve the description of the role.
    *
    * @return the description
    */
   public String getDescription()
   {
     return description;
   }

   /**
    * Retrieve the minimum degree.
    *
    * @return the minimum degree
    */
   public int getMinDegree()
   {
     return minDegree;
   }

   /**
    * Retrieve the maximum degree.
    *
    * @return the maximum degree
    */
   public int getMaxDegree()
   {
     return maxDegree;
   }

   /**
    * Retrieve the name of the role.
    *
    * @return the name
    */
   public String getName()
   {
     return name;
   }

   /**
    * Retrieve the class name of MBeans in this role.
    *
    * @return the class name
    */
   public String getRefMBeanClassName()
   {
     return referencedMBeanClassName;
   }

   /**
    * Retrieve the readable attribute.
    *
    * @return true for readable, false otherwise
    */
   public boolean isReadable()
   {
     return isReadable;
   }

   /**
    * Retrieve the writable attribute.
    *
    * @return true for writable, false otherwise
    */
   public boolean isWritable()
   {
     return isWritable;
   }

   // Object Overrides --------------------------------------------

   /**
    * Retrieve a string description of the role info.
    */
   public String toString()
   {
     StringBuffer buffer = new StringBuffer("RoleInfo for name: (");
     buffer.append(name);
     buffer.append(") class name: (");
     buffer.append(referencedMBeanClassName);
     buffer.append(") description: (");
     buffer.append(description);
     buffer.append(") readable: (");
     buffer.append(isReadable);
     buffer.append(") writable: (");
     buffer.append(isWritable);
     buffer.append(") minimum degree: (");
     buffer.append(minDegree);
     buffer.append(") maximum degree: (");
     buffer.append(maxDegree);
     buffer.append(")");
     return buffer.toString();
   }

   // Private -----------------------------------------------------

   private void readObject(ObjectInputStream ois)
      throws IOException, ClassNotFoundException
   {
      switch (Serialization.version)
      {
      case Serialization.V1R0:
         ObjectInputStream.GetField getField = ois.readFields();
         description = (String) getField.get("myDescription", null);
         isReadable = getField.get("myIsReadableFlg", false);
         isWritable = getField.get("myIsWritableFlg", false);
         maxDegree = getField.get("myMaxDegree", 1);
         minDegree = getField.get("myMinDegree", 1);
         name = (String) getField.get("myName", null);
         referencedMBeanClassName = (String) getField.get("myRefMBeanClassName", null);
         break;
      default:
         ois.defaultReadObject();
      }
   }

   private void writeObject(ObjectOutputStream oos)
      throws IOException
   {
      switch (Serialization.version)
      {
      case Serialization.V1R0:
         ObjectOutputStream.PutField putField = oos.putFields();
         putField.put("myDescription", description);
         putField.put("myIsReadableFlg", isReadable);
         putField.put("myIsWritableFlg", isWritable);
         putField.put("myMaxDegree", maxDegree);
         putField.put("myMinDegree", minDegree);
         putField.put("myName", name);
         putField.put("myRefMBeanClassName", referencedMBeanClassName);
         oos.writeFields();
         break;
      default:
         oos.defaultWriteObject();
      }
   }
}