package net.sf.snmpadaptor4j.core.accessor;

 import javax.management.MBeanServer;

 import javax.management.ObjectName;

 import javax.management.openmbean.CompositeData;

 import net.sf.snmpadaptor4j.api.AttributeAccessor;

 import net.sf.snmpadaptor4j.object.SnmpDataType;

 import net.sf.snmpadaptor4j.object.SnmpOid;

 /**

  * Object representing an accessor to an attribute for {@link CompositeData}.

  * @author <a href="http://fr.linkedin.com/in/jpminetti/">Jean-Philippe MINETTI</a>

  */

 public final class CompositeDataAttributeAccessor

                 implements AttributeAccessor {

         /**

          * <b>O</b>bject <b>ID</b>entifier (OID) to locate the attribute in the MIB.

          */

         private final SnmpOid oid;

         /**

          * JMX agent where the MBean was registered.

          */

         private final MBeanServer server;

         /**

          * MBean name.

          */

         private final ObjectName mBeanName;

         /**

          * Attribute name of {@link CompositeData}.

          */

         private final String attributeName;

         /**

          * Attribute key of value.

          */

         private final String attributeKey;

         /**

          * SNMP data type of attribute.

          */

         private final SnmpDataType snmpDataType;

         /**

          * Data type of JMX attribute.

          */

         private final Class<?> jmxDataType;

         /**

          * Constructor.

          * @param oid <b>O</b>bject <b>ID</b>entifier (OID) to locate the attribute in the MIB.

          * @param server JMX agent where the MBean was registered.

          * @param mBeanName MBean name.

          * @param attributeName Attribute name of {@link CompositeData}.

          * @param attributeKey Attribute key of value.

          * @param snmpDataType SNMP data type of attribute.

          * @param jmxDataType Data type of JMX attribute.

          */

         public CompositeDataAttributeAccessor (final SnmpOid oid, final MBeanServer server, final ObjectName mBeanName, final String attributeName,

                         final String attributeKey, final SnmpDataType snmpDataType, final Class<?> jmxDataType) {

                 super();

                 this.oid = oid;

                 this.server = server;

                 this.mBeanName = mBeanName;

                 this.attributeName = attributeName;

                 this.attributeKey = attributeKey;

                 this.snmpDataType = snmpDataType;

                 this.jmxDataType = jmxDataType;

         }

         /*

          * {@inheritDoc}

          * @see net.sf.snmpadaptor4j.api.AttributeAccessor#getOid()

          */

         public SnmpOid getOid () {

                 return this.oid;

         }

         /*

          * {@inheritDoc}

          * @see net.sf.snmpadaptor4j.api.AttributeAccessor#getSnmpDataType()

          */

         public SnmpDataType getSnmpDataType () {

                 return this.snmpDataType;

         }

         /*

          * {@inheritDoc}

          * @see net.sf.snmpadaptor4j.api.AttributeAccessor#getJmxDataType()

          */

         public Class<?> getJmxDataType () {

                 return this.jmxDataType;

         }

         /*

          * {@inheritDoc}

          * @see net.sf.snmpadaptor4j.api.AttributeAccessor#getValue()

          */

         public Object getValue () throws Exception {

                 Object value = null;

                 final CompositeData compositeData = (CompositeData) this.server.getAttribute(this.mBeanName, this.attributeName);

                 if (compositeData != null) {

                         value = compositeData.get(this.attributeKey);

                 }

                 return value;

         }

         /*

          * {@inheritDoc}

          * @see net.sf.snmpadaptor4j.api.AttributeAccessor#setValue(java.lang.Object)

          */

         public void setValue (final Object value) {

                 // NOP

         }

         /*

          * {@inheritDoc}

          * @see net.sf.snmpadaptor4j.api.AttributeAccessor#isReadable()

          */

         public boolean isReadable () {

                 return true;

         }

         /*

          * {@inheritDoc}

          * @see net.sf.snmpadaptor4j.api.AttributeAccessor#isWritable()

          */

         public boolean isWritable () {

                 return false;

         }

         /*

          * {@inheritDoc}

          * @see java.lang.Object#toString()

          */

         @Override

         public String toString () {

                 Object value;

                 try {

                         value = getValue();

                 }

                 catch (final Throwable e) {

                         value = "ERROR: " + (e.getMessage() != null ? e.getMessage() : e.getClass().getName());

                 }

                 return this.oid + ": (" + getSnmpDataType() + ") " + value;

         }

 }