All Implemented Interfaces:

Serializable, ValueExp

public class AttributeValueExp
extends Object
implements ValueExp 

Since:

1.5

See Also:

Serialized Form

• Constructor Summary

  Constructors

  Constructor	Description
  AttributeValueExp ()	Deprecated. An instance created with this constructor cannot be used in a query.
  AttributeValueExp (String attr)	Creates a new AttributeValueExp representing the specified object attribute, named attr.

• Method Summary

  All Methods

  Modifier and Type	Method	Description
  ValueExp	apply (ObjectName name)	Applies the AttributeValueExp on an MBean.
  protected Object	getAttribute (ObjectName name)	Return the value of the given attribute in the named MBean.
  String	getAttributeName ()	Returns a string representation of the name of the attribute.
  void	setMBeanServer (MBeanServer s)	Deprecated. This method has no effect. The MBean Server used to obtain an attribute value is QueryEval.getMBeanServer().
  String	toString ()	Returns the string representing its value.

  • Methods inherited from class java.lang.Object

    clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

• Constructor Detail

  • AttributeValueExp

    @Deprecated
    public AttributeValueExp()

    Deprecated. An instance created with this constructor cannot be used in a query.
    An AttributeValueExp with a null attribute.

  • AttributeValueExp

    public AttributeValueExp(String attr)

    Creates a new AttributeValueExp representing the specified object attribute, named attr.

    Parameters:

    attr - the name of the attribute whose value is the value of this ValueExp.

• Method Detail

  • getAttributeName

    public String getAttributeName()

    Returns a string representation of the name of the attribute.

    Returns:

    the attribute name.

  • apply

    public ValueExp apply(ObjectName name)
     throws BadStringOperationException,
     BadBinaryOpValueExpException,
     BadAttributeValueExpException,
     InvalidApplicationException 

    Applies the AttributeValueExp on an MBean. This method calls getAttribute(name) and wraps the result as a ValueExp. The value returned by getAttribute must be a Number, String, or Boolean; otherwise this method throws a BadAttributeValueExpException, which will cause the containing query to be false for this name.

    Specified by:

    apply in interface ValueExp

    Parameters:

    name - The name of the MBean on which the AttributeValueExp will be applied.

    Returns:

    The ValueExp.

    Throws:

    BadAttributeValueExpException

    InvalidApplicationException

    BadStringOperationException

    BadBinaryOpValueExpException

  • toString

    public String toString()

    Returns the string representing its value.

    Overrides:

    toString in class Object

    Returns:

    a string representation of the object.

  • setMBeanServer

    @Deprecated
    public void setMBeanServer(MBeanServer s)

    Deprecated. This method has no effect. The MBean Server used to obtain an attribute value is QueryEval.getMBeanServer().
    Sets the MBean server on which the query is to be performed.

    Specified by:

    setMBeanServer in interface ValueExp

    Parameters:

    s - The MBean server on which the query is to be performed.

  • getAttribute

    protected Object getAttribute(ObjectName name)

    Return the value of the given attribute in the named MBean. If the attempt to access the attribute generates an exception, return null.

    The MBean Server used is the one returned by QueryEval.getMBeanServer().

    Parameters:

    name - the name of the MBean whose attribute is to be returned.

    Returns:

    the value of the attribute, or null if it could not be obtained.