MBeanServerDelegateImpl.java 文件源码

/**
 * This method always fail since all MBeanServerDelegateMBean attributes
 * are read-only.
 *
 * @param attribute The identification of the attribute to
 * be set and  the value it is to be set to.
 *
 * @exception AttributeNotFoundException
 */
public void setAttribute(Attribute attribute)
    throws AttributeNotFoundException, InvalidAttributeValueException,
           MBeanException, ReflectionException {

    // Now we will always fail:
    // Either because the attribute is null or because it is not
    // accessible (or does not exist).
    //
    final String attname = (attribute==null?null:attribute.getName());
    if (attname == null) {
        final RuntimeException r =
            new IllegalArgumentException("Attribute name cannot be null");
        throw new RuntimeOperationsException(r,
            "Exception occurred trying to invoke the setter on the MBean");
    }

    // This is a hack: we call getAttribute in order to generate an
    // AttributeNotFoundException if the attribute does not exist.
    //
    Object val = getAttribute(attname);

    // If we reach this point, we know that the requested attribute
    // exists. However, since all attributes are read-only, we throw
    // an AttributeNotFoundException.
    //
    throw new AttributeNotFoundException(attname + " not accessible");
}