org.snmp4j.agent.mo.MOTable Maven / Gradle / Ivy
/*_############################################################################
_##
_## SNMP4J-Agent - MOTable.java
_##
_## Copyright (C) 2005-2009 Frank Fock (SNMP4J.org)
_##
_## Licensed under the Apache License, Version 2.0 (the "License");
_## you may not use this file except in compliance with the License.
_## You may obtain a copy of the License at
_##
_## http://www.apache.org/licenses/LICENSE-2.0
_##
_## Unless required by applicable law or agreed to in writing, software
_## distributed under the License is distributed on an "AS IS" BASIS,
_## WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
_## See the License for the specific language governing permissions and
_## limitations under the License.
_##
_##########################################################################*/
package org.snmp4j.agent.mo;
import org.snmp4j.smi.OID;
import org.snmp4j.agent.MOScope;
import org.snmp4j.smi.Variable;
import org.snmp4j.agent.ManagedObject;
import org.snmp4j.agent.ManagedObjectValueAccess;
/**
* The MOTable interface describes SNMP conceptual tables.
* In general, a conceptual table can be implemented in two different ways:
*
* - For large tables, a virtual table model is best suited where rows are
* created on behalf of a request only. The instrumentation directly propagates
* data to the managed objects without holding the data in a table model.
* - For small or medium size tables, holding the data in (non virtual) table
* model provides data caching and decoupling of the instrumentation.
*
* @author Frank Fock
* @version 1.4
*/
public interface MOTable extends ManagedObject, ManagedObjectValueAccess {
/**
* Finds the object identifier of the first object instance in the specified
* range.
* @param range
* a MOScope specifying the search range.
* @return
* the OID of the lexicographic first instance in the search range or
* null if no such instance exists.
*/
OID find(MOScope range);
/**
* Returns the zero based column index for the specified column
* sub-identifier.
* @param id
* a column sub-identifier (normally one based) as defined in the MIB
* specification.
* @return
* a value greater or equal to zero denoting the column index
* of the column associated with id. The column index
* points into the column array returned by {@link #getColumns}.
* A value less than zero indicates that such a column does not exists
* currently but could be inserted at the (-n)-1 position
* if n is the returned value.
*/
int getColumnIndex(int id);
/**
* Gets the column definitions for this table.
* @return
* an array with the column definitions of this table.
*/
MOColumn[] getColumns();
/**
* Gets the column definition for the specified column.
* @param index
* the (zero-based) column index.
* @return
* a MOColumn instance describing the attributes of requested
* column.
*/
MOColumn getColumn(int index);
/**
* Returns a MOTableCellInfo instance for the supplied
* cell OID. The returned object contains the index, column index, and
* column ID of the specified cell, if available.
* @param oid
* cell instance OID.
* @return
* a MOTableCellInfo instance with the index, column index
* and column ID of the specified cell if available.
*/
MOTableCellInfo getCellInfo(OID oid);
/**
* Returns the number of columns in this table.
* @return
* the column count.
*/
int getColumnCount();
/**
* Gets the index definition of this table.
*
* @return
* a MOTableIndex instance containing the sub-index definitions for this
* table.
*/
MOTableIndex getIndexDef();
/**
* Returns the index part of a column instance identifier of this table.
* @param instanceIdentifier
* the OID of a column instance. The returned result is undefined, when
* this OID is not a column instance OID.
* @return
* an OID representing the index OID of the row identified by the
* instanceIdentifier column instance OID.
*/
OID getIndexPart(OID instanceIdentifier);
/**
* Gets the table model of this table.
* @return
* a MOTableModel instance.
*/
MOTableModel getModel();
/**
* Returns the OID of the table entry.
* @return
* a table entry OID (including the .1 suffix).
*/
OID getOID();
/**
* Returns an array of variables where each variable corresponds to the
* column with the same index. If a column has a default value, the returned
* variable is not null and contains that default value.
*
* @return
* the default variables for a newly created row as an array of
* Variable instances.
*/
Variable[] getDefaultValues();
/**
* Gets the value of the cell instance with the specified instance OID.
* @param cellOID
* the instance OID of the requested cell.
* @return
* the value of the cell or null if such a cell does not
* exist.
*/
Variable getValue(OID cellOID);
/**
* Gets the value of the cell instance in the specified column and row.
* @param index
* the row index of the cell.
* @param col
* the column index of the cell.
* @return
* the value of the cell or null if such a cell does not
* exist.
*/
Variable getValue(OID index, int col);
/**
* Adds a MOChangeListener that needs to be informed about
* state changes of this table.
* @param l
* a MOChangeListener instance.
*/
void addMOChangeListener(MOChangeListener l);
/**
* Removes a MOChangeListener
* @param l
* a MOChangeListener instance.
*/
void removeMOChangeListener(MOChangeListener l);
/**
* Adds a MOTableRowListener listener that needs to be informed
* about row changes (creation, addition, removal).
* @param l
* a MOTableRowListener instance.
*/
void addMOTableRowListener(MOTableRowListener l);
/**
* Removes MOTableRowListener instance.
* @param l
* a MOTableRowListener instance.
*/
void removeMOTableRowListener(MOTableRowListener l);
/**
* Creates a new row for this table with the supplied index and initial
* values. If one of the {@link MOTableRowListener} deny the row creation
* attempt then null will be returned.
* @param index
* the index OID of the new row.
* @param initialValues
* the initial values that should be assigned to the new row.
* @return
* the created MOTableRow instance or null if
* the row cannot be created.
*/
MOTableRow createRow(OID index, Variable[] initialValues);
/**
* Creates a new row for this table with the supplied index and
* default values. If one of the {@link MOTableRowListener}
* deny the row creation attempt then null will be returned.
* @param index
* the index OID of the new row.
* @return
* the created MOTableRow instance or null if
* the row cannot be created.
*/
MOTableRow createRow(OID index);
/**
* Adds the supplied row to the underlying table model and fires the
* appropriate {@link MOTableRowEvent}. Since this method is typically
* called during the commit phase of a SET request that creates a table,
* it should be avoided to return an error here. Instead error checking
* should be placed in the
* @param row
* the MOTableRow to add.
* @return
* true if the row has been added or false
* if it could not be added.
*/
boolean addRow(MOTableRow row);
/**
* Removes the row with the specified index and returns it if the operation
* was successful.
* @param index
* the index OID of the row to remove.
* @return
* the removed row or null if the row cannot be found or
* cannot be removed.
*/
MOTableRow removeRow(OID index);
}