org.snmp4j.agent.mo

Class MOColumn<V extends org.snmp4j.smi.Variable>

java.lang.Object

org.snmp4j.agent.mo.MOColumn<V>

All Implemented Interfaces:

Comparable

Direct Known Subclasses:

MOMutableColumn, TimeStamp

public class MOColumn<V extends org.snmp4j.smi.Variable>
extends Object
implements Comparable

The MOColumn class represents columnar SMI objects. It represents all instances of a table's column not only a single instance (cell). Objects represented by MOColumn cannot be modified via SNMP, thus MOColumn supports read-only maximum access only.

Version:

2.6

Author:

Frank Fock

See Also:

MOMutableColumn

Constructor Summary

Constructors

Constructor and Description
MOColumn(int columnID, int syntax) Creates a read-only column object with the given column and syntax.
MOColumn(int columnID, int syntax, MOAccess access) Creates a column object with the given column, syntax, and maximum access.

Method Summary

Modifier and Type	Method and Description
int	compareTo(Object column) Compares this managed object column by its ID with another column.
void	get(SubRequest subRequest, MOTableRow row, int column) Process a get sub-request for the specified table row and column.
MOAccess	getAccess()
int	getColumnID()
org.snmp4j.smi.Variable	getRestoreValue(org.snmp4j.smi.Variable[] rowValues, int column) Return the restore value for this column and the given row.
org.snmp4j.smi.Variable	getStoreValue(MOTableRow row, int column) Return the content of this column's value of the given row for persistent storage.
int	getSyntax()
MOTable	getTable()
V	getValue(MOTableRow row, int column, SubRequest subRequest) Gets the value of the specified column from the provided row.
boolean	isVolatile(MOTableRow<V> row, int column) Tests if the supplied row is volatile or persistent.
void	setAccess(MOAccess access)
void	setColumnID(int columnID)
void	setSyntax(int syntax)
<R extends MOTableRow> void	setTable(MOTable<R,? extends MOColumn,? extends MOTableModel<R>> table) Sets the table instance this columnar object is contained in.
String	toString()

Methods inherited from class java.lang.Object

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

Constructor Detail

MOColumn

public MOColumn(int columnID,
                int syntax)

Creates a read-only column object with the given column and syntax.

Parameters:

columnID - the column ID which is ID the last sub-identifier of the corresponding OBJECT-TYPE definition.

syntax - the syntax of the objects in this column. See SMIConstants for possible values.

MOColumn

public MOColumn(int columnID,
                int syntax,
                MOAccess access)

Creates a column object with the given column, syntax, and maximum access. Since MOColumn only supports read-only columns the only reasonable values for access are 'not-accessible' and 'read-only'. Generally this constructor should not be called directly.

Parameters:

columnID - the column ID which is ID the last sub-identifier of the corresponding OBJECT-TYPE definition.

syntax - the syntax of the objects in this column. See SMIConstants for possible values.

access - the maximum access of the column.

Method Detail

setColumnID

public void setColumnID(int columnID)

setSyntax

public void setSyntax(int syntax)

setAccess

public void setAccess(MOAccess access)

setTable

public <R extends MOTableRow> void setTable(MOTable<R,? extends MOColumn,? extends MOTableModel<R>> table)

Sets the table instance this columnar object is contained in. This method should be called by MOTable instance to register the table with the column.

Type Parameters:

R - the MOTableRow type supported by the table.

Parameters:

table - the MOTable instance where this column is contained in.

getColumnID

public int getColumnID()

getSyntax

public int getSyntax()

getAccess

public MOAccess getAccess()

getTable

public MOTable getTable()

getValue

public V getValue(MOTableRow row,
                  int column,
                  SubRequest subRequest)

Gets the value of the specified column from the provided row. The optional subRequest parameter provides information on the currently processed SNMP request if the value retrieval is trigger by a SNMP command.

Parameters:

row - the row with the value to be returned.

column - the column index pointing to the column to return in the above row.

subRequest - an optional sub-request on which behalf this value retrieval is executed.

Returns:

the value as a pointer to the cell value or null if such a value does not exist.

Since:

2.6

isVolatile

public boolean isVolatile(MOTableRow<V> row,
                          int column)

Tests if the supplied row is volatile or persistent. If volatile then the row will not be saved when the table is saved to persistent storage.

Parameters:

row - a row of the table where this column is part of.

column - the column index of this column in row.

Returns:

true if row should not be

getRestoreValue

public org.snmp4j.smi.Variable getRestoreValue(org.snmp4j.smi.Variable[] rowValues,
                                               int column)

Return the restore value for this column and the given row.

Parameters:

rowValues - a row of the table where this column is part of.

column - the column index of this column in row.

Returns:

the restored value. By default this is rowValues[column].

Since:

2.4

getStoreValue

public org.snmp4j.smi.Variable getStoreValue(MOTableRow row,
                                             int column)

Return the content of this column's value of the given row for persistent storage.

Parameters:

row - a row of the table where this column is part of.

column - the column index of this column in row.

Returns:

the value to be stored persistently for this row and column.

Since:

2.4

compareTo

public int compareTo(Object column)

Compares this managed object column by its ID with another column.

Specified by:

compareTo in interface Comparable

Parameters:

column - another MOColumn.

Returns:

int a negative integer, zero, or a positive integer as this column ID is less than, equal to, or greater than the specified object's column ID.

toString

public String toString()

Overrides:

toString in class Object

get

public void get(SubRequest subRequest,
                MOTableRow row,
                int column)

Process a get sub-request for the specified table row and column.

Parameters:

subRequest - the GET sub-request to execute.

row - the row that contains the value to return in the GET response PDU.

column - the column index of the value to return in subRequest