org.jrobin.core
Class Header

java.lang.Object
  extended by org.jrobin.core.Header

public class Header
extends java.lang.Object

Class to represent RRD header. Header information is mainly static (once set, it cannot be changed), with the exception of last update time (this value is changed whenever RRD gets updated).

Normally, you don't need to manipulate the Header object directly - JRobin framework does it for you.


Method Summary
 void copyStateTo(org.jrobin.core.RrdUpdater other)
          Copies object's internal state to another Header object.
 int getArcCount()
          Returns the number of archives defined in the RRD.
 int getDsCount()
          Returns the number of datasources defined in the RRD.
 long getLastUpdateTime()
          Returns the last update time of the RRD.
 org.jrobin.core.RrdAllocator getRrdAllocator()
          Required to implement RrdUpdater interface.
 RrdBackend getRrdBackend()
          Returns the underlying storage (backend) object which actually performs all I/O operations.
 java.lang.String getSignature()
          Returns RRD signature.
 long getStep()
          Returns primary RRD time step.
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Method Detail

getSignature

public java.lang.String getSignature()
                              throws java.io.IOException
Returns RRD signature. The returned string will be always of the form JRobin, version x.x. Note: RRD format did not change since Jrobin 1.0.0 release (and probably never will).

Returns:
RRD signature
Throws:
java.io.IOException - Thrown in case of I/O error

getLastUpdateTime

public long getLastUpdateTime()
                       throws java.io.IOException
Returns the last update time of the RRD.

Returns:
Timestamp (Unix epoch, no milliseconds) corresponding to the last update time.
Throws:
java.io.IOException - Thrown in case of I/O error

getStep

public long getStep()
             throws java.io.IOException
Returns primary RRD time step.

Returns:
Primary time step in seconds
Throws:
java.io.IOException - Thrown in case of I/O error

getDsCount

public int getDsCount()
               throws java.io.IOException
Returns the number of datasources defined in the RRD.

Returns:
Number of datasources defined
Throws:
java.io.IOException - Thrown in case of I/O error

getArcCount

public int getArcCount()
                throws java.io.IOException
Returns the number of archives defined in the RRD.

Returns:
Number of archives defined
Throws:
java.io.IOException - Thrown in case of I/O error

copyStateTo

public void copyStateTo(org.jrobin.core.RrdUpdater other)
                 throws java.io.IOException,
                        RrdException
Copies object's internal state to another Header object.

Parameters:
other - New Header object to copy state to
Throws:
java.io.IOException - Thrown in case of I/O error
RrdException - Thrown if supplied argument is not a Header object

getRrdBackend

public RrdBackend getRrdBackend()
Returns the underlying storage (backend) object which actually performs all I/O operations.

Returns:
I/O backend object

getRrdAllocator

public org.jrobin.core.RrdAllocator getRrdAllocator()
Required to implement RrdUpdater interface. You should never call this method directly.

Returns:
Allocator object