java.lang.Object

org.rrd4j.core.Header

All Implemented Interfaces:: RrdUpdater<Header>

public class Header
extends Object
implements RrdUpdater<Header>

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 - Rrd4j framework does it for you.

Author:: Sasa Markovic*

Field Summary

Fields
Modifier and Type	Field	Description
`(package private) static String`	`DEFAULT_SIGNATURE`
`(package private) static String`	`RRDTOOL_VERSION1`
`(package private) static String`	`RRDTOOL_VERSION3`
`(package private) static String`	`SIGNATURE`
`(package private) static int`	`SIGNATURE_LENGTH`

Constructor Summary

Constructors

Constructor Description

Header(RrdDb parentDb, DataImporter reader)

Header(RrdDb parentDb, RrdDef rrdDef)

Method Summary

Modifier and Type	Method	Description
`(package private) void`	`appendXml(XmlWriter writer)`
`void`	`copyStateTo(Header header)`	copyStateTo.
`(package private) String`	`dump()`
`int`	`getArcCount()`	Returns the number of archives defined in the RRD.
`int`	`getDsCount()`	Returns the number of datasources defined in the RRD.
`String`	`getInfo()`	getInfo.
`long`	`getLastUpdateTime()`	Returns the last update time of the RRD.
`RrdAllocator`	`getRrdAllocator()`	Required to implement RrdUpdater interface.
`RrdBackend`	`getRrdBackend()`	Returns the underlying storage (backend) object which actually performs all I/O operations.
`String`	`getSignature()`	Returns RRD signature.
`long`	`getStep()`	Returns primary RRD time step.
`int`	`getVersion()`	Return the RRD version.
`(package private) boolean`	`isRrd4jHeader()`
`void`	`setInfo(String info)`	setInfo.
`(package private) void`	`setLastUpdateTime(long lastUpdateTime)`
`(package private) void`	`validateHeader()`

Methods inherited from class java.lang.Object

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

Field Details
- SIGNATURE_LENGTH
  
  static final int SIGNATURE_LENGTH
  
  See Also:
  
  Constant Field Values
- SIGNATURE
  
  static final String SIGNATURE
  
  See Also:
  
  Constant Field Values
- DEFAULT_SIGNATURE
  
  static final String DEFAULT_SIGNATURE
  
  See Also:
  
  Constant Field Values
- RRDTOOL_VERSION1
  
  static final String RRDTOOL_VERSION1
  
  See Also:
  
  Constant Field Values
- RRDTOOL_VERSION3
  
  static final String RRDTOOL_VERSION3
  
  See Also:
  
  Constant Field Values
Constructor Details
- Header
  
  Header(RrdDb parentDb, RrdDef rrdDef) throws IOException
  
  Throws:
  
  IOException
- Header
  
  Header(RrdDb parentDb, DataImporter reader) throws IOException
  
  Throws:
  
  IOException
Method Details
- getSignature
  
  public String getSignature() throws IOException
  
  Returns RRD signature. Initially, the returned string will be of the form Rrd4j, version x.x.
  
  Returns:
  
  RRD signature
  
  Throws:
  
  IOException - Thrown in case of I/O error
- getInfo
  
  public String getInfo() throws IOException
  
  getInfo.
  
  Returns:
  
  a String object.
  
  Throws:
  
  IOException - if any.
- setInfo
  
  public void setInfo(String info) throws IOException
  
  setInfo.
  
  Parameters:
  
  info - a String object.
  
  Throws:
  
  IOException - if any.
- getLastUpdateTime
  
  public long getLastUpdateTime() throws IOException
  
  Returns the last update time of the RRD.
  
  Returns:
  
  Timestamp (Unix epoch, no milliseconds) corresponding to the last update time.
  
  Throws:
  
  IOException - Thrown in case of I/O error
- getStep
  
  public long getStep() throws IOException
  
  Returns primary RRD time step.
  
  Returns:
  
  Primary time step in seconds
  
  Throws:
  
  IOException - Thrown in case of I/O error
- getDsCount
  
  public int getDsCount() throws IOException
  
  Returns the number of datasources defined in the RRD.
  
  Returns:
  
  Number of datasources defined
  
  Throws:
  
  IOException - Thrown in case of I/O error
- getArcCount
  
  public int getArcCount() throws IOException
  
  Returns the number of archives defined in the RRD.
  
  Returns:
  
  Number of archives defined
  
  Throws:
  
  IOException - Thrown in case of I/O error
- setLastUpdateTime
  
  void setLastUpdateTime(long lastUpdateTime) throws IOException
  
  Throws:
  
  IOException
- dump
  
  String dump() throws IOException
  
  Throws:
  
  IOException
- appendXml
  
  void appendXml(XmlWriter writer) throws IOException
  
  Throws:
  
  IOException
- copyStateTo
  
  public void copyStateTo(Header header) throws IOException
  
  copyStateTo.
  Copies object's internal state to another Header object.
  
  Specified by:
  
  copyStateTo in interface RrdUpdater<Header>
  
  Parameters:
  
  header - a RrdUpdater object.
  
  Throws:
  
  IOException - if any.
- getRrdBackend
  
  public RrdBackend getRrdBackend()
  
  Returns the underlying storage (backend) object which actually performs all I/O operations.
  
  Specified by:
  
  getRrdBackend in interface RrdUpdater<Header>
  
  Returns:
  
  I/O backend object
- getVersion
  
  public int getVersion() throws IOException
  
  Return the RRD version.
  
  Returns:
  
  RRD version
  
  Throws:
  
  IOException - if any.
- isRrd4jHeader
  
  boolean isRrd4jHeader()
- validateHeader
  
  void validateHeader() throws IOException
  
  Throws:
  
  IOException
- getRrdAllocator
  
  public RrdAllocator getRrdAllocator()
  
  Required to implement RrdUpdater interface. You should never call this method directly.
  
  Specified by:
  
  getRrdAllocator in interface RrdUpdater<Header>
  
  Returns:
  
  Allocator object

Constructor	Description
`Header(RrdDb parentDb, DataImporter reader)`
`Header(RrdDb parentDb, RrdDef rrdDef)`

Class Header

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Details

Constructor Details

Method Details