GraphListener (Javadocs [I2P+ 2.13.0+]

java.lang.Object
- net.i2p.router.web.GraphListener

All Implemented Interfaces:
RateSummaryListener
```
public class GraphListener
extends Object
implements RateSummaryListener
```
Creates and updates the in-memory or on-disk RRD database, and provides methods to generate graphs of the data

Field Summary

Fields
Modifier and Type	Field and Description
`(package private) static ConsolFun`	`CF` Consolidation function used for RRD archives.
`(package private) static DsType`	`DS` Data source type used for RRD datasources.
`(package private) static int`	`GRAPH_END_OFFSET_SECONDS` Offset (seconds) subtracted from "now" when computing the fetch window end, so a clock skewed slightly ahead of system time does not yield NaNs.
`static int`	`MAX_ROWS`
`(package private) static int`	`PERIODS` Number of periods in one day (1440 = 60 minutes * 24 hours at 1-minute resolution).
`static String`	`PROP_PERSISTENT`
`(package private) static String`	`RRD_DIR` note that .jrb files are NOT compatible with .rrd files
`(package private) static String`	`RRD_PREFIX` R r d p r e f i x
`(package private) static String`	`RRD_SUFFIX` R r d s u f f i x

Constructor Summary
Constructors
Constructor and Description
GraphListener(Rate r)
Create a listener for the given rate stat.

Constructors
Constructor and Description
`GraphListener(Rate r)` Create a listener for the given rate stat.

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`void`	`add(double totalValue, long eventCount, double totalEventTime, long period)` Add a new data point to the RRD database.
`(package private) static String`	`createName(I2PAppContext ctx, String wanted)` JRobin can only deal with 20 character data source names, so we need to create a unique, munged version from the user/developer-visible name.
`boolean`	`equals(Object obj)` Compare with another listener by the underlying rate.
`(package private) RrdBackendFactory`	`getBackendFactory()`
`(package private) RrdDb`	`getData()` Get the RRD database instance.
`(package private) String`	`getEventName()` Get the RRD datasource name for the event count.
`double[]`	`getLastValues(int count)` Fetch the last `count` data points from the RRD database for use by the dual-baseline minigraph renderer (data-rx/data-tx attributes on the canvas).
`(package private) String`	`getName()` Get the RRD datasource name for the primary stat.
`Rate`	`getRate()` Retrieve the tracked rate.
`(package private) int`	`getRows()` Get the number of rows in the RRD archive.
`int`	`hashCode()` Hash code based on the underlying rate.
`(package private) long`	`now()` Get the current time from the router clock.
`void`	`renderGraph(OutputStream out)` Render a graph of the stat data using default settings.
`void`	`renderGraph(OutputStream out, int width, int height, boolean hideLegend, boolean hideGrid, boolean hideTitle, boolean showEvents, int periodCount, int end, boolean showCredit)` Single graph.
`void`	`renderGraph(OutputStream out, int width, int height, boolean hideLegend, boolean hideGrid, boolean hideTitle, boolean showEvents, int periodCount, int end, boolean showCredit, GraphListener lsnr2, String titleOverride, boolean showRestarts)` Single or two-data-source graph.
`boolean`	`startListening()`
`void`	`stopListening()` Stop listening and close the RRD database.

Methods inherited from class java.lang.Object
clone, finalize, getClass, notify, notifyAll, toString, wait, wait, wait

- Field Detail
  - CF
```
static final ConsolFun CF
```
    Consolidation function used for RRD archives.
  - DS
```
static final DsType DS
```
    Data source type used for RRD datasources.
  - GRAPH_END_OFFSET_SECONDS
```
static final int GRAPH_END_OFFSET_SECONDS
```
    Offset (seconds) subtracted from "now" when computing the fetch window end, so a clock skewed slightly ahead of system time does not yield NaNs. Shared with GraphRenderer, which applies the same window for plotting.
    See Also:
    Constant Field Values
  - MAX_ROWS
```
public static final int MAX_ROWS
```
    See Also:
    Constant Field Values
  - PERIODS
```
static final int PERIODS
```
    Number of periods in one day (1440 = 60 minutes * 24 hours at 1-minute resolution).
    See Also:
    Constant Field Values
  - PROP_PERSISTENT
```
public static final String PROP_PERSISTENT
```
    See Also:
    Constant Field Values
  - RRD_DIR
```
static final String RRD_DIR
```
    note that .jrb files are NOT compatible with .rrd files
    See Also:
    Constant Field Values
  - RRD_PREFIX
```
static final String RRD_PREFIX
```
    R r d p r e f i x
    See Also:
    Constant Field Values
  - RRD_SUFFIX
```
static final String RRD_SUFFIX
```
    R r d s u f f i x
    See Also:
    Constant Field Values
- Constructor Detail
  - GraphListener
```
public GraphListener(Rate r)
```
    Create a listener for the given rate stat.
    Parameters:
    r - the rate to track
- Method Detail
  - add
```
public void add(double totalValue,
                long eventCount,
                double totalEventTime,
                long period)
```
    Add a new data point to the RRD database.
    Specified by:
    add in interface RateSummaryListener
    Parameters:
    totalValue - the total value for the period
    eventCount - the number of events in the period
    totalEventTime - the total event time for the period
    period - the period duration in milliseconds
  - createName
```
static String createName(I2PAppContext ctx,
                         String wanted)
```
    JRobin can only deal with 20 character data source names, so we need to create a unique, munged version from the user/developer-visible name.
  - equals
```
public boolean equals(Object obj)
```
    Compare with another listener by the underlying rate.
    Overrides:
    equals in class Object
    Parameters:
    obj - the object to compare with
    Returns:
    true if the listeners track the same rate
  - getBackendFactory
```
RrdBackendFactory getBackendFactory()
```
  - getData
```
RrdDb getData()
```
    Get the RRD database instance.
    Returns:
    the RRD database
  - getEventName
```
String getEventName()
```
    Get the RRD datasource name for the event count.
    Returns:
    the event datasource name
  - getLastValues
```
public double[] getLastValues(int count)
```
    Fetch the last count data points from the RRD database for use by the dual-baseline minigraph renderer (data-rx/data-tx attributes on the canvas). Points are right-aligned; the returned array is NaN-padded on the left when fewer points are available.
    Specified by:
    getLastValues in interface RateSummaryListener
    Parameters:
    count - number of most recent data points to retrieve
    Returns:
    array of average values (units depend on the stat), length = count
  - getName
```
String getName()
```
    Get the RRD datasource name for the primary stat.
    Returns:
    the datasource name
  - getRate
```
public Rate getRate()
```
    Retrieve the tracked rate.
    Returns:
    the rate instance
  - getRows
```
int getRows()
```
    Get the number of rows in the RRD archive.
    Returns:
    the row count
  - hashCode
```
public int hashCode()
```
    Hash code based on the underlying rate.
    Overrides:
    hashCode in class Object
    Returns:
    the hash code
  - now
```
long now()
```
    Get the current time from the router clock.
    Returns:
    the current time in milliseconds
  - renderGraph
```
public void renderGraph(OutputStream out)
                 throws IOException
```
    Render a graph of the stat data using default settings.
    Parameters:
    out - the output stream to write the graph to
    Throws:
    IOException - if rendering fails
  - renderGraph
```
public void renderGraph(OutputStream out,
                        int width,
                        int height,
                        boolean hideLegend,
                        boolean hideGrid,
                        boolean hideTitle,
                        boolean showEvents,
                        int periodCount,
                        int end,
                        boolean showCredit)
                 throws IOException
```
    Single graph.
    Parameters:
    end - number of periods before now
    Throws:
    IOException
  - renderGraph
```
public void renderGraph(OutputStream out,
                        int width,
                        int height,
                        boolean hideLegend,
                        boolean hideGrid,
                        boolean hideTitle,
                        boolean showEvents,
                        int periodCount,
                        int end,
                        boolean showCredit,
                        GraphListener lsnr2,
                        String titleOverride,
                        boolean showRestarts)
                 throws IOException
```
    Single or two-data-source graph.
    Parameters:
    lsnr2 - 2nd data source to plot on same graph, or null. Not recommended for events.
    titleOverride - If non-null, overrides the title
    showRestarts - if true, draw the vertical restart lines and "Router restarted" label
    Throws:
    IOException
  - startListening
```
public boolean startListening()
```
    Returns:
    success
  - stopListening
```
public void stopListening()
```
    Stop listening and close the RRD database.

Class GraphListener

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

CF

DS

GRAPH_END_OFFSET_SECONDS

MAX_ROWS

PERIODS

PROP_PERSISTENT

RRD_DIR

RRD_PREFIX

RRD_SUFFIX

Constructor Detail

GraphListener

Method Detail

add

createName

equals

getBackendFactory

getData

getEventName

getLastValues

getName

getRate

getRows

hashCode

now

renderGraph

renderGraph

renderGraph

startListening

stopListening