org.jrobin.graph

Class RrdGraphDefTemplate

public class RrdGraphDefTemplate extends XmlTemplate implements RrdGraphConstants

Class used to create an arbitrary number of RrdGraphDef (graph definition) objects from a single XML template. XML template can be supplied as an XML InputSource, XML file or XML formatted string.

Here is an example of a properly formatted XML template with all available options in it (unwanted options can be removed/ignored):

 <rrd_graph_def>
     <!-- use '-' to represent in-memory graph -->
     <filename>test.png</filename>
     <!--
         starting and ending timestamps can be specified by
         using at-style time specification, or by specifying
         exact timestamps since epoch (without milliseconds)
     -->
     <span>
         <start>now - 1d</start>
         <end>now</end>
     </span>
     <options>
         <!--
             specify 'true' if you want to use RrdDbPool while
             creating graph
         -->
         <use_pool>false</use_pool>
         <anti_aliasing>true</anti_aliasing>
         <time_grid>
             <show_grid>true</show_grid>
             <!-- allowed units: second, minute, hour, day, week, month, year -->
             <minor_grid_unit>minute</minor_grid_unit>
             <minor_grid_unit_count>60</minor_grid_unit_count>
             <major_grid_unit>hour</major_grid_unit>
             <major_grid_unit_count>2</major_grid_unit_count>
             <label_unit>hour</label_unit>
             <label_unit_count>2</label_unit_count>
             <label_span>1200</label_span>
             <!-- use SimpleDateFormat or strftime-like format to format labels -->
             <label_format>dd-MMM-yy</label_format>
         </time_grid>
         <value_grid>
             <show_grid>true</show_grid>
             <grid_step>100.0</grid_step>
             <label_factor>5</label_factor>
         </value_grid>
         <no_minor_grid>true</no_minor_grid>
         <alt_y_grid>true</alt_y_grid>
         <alt_y_mrtg>true</alt_y_mrtg>
         <alt_autoscale>true</alt_autoscale>
         <alt_autoscale_max>true</alt_autoscale_max>
         <units_exponent>3</units_exponent>
         <units_length>13</units_length>
         <vertical_label>Speed (kbits/sec)</vertical_label>
         <width>444</width>
         <height>222</height>
         <interlaced>true</interlaced>
         <image_info>filename = %s, width=%d, height=%d</image_info>
         <image_format>png</image_format>
         <image_quality>0.8</image_quality>
         <background_image>luka.png</background_image>
         <overlay_image>luka.png</overlay_image>
         <unit>kilos</unit>
         <lazy>false</lazy>
         <min_value>0</min_value>
         <max_value>5000</max_value>
         <rigid>true</rigid>
         <base>1000</base>
         <logarithmic>false</logarithmic>
         <colors>
             <canvas>#FFFFFF</canvas>
             <back>#FFFFFF</back>
             <shadea>#AABBCC</shadea>
             <shadeb>#DDDDDD</shadeb>
             <grid>#FF0000</grid>
             <mgrid>#00FF00</mgrid>
             <font>#FFFFFF</font>
             <frame>#EE00FF</frame>
             <arrow>#FF0000</arrow>
         </colors>
         <no_legend>false</no_legend>
         <only_graph>false</only_graph>
         <force_rules_legend>false</force_rules_legend>
         <title>This is a title</title>
         <step>300</step>
         <fonts>
             <small_font>
                 <name>Courier</name>
                 <style>bold italic</style>
                 <size>12</size>
             </small_font>
             <large_font>
                 <name>Courier</name>
                 <style>plain</style>
                 <size>11</size>
             </large_font>
         </fonts>
         <first_day_of_week>SUNDAY</first_day_of_week>
     </options>
     <datasources>
         <def>
             <name>x</name>
             <rrd>test.rrd</rrd>
             <source>sun</source>
             <cf>AVERAGE</cf>
             <backend>FILE</backend>
         </def>
         <def>
             <name>y</name>
             <rrd>test.rrd</rrd>
             <source>shade</source>
             <cf>AVERAGE</cf>
         </def>
         <cdef>
             <name>x_plus_y</name>
             <rpn>x,y,+</rpn>
         </cdef>
         <cdef>
             <name>x_minus_y</name>
             <rpn>x,y,-</rpn>
         </cdef>
         <sdef>
             <name>x_avg</name>
             <source>x</source>
             <cf>AVERAGE</cf>
         </sdef>
         <sdef>
             <name>y_max</name>
             <source>y</source>
             <cf>MAX</cf>
         </sdef>
     </datasources>
     <graph>
         <area>
             <datasource>x</datasource>
             <color>#FF0000</color>
             <legend>X value\r</legend>
         </area>
         <stack>
             <datasource>y</datasource>
             <color>#00FF00</color>
             <legend>Y value\r</legend>
         </stack>
         <line>
             <datasource>x</datasource>
             <color>#FF0000</color>
             <legend>X value\r</legend>
             <width>2</width>
         </line>
         <print>
             <datasource>x</datasource>
             <cf>AVERAGE</cf>
             <format>Average is %7.3f\c</format>
         </print>
         <gprint>
             <datasource>y</datasource>
             <cf>MAX</cf>
             <format>Max is %7.3f\c</format>
         </gprint>
         <hrule>
             <value>1250</value>
             <color>#0000FF</color>
             <legend>This is a horizontal rule</legend>
         </hrule>
         <vrule>
             <time>now-6h</time>
             <color>#0000FF</color>
             <legend>This is a vertical rule</legend>
         </vrule>
         <comment>Simple comment</comment>
         <comment>One more comment\c</comment>
     </graph>
 </rrd_graph_def>
 
Notes on the template syntax:

Any template value (text between <some_tag> and </some_tag>) can be replaced with a variable of the following form: ${variable_name}. Use setVariable() methods from the base class to replace template variables with real values at runtime.

Typical usage scenario:

You should create new RrdGraphDefTemplate object only once for each XML template. Single template object can be reused to create as many RrdGraphDef objects as needed, with different values specified for template variables. XML synatax check is performed only once - the first graph definition object gets created relatively slowly, but it will be created much faster next time.
Constructor Summary
RrdGraphDefTemplate(InputSource inputSource)
Creates template object from any parsable XML source
RrdGraphDefTemplate(File xmlFile)
Creates template object from the file containing XML template code
RrdGraphDefTemplate(String xmlString)
Creates template object from the string containing XML template code
Method Summary
RrdGraphDefgetRrdGraphDef()
Creates RrdGraphDef object which can be used to create RrdGraph object (actual JRobin graphs).

Constructor Detail

RrdGraphDefTemplate

public RrdGraphDefTemplate(InputSource inputSource)
Creates template object from any parsable XML source

Parameters: inputSource XML source

Throws: IOException thrown in case of I/O error RrdException usually thrown in case of XML related error

RrdGraphDefTemplate

public RrdGraphDefTemplate(File xmlFile)
Creates template object from the file containing XML template code

Parameters: xmlFile file containing XML template

Throws: IOException thrown in case of I/O error RrdException usually thrown in case of XML related error

RrdGraphDefTemplate

public RrdGraphDefTemplate(String xmlString)
Creates template object from the string containing XML template code

Parameters: xmlString string containing XML template

Throws: IOException thrown in case of I/O error RrdException usually thrown in case of XML related error

Method Detail

getRrdGraphDef

public RrdGraphDef getRrdGraphDef()
Creates RrdGraphDef object which can be used to create RrdGraph object (actual JRobin graphs). Before this method is called, all template variables (if any) must be resolved (replaced with real values). See setVariable() method information to understand how to supply values for template variables.

Returns: Graph definition which can be used to create RrdGraph object (actual JRobin graphs)

Throws: RrdException Thrown if parsed XML template contains invalid (unrecognized) tags