Context

John Doe remarked in #AP1432 that there may be too much code in our application that isn't used at all. Before migrating the application to the new platform, we have to analyze which parts of the system are still in use and which are not.

Idea

To understand how much code isn't used, we recorded the executed code in production with the coverage tool JaCoCo. The measurement took place between 21st Oct 2017 and 27st Oct 2017. The results were exported into a CSV file using the JaCoCo command line tool with the following command:

java -jar jacococli.jar report "C:\Temp\jacoco.exec" --classfiles \
C:\dev\repos\buschmais-spring-petclinic\target\classes --csv jacoco.csv

The CSV file contains all lines of code that were passed through during the measurement's time span.



In [1]:

    
%%classpath add mvn
tech.tablesaw tablesaw-beakerx 0.24.5
tech.tablesaw tablesaw-jsplot 0.24.5



In [2]:

    
%import tech.tablesaw.api.*
%import tech.tablesaw.columns.*
%import static tech.tablesaw.aggregate.AggregateFunctions.*

tech.tablesaw.beakerx.TablesawDisplayer.register()

OutputCell.HIDDEN



In [3]:

    
coverage = Table.read().csv("datasets/jacoco_production_coverage_spring_petclinic.csv")
coverage.first(5)

We just take the only relevant data LINES_COVERED as well as the information about the packages in PACKAGE as well as the CLASS columns.



In [4]:

    
coverage = coverage.retainColumns("PACKAGE", "CLASS", "LINE_COVERED")
coverage.first(5)

Analysis

It was stated that whole packages wouldn't be needed anymore and that they could be safely removed. Therefore, we sum up the coverage data per class for each package and calculate the coverage ratio for each package.



In [5]:

    
per_package = coverage.summarize("LINE_COVERED", sum).by("PACKAGE");
per_package

Visualisation

We plot the data for the coverage ratio to get a brief overview of the result.



In [6]:

    
def bars = new CategoryBars(
    value: per_package.column('Sum [LINE_COVERED]').asList())
new CategoryPlot(
    categoryNames: per_package.column('PACKAGE').asList(),
    orientation: PlotOrientationType.HORIZONTAL) << bars

Conclusion

The JDBC package org.springframework.samples.petclinic.repository.jdbc isn't used at all and can be left out safely when migrating to the new platform.