Java Agent
JaCoCo uses class file instrumentation to record execution coverage data. Class files are instrumented on-the-fly using a so called Java agent. This mechanism allows in-memory pre-processing of all class files during class loading independent of the application framework. The JaCoCo agent collects execution information and dumps it to a local file when the JVM exits.
If you use the JaCoCo Ant tasks you don't have to care about the agent and its options directly. This is transparently handled by the Ant tasks.
The agent jacocoagent.jar
is part of the JaCoCo distribution and
includes all required dependencies. A Java agent can be activated with the
following JVM option:
-javaagent:[yourpath/]jacocoagent.jar=[option1]=[value1],[option2]=[value2]
The JaCoCo agent accepts the following options:
Option | Description | Default |
destfile |
Path to the output file for execution data. | jacoco.exec |
append |
If set to true and the execution data file already
exists, coverage data is appended to the existing file. If set to
false , an existing execution data file will be replaced.
|
true |
includes |
A list of class names that should be included in execution analysis.
The list entries are separated by a vertical bar (| ) and
may use wildcard characters (* and ? ).
Except for performance optimization or technical corner cases this
option is normally not required.
|
* (all classes) |
excludes |
A list of class names that should be excluded from execution analysis.
The list entries are separated by a vertical bar (| ) and
may use wildcard characters (* and ? ).
Except for performance optimization or technical corner cases this
option is normally not required.
|
empty (no excluded classes) |
exclclassloader |
A list of class loader names that should be excluded from execution
analysis. The list entries are separated by a vertical bar
(| ) and may use wildcard characters (* and
? ). This option might be required in case of special
frameworks that conflict with JaCoCo code instrumentation, in
particular class loaders that do not have access to the Java runtime
classes.
|
sun.reflect.DelegatingClassLoader |