3:37 p.m.
Hi guys,
We should actively notify/teach each other about tips and tricks.
There's a lot we can learn from each other.
I'll start with a build tip:
The problem
========
- How bloated is the dependency tree of my module? This affects the
download zip size, but also the minimal jars needed to run.
- Are there dead dependency left in my module?
The solution
========
- First thing to understand is that it has to reviewed module by module
(focus on end-user modules such as drools-compiler, drools-camel-server,
guvnor-webapp, ...).
- Use the command *mvn dependency:tree*
Example
=====
Here's the output on drools-compiler.
I've annotated a couple of possible incidents which might or might not
be a problem.
It's hard to tell without someone with extensive drools-compiler
experience looking further into it.
drools-compiler [master] $ mvn dependency:tree
[INFO] Scanning for projects...
[INFO]
[INFO]
------------------------------------------------------------------------
[INFO] Building Drools :: Compiler 5.3.0-SNAPSHOT
[INFO]
------------------------------------------------------------------------
[INFO]
[INFO] --- maven-dependency-plugin:2.2:tree (default-cli) @
drools-compiler ---
[INFO] org.drools:drools-compiler:jar:5.3.0-SNAPSHOT
[INFO] +- org.drools:drools-core:jar:5.3.0-SNAPSHOT:compile
[INFO] | \- org.drools:knowledge-api:jar:5.3.0-SNAPSHOT:compile
[INFO] +- org.drools:drools-core:test-jar:tests:5.3.0-SNAPSHOT:test
[INFO] +- org.apache.felix:org.osgi.core:jar:1.4.0:provided
[INFO] +- org.apache.felix:org.osgi.compendium:jar:1.4.0:provided
[INFO] +- org.antlr:*antlr-runtime:jar:3.3*:compile
[INFO] +- org.antlr:*antlr:jar:3.3*:compile
*Incident* 1: maybe org.antlr:antlr-runtime:jar:3.3 is a subset of
org.antlr:antlr-runtime:jar:3.3 ? (antlr is wierd IIRC - so this is
probably not in this case)
[INFO] +- org.antlr:stringtemplate:jar:3.2.1:compile
[INFO] +- antlr:*antlr:jar:2.7.7*:compile
*Incident* 2: maybe antlr:antlr:jar:2.7.7 is a subset of
org.antlr:antlr-runtime:jar:3.3 ? (antlr is wierd IIRC - so this is
probably not in this case)
In general, dependencies with a non-namespaced groupId need to be
upgraded if possible.
[INFO] +- org.antlr:gunit:jar:3.3:test
[INFO] +- org.eclipse.jdt.core.compiler:ecj:jar:3.5.1:compile
[INFO] +- janino:janino:jar:2.5.15:compile
Note that janino is optional (output doesn't show that :( ) - no
problem here
[INFO] +- org.mvel:mvel2:jar:2.1-SNAPSHOT:compile
[INFO] +- com.thoughtworks.xstream:xstream:jar:1.3.1:test
[INFO] | \- xpp3:xpp3_min:jar:1.1.4c:test
[INFO] +- org.mortbay.*jetty*:jetty-embedded:jar:6.1.15:test
*Incident* 3: Wierd that drools-compiler would need jetty to test something?
[INFO] | +- org.mortbay.jetty:jetty:jar:6.1.15:test
[INFO] | | +- org.mortbay.jetty:jetty-util:jar:6.1.15:test
[INFO] | | \- org.mortbay.jetty:servlet-api:jar:2.5-20081211:test
[INFO] | \- javax.servlet.jsp:jsp-api:jar:2.1:test
[INFO] +- org.opensymphony.quartz:quartz:jar:1.6.1:test
[INFO] +- com.sun.xml.bind:jaxb-xjc:jar:2.2.1.1:provided
[INFO] +- com.sun.xml.bind:jaxb-impl:jar:2.2.1.1:provided
[INFO] +- javax.xml.bind:jaxb-api:jar:2.2.1:provided
[INFO] +- javax.xml.stream:stax-api:jar:1.0-2:provided
[INFO] +- javax.activation:activation:jar:1.1:provided
[INFO] +- net.java.dev.*glazedlists*:glazedlists_java15:jar:1.8.0:test
*Incident* 4: Wierd that drools-compiler would need a swing framework to
test something?
[INFO] +- junit:junit:jar:4.8.1:test
[INFO] \- org.mockito:mockito-all:jar:1.8.2:test
[INFO]
------------------------------------------------------------------------
[INFO] BUILD SUCCESS
[INFO]
------------------------------------------------------------------------
[INFO] Total time: 1.951s
[INFO] Finished at: Wed May 11 15:09:09 CEST 2011
[INFO] Final Memory: 10M/309M
[INFO]
------------------------------------------------------------------------
Here's another example showing another type of incident:
drools-camel-server [master] $ mvn dependency:tree
...
[INFO] +- org.drools:drools-grid-impl:jar:5.3.0-SNAPSHOT:compile
[INFO] | +- org.apache.mina:mina-core:jar:2.0.1:compile (version
managed from 2.0.0-M6)
[INFO] | \- com.hazelcast:hazelcast:jar:1.8.5:compile
...
[INFO] +- org.apache.camel:camel-cxf:jar:2.4.0:compile
[INFO] | \- org.apache.cxf:*cxf-rt-frontend-jaxrs*:jar:2.2.9:compile
[INFO] | +- org.apache.cxf:cxf-common-utilities:jar:2.2.9:compile
[INFO] | +- org.apache.cxf:cxf-rt-transports-http:jar:2.2.9:compile
[INFO] | +- org.apache.cxf:cxf-rt-databinding-aegis:jar:2.2.9:compile
[INFO] | +- jaxen:jaxen:jar:1.1.1:compile
[INFO] | \- org.apache.xmlbeans:xmlbeans:jar:2.4.0:compile
...
[INFO] +- org.apache.cxf:*cxf-bundle-jaxrs*:jar:2.2.9:compile
*Incident* A: This cxf-bundle-jaxrs is an uber jar. */Uber jars (as
dependencies) are evil./*
An uber jar extracts the classes from other jars and zips them
(=aggregate) in itself.
This effectively kills maven's ability to only have 1 class of
something in your classpath.
It turns your classpath into box of chocolates: /you never know
what version of class file you'll get/.
Also, it bloats the classpath with things you don't need (like
jetty in this case)
and those cause havoc if you deploy it to some app servers.
[INFO] | +- aopalliance:aopalliance:jar:1.0:compile
[INFO] | +-
org.apache.geronimo.specs:geronimo-annotation_1.0_spec:jar:1.1.1:compile
[INFO] | +-
org.apache.geronimo.specs:geronimo-stax-api_1.0_spec:jar:1.0.1:compile
[INFO] | +- wsdl4j:wsdl4j:jar:1.6.2:compile
[INFO] | +- org.apache.ws.commons.schema:XmlSchema:jar:1.4.5:compile
[INFO] | +- commons-lang:commons-lang:jar:2.4:compile
[INFO] | +-
org.apache.geronimo.specs:geronimo-activation_1.1_spec:jar:1.0.2:compile
[INFO] | +- org.codehaus.woodstox:wstx-asl:jar:3.2.9:compile
[INFO] | +- org.apache.neethi:neethi:jar:2.0.4:compile
[INFO] | +-
org.apache.geronimo.specs:geronimo-javamail_1.4_spec:jar:1.6:compile
[INFO] | +- org.springframework:spring-web:jar:2.5.6:compile
[INFO] | +- org.mortbay.jetty:*jetty*:jar:6.1.21:compile
[INFO] | +- org.mortbay.jetty:jetty-util:jar:6.1.21:compile
[INFO] | +- javax.ws.rs:jsr311-api:jar:1.0:compile
[INFO] | +- org.apache.abdera:abdera-core:jar:1.0:compile
[INFO] | +- org.apache.abdera:abdera-i18n:jar:1.0:compile
[INFO] | +- commons-codec:commons-codec:jar:1.3:compile
[INFO] | +- org.apache.abdera:abdera-parser:jar:1.0:compile
[INFO] | +- org.apache.ws.commons.axiom:axiom-impl:jar:1.2.7:compile
[INFO] | +- org.apache.ws.commons.axiom:axiom-api:jar:1.2.7:compile
[INFO] | +- org.apache.abdera:abdera-extensions-json:jar:1.0:compile
[INFO] | \- org.apache.abdera:abdera-extensions-main:jar:1.0:compile
...
Also, if you're trying to solve such things on master, try upgrading the
dependencies first (not on a release branch - upgrading is risky!):
many issues in the poms tend to be identified and fixed in newer versions.
--
With kind regards,
Geoffrey De Smet