Adding custom rule to PMD - Class not found issue

[Adarsh Kashyap]

I am trying to execute this example shown here
http://pmd.sourceforge.net/pmd-5.3.0/customizing/howtowritearule.html

WhileLoopsMustUseBracesRule class not found is shown [one of the standard issue for beginners i believe]

Method tried :

1) cd pmd-5.3.0
2) created WhileLoopsMustUseBracesRule.java and ruleset.xml as per shown in the page.
3) javac -cp [all the required jar files seperated by ; since it is windows pc ] WhileLoopsMustUseBracesRule.java
4) bin/pmd.bat -d [code on which pmd has to check the rule] -f xml -R ruleset.xml

the above steps are giving me no class found error,here developer has commented saying these steps work [ http://sourceforge.net/p/pmd/discussion/188192/thread/7a34d224/ ]
Please let me know if i am missing anything.

I tired adding class file directly to classpath as well

Other methods tried :

1) compiled the WhileLoopsMustUseBracesRule.java file and got the .class file.
2) created a jar using jar -cf jar_name jar_file command
3) added that jar file in the class path , using set CLASSPATH and also tried adding directly in the batch file
i.e. java -classpath %TOPDIRECTORY%\lib*;newrule.jar %OPTS% %CLASSNAME%
something like this.

please help !

[Suman alungh]

Hi Adarsh,

I am a beginner and trying to follow what you did but I am having some problem. How did you manage to get the .class file. I can't compile my .java file. I created the exact WhileLoopsMustUseBracesRule.java file and the exact ruleset.xml and when I try to javac WhileLoopsMustUseBracesRule.java then it gives me below error. Can you please help.

javac WhileLoopsMustUseBracesRule.java
WhileLoopsMustUseBracesRule.java:1: error: package net.sourceforge.pmd.lang.ast
does not exist
import net.sourceforge.pmd.lang.ast.;
^
WhileLoopsMustUseBracesRule.java:2: error: package net.sourceforge.pmd.lang.jav
.ast does not exist
import net.sourceforge.pmd.lang.java.ast.;
^
WhileLoopsMustUseBracesRule.java:3: error: package net.sourceforge.pmd.lang.jav
.rule does not exist
import net.sourceforge.pmd.lang.java.rule.*;
^
WhileLoopsMustUseBracesRule.java:5: error: cannot find symbol
public class WhileLoopsMustUseBracesRule extends AbstractJavaRule {
^
symbol: class AbstractJavaRule
WhileLoopsMustUseBracesRule.java:6: error: cannot find symbol
public Object visit(ASTWhileStatement node, Object data) {
^
symbol: class ASTWhileStatement
location: class WhileLoopsMustUseBracesRule
WhileLoopsMustUseBracesRule.java:13: error: cannot find symbol
private boolean hasBlockAsFirstChild(Node node) {
^
symbol: class Node
location: class WhileLoopsMustUseBracesRule
WhileLoopsMustUseBracesRule.java:7: error: cannot find symbol
Node firstStmt = node.jjtGetChild(1);
^
symbol: class Node
location: class WhileLoopsMustUseBracesRule
WhileLoopsMustUseBracesRule.java:11: error: cannot find symbol
return super.visit(node,data);
^
symbol: variable super
location: class WhileLoopsMustUseBracesRule
WhileLoopsMustUseBracesRule.java:14: error: cannot find symbol
return (node.jjtGetNumChildren() != 0 && (node.jjtGetChild(0) instanceo
ASTBlock));

^
symbol: class ASTBlock
location: class WhileLoopsMustUseBracesRule
9 errors

[Adarsh Kashyap]

I found the solution!

Had to set CLASSPATH separately using

set CLASSPATH=path\to\my\classfile
and then in the batch i had to add %CLASSPATH% , otherwise using -cp was resetting the classpath i guess. This worked for me.

Thanks

[Nikhil Pawar]

Hey could you please tell me what exactly did you change in pmd.bat to set the classpath?

[Andreas Dangel]

You have the following options:

1. copy the jar file, which contains your custom rule, into the lib directory of the pmd-installation. That's all you need to do, all jar files will be picked up in the lib directory automatically.

2. Modify the file pmd.bat to have the following content. This directly adds C:\Path\To\Your\Custom\Rule to the classpath. This Path needs to contain the compiled class files for your custom rule.

   @echo off
   set TOPDIR=%~dp0..
   set OPTS=
   set MAIN_CLASS=net.sourceforge.pmd.PMD
   
   java -classpath %TOPDIR%\lib\*;C:\Path\To\Your\Custom\Rule %OPTS% %MAIN_CLASS% %*
   

3. Modify the file pmd.bat to set the environment variable CLASSPATH and use this variable later on:

   @echo off
   set TOPDIR=%~dp0..
   set OPTS=
   set MAIN_CLASS=net.sourceforge.pmd.PMD
   set CLASSPATH=C:\Path\To\Your\Custom\Rule
   
   java -classpath %TOPDIR%\lib\*;%CLASSPATH% %OPTS% %MAIN_CLASS% %*
   

   You could remove the set CLASSPATH=... line and set this environment variable outside of the pmd.bat file. This would have the advantage, that you don't need to adjust the pmd.bat file, if you change the classpath, but just change the environment variable.

Hope that helps :)