##### Overview

- Download PMD 5.0.4
- What's new in PMD 5.0.4
- PMD in the news
- PMD-related products and books
- Best practices
- Future directions
- Similar projects
- Credits
- License
- What does 'PMD' mean?

##### Usage

- Installation
- Command line usage
- Ant task usage
- Maven plugin usage
- Mvn plugin usage
- IDE plugin usage
- Suppressing warnings
- Finding duplicated code
- JSP support

##### Customizing PMD

- Compiling PMD
- How to write a rule
- Writing XPath rules
- How to make a rule set
- How it works
- Rule guidelines
- PMD developers information
- PMD Release Process

##### For example

- Run PMD on a Sourceforge project

##### Misc.

- XPath tutorial (Gregorian)

##### Rule Sets

- ecmascript
  - Basic Ecmascript
  - Braces
  - Unnecessary
- java
  - Android
  - Basic
  - Braces
  - Clone Implementation
  - Code Size
  - Comments
  - Controversial
  - Coupling
  - Design
  - Empty Code
  - Finalizer
  - Import Statements
  - J2EE
  - JavaBeans
  - JUnit
  - Jakarta Commons Logging
  - Java Logging
  - Migration
  - Naming
  - Optimization
  - Strict Exceptions
  - String and StringBuffer
  - Security Code Guidelines
  - Type Resolution
  - Unnecessary
  - Unused Code
- jsp
  - Basic JSF
  - Basic JSP
- xml
  - Basic XML
- xsl
  - XPath in XSL

##### Project Documentation

- Project Information
- Project Reports

## Security Code Guidelines

These rules check the security guidelines from Sun, published at http://java.sun.com/security/seccodeguide.html#gcg

### MethodReturnsInternalArray

Since: PMD 2.2

Exposing internal arrays to the caller violates object encapsulation since elements can be removed or replaced outside of the object that owns it. It is safer to return a copy of the array.

This rule is defined by the following Java class: net.sourceforge.pmd.lang.java.rule.sunsecure.MethodReturnsInternalArrayRule

Example(s):

    public class SecureSystem {
      UserData [] ud;
      public UserData [] getUserData() {
          // Don't return directly the internal array, return a copy
          return ud;
      }
    }

This rule has the following properties:

Name | Default Value | Description
violationSuppressRegex |  | Suppress violations with messages matching a regular expression
violationSuppressXPath |  | Suppress violations on nodes which match a given relative XPath expression.

### ArrayIsStoredDirectly

Since: PMD 2.2

Constructors and methods receiving arrays should clone objects and store the copy. This prevents future changes from the user from affecting the original array.

This rule is defined by the following Java class: net.sourceforge.pmd.lang.java.rule.sunsecure.ArrayIsStoredDirectlyRule

Example(s):

    public class Foo {
      private String [] x;
        public void foo (String [] param) {
          // Don't do this, make a copy of the array at least
          this.x=param;
        }
    }

This rule has the following properties:

Name | Default Value | Description
violationSuppressRegex |  | Suppress violations with messages matching a regular expression
violationSuppressXPath |  | Suppress violations on nodes which match a given relative XPath expression.