PMD 6.16.0 released

30 June 2019

30-June-2019 - 6.16.0

The PMD team is pleased to announce PMD 6.16.0.

This is a minor release.

Table Of Contents

New and noteworthy

Updated PMD Designer

This PMD release ships a new version of the pmd-designer. For the changes, see PMD Designer Changelog.

PLSQL Grammar Updates

The grammar has been updated to support inline constraints in CREATE TABLE statements. Additionally, the CREATE TABLE statement may now be followed by physical properties and table properties. However, these properties are skipped over during parsing.

The CREATE VIEW statement now supports subquery views.

The EXTRACT function can now be parsed correctly. It is used to extract values from a specified datetime field. Also date time literals are parsed now correctly.

The CASE expression can now be properly used within SELECT statements.

Table aliases are now supported when specifying columns in INSERT INTO clauses.

New Rules

  • The Java rule DoubleBraceInitialization (java-bestpractices) detects non static initializers in anonymous classes also known as “double brace initialization”. This can be problematic, since a new class file is generated and object holds a strong reference to the surrounding class.

    Note: This rule is also part of the Java quickstart ruleset (rulesets/java/quickstart.xml).

Modified Rules

  • The Java rule UnusedPrivateField (java-bestpractices) now ignores by default fields, that are annotated with the Lombok experimental annotation @Delegate. This can be customized with the property ignoredAnnotations.

  • The Java rule SingularField (java-design) now ignores by default fields, that are annotated with the Lombok experimental annotation @Delegate. This can be customized with the property ignoredAnnotations.

  • The Java rules UnsynchronizedStaticFormatter and UnsynchronizedStaticDateFormatter (java-multithreading) now prefer synchronized blocks by default. They will raise a violation, if the synchronization is implemented on the method level. To allow the old behavior, the new property allowMethodLevelSynchronization can be enabled.

  • The Java rule UseUtilityClass (java-design) has a new property ignoredAnnotations. By default, classes that are annotated with Lombok’s @UtilityClass are ignored now.

  • The Java rule NonStaticInitializer (java-errorprone) does not report non static initializers in anonymous classes anymore. For this use case, there is a new rule now: DoubleBraceInitialization (java-bestpractices).

  • The Java rule CommentDefaultAccessModifier (java-errorprone) now by default searches for any unclosed java.lang.AutoCloseable resource. This includes now the standard*Stream classes. Previously only SQL-related resources were considered by this rule. The types can still be configured via the types property. Some resources do not need to be closed (e.g. ByteArrayOutputStream). These exceptions can be configured via the new property allowedResourceTypes. In order to restore the old behaviour, just remove the type java.lang.AutoCloseable from the types property and keep the remaining SQL-related classes.

Deprecated Rules

  • The Java rule AvoidFinalLocalVariable (java-codestyle) has been deprecated and will be removed with PMD 7.0.0. The rule is controversial and also contradicts other existing rules such as LocalVariableCouldBeFinal. If the goal is to avoid defining constants in a scope smaller than the class, then the rule AvoidDuplicateLiterals should be used instead.

Fixed Issues

  • apex
    • #1664: [apex] False positive ApexSharingViolationsRule, unsupported Apex feature
  • java
    • #1848: [java] Local classes should preserve their modifiers
  • java-bestpractices
    • #1703: [java] UnusedPrivateField on member annotated with lombok @Delegate
    • #1845: [java] Regression in MethodReturnsInternalArray not handling enums
    • #1854: [java] Rule to check for double brace initialisation
  • java-codestyle
    • #1612: [java] Deprecate AvoidFinalLocalVariable
    • #1880: [java] CommentDefaultAccessModifier should be configurable for top-level classes
  • java-design
    • #1094: [java] UseUtilityClass should be LombokAware
  • java-errorprone
    • #1000: [java] The rule CloseResource should deal with IO stream as default
    • #1853: [java] False positive for NonStaticInitializer in anonymous class
  • java-multithreading
    • #1814: [java] UnsynchronizedStaticFormatter documentation and implementation wrong
    • #1815: [java] False negative in UnsynchronizedStaticFormatter
  • plsql
    • #1828: [plsql] Parentheses stopped working
    • #1850: [plsql] Parsing errors with INSERT using returning or records and TRIM expression
    • #1873: [plsql] Expression list not working
    • #1878: [pslql] ParseException when parsing USING
    • #1879: [pslql] ParseException when parsing LEFT JOIN

API Changes

Deprecated APIs

Reminder: Please don’t use members marked with the annotation InternalApi, as they will likely be removed, hidden, or otherwise intentionally broken with 7.0.0.


As part of the changes we’d like to do to AST classes for 7.0.0, we would like to hide some methods and constructors that rule writers should not have access to. The following usages are now deprecated in the Java AST (with other languages to come):

  • Manual instantiation of nodes. Constructors of node classes are deprecated and marked InternalApi. Nodes should only be obtained from the parser, which for rules, means that never need to instantiate node themselves. Those constructors will be made package private with 7.0.0.
  • Subclassing of abstract node classes, or usage of their type. Version 7.0.0 will bring a new set of abstractions that will be public API, but the base classes are and will stay internal. You should not couple your code to them.
    • In the meantime you should use interfaces like JavaNode or Node, or the other published interfaces in this package, to refer to nodes generically.
    • Concrete node classes will be made final with 7.0.0.
  • Setters found in any node class or interface. Rules should consider the AST immutable. We will make those setters package private with 7.0.0.

Please look at to find out the full list of deprecations.

External Contributions