This page tracks the work in progress to add Java™ 8 support (mainly jsr308 "Type Annotations" and jsr335 "Lambda Expressions") into Eclipse JDT UI. See JDT Core/Java8 for the work in the JDT Core plug-ins.
|Lambda Expressions||Method references||Default Methods||Type Annotations / Receiver parameter|
|Refactoring operations (core)|
|Javadoc (hover, view)|
|Tested and works, but can be improved (e.g. by adding Quick Assists or Quick Fixes)|
|Not done yet|
(1) more work needed if spec changes
- set ASTProvider.SHARED_AST_LEVEL to JLS8 (bug 403927)
- fix problems that need immediate handling
- fix other references to JLS4
- Annotations on types
- Annotations that moved to another node in the AST (under discussion in bug 403834)
- MethodDeclaration#thrownExceptions() -> thrownExceptionsTypes() (bug 403924)
- Annotations on Extra Dimensions (bug 403923)
- Receiver parameter on instance methods and inner class constructors (bug 404147)
- Refactoring dialogs that allow to modify types
- deferred: Render annotations in Javadoc hover/view. Do not render in Outline, etc. for now. (bug 403917)
- Default Methods
- Lambda Expressions
- check code that walks the parent chain to find the enclosing Block or BodyDeclaration
- Method References
- The following lines must be added in all headers of modified files for Java™ 8 implementation:
* This is an implementation of an early-draft specification developed under the Java * Community Process (JCP) and is made available for testing and evaluation purposes * only. The code is not compatible with any specification of the JCP. *
- Use the following @since tag on all newly added members: "3.9 BETA_JAVA8"
Things to remember/caveats
- Goal of the first pass is to make Eclipse work with the new language features. For more advanced support (new quick fixes / refactorings / templates / ...), please file an enhancement request with the [1.8] tag.
- Bugs that went into the BETA_JAVA8 branch should be RESOLVED/FIXED with Target Milestone "BETA_JAVA8" and the [1.8] tag in front of the summary.
- For ASTNode changes:
- Search for references to a changed AST Node and update code that relies on the concrete structure
- Remember there are multiple ways to access AST node properties:
- via getter/setter or List-valued accessor
- via the StructuralPropertyDescriptor constant
- for properties declared in an abstract class: via get*Property() instance method
- Check references to superclasses of the changed/added node type. E.g. for IntersectionType, code that thinks it handles all known subtypes of Type needs to be adjusted.
- Add new node types to switch or if-else-if statements
- Think about cases where code could use StructuralPropertyDescriptors
- Think about cases where new bindings can show up.
DOM AST node changes in JLS8
If everything is correct, then you should find these as references to ASTNode#unsupportedIn2_3_4() and #supportedOnlyIn2_3_4().
+AnnotatableType (abstract superclass): +annotations: List<Annotation> (also in subtypes PrimitiveType, ArrayType, SimpleType, QualifiedType, WildcardType) +ExtraDimension +annotations: List<Annotation> +LambdaExpression: +parentheses: boolean +parameters: List<SingleVariableDeclaration> or List<VariableDeclarationFragment> +body: Block or Expression +resolveMethodBinding(): IMethodBinding ~MethodDeclaration: -setExtraDimensions(int) +extraDimensions: List<ExtraDimension> (incl. annotations on extra dimensions) +receiverType: AnnotatableType +receiverQualifier: SimpleName -thrownExceptions: List<Name> +thrownExceptionTypes: List<Type> ~SingleVariableDeclaration: +varargsAnnotations: List<Annotation> ~TypeParameter: +annotations: List<Annotation> ~VariableDeclaration: +extraDimensions List<ExtraDimension> (also in subtypes SingleVariableDeclaration, VariableDeclarationFragment)
For JLS4, the changes were:
~TryStatement: +resources: List<VariableDeclarationExpression> +UnionType +types: List<Type>
- 'default' flag:
- show in the UI?
- update JdtFlags?
- The ITypeBinding of a TYPE_USE-annotated expression (e.g. ClassInstanceCreation or reference to a variable) doesn't contain the TYPE_USE annotations. References to "String s" and "@NonEmpty String ns" have identical type bindings. Should TYPE_USE annotations show up in reference bindings? Note that for some expressions, the annotated type is not defined by jsr 308, e.g. for the conditional expression here:
@Deprecated @NonEmpty String s = new Random().nextBoolean() ? new @NonEmpty String("hi") : new String();
- A VariableDeclarationFragment can now also show up in a LambdaExpression
- check usages of VariableDeclarationFragment.getParent()
- check usages of VariableDeclarationFragment that assume there's an associated type (e.g. ASTNodes.getType(VariableDeclaration))
- Check helper methods in ASTNodes
- e.g. getTopMostName(Name) is not correct any more to find an exception type
- Check all ASTVisitors that override one of the visit/endVisit methods for one of the changed AST node types