checkers.util

Class TreeUtils

@NonNull java.lang.Object

checkers.util.TreeUtils

public final class TreeUtils
extends @NonNull Object

A utility class made for helping to analyze a given Tree.

Method Summary

Methods

Modifier and Type	Method and Description
static Set<Tree.Kind>	classTreeKinds()
static boolean	containsThisConstructorInvocation(@Nullable MethodTree node)
static TypeElement	elementFromDeclaration(@Nullable ClassTree node) Gets the element for a class corresponding to a declaration.
static @NonNull ExecutableElement	elementFromDeclaration(@Nullable MethodTree node) Gets the element for a method corresponding to a declaration.
static VariableElement	elementFromDeclaration(VariableTree node) Gets the element for a variable corresponding to its declaration.
static @Nullable Element	elementFromUse(ExpressionTree node) Gets the element for the declaration corresponding to this use of an element.
static @NonNull ExecutableElement	elementFromUse(MethodInvocationTree node)
static @NonNull ExecutableElement	elementFromUse(NewClassTree node)
static @Nullable ClassTree	enclosingClass(@Nullable TreePath path) Gets the enclosing class of the tree node defined by the given {@link TreePath}.
static @Nullable MethodTree	enclosingMethod(@Nullable TreePath path) Gets the enclosing method of the tree node defined by the given {@link TreePath}.
static <T extends @Nullable Tree> T	enclosingOfClass(@Nullable TreePath path, Class<T> treeClass) Gets the first enclosing tree in path, of the specified class
static @Nullable Tree	enclosingOfKind(@Nullable TreePath path, Set<Tree.Kind> kinds) Gets the first enclosing tree in path, with any one of the specified kinds.
static @Nullable Tree	enclosingOfKind(@Nullable TreePath path, Tree.Kind kind) Gets the first enclosing tree in path, of the specified kind.
static @Nullable BlockTree	enclosingTopLevelBlock(@Nullable TreePath path)
static VariableTree	enclosingVariable(@Nullable TreePath path) Gets the enclosing variable of a tree node defined by the given TreePath.
static @Nullable Tree	firstStatement(@Nullable Tree tree)
static @Nullable Tree	getAssignmentContext(@Nullable TreePath treePath) Returns the tree with the assignment context for the treePath leaf node.
static VariableElement	getField(@ReadOnly String typeName, @ReadOnly String fieldName, ProcessingEnvironment env) Returns the VariableElement for a field declaration.
static @NonNull ExecutableElement	getMethod(@ReadOnly String typeName, @ReadOnly String methodName, int params, ProcessingEnvironment env) Returns the ExecutableElement for a method declaration of methodName, in class typeName, with params parameters.
static ExpressionTree	getReceiverTree(ExpressionTree expression) Returns the receiver tree of a field access or a method invocation
static boolean	hasExplicitConstructor(@Nullable ClassTree node) Determine whether the given class contains an explicit constructor.
static boolean	isClassTree(Tree.Kind kind)
static boolean	isCompileTimeString(ExpressionTree node) Returns true if the node is a constant-time expression.
static boolean	isConstructor(@Nullable MethodTree tree) Checks if the provided method is a constructor method or no.
static boolean	isDiamondTree(@Nullable Tree tree) Returns true if the tree is of a diamond type
static boolean	isEnumSuper(MethodInvocationTree node)
static boolean	isExpressionTree(@Nullable Tree tree) Determine whether the given tree represents an ExpressionTree.
static boolean	isFieldAccess(@Nullable Tree tree, VariableElement var, ProcessingEnvironment env) Returns true if the given tree represents an access of the given VariableElement.
static boolean	isMethodInvocation(@Nullable Tree tree, @NonNull ExecutableElement method, ProcessingEnvironment env) Returns true if the given element is an invocation of the method, or of any method that overrides that one.
static boolean	isStringCompoundConcatenation(CompoundAssignmentTree tree) Returns true if the compound assignment tree is a string concatenation
static boolean	isStringConcatenation(@Nullable Tree tree) Returns true if the tree represents a String concatenation operation
static boolean	isSuperCall(MethodInvocationTree tree) Checks if the method invocation is a call to super.
static boolean	isUseOfElement(ExpressionTree node) Determine whether the given ExpressionTree has an underlying element.
static @Nullable Name	methodName(MethodInvocationTree node)
static @Nullable TreePath	pathTillClass(@Nullable TreePath path) Gets path to the the first enclosing class tree, where class is defined by the classTreeKinds method.
static @Nullable TreePath	pathTillOfKind(@Nullable TreePath path, Set<Tree.Kind> kinds) Gets path to the the first enclosing tree with any one of the specified kinds.
static @Nullable TreePath	pathTillOfKind(@Nullable TreePath path, Tree.Kind kind) Gets path to the the first enclosing tree of the specified kind.
static ExpressionTree	skipParens(ExpressionTree tree) If the given tree is a parenthesized tree, it returns the enclosed non-parenthesized tree.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Detail

isConstructor

public static boolean isConstructor(@Nullable MethodTree tree)

Checks if the provided method is a constructor method or no.

Parameters:

tree - a tree defining the method

Returns:

true iff tree describes a constructor

isSuperCall

public static boolean isSuperCall(MethodInvocationTree tree)

Checks if the method invocation is a call to super.

Parameters:

tree - a tree defining a method invocation

Returns:

true iff tree describes a call to super

enclosingOfKind

public static @Nullable Tree enclosingOfKind(@Nullable TreePath path,
                             Tree.Kind kind)

Gets the first enclosing tree in path, of the specified kind.

Parameters:

path - the path defining the tree node

kind - the kind of the desired tree

Returns:

the enclosing tree of the given type as given by the path

enclosingOfKind

public static @Nullable Tree enclosingOfKind(@Nullable TreePath path,
                             Set<Tree.Kind> kinds)

Gets the first enclosing tree in path, with any one of the specified kinds.

Parameters:

path - the path defining the tree node

kinds - the set of kinds of the desired tree

Returns:

the enclosing tree of the given type as given by the path

pathTillClass

public static @Nullable TreePath pathTillClass(@Nullable TreePath path)

Gets path to the the first enclosing class tree, where class is defined by the classTreeKinds method.

Parameters:

path - the path defining the tree node

Returns:

the path to the enclosing class tree

pathTillOfKind

public static @Nullable TreePath pathTillOfKind(@Nullable TreePath path,
                                Tree.Kind kind)

Gets path to the the first enclosing tree of the specified kind.

Parameters:

path - the path defining the tree node

kind - the kind of the desired tree

Returns:

the path to the enclosing tree of the given type

pathTillOfKind

public static @Nullable TreePath pathTillOfKind(@Nullable TreePath path,
                                Set<Tree.Kind> kinds)

Gets path to the the first enclosing tree with any one of the specified kinds.

Parameters:

path - the path defining the tree node

kinds - the set of kinds of the desired tree

Returns:

the path to the enclosing tree of the given type

enclosingOfClass

public static <T extends @Nullable Tree> T enclosingOfClass(@Nullable TreePath path,
                                            Class<T> treeClass)

Gets the first enclosing tree in path, of the specified class

Parameters:

path - the path defining the tree node

treeClass - the class of the desired tree

Returns:

the enclosing tree of the given type as given by the path

enclosingClass

public static @Nullable ClassTree enclosingClass(@Nullable TreePath path)

Gets the enclosing class of the tree node defined by the given {@link TreePath}. It returns a Tree, from which AnnotatedTypeMirror or Element can be obtained.

Parameters:

path - the path defining the tree node

Returns:

the enclosing class (or interface) as given by the path, or null if one does not exist.

enclosingVariable

public static VariableTree enclosingVariable(@Nullable TreePath path)

Gets the enclosing variable of a tree node defined by the given TreePath.

Parameters:

path - the path defining the tree node

Returns:

the enclosing variable as given by the path, or null if one does not exist

enclosingMethod

public static @Nullable MethodTree enclosingMethod(@Nullable TreePath path)

Gets the enclosing method of the tree node defined by the given {@link TreePath}. It returns a Tree, from which an AnnotatedTypeMirror or Element can be obtained.

Parameters:

path - the path defining the tree node

Returns:

the enclosing method as given by the path, or null if one does not exist

enclosingTopLevelBlock

public static @Nullable BlockTree enclosingTopLevelBlock(@Nullable TreePath path)

skipParens

public static ExpressionTree skipParens(ExpressionTree tree)

If the given tree is a parenthesized tree, it returns the enclosed non-parenthesized tree. Otherwise, it returns the same tree.

Parameters:

tree - an expression tree

Returns:

the outermost non-parenthesized tree enclosed by the given tree

getAssignmentContext

public static @Nullable Tree getAssignmentContext(@Nullable TreePath treePath)

Returns the tree with the assignment context for the treePath leaf node. The assignment context for the treepath is the most enclosing tree of type:

• AssignmentTree
• CompoundAssignmentTree
• MethodInvocationTree
• NewArrayTree
• NewClassTree
• ReturnTree
• VariableTree

Parameters:

treePath -

Returns:

the assignment context as described.

elementFromDeclaration

public static final TypeElement elementFromDeclaration(@Nullable ClassTree node)

Gets the element for a class corresponding to a declaration.

Parameters:

node -

Returns:

the element for the given class

elementFromDeclaration

public static final @NonNull ExecutableElement elementFromDeclaration(@Nullable MethodTree node)

Gets the element for a method corresponding to a declaration.

Parameters:

node -

Returns:

the element for the given method

elementFromDeclaration

public static final VariableElement elementFromDeclaration(VariableTree node)

Gets the element for a variable corresponding to its declaration.

Parameters:

node -

Returns:

the element for the given variable

elementFromUse

public static final @Nullable Element elementFromUse(ExpressionTree node)

Gets the element for the declaration corresponding to this use of an element. To get the element for a declaration, use Trees.getElement(TreePath) instead. TODO: remove this method, as it really doesn't do anything.

Parameters:

node - the tree corresponding to a use of an element

Returns:

the element for the corresponding declaration

elementFromUse

public static final @NonNull ExecutableElement elementFromUse(MethodInvocationTree node)

elementFromUse

public static final @NonNull ExecutableElement elementFromUse(NewClassTree node)

isUseOfElement

public static final boolean isUseOfElement(ExpressionTree node)

Determine whether the given ExpressionTree has an underlying element.

Parameters:

node - the ExpressionTree to test

Returns:

whether the tree refers to an identifier, member select, or method invocation.

methodName

public static final @Nullable Name methodName(MethodInvocationTree node)

Returns:

the name of the invoked method

containsThisConstructorInvocation

public static final boolean containsThisConstructorInvocation(@Nullable MethodTree node)

Returns:

true if the first statement in the body is a self constructor invocation within a constructor

firstStatement

public static final @Nullable Tree firstStatement(@Nullable Tree tree)

hasExplicitConstructor

public static boolean hasExplicitConstructor(@Nullable ClassTree node)

Determine whether the given class contains an explicit constructor.

Parameters:

node - A class tree.

Returns:

True, iff there is an explicit constructor.

isDiamondTree

public static final boolean isDiamondTree(@Nullable Tree tree)

Returns true if the tree is of a diamond type

isStringConcatenation

public static final boolean isStringConcatenation(@Nullable Tree tree)

Returns true if the tree represents a String concatenation operation

isStringCompoundConcatenation

public static final boolean isStringCompoundConcatenation(CompoundAssignmentTree tree)

Returns true if the compound assignment tree is a string concatenation

isCompileTimeString

public static boolean isCompileTimeString(ExpressionTree node)

Returns true if the node is a constant-time expression. A tree is a constant-time expression if it is:

1. a literal tree
2. a reference to a final variable initialized with a compile time constant
3. a String concatenation of two compile time constants

getReceiverTree

public static ExpressionTree getReceiverTree(ExpressionTree expression)

Returns the receiver tree of a field access or a method invocation

classTreeKinds

public static Set<Tree.Kind> classTreeKinds()

isClassTree

public static boolean isClassTree(Tree.Kind kind)

isMethodInvocation

public static boolean isMethodInvocation(@Nullable Tree tree,
                         @NonNull ExecutableElement method,
                         ProcessingEnvironment env)

Returns true if the given element is an invocation of the method, or of any method that overrides that one.

getMethod

public static @NonNull ExecutableElement getMethod(@ReadOnly String typeName,
                                   @ReadOnly String methodName,
                                   int params,
                                   ProcessingEnvironment env)

Returns the ExecutableElement for a method declaration of methodName, in class typeName, with params parameters. TODO: to precisely resolve method overloading, we should use parameter types and not just the number of parameters!

isFieldAccess

public static boolean isFieldAccess(@Nullable Tree tree,
                    VariableElement var,
                    ProcessingEnvironment env)

Returns true if the given tree represents an access of the given VariableElement.

getField

public static VariableElement getField(@ReadOnly String typeName,
                       @ReadOnly String fieldName,
                       ProcessingEnvironment env)

Returns the VariableElement for a field declaration.

Parameters:

typeName - the class where the field is declared.

fieldName - the name of the field.

env - the processing environment.

Returns:

the VariableElement for typeName.fieldName

isExpressionTree

public static boolean isExpressionTree(@Nullable Tree tree)

Determine whether the given tree represents an ExpressionTree. TODO: is there a nicer way than an instanceof?

Parameters:

tree - the Tree to test.

Returns:

whether the tree is an ExpressionTree

isEnumSuper

public static boolean isEnumSuper(MethodInvocationTree node)

Parameters:

node - the method invocation to check

Returns:

true if this is a super call to the Enum constructor