Package org.codehaus.groovy.control

Class LabelVerifier

java.lang.Object

org.codehaus.groovy.ast.CodeVisitorSupport

org.codehaus.groovy.ast.ClassCodeVisitorSupport

org.codehaus.groovy.control.LabelVerifier

All Implemented Interfaces:

GroovyClassVisitor, GroovyCodeVisitor, ErrorCollecting

public class LabelVerifier
extends ClassCodeVisitorSupport

This class checks the handling of labels in the AST

Constructor Summary

Constructors

Constructor	Description
LabelVerifier(SourceUnit src)	Creates a verifier for label usage in one source unit.

Method Summary

Modifier and Type	Method	Description
protected void	assertNoLabelsMissed()	Reports any labeled break or continue statements that could not be matched.
protected SourceUnit	getSourceUnit()	Returns the source unit currently being verified.
protected void	postVisitStatement(Statement s)	Removes any labels that go out of scope after visiting the current statement.
void	visitAssertStatement(AssertStatement statement)	Visits an assert statement and then runs post-visit bookkeeping.
void	visitBlockStatement(BlockStatement statement)	Visits a block statement and then runs post-visit bookkeeping.
void	visitBreakStatement(BreakStatement breakStatement)	Verifies that a break statement appears in a valid context.
void	visitCaseStatement(CaseStatement statement)	Visits a case statement and then runs post-visit bookkeeping.
void	visitCatchStatement(CatchStatement statement)	Visits a catch statement and then runs post-visit bookkeeping.
protected void	visitClassCodeContainer(Statement code)	Resets label-tracking state before verifying a class code block.
void	visitClosureExpression(ClosureExpression expression)	Visits a ClosureExpression with annotation processing, traversing parameter annotations before delegating to parent traversal.
void	visitContinueStatement(ContinueStatement continueStatement)	Verifies that a continue statement appears in a valid loop context.
void	visitDoWhileLoop(DoWhileStatement loop)	Verifies labels inside a do/while loop.
void	visitEmptyStatement(EmptyStatement statement)	Visits an empty statement and then runs post-visit bookkeeping.
void	visitExpressionStatement(ExpressionStatement statement)	Visits an expression statement and then runs post-visit bookkeeping.
void	visitForLoop(ForStatement loop)	Verifies labels inside a for loop.
void	visitIfElse(IfStatement cond)	Verifies labels inside an if/else statement.
void	visitLambdaExpression(LambdaExpression expression)	Visits a LambdaExpression, treating it as a closure expression.
void	visitReturnStatement(ReturnStatement statement)	Visits a return statement and then runs post-visit bookkeeping.
protected void	visitStatement(Statement s)	Registers any labels introduced by the current statement.
void	visitSwitch(SwitchStatement switchStatement)	Verifies labels inside a switch statement.
void	visitSwitchExpression(SwitchExpression expression)	Verifies labels and yield inside a switch expression (GROOVY-12255).
void	visitSynchronizedStatement(SynchronizedStatement statement)	Visits a synchronized statement and then runs post-visit bookkeeping.
void	visitThrowStatement(ThrowStatement statement)	Visits a throw statement and then runs post-visit bookkeeping.
void	visitTryCatchFinally(TryCatchStatement statement)	Visits a try-catch-finally statement and then runs post-visit bookkeeping.
void	visitWhileLoop(WhileStatement loop)	Verifies labels inside a while loop.
void	visitYieldStatement(YieldStatement statement)	Verifies that a yield statement targets the innermost switch expression and does not cross a closure or lambda that was entered after that switch (GROOVY-12255 / JEP 361).

Methods inherited from class org.codehaus.groovy.ast.ClassCodeVisitorSupport

addError, visitAnnotation, visitAnnotations, visitAnnotations, visitClass, visitConstructor, visitConstructorOrMethod, visitDeclarationExpression, visitField, visitImports, visitMethod, visitObjectInitializerStatements, visitPackage, visitProperty, visitStatementAnnotations

Methods inherited from class org.codehaus.groovy.ast.CodeVisitorSupport

afterSwitchCaseStatementsVisited, afterSwitchCaseStatementsVisited, afterSwitchConditionExpressionVisited, afterSwitchConditionExpressionVisited, visitArgumentlistExpression, visitArrayExpression, visitAttributeExpression, visitBinaryExpression, visitBitwiseNegationExpression, visitBooleanExpression, visitBytecodeExpression, visitCastExpression, visitClassExpression, visitClosureListExpression, visitConstantExpression, visitConstructorCallExpression, visitFieldExpression, visitGStringExpression, visitListExpression, visitMapEntryExpression, visitMapExpression, visitMethodCallExpression, visitMethodPointerExpression, visitMethodReferenceExpression, visitNotExpression, visitPostfixExpression, visitPrefixExpression, visitPropertyExpression, visitRangeExpression, visitShortTernaryExpression, visitSpreadExpression, visitSpreadMapExpression, visitStaticMethodCallExpression, visitTernaryExpression, visitTupleExpression, visitUnaryMinusExpression, visitUnaryPlusExpression, visitVariableExpression

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.codehaus.groovy.ast.GroovyCodeVisitor

visit, visit, visitEmptyExpression, visitListOfExpressions

Constructor Details

LabelVerifier

public LabelVerifier(SourceUnit src)

Creates a verifier for label usage in one source unit.

Parameters:

src - the source unit to report errors against

Method Details

getSourceUnit

protected SourceUnit getSourceUnit()

Returns the source unit currently being verified.

Specified by:

getSourceUnit in class ClassCodeVisitorSupport

Returns:

the active source unit

assertNoLabelsMissed

protected void assertNoLabelsMissed()

Reports any labeled break or continue statements that could not be matched.

visitStatement

protected void visitStatement(Statement s)

Registers any labels introduced by the current statement.

Parameters:

s - the statement being entered

postVisitStatement

protected void postVisitStatement(Statement s)

Removes any labels that go out of scope after visiting the current statement.

Parameters:

s - the statement being exited

visitClassCodeContainer

protected void visitClassCodeContainer(Statement code)

Resets label-tracking state before verifying a class code block.

Overrides:

visitClassCodeContainer in class ClassCodeVisitorSupport

Parameters:

code - the statement container to verify

visitIfElse

public void visitIfElse(IfStatement cond)

Verifies labels inside an if/else statement.

Specified by:

visitIfElse in interface GroovyCodeVisitor

Parameters:

cond - the conditional statement to inspect

visitForLoop

public void visitForLoop(ForStatement loop)

Verifies labels inside a for loop.

Specified by:

visitForLoop in interface GroovyCodeVisitor

Parameters:

loop - the loop to inspect

visitWhileLoop

public void visitWhileLoop(WhileStatement loop)

Verifies labels inside a while loop.

Specified by:

visitWhileLoop in interface GroovyCodeVisitor

Parameters:

loop - the loop to inspect

visitDoWhileLoop

public void visitDoWhileLoop(DoWhileStatement loop)

Verifies labels inside a do/while loop.

Specified by:

visitDoWhileLoop in interface GroovyCodeVisitor

Parameters:

loop - the loop to inspect

visitSwitch

public void visitSwitch(SwitchStatement switchStatement)

Verifies labels inside a switch statement.

Specified by:

visitSwitch in interface GroovyCodeVisitor

Parameters:

switchStatement - the switch statement to inspect

visitSwitchExpression

public void visitSwitchExpression(SwitchExpression expression)

Verifies labels and yield inside a switch expression (GROOVY-12255). Per JEP 361, break and continue cannot transfer control out of a switch expression, so the enclosing loop, switch, and label context does not flow into the arms; loops and labels declared inside an arm remain valid targets.

Specified by:

visitSwitchExpression in interface GroovyCodeVisitor

Overrides:

visitSwitchExpression in class CodeVisitorSupport

Parameters:

expression - the switch expression to inspect

Since:

6.0.0

visitYieldStatement

public void visitYieldStatement(YieldStatement statement)

Verifies that a yield statement targets the innermost switch expression and does not cross a closure or lambda that was entered after that switch (GROOVY-12255 / JEP 361). A switch expression that itself lives inside a closure (for example a GINQ query) is allowed.

Specified by:

visitYieldStatement in interface GroovyCodeVisitor

Overrides:

visitYieldStatement in class ClassCodeVisitorSupport

Parameters:

statement - the yield statement to inspect

Since:

6.0.0

visitClosureExpression

public void visitClosureExpression(ClosureExpression expression)

Description copied from class: ClassCodeVisitorSupport

Visits a ClosureExpression with annotation processing, traversing parameter annotations before delegating to parent traversal.

Specified by:

visitClosureExpression in interface GroovyCodeVisitor

Overrides:

visitClosureExpression in class ClassCodeVisitorSupport

Parameters:

expression - the closure expression to visit

visitLambdaExpression

public void visitLambdaExpression(LambdaExpression expression)

Description copied from class: CodeVisitorSupport

Visits a LambdaExpression, treating it as a closure expression.

Specified by:

visitLambdaExpression in interface GroovyCodeVisitor

Overrides:

visitLambdaExpression in class CodeVisitorSupport

Parameters:

expression - the lambda expression

visitBreakStatement

public void visitBreakStatement(BreakStatement breakStatement)

Verifies that a break statement appears in a valid context.

Specified by:

visitBreakStatement in interface GroovyCodeVisitor

Parameters:

breakStatement - the break statement to inspect

visitContinueStatement

public void visitContinueStatement(ContinueStatement continueStatement)

Verifies that a continue statement appears in a valid loop context.

Specified by:

visitContinueStatement in interface GroovyCodeVisitor

Parameters:

continueStatement - the continue statement to inspect

visitAssertStatement

public void visitAssertStatement(AssertStatement statement)

Visits an assert statement and then runs post-visit bookkeeping.

Specified by:

visitAssertStatement in interface GroovyCodeVisitor

Overrides:

visitAssertStatement in class ClassCodeVisitorSupport

Parameters:

statement - the statement to visit

visitBlockStatement

public void visitBlockStatement(BlockStatement statement)

Visits a block statement and then runs post-visit bookkeeping.

Specified by:

visitBlockStatement in interface GroovyCodeVisitor

Overrides:

visitBlockStatement in class ClassCodeVisitorSupport

Parameters:

statement - the statement to visit

See Also:

• CodeVisitorSupport.visitForLoop(ForStatement)
• CodeVisitorSupport.visitWhileLoop(WhileStatement)

visitCaseStatement

public void visitCaseStatement(CaseStatement statement)

Visits a case statement and then runs post-visit bookkeeping.

Specified by:

visitCaseStatement in interface GroovyCodeVisitor

Overrides:

visitCaseStatement in class ClassCodeVisitorSupport

Parameters:

statement - the statement to visit

visitCatchStatement

public void visitCatchStatement(CatchStatement statement)

Visits a catch statement and then runs post-visit bookkeeping.

Specified by:

visitCatchStatement in interface GroovyCodeVisitor

Overrides:

visitCatchStatement in class ClassCodeVisitorSupport

Parameters:

statement - the statement to visit

visitEmptyStatement

public void visitEmptyStatement(EmptyStatement statement)

Visits an empty statement and then runs post-visit bookkeeping.

Specified by:

visitEmptyStatement in interface GroovyCodeVisitor

Overrides:

visitEmptyStatement in class CodeVisitorSupport

Parameters:

statement - the statement to visit

visitExpressionStatement

public void visitExpressionStatement(ExpressionStatement statement)

Visits an expression statement and then runs post-visit bookkeeping.

Specified by:

visitExpressionStatement in interface GroovyCodeVisitor

Overrides:

visitExpressionStatement in class ClassCodeVisitorSupport

Parameters:

statement - the statement to visit

visitReturnStatement

public void visitReturnStatement(ReturnStatement statement)

Visits a return statement and then runs post-visit bookkeeping.

Specified by:

visitReturnStatement in interface GroovyCodeVisitor

Overrides:

visitReturnStatement in class ClassCodeVisitorSupport

Parameters:

statement - the statement to visit

visitSynchronizedStatement

public void visitSynchronizedStatement(SynchronizedStatement statement)

Visits a synchronized statement and then runs post-visit bookkeeping.

Specified by:

visitSynchronizedStatement in interface GroovyCodeVisitor

Overrides:

visitSynchronizedStatement in class ClassCodeVisitorSupport

Parameters:

statement - the statement to visit

visitThrowStatement

public void visitThrowStatement(ThrowStatement statement)

Visits a throw statement and then runs post-visit bookkeeping.

Specified by:

visitThrowStatement in interface GroovyCodeVisitor

Overrides:

visitThrowStatement in class ClassCodeVisitorSupport

Parameters:

statement - the statement to visit

visitTryCatchFinally

public void visitTryCatchFinally(TryCatchStatement statement)

Visits a try-catch-finally statement and then runs post-visit bookkeeping.

Specified by:

visitTryCatchFinally in interface GroovyCodeVisitor

Overrides:

visitTryCatchFinally in class ClassCodeVisitorSupport

Parameters:

statement - the statement to visit