Class CheckReturnValue

java.lang.Object

com.google.errorprone.bugpatterns.BugChecker

com.google.errorprone.bugpatterns.AbstractReturnValueIgnored

com.google.errorprone.bugpatterns.CheckReturnValue

All Implemented Interfaces:

BugChecker.ClassTreeMatcher, BugChecker.MemberReferenceTreeMatcher, BugChecker.MethodInvocationTreeMatcher, BugChecker.MethodTreeMatcher, BugChecker.NewClassTreeMatcher, BugChecker.ReturnTreeMatcher, ResultUsePolicyAnalyzer<ExpressionTree, VisitorState>, Suppressible, Serializable

public class CheckReturnValue
extends AbstractReturnValueIgnored
implements BugChecker.MethodTreeMatcher, BugChecker.ClassTreeMatcher

Author:

eaftan@google.com (Eddie Aftandilian)

See Also:

• Serialized Form

Nested Class Summary

Nested classes/interfaces inherited from class BugChecker

BugChecker.AnnotatedTypeTreeMatcher, BugChecker.AnnotationTreeMatcher, BugChecker.ArrayAccessTreeMatcher, BugChecker.ArrayTypeTreeMatcher, BugChecker.AssertTreeMatcher, BugChecker.AssignmentTreeMatcher, BugChecker.BinaryTreeMatcher, BugChecker.BindingPatternTreeMatcher, BugChecker.BlockTreeMatcher, BugChecker.BreakTreeMatcher, BugChecker.CaseTreeMatcher, BugChecker.CatchTreeMatcher, BugChecker.ClassTreeMatcher, BugChecker.CompilationUnitTreeMatcher, BugChecker.CompoundAssignmentTreeMatcher, BugChecker.ConditionalExpressionTreeMatcher, BugChecker.ContinueTreeMatcher, BugChecker.DoWhileLoopTreeMatcher, BugChecker.EmptyStatementTreeMatcher, BugChecker.EnhancedForLoopTreeMatcher, BugChecker.ExportsTreeMatcher, BugChecker.ExpressionStatementTreeMatcher, BugChecker.ForLoopTreeMatcher, BugChecker.IdentifierTreeMatcher, BugChecker.IfTreeMatcher, BugChecker.ImportTreeMatcher, BugChecker.InstanceOfTreeMatcher, BugChecker.IntersectionTypeTreeMatcher, BugChecker.LabeledStatementTreeMatcher, BugChecker.LambdaExpressionTreeMatcher, BugChecker.LiteralTreeMatcher, BugChecker.MemberReferenceTreeMatcher, BugChecker.MemberSelectTreeMatcher, BugChecker.MethodInvocationTreeMatcher, BugChecker.MethodTreeMatcher, BugChecker.ModifiersTreeMatcher, BugChecker.ModuleTreeMatcher, BugChecker.NewArrayTreeMatcher, BugChecker.NewClassTreeMatcher, BugChecker.OpensTreeMatcher, BugChecker.PackageTreeMatcher, BugChecker.ParameterizedTypeTreeMatcher, BugChecker.ParenthesizedTreeMatcher, BugChecker.PrimitiveTypeTreeMatcher, BugChecker.ProvidesTreeMatcher, BugChecker.RequiresTreeMatcher, BugChecker.ReturnTreeMatcher, BugChecker.SuppressibleTreePathScanner<R,P>, BugChecker.SwitchExpressionTreeMatcher, BugChecker.SwitchTreeMatcher, BugChecker.SynchronizedTreeMatcher, BugChecker.ThrowTreeMatcher, BugChecker.TryTreeMatcher, BugChecker.TypeCastTreeMatcher, BugChecker.TypeParameterTreeMatcher, BugChecker.UnaryTreeMatcher, BugChecker.UnionTypeTreeMatcher, BugChecker.UsesTreeMatcher, BugChecker.VariableTreeMatcher, BugChecker.WhileLoopTreeMatcher, BugChecker.WildcardTreeMatcher, BugChecker.YieldTreeMatcher

Field Summary

Fields

Modifier and Type	Field	Description
static final String	CHECK_ALL_CONSTRUCTORS
static final String	CHECK_ALL_METHODS

Method Summary

Modifier and Type	Method	Description
protected Description	describeReturnValueIgnored(MemberReferenceTree tree, VisitorState state)	Uses the default description for results ignored via a method reference.
protected Description	describeReturnValueIgnored(MethodInvocationTree tree, VisitorState state)	Fixes the error by assigning the result of the call to the receiver reference, or deleting the method call.
protected Description	describeReturnValueIgnored(NewClassTree tree, VisitorState state)	Uses the default description for results ignored via a constructor call.
com.google.common.collect.ImmutableMap<String,?>	getMatchMetadata(ExpressionTree tree, VisitorState state)	Returns a map of optional metadata about why this check matched the given expression.
ResultUsePolicy	getMethodPolicy(ExpressionTree expression, VisitorState state)	Returns the ResultUsePolicy for the method used in the given expression.
boolean	isCovered(ExpressionTree tree, VisitorState state)	Returns whether this checker makes any determination about whether the given expression's return value should be used or not.
Description	matchClass(ClassTree tree, VisitorState state)	Validate that at most one of CheckReturnValue and CanIgnoreReturnValue are applied to a class (or interface or enum).
Description	matchMethod(MethodTree tree, VisitorState state)	Validate @CheckReturnValue and CanIgnoreReturnValue usage on methods.
Matcher<ExpressionTree>	specializedMatcher()	Return a matcher for method invocations in which the method being called should be considered must-be-used.

Methods inherited from class AbstractReturnValueIgnored

allowInExceptionThrowers, getMessage, lostType, lostTypeMessage, matchMemberReference, matchMethodInvocation, matchNewClass, matchReturn

Methods inherited from class BugChecker

allNames, buildDescription, buildDescription, buildDescription, canonicalName, customSuppressionAnnotations, defaultSeverity, describeMatch, describeMatch, describeMatch, describeMatch, describeMatch, describeMatch, disableable, equals, hashCode, isSuppressed, isSuppressed, isSuppressed, isSuppressed, linkUrl, message, supportsSuppressWarnings, suppressedByAnyOf, suppressedRegions

Methods inherited from class Object

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

Methods inherited from interface ResultUsePolicyAnalyzer

allNames, canonicalName

Methods inherited from interface Suppressible

allNames, canonicalName, customSuppressionAnnotations, supportsSuppressWarnings, suppressedByAnyOf

Field Details

CHECK_ALL_CONSTRUCTORS

public static final String CHECK_ALL_CONSTRUCTORS

See Also:

• Constant Field Values

CHECK_ALL_METHODS

public static final String CHECK_ALL_METHODS

See Also:

• Constant Field Values

Method Details

specializedMatcher

public Matcher<ExpressionTree> specializedMatcher()

Return a matcher for method invocations in which the method being called should be considered must-be-used.

Specified by:

specializedMatcher in class AbstractReturnValueIgnored

getMethodPolicy

public ResultUsePolicy getMethodPolicy(ExpressionTree expression,
 VisitorState state)

Description copied from interface: ResultUsePolicyAnalyzer

Returns the ResultUsePolicy for the method used in the given expression.

Specified by:

getMethodPolicy in interface ResultUsePolicyAnalyzer<ExpressionTree, VisitorState>

Overrides:

getMethodPolicy in class AbstractReturnValueIgnored

isCovered

public boolean isCovered(ExpressionTree tree,
 VisitorState state)

Description copied from interface: ResultUsePolicyAnalyzer

Returns whether this checker makes any determination about whether the given expression's return value should be used or not. Most checkers either determine that an expression is CRV or make no determination.

Specified by:

isCovered in interface ResultUsePolicyAnalyzer<ExpressionTree, VisitorState>

Overrides:

isCovered in class AbstractReturnValueIgnored

getMatchMetadata

public com.google.common.collect.ImmutableMap<String,?> getMatchMetadata(ExpressionTree tree,
 VisitorState state)

Description copied from interface: ResultUsePolicyAnalyzer

Returns a map of optional metadata about why this check matched the given expression.

Specified by:

getMatchMetadata in interface ResultUsePolicyAnalyzer<ExpressionTree, VisitorState>

matchMethod

public Description matchMethod(MethodTree tree,
 VisitorState state)

Validate @CheckReturnValue and CanIgnoreReturnValue usage on methods.

The annotations should not both be applied to the same method.

The annotations should not be applied to void-returning methods. Doing so makes no sense, because there is no return value to check.

Specified by:

matchMethod in interface BugChecker.MethodTreeMatcher

matchClass

public Description matchClass(ClassTree tree,
 VisitorState state)

Validate that at most one of CheckReturnValue and CanIgnoreReturnValue are applied to a class (or interface or enum).

Specified by:

matchClass in interface BugChecker.ClassTreeMatcher

describeReturnValueIgnored

protected Description describeReturnValueIgnored(MethodInvocationTree tree,
 VisitorState state)

Description copied from class: AbstractReturnValueIgnored

Fixes the error by assigning the result of the call to the receiver reference, or deleting the method call. Subclasses may override if they prefer a different description.

Overrides:

describeReturnValueIgnored in class AbstractReturnValueIgnored

describeReturnValueIgnored

protected Description describeReturnValueIgnored(NewClassTree tree,
 VisitorState state)

Description copied from class: AbstractReturnValueIgnored

Uses the default description for results ignored via a constructor call. Subclasses may override if they prefer a different description.

Overrides:

describeReturnValueIgnored in class AbstractReturnValueIgnored

describeReturnValueIgnored

protected Description describeReturnValueIgnored(MemberReferenceTree tree,
 VisitorState state)

Description copied from class: AbstractReturnValueIgnored

Uses the default description for results ignored via a method reference. Subclasses may override if they prefer a different description.

Overrides:

describeReturnValueIgnored in class AbstractReturnValueIgnored