Class UnusedReturnValueMatcher

java.lang.Object

com.google.errorprone.matchers.UnusedReturnValueMatcher

All Implemented Interfaces:

Matcher<com.sun.source.tree.ExpressionTree>, Serializable

@CheckReturnValue
public final class UnusedReturnValueMatcher
extends Object
implements Matcher<com.sun.source.tree.ExpressionTree>

Matches expressions that invoke or reference a non-void method or constructor and which do not use their return value and are not in a context where non-use of the return value is allowed.

See Also:

• Serialized Form

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static enum	UnusedReturnValueMatcher.AllowReason	Enumeration of known reasons that an unused return value may be allowed because of the context in which the method is used.

Method Summary

Modifier and Type	Method	Description
static boolean	expectedExceptionTest(VisitorState state)	Allow return values to be ignored in tests that expect an exception to be thrown.
static UnusedReturnValueMatcher	get(boolean allowInExceptionThrowers)	Gets an instance of this matcher.
Stream<UnusedReturnValueMatcher.AllowReason>	getAllowReasons(com.sun.source.tree.ExpressionTree tree, VisitorState state)	Returns a stream of reasons the given expression is allowed to have an unused return value based on its context.
boolean	isAllowed(com.sun.source.tree.ExpressionTree tree, VisitorState state)	Returns true if the given expression is allowed to have an unused return value based on its context.
static boolean	isReturnValueUnused(com.sun.source.tree.ExpressionTree tree, VisitorState state)	Returns true if and only if the given tree is an invocation of or reference to a constructor or non-void method for which the return value is considered unused.
boolean	matches(com.sun.source.tree.ExpressionTree tree, VisitorState state)
static boolean	mockitoInvocation(com.sun.source.tree.Tree tree, VisitorState state)	Don't match the method that is invoked through Mockito.verify(t) or doReturn(val).when(t).

Methods inherited from class java.lang.Object

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

Method Details

get

public static UnusedReturnValueMatcher get(boolean allowInExceptionThrowers)

Gets an instance of this matcher.

matches

public boolean matches(com.sun.source.tree.ExpressionTree tree,
 VisitorState state)

Specified by:

matches in interface Matcher<com.sun.source.tree.ExpressionTree>

isReturnValueUnused

public static boolean isReturnValueUnused(com.sun.source.tree.ExpressionTree tree,
 VisitorState state)

Returns true if and only if the given tree is an invocation of or reference to a constructor or non-void method for which the return value is considered unused.

isAllowed

public boolean isAllowed(com.sun.source.tree.ExpressionTree tree,
 VisitorState state)

Returns true if the given expression is allowed to have an unused return value based on its context.

getAllowReasons

public Stream<UnusedReturnValueMatcher.AllowReason> getAllowReasons(com.sun.source.tree.ExpressionTree tree,
 VisitorState state)

Returns a stream of reasons the given expression is allowed to have an unused return value based on its context.

expectedExceptionTest

public static boolean expectedExceptionTest(VisitorState state)

Allow return values to be ignored in tests that expect an exception to be thrown.

mockitoInvocation

public static boolean mockitoInvocation(com.sun.source.tree.Tree tree,
 VisitorState state)

Don't match the method that is invoked through Mockito.verify(t) or doReturn(val).when(t).